Emerging Infections

A case of locally acquired dengue fever has been confirmed in a resident of Baldwin Park, California, according to a press release from the Los Angeles County Department of Public Health. This locally acquired case of dengue is the third to be reported in California and the first to be reported by the Los Angeles County Department of Public Health; cases were confirmed in Pasadena and Long Beach, California, in the fall of 2023.

“Dengue is the most common insect-borne viral infection in the world, with a wide geographic spread; we know that we have mosquitoes capable of carrying and transmitting the virus in the United States already, and Los Angeles county is a major epicenter for international travel and trade,” James Lawler, MD, associate director for International Programs and Innovation at the Global Center for Health Security and professor in the Infectious Diseases Division at the University of Nebraska Medical Center, Omaha, Nebraska, said in an interview.

Although the patient had no known history of travel to a dengue-endemic area, the potential risk for widespread transmission of the virus in the Los Angeles County area remains low, and no additional suspected cases of locally acquired dengue have been identified, according to the release. However, the recent cases highlight the need for vigilance on the part of the public to reduce transmission of mosquito-borne infections, the public health department noted.

Most cases of dengue occur in people who have traveled to areas where the disease is more common, mainly tropical and subtropical areas, according to the press release. However, the types of mosquitoes that spread dengue exist in parts of the United States, so locally acquired infections can occur.

The Centers for Disease Control and Prevention (CDC) issued an official health advisory in June 2024 about an increased risk for dengue infections in the United States. According to the advisory, 745 cases of dengue were identified in US travelers to endemic areas between January 1, 2024, and June 24, 2024.

The CDC advises clinicians to maintain a high level of suspicion for dengue among individuals with fever and recent travel to areas with frequent dengue transmission, but also to consider locally acquired disease in areas of mosquito vectors.

In clinical practice, dengue may be difficult to differentiate from other febrile systemic infections, Dr. Lawler noted. “Joint pain, low back pain, and headache (often retro-orbital) are common and can be severe, and a rash often appears several days into illness,” he noted.

Do not delay treatment in suspected cases while waiting for test results, the CDC emphasized in the advisory. Food and Drug Administration–approved tests for dengue include RT-PCR and IgM antibody tests or NS1 and IgM antibody tests.

“Severe dengue can be life-threatening and progress to a hemorrhagic fever-like syndrome, and patients with severe dengue should be cared for on a high-acuity or intensive care setting, with close monitoring of labs and fluid status,” Dr. Lawler told this news organization.

The World Health Organization has published guidelines for the management of dengue, which Dr. Lawler strongly recommends to clinicians in the rare event that they are facing a severe case. The treatment for dengue is supportive care, according to the CDC; a vaccine that was deemed safe and effective is no longer being manufactured because of low demand.

Most symptoms last for 2-7 days, and most patients recover within a week, but approximately 1 in 20 may develop severe disease, according to the Los Angeles County Department of Public Health.

Approximately one quarter of dengue infections are symptomatic, and clinicians should know the signs of progression to severe disease, which include abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy or restlessness, and liver enlargement, according to the CDC.
 

Local Dengue Not Unexpected

“Sadly, I am not surprised at another locally acquired case of dengue fever in the United States,” said Dr. Lawler. “We also have seen a trend of more historically tropical, insect-borne diseases popping up with locally acquired cases in the United States,” he noted.

Dr. Lawler suggested that “the erosion of state and local public health” is a major contributor to the increase in dengue cases. For more than 100 years, activities of state and local public health officials had significantly curtailed mosquito-borne diseases through aggressive control programs, “but we seem to be losing ground over the last several years,” he said.

“Locally acquired dengue cases are still rare in the United States,” he added. “However, people can protect themselves against dengue and more common arthropod-borne infections by taking precautions to cover up and wear insect repellent while outdoors.”

In addition, the Los Angeles County Department of Public Health emphasized in its press release that local residents reduce their risk for contact with mosquitoes by removing areas of standing water on their property and ensuring well-fitted screens on doors and windows.

Dr. Lawler had no financial conflicts to disclose.
 

A version of this article first appeared on Medscape.com.

A case of locally acquired dengue fever has been confirmed in a resident of Baldwin Park, California, according to a press release from the Los Angeles County Department of Public Health. This locally acquired case of dengue is the third to be reported in California and the first to be reported by the Los Angeles County Department of Public Health; cases were confirmed in Pasadena and Long Beach, California, in the fall of 2023.

“Dengue is the most common insect-borne viral infection in the world, with a wide geographic spread; we know that we have mosquitoes capable of carrying and transmitting the virus in the United States already, and Los Angeles county is a major epicenter for international travel and trade,” James Lawler, MD, associate director for International Programs and Innovation at the Global Center for Health Security and professor in the Infectious Diseases Division at the University of Nebraska Medical Center, Omaha, Nebraska, said in an interview.

Although the patient had no known history of travel to a dengue-endemic area, the potential risk for widespread transmission of the virus in the Los Angeles County area remains low, and no additional suspected cases of locally acquired dengue have been identified, according to the release. However, the recent cases highlight the need for vigilance on the part of the public to reduce transmission of mosquito-borne infections, the public health department noted.

Most cases of dengue occur in people who have traveled to areas where the disease is more common, mainly tropical and subtropical areas, according to the press release. However, the types of mosquitoes that spread dengue exist in parts of the United States, so locally acquired infections can occur.

The Centers for Disease Control and Prevention (CDC) issued an official health advisory in June 2024 about an increased risk for dengue infections in the United States. According to the advisory, 745 cases of dengue were identified in US travelers to endemic areas between January 1, 2024, and June 24, 2024.

The CDC advises clinicians to maintain a high level of suspicion for dengue among individuals with fever and recent travel to areas with frequent dengue transmission, but also to consider locally acquired disease in areas of mosquito vectors.

In clinical practice, dengue may be difficult to differentiate from other febrile systemic infections, Dr. Lawler noted. “Joint pain, low back pain, and headache (often retro-orbital) are common and can be severe, and a rash often appears several days into illness,” he noted.

Do not delay treatment in suspected cases while waiting for test results, the CDC emphasized in the advisory. Food and Drug Administration–approved tests for dengue include RT-PCR and IgM antibody tests or NS1 and IgM antibody tests.

“Severe dengue can be life-threatening and progress to a hemorrhagic fever-like syndrome, and patients with severe dengue should be cared for on a high-acuity or intensive care setting, with close monitoring of labs and fluid status,” Dr. Lawler told this news organization.

The World Health Organization has published guidelines for the management of dengue, which Dr. Lawler strongly recommends to clinicians in the rare event that they are facing a severe case. The treatment for dengue is supportive care, according to the CDC; a vaccine that was deemed safe and effective is no longer being manufactured because of low demand.

Most symptoms last for 2-7 days, and most patients recover within a week, but approximately 1 in 20 may develop severe disease, according to the Los Angeles County Department of Public Health.

Approximately one quarter of dengue infections are symptomatic, and clinicians should know the signs of progression to severe disease, which include abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy or restlessness, and liver enlargement, according to the CDC.
 

Local Dengue Not Unexpected

“Sadly, I am not surprised at another locally acquired case of dengue fever in the United States,” said Dr. Lawler. “We also have seen a trend of more historically tropical, insect-borne diseases popping up with locally acquired cases in the United States,” he noted.

Dr. Lawler suggested that “the erosion of state and local public health” is a major contributor to the increase in dengue cases. For more than 100 years, activities of state and local public health officials had significantly curtailed mosquito-borne diseases through aggressive control programs, “but we seem to be losing ground over the last several years,” he said.

“Locally acquired dengue cases are still rare in the United States,” he added. “However, people can protect themselves against dengue and more common arthropod-borne infections by taking precautions to cover up and wear insect repellent while outdoors.”

In addition, the Los Angeles County Department of Public Health emphasized in its press release that local residents reduce their risk for contact with mosquitoes by removing areas of standing water on their property and ensuring well-fitted screens on doors and windows.

Dr. Lawler had no financial conflicts to disclose.
 

A version of this article first appeared on Medscape.com.

A case of locally acquired dengue fever has been confirmed in a resident of Baldwin Park, California, according to a press release from the Los Angeles County Department of Public Health. This locally acquired case of dengue is the third to be reported in California and the first to be reported by the Los Angeles County Department of Public Health; cases were confirmed in Pasadena and Long Beach, California, in the fall of 2023.

“Dengue is the most common insect-borne viral infection in the world, with a wide geographic spread; we know that we have mosquitoes capable of carrying and transmitting the virus in the United States already, and Los Angeles county is a major epicenter for international travel and trade,” James Lawler, MD, associate director for International Programs and Innovation at the Global Center for Health Security and professor in the Infectious Diseases Division at the University of Nebraska Medical Center, Omaha, Nebraska, said in an interview.

Although the patient had no known history of travel to a dengue-endemic area, the potential risk for widespread transmission of the virus in the Los Angeles County area remains low, and no additional suspected cases of locally acquired dengue have been identified, according to the release. However, the recent cases highlight the need for vigilance on the part of the public to reduce transmission of mosquito-borne infections, the public health department noted.

Most cases of dengue occur in people who have traveled to areas where the disease is more common, mainly tropical and subtropical areas, according to the press release. However, the types of mosquitoes that spread dengue exist in parts of the United States, so locally acquired infections can occur.

The Centers for Disease Control and Prevention (CDC) issued an official health advisory in June 2024 about an increased risk for dengue infections in the United States. According to the advisory, 745 cases of dengue were identified in US travelers to endemic areas between January 1, 2024, and June 24, 2024.

The CDC advises clinicians to maintain a high level of suspicion for dengue among individuals with fever and recent travel to areas with frequent dengue transmission, but also to consider locally acquired disease in areas of mosquito vectors.

In clinical practice, dengue may be difficult to differentiate from other febrile systemic infections, Dr. Lawler noted. “Joint pain, low back pain, and headache (often retro-orbital) are common and can be severe, and a rash often appears several days into illness,” he noted.

Do not delay treatment in suspected cases while waiting for test results, the CDC emphasized in the advisory. Food and Drug Administration–approved tests for dengue include RT-PCR and IgM antibody tests or NS1 and IgM antibody tests.

“Severe dengue can be life-threatening and progress to a hemorrhagic fever-like syndrome, and patients with severe dengue should be cared for on a high-acuity or intensive care setting, with close monitoring of labs and fluid status,” Dr. Lawler told this news organization.

The World Health Organization has published guidelines for the management of dengue, which Dr. Lawler strongly recommends to clinicians in the rare event that they are facing a severe case. The treatment for dengue is supportive care, according to the CDC; a vaccine that was deemed safe and effective is no longer being manufactured because of low demand.

Most symptoms last for 2-7 days, and most patients recover within a week, but approximately 1 in 20 may develop severe disease, according to the Los Angeles County Department of Public Health.

Approximately one quarter of dengue infections are symptomatic, and clinicians should know the signs of progression to severe disease, which include abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy or restlessness, and liver enlargement, according to the CDC.
 

Local Dengue Not Unexpected

“Sadly, I am not surprised at another locally acquired case of dengue fever in the United States,” said Dr. Lawler. “We also have seen a trend of more historically tropical, insect-borne diseases popping up with locally acquired cases in the United States,” he noted.

Dr. Lawler suggested that “the erosion of state and local public health” is a major contributor to the increase in dengue cases. For more than 100 years, activities of state and local public health officials had significantly curtailed mosquito-borne diseases through aggressive control programs, “but we seem to be losing ground over the last several years,” he said.

“Locally acquired dengue cases are still rare in the United States,” he added. “However, people can protect themselves against dengue and more common arthropod-borne infections by taking precautions to cover up and wear insect repellent while outdoors.”

In addition, the Los Angeles County Department of Public Health emphasized in its press release that local residents reduce their risk for contact with mosquitoes by removing areas of standing water on their property and ensuring well-fitted screens on doors and windows.

Dr. Lawler had no financial conflicts to disclose.
 

A version of this article first appeared on Medscape.com.

Listeriosis during pregnancy, when invasive, can be fatal for the fetus, with a rate of fetal loss or neonatal death of 29%, investigators reported in an article alerting clinicians to this condition.

The article was prompted when the Reproductive Infectious Diseases team at The University of British Columbia in Vancouver, British Columbia, Canada, “received many phone calls from concerned doctors and patients after the plant-based milk recall in early July,” Jeffrey Man Hay Wong, MD, told this news organization. “With such concerns, we updated our British Columbia guidelines for our patients but quickly realized that our recommendations would be useful across the country.”

The article was published online in the Canadian Medical Association Journal.


 

Five Key Points

Dr. Wong and colleagues provided the following five points and recommendations:

First, invasive listeriosis (bacteremia or meningitis) in pregnancy can have major fetal consequences, including fetal loss or neonatal death in 29% of cases. Affected patients can be asymptomatic or experience gastrointestinal symptoms, myalgias, fevers, acute respiratory distress syndrome, or sepsis.

Second, pregnant people should avoid foods at a high risk for Listeria monocytogenes contamination, including unpasteurized dairy products, luncheon meats, refrigerated meat spreads, and prepared salads. They also should stay aware of Health Canada recalls.

Third, it is not necessary to investigate or treat patients who may have ingested contaminated food but are asymptomatic. Listeriosis can present at 2-3 months after exposure because the incubation period can be as long as 70 days.

Fourth, for patients with mild gastroenteritis or flu-like symptoms who may have ingested contaminated food, obtaining blood cultures or starting a 2-week course of oral amoxicillin (500 mg, three times daily) could be considered.

Fifth, for patients with fever and possible exposure to L monocytogenes, blood cultures should be drawn immediately, and high-dose ampicillin should be initiated, along with electronic fetal heart rate monitoring.

“While choosing safer foods in pregnancy is recommended, it is most important to be aware of Health Canada food recalls and pay attention to symptoms if you’ve ingested these foods,” said Dr. Wong. “Working with the BC Centre for Disease Control, our teams are actively monitoring for cases of listeriosis in pregnancy here in British Columbia.

“Thankfully,” he said, “there haven’t been any confirmed cases in British Columbia related to the plant-based milk recall, though the bacteria’s incubation period can be up to 70 days in pregnancy.”
 

No Increase Suspected

Commenting on the article, Khady Diouf, MD, director of global obstetrics and gynecology at Brigham and Women’s Hospital in Boston, said, “It summarizes the main management, which is based mostly on expert opinion.”

US clinicians also should be reminded about listeriosis in pregnancy, she noted, pointing to “helpful guidance” from the American College of Obstetrics and Gynecology.

Although the United States similarly experienced a recent listeriosis outbreak resulting from contaminated deli meats, both Dr. Wong and Dr. Diouf said that these outbreaks do not seem to signal an increase in listeriosis cases overall.

“Food-borne listeriosis seems to come in waves,” said Dr. Wong. “At a public health level, we certainly have better surveillance programs for Listeria infections. In 2023, Health Canada updated its Policy on L monocytogenes in ready-to-eat foods, which emphasizes the good manufacturing practices recommended for food processing environments to identify outbreaks earlier.”

“I think we get these recalls yearly, and this has been the case for as long as I can remember,” Dr. Diouf agreed.

No funding was declared, and the authors declared no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Listeriosis during pregnancy, when invasive, can be fatal for the fetus, with a rate of fetal loss or neonatal death of 29%, investigators reported in an article alerting clinicians to this condition.

The article was prompted when the Reproductive Infectious Diseases team at The University of British Columbia in Vancouver, British Columbia, Canada, “received many phone calls from concerned doctors and patients after the plant-based milk recall in early July,” Jeffrey Man Hay Wong, MD, told this news organization. “With such concerns, we updated our British Columbia guidelines for our patients but quickly realized that our recommendations would be useful across the country.”

The article was published online in the Canadian Medical Association Journal.


 

Five Key Points

Dr. Wong and colleagues provided the following five points and recommendations:

First, invasive listeriosis (bacteremia or meningitis) in pregnancy can have major fetal consequences, including fetal loss or neonatal death in 29% of cases. Affected patients can be asymptomatic or experience gastrointestinal symptoms, myalgias, fevers, acute respiratory distress syndrome, or sepsis.

Second, pregnant people should avoid foods at a high risk for Listeria monocytogenes contamination, including unpasteurized dairy products, luncheon meats, refrigerated meat spreads, and prepared salads. They also should stay aware of Health Canada recalls.

Third, it is not necessary to investigate or treat patients who may have ingested contaminated food but are asymptomatic. Listeriosis can present at 2-3 months after exposure because the incubation period can be as long as 70 days.

Fourth, for patients with mild gastroenteritis or flu-like symptoms who may have ingested contaminated food, obtaining blood cultures or starting a 2-week course of oral amoxicillin (500 mg, three times daily) could be considered.

Fifth, for patients with fever and possible exposure to L monocytogenes, blood cultures should be drawn immediately, and high-dose ampicillin should be initiated, along with electronic fetal heart rate monitoring.

“While choosing safer foods in pregnancy is recommended, it is most important to be aware of Health Canada food recalls and pay attention to symptoms if you’ve ingested these foods,” said Dr. Wong. “Working with the BC Centre for Disease Control, our teams are actively monitoring for cases of listeriosis in pregnancy here in British Columbia.

“Thankfully,” he said, “there haven’t been any confirmed cases in British Columbia related to the plant-based milk recall, though the bacteria’s incubation period can be up to 70 days in pregnancy.”
 

No Increase Suspected

Commenting on the article, Khady Diouf, MD, director of global obstetrics and gynecology at Brigham and Women’s Hospital in Boston, said, “It summarizes the main management, which is based mostly on expert opinion.”

US clinicians also should be reminded about listeriosis in pregnancy, she noted, pointing to “helpful guidance” from the American College of Obstetrics and Gynecology.

Although the United States similarly experienced a recent listeriosis outbreak resulting from contaminated deli meats, both Dr. Wong and Dr. Diouf said that these outbreaks do not seem to signal an increase in listeriosis cases overall.

“Food-borne listeriosis seems to come in waves,” said Dr. Wong. “At a public health level, we certainly have better surveillance programs for Listeria infections. In 2023, Health Canada updated its Policy on L monocytogenes in ready-to-eat foods, which emphasizes the good manufacturing practices recommended for food processing environments to identify outbreaks earlier.”

“I think we get these recalls yearly, and this has been the case for as long as I can remember,” Dr. Diouf agreed.

No funding was declared, and the authors declared no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Listeriosis during pregnancy, when invasive, can be fatal for the fetus, with a rate of fetal loss or neonatal death of 29%, investigators reported in an article alerting clinicians to this condition.

The article was prompted when the Reproductive Infectious Diseases team at The University of British Columbia in Vancouver, British Columbia, Canada, “received many phone calls from concerned doctors and patients after the plant-based milk recall in early July,” Jeffrey Man Hay Wong, MD, told this news organization. “With such concerns, we updated our British Columbia guidelines for our patients but quickly realized that our recommendations would be useful across the country.”

The article was published online in the Canadian Medical Association Journal.


 

Five Key Points

Dr. Wong and colleagues provided the following five points and recommendations:

First, invasive listeriosis (bacteremia or meningitis) in pregnancy can have major fetal consequences, including fetal loss or neonatal death in 29% of cases. Affected patients can be asymptomatic or experience gastrointestinal symptoms, myalgias, fevers, acute respiratory distress syndrome, or sepsis.

Second, pregnant people should avoid foods at a high risk for Listeria monocytogenes contamination, including unpasteurized dairy products, luncheon meats, refrigerated meat spreads, and prepared salads. They also should stay aware of Health Canada recalls.

Third, it is not necessary to investigate or treat patients who may have ingested contaminated food but are asymptomatic. Listeriosis can present at 2-3 months after exposure because the incubation period can be as long as 70 days.

Fourth, for patients with mild gastroenteritis or flu-like symptoms who may have ingested contaminated food, obtaining blood cultures or starting a 2-week course of oral amoxicillin (500 mg, three times daily) could be considered.

Fifth, for patients with fever and possible exposure to L monocytogenes, blood cultures should be drawn immediately, and high-dose ampicillin should be initiated, along with electronic fetal heart rate monitoring.

“While choosing safer foods in pregnancy is recommended, it is most important to be aware of Health Canada food recalls and pay attention to symptoms if you’ve ingested these foods,” said Dr. Wong. “Working with the BC Centre for Disease Control, our teams are actively monitoring for cases of listeriosis in pregnancy here in British Columbia.

“Thankfully,” he said, “there haven’t been any confirmed cases in British Columbia related to the plant-based milk recall, though the bacteria’s incubation period can be up to 70 days in pregnancy.”
 

No Increase Suspected

Commenting on the article, Khady Diouf, MD, director of global obstetrics and gynecology at Brigham and Women’s Hospital in Boston, said, “It summarizes the main management, which is based mostly on expert opinion.”

US clinicians also should be reminded about listeriosis in pregnancy, she noted, pointing to “helpful guidance” from the American College of Obstetrics and Gynecology.

Although the United States similarly experienced a recent listeriosis outbreak resulting from contaminated deli meats, both Dr. Wong and Dr. Diouf said that these outbreaks do not seem to signal an increase in listeriosis cases overall.

“Food-borne listeriosis seems to come in waves,” said Dr. Wong. “At a public health level, we certainly have better surveillance programs for Listeria infections. In 2023, Health Canada updated its Policy on L monocytogenes in ready-to-eat foods, which emphasizes the good manufacturing practices recommended for food processing environments to identify outbreaks earlier.”

“I think we get these recalls yearly, and this has been the case for as long as I can remember,” Dr. Diouf agreed.

No funding was declared, and the authors declared no relevant financial relationships.

A version of this article first appeared on Medscape.com.

The European Centre for Disease Prevention and Control (ECDC) has issued a warning to travelers in areas in South and Central America and the Caribbean affected by a current outbreak of Oropouche virus (OROV) disease. The ECDC said that there had been more than 8000 cases reported in these areas since January, with 19 imported cases reported in Europe for the first time in June and July. Of these, 12 were in Spain, five were in Italy, and two were in Germany. 

The ECDC’s Threat Assessment Brief of Aug. 9 said that one of those affected had traveled to Brazil and the other 18 to Cuba; however, outbreaks have also been reported this year in Bolivia, Colombia, and Peru. Though the overall risk for infection to European travelers to OROV-epidemic countries was assessed as moderate, it was higher in the more affected municipalities of the northern states of Brazil and/or the Amazon region, and/or if personal protection measures are not taken.

An editorial published Aug. 8 in The Lancet Infectious Diseases described OROV as a “mysterious threat,” which there is limited knowledge about despite some half a million cases recorded since it was first detected in Trinidad and Tobago in 1955. 

OROV is transmitted primarily through bites from infected midges (Culicoides paraensis). However, some mosquitoes species can also spread the virus, which causes symptoms very similar to other arbovirus diseases from the same regions, such as dengue, chikungunya, and Zika virus infection. 

Most cases are mild, but meningitis and encephalitis can occur as well as possible fetal death and deformities after infection in pregnancy. Last month, the first fatal cases were reported in two young Brazilian women who, concerningly, had no comorbidities.

This news organization asked Jan Felix Drexler, MD, of the Institute of Virology at Charité – Universitätsmedizin in Berlin, Germany, who has studied the emergence of Oropouche fever in Latin America, what clinicians should know about OROV disease.

What are the main symptoms of OROV disease for which clinicians should be alert?

The main symptoms are not different from other arboviral infections, ie, fever, maybe joint and muscle pain, maybe rash. The problem is that we do not know how often severe disease may occur because we do not know whether the severe cases that have been postulated, including death in apparently healthy people and congenital infection, are due to increased testing; an altered virus; or an altered, more intense circulation (so that many more infections simply lead to rare severe cases appearing). Be alert and ask for testing in your patients. 

What is the differential diagnosis if a recent traveler to affected regions presents with symptoms? Are there any clues to suggest whether the disease is Oropouche as opposed to Zika, etc.?

The main message is: Do not assume a particular infection based on clinical symptoms. If your patient is returning from or living in an endemic area, consider OROV disease in the differential diagnosis.

What personal protective measures should clinicians advise travelers in affected areas to take? Do these differ from normal mosquito precautions?

Repellents are extremely important as usual. However, there are differences. Mosquito nets’ hole sizes need to be smaller than those used against the vectors of malaria or dengue; in other words, they need to have a higher mesh. The problem is that nets with high mesh are complicated in very hot and humid conditions because they also limit ventilation. Travelers should discuss with local suppliers about the best trade-off.

The risk for midge bites is likely highest at dawn and dusk in still and humid conditions. So on the one hand, one could recommend avoiding those areas and being outside during those times of the day. On the other hand, specific recommendations cannot be made robustly because we cannot exclude other invertebrate vectors at current knowledge. Some studies have implicated that mosquitoes may also transmit the virus. If that holds true, then we are back to reducing any bite.

Should pregnant women be advised to avoid travel to affected regions?

Not immediately, but caution must be taken. We simply do not have sufficient data to gauge the risk for potential congenital infection. Much more epidemiologic data and controlled infection experiments will be required to make evidence-based recommendations.

All the cases reported in Europe so far were imported from Cuba and Brazil. Is there any risk for local transmission, eg, via midges/mosquitoes that might hitch a ride on an aircraft, as in cases of airport malaria?

Not immediately, but it cannot be excluded. We know very little about the infection intensity in the vectors. Controlled infection experiments, including robustness of vectors against commonly used insecticides in airplanes, need to be done.

What is the risk for an animal reservoir emerging in Europe?

We do not know, but there is also no reason for ringing the alarm bells. Controlled infection experiments and surveillance will be required.

Is treatment purely supportive or are there any specific agents worth trying in case of severe symptoms/neurologic involvement?

No specific treatment can be recommended as is. However, severe dengue illustrates the relevance of supportive treatment, which is hugely effective in reducing mortality.

The Lancet paper states: “Several laboratory tests have been developed but robust commercial tests are hardly available.” How likely is it that laboratories in Europe will have the capability to test for the Oropouche organism? 

European laboratory networks have already taken action, and testing is now available at least in the major and reference laboratories. If a clinician asks for OROV testing, they will probably get a robust answer in a reasonable timespan. Of course, that can be improved once we have more cases and more laboratories will be equipped for testing.

Is there anything else you think clinicians should be aware of?

The most important is to think beyond the textbooks we know from medical school. Things change rapidly in a connected world under altered climate conditions.

Dr. Drexler has no conflicts of interest to declare.
 

A version of this article first appeared on Medscape.com.

The European Centre for Disease Prevention and Control (ECDC) has issued a warning to travelers in areas in South and Central America and the Caribbean affected by a current outbreak of Oropouche virus (OROV) disease. The ECDC said that there had been more than 8000 cases reported in these areas since January, with 19 imported cases reported in Europe for the first time in June and July. Of these, 12 were in Spain, five were in Italy, and two were in Germany. 

The ECDC’s Threat Assessment Brief of Aug. 9 said that one of those affected had traveled to Brazil and the other 18 to Cuba; however, outbreaks have also been reported this year in Bolivia, Colombia, and Peru. Though the overall risk for infection to European travelers to OROV-epidemic countries was assessed as moderate, it was higher in the more affected municipalities of the northern states of Brazil and/or the Amazon region, and/or if personal protection measures are not taken.

An editorial published Aug. 8 in The Lancet Infectious Diseases described OROV as a “mysterious threat,” which there is limited knowledge about despite some half a million cases recorded since it was first detected in Trinidad and Tobago in 1955. 

OROV is transmitted primarily through bites from infected midges (Culicoides paraensis). However, some mosquitoes species can also spread the virus, which causes symptoms very similar to other arbovirus diseases from the same regions, such as dengue, chikungunya, and Zika virus infection. 

Most cases are mild, but meningitis and encephalitis can occur as well as possible fetal death and deformities after infection in pregnancy. Last month, the first fatal cases were reported in two young Brazilian women who, concerningly, had no comorbidities.

This news organization asked Jan Felix Drexler, MD, of the Institute of Virology at Charité – Universitätsmedizin in Berlin, Germany, who has studied the emergence of Oropouche fever in Latin America, what clinicians should know about OROV disease.

What are the main symptoms of OROV disease for which clinicians should be alert?

The main symptoms are not different from other arboviral infections, ie, fever, maybe joint and muscle pain, maybe rash. The problem is that we do not know how often severe disease may occur because we do not know whether the severe cases that have been postulated, including death in apparently healthy people and congenital infection, are due to increased testing; an altered virus; or an altered, more intense circulation (so that many more infections simply lead to rare severe cases appearing). Be alert and ask for testing in your patients. 

What is the differential diagnosis if a recent traveler to affected regions presents with symptoms? Are there any clues to suggest whether the disease is Oropouche as opposed to Zika, etc.?

The main message is: Do not assume a particular infection based on clinical symptoms. If your patient is returning from or living in an endemic area, consider OROV disease in the differential diagnosis.

What personal protective measures should clinicians advise travelers in affected areas to take? Do these differ from normal mosquito precautions?

Repellents are extremely important as usual. However, there are differences. Mosquito nets’ hole sizes need to be smaller than those used against the vectors of malaria or dengue; in other words, they need to have a higher mesh. The problem is that nets with high mesh are complicated in very hot and humid conditions because they also limit ventilation. Travelers should discuss with local suppliers about the best trade-off.

The risk for midge bites is likely highest at dawn and dusk in still and humid conditions. So on the one hand, one could recommend avoiding those areas and being outside during those times of the day. On the other hand, specific recommendations cannot be made robustly because we cannot exclude other invertebrate vectors at current knowledge. Some studies have implicated that mosquitoes may also transmit the virus. If that holds true, then we are back to reducing any bite.

Should pregnant women be advised to avoid travel to affected regions?

Not immediately, but caution must be taken. We simply do not have sufficient data to gauge the risk for potential congenital infection. Much more epidemiologic data and controlled infection experiments will be required to make evidence-based recommendations.

All the cases reported in Europe so far were imported from Cuba and Brazil. Is there any risk for local transmission, eg, via midges/mosquitoes that might hitch a ride on an aircraft, as in cases of airport malaria?

Not immediately, but it cannot be excluded. We know very little about the infection intensity in the vectors. Controlled infection experiments, including robustness of vectors against commonly used insecticides in airplanes, need to be done.

What is the risk for an animal reservoir emerging in Europe?

We do not know, but there is also no reason for ringing the alarm bells. Controlled infection experiments and surveillance will be required.

Is treatment purely supportive or are there any specific agents worth trying in case of severe symptoms/neurologic involvement?

No specific treatment can be recommended as is. However, severe dengue illustrates the relevance of supportive treatment, which is hugely effective in reducing mortality.

The Lancet paper states: “Several laboratory tests have been developed but robust commercial tests are hardly available.” How likely is it that laboratories in Europe will have the capability to test for the Oropouche organism? 

European laboratory networks have already taken action, and testing is now available at least in the major and reference laboratories. If a clinician asks for OROV testing, they will probably get a robust answer in a reasonable timespan. Of course, that can be improved once we have more cases and more laboratories will be equipped for testing.

Is there anything else you think clinicians should be aware of?

The most important is to think beyond the textbooks we know from medical school. Things change rapidly in a connected world under altered climate conditions.

Dr. Drexler has no conflicts of interest to declare.
 

A version of this article first appeared on Medscape.com.

The European Centre for Disease Prevention and Control (ECDC) has issued a warning to travelers in areas in South and Central America and the Caribbean affected by a current outbreak of Oropouche virus (OROV) disease. The ECDC said that there had been more than 8000 cases reported in these areas since January, with 19 imported cases reported in Europe for the first time in June and July. Of these, 12 were in Spain, five were in Italy, and two were in Germany. 

The ECDC’s Threat Assessment Brief of Aug. 9 said that one of those affected had traveled to Brazil and the other 18 to Cuba; however, outbreaks have also been reported this year in Bolivia, Colombia, and Peru. Though the overall risk for infection to European travelers to OROV-epidemic countries was assessed as moderate, it was higher in the more affected municipalities of the northern states of Brazil and/or the Amazon region, and/or if personal protection measures are not taken.

An editorial published Aug. 8 in The Lancet Infectious Diseases described OROV as a “mysterious threat,” which there is limited knowledge about despite some half a million cases recorded since it was first detected in Trinidad and Tobago in 1955. 

OROV is transmitted primarily through bites from infected midges (Culicoides paraensis). However, some mosquitoes species can also spread the virus, which causes symptoms very similar to other arbovirus diseases from the same regions, such as dengue, chikungunya, and Zika virus infection. 

Most cases are mild, but meningitis and encephalitis can occur as well as possible fetal death and deformities after infection in pregnancy. Last month, the first fatal cases were reported in two young Brazilian women who, concerningly, had no comorbidities.

This news organization asked Jan Felix Drexler, MD, of the Institute of Virology at Charité – Universitätsmedizin in Berlin, Germany, who has studied the emergence of Oropouche fever in Latin America, what clinicians should know about OROV disease.

What are the main symptoms of OROV disease for which clinicians should be alert?

The main symptoms are not different from other arboviral infections, ie, fever, maybe joint and muscle pain, maybe rash. The problem is that we do not know how often severe disease may occur because we do not know whether the severe cases that have been postulated, including death in apparently healthy people and congenital infection, are due to increased testing; an altered virus; or an altered, more intense circulation (so that many more infections simply lead to rare severe cases appearing). Be alert and ask for testing in your patients. 

What is the differential diagnosis if a recent traveler to affected regions presents with symptoms? Are there any clues to suggest whether the disease is Oropouche as opposed to Zika, etc.?

The main message is: Do not assume a particular infection based on clinical symptoms. If your patient is returning from or living in an endemic area, consider OROV disease in the differential diagnosis.

What personal protective measures should clinicians advise travelers in affected areas to take? Do these differ from normal mosquito precautions?

Repellents are extremely important as usual. However, there are differences. Mosquito nets’ hole sizes need to be smaller than those used against the vectors of malaria or dengue; in other words, they need to have a higher mesh. The problem is that nets with high mesh are complicated in very hot and humid conditions because they also limit ventilation. Travelers should discuss with local suppliers about the best trade-off.

The risk for midge bites is likely highest at dawn and dusk in still and humid conditions. So on the one hand, one could recommend avoiding those areas and being outside during those times of the day. On the other hand, specific recommendations cannot be made robustly because we cannot exclude other invertebrate vectors at current knowledge. Some studies have implicated that mosquitoes may also transmit the virus. If that holds true, then we are back to reducing any bite.

Should pregnant women be advised to avoid travel to affected regions?

Not immediately, but caution must be taken. We simply do not have sufficient data to gauge the risk for potential congenital infection. Much more epidemiologic data and controlled infection experiments will be required to make evidence-based recommendations.

All the cases reported in Europe so far were imported from Cuba and Brazil. Is there any risk for local transmission, eg, via midges/mosquitoes that might hitch a ride on an aircraft, as in cases of airport malaria?

Not immediately, but it cannot be excluded. We know very little about the infection intensity in the vectors. Controlled infection experiments, including robustness of vectors against commonly used insecticides in airplanes, need to be done.

What is the risk for an animal reservoir emerging in Europe?

We do not know, but there is also no reason for ringing the alarm bells. Controlled infection experiments and surveillance will be required.

Is treatment purely supportive or are there any specific agents worth trying in case of severe symptoms/neurologic involvement?

No specific treatment can be recommended as is. However, severe dengue illustrates the relevance of supportive treatment, which is hugely effective in reducing mortality.

The Lancet paper states: “Several laboratory tests have been developed but robust commercial tests are hardly available.” How likely is it that laboratories in Europe will have the capability to test for the Oropouche organism? 

European laboratory networks have already taken action, and testing is now available at least in the major and reference laboratories. If a clinician asks for OROV testing, they will probably get a robust answer in a reasonable timespan. Of course, that can be improved once we have more cases and more laboratories will be equipped for testing.

Is there anything else you think clinicians should be aware of?

The most important is to think beyond the textbooks we know from medical school. Things change rapidly in a connected world under altered climate conditions.

Dr. Drexler has no conflicts of interest to declare.
 

A version of this article first appeared on Medscape.com.

Geographic spread of the ticks that most often cause Lyme disease in the United States and a rise in incidence of bites, resulting in 476,000 new US cases a year, have increased the chances that physicians who have never encountered a patient with Lyme disease will see their first cases.

“It’s increasing in areas where it was not seen before,” Steven E. Schutzer, MD, with the Department of Medicine, Rutgers New Jersey Medical School, Newark, said in an interview. Dr. Schutzer coauthored a report on diagnosing and treating Lyme disease with Patricia K. Coyle, MD, Department of Neurology, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York.

The report, a Curbside Consult published in New England Journal of Medicine Evidence, comes amid high season for Lyme disease. Bites from an ixodid (hard shield) tick — almost always the source of the disease in the United States — are most common from April through October.

Identifying the Bite

About 70%-90% of the time, Lyme disease will be signaled by erythema migrans (EM) or lesion expanding from the tick bite site, the authors wrote. The “classic” presentation looks like a bullseye, but most of the time the skin will show a variation of that, the authors noted.

“The presence of EM is considered the best clinical diagnostic marker for Lyme disease,” they wrote.

Other dermatologic conditions, however, can complicate diagnosis: “EM mimickers include contact dermatitis, other arthropod bites, fixed drug eruptions, granuloma annulare, cellulitis, dermatophytosis, and systemic lupus erythematosus,” they wrote.
 

Testing Steps

“The current recommendation is to do two-step testing almost simultaneously,” Dr. Schutzer said in an interview. The first, he said, is an ELISA (enzyme-linked immunosorbent assay)-type test and the second one, used for years, has been a pictoral view of a Western immunoblot showing which antigens of the Lyme bacteria, Borrelia burgdorferi, the antibodies are reacting to.

However, the pictoral view is subjective and some of the antigens could be cross-reactive. So the U.S. Food and Drug Administration (FDA) “has been allowing newer substitutes like a second ELISA-like assay that often uses more recombinant, less cross-reactive antigen targets,” he said. The authors advised that, “The second-tier test should not be performed alone without the first tier.”

Dr. Schutzer advised physicians to check with the lab they plan to use before sending samples.

“If you’re a practicing physician and you know you’re using a particular laboratory, you should familiarize yourself with them, talking to one of the clinical pathologists involved in advance to know what the limitations are.” Take the time to talk with the person overseeing the test and get tips on how they want the sample transported and how the cases should be reported, he said.

If the patient has neurological symptoms, he said, before treating talk with a neurologist who can advise whether, for instance, a spinal tap is in order or whether an emergency department visit is appropriate.

“If you just start proceeding you may mess up the diagnostic signs that could show up in a lab test. Don’t be hesitant to ask for extra input from colleagues,” Dr. Schutzer said.
 

Suspicion in Endemic Areas

On Long Island, New York, where Lyme disease is endemic, internist Ian Storch, DO, said he sees “a few cases a season.

“We have a lot of people over the summer going to the Hamptons and areas out east for the weekend and tick bites are not uncommon,” he said. “People panic.”

He said one thing it’s important to tell patients is that the tick has to be on the skin for 48-72 hours to transmit the disease. If individuals were in a wooded area and were fine before they got there and the tick was attached for less than 2 days, “they’re usually fine.”

Another issue, Dr. Storch said, is patients sometimes want to get tested for Lyme disease immediately after a tick bite. But the antibody test doesn’t turn positive for weeks, he noted, and you can get a false-negative result. “If you’re worried and you really want to test, you need to wait 6 weeks to do the blood test.”

In his region, he said that although a tick bite is a red flag, he may also suspect Lyme disease when a patient presents with otherwise unexplained joint pain, weakness, lethargy, or fever. “In our area, those are things that would make you test for Lyme.”

He also urged consideration of Lyme in this new age of long COVID. Weakness, fatigue, and lethargy are also classic symptoms of long COVID, he noted. “Keep Lyme disease in your differential because there is a lot of overlap with chronic Lyme disease,” Dr. Storch said.

Discerning Lyme from Southern Tick–Associated Rash Illness

Bonnie M. Word, MD, director of the Houston Travel Medicine Clinic in Texas, where Lyme disease is not endemic, said Lyme disease “will not and should not be on the initial differential diagnosis for those residing in nonendemic areas unless a history of travel to an endemic area is obtained.”

She noted the typical EM rash may not be as distinct or easy to discern on black and brown skin. In addition, she said, EM may have many variations in presentation, such as a crusted center or faint borders, which could lead to a delay in diagnosis and treatment. She suggested consulting the CDC guidance on Lyme disease rashes.

Another challenge in diagnosis, she said, is the patient who presents with what appears to be a classic EM lesion but does not live in a Lyme-endemic area. In Texas, Southern Tick–Associated Rash Illness (STARI) may present with a similar lesion, she said.

“It is transmitted by the Lone Star Tick, which is found in the southeast and south-central US,” Dr. Word said. “However, its habitat is moving northward and westerly,” she said.

Adding Lyme disease to the differential diagnosis is reasonable, she said, if a patient presents with neurologic symptoms “such as a facial palsy, meningitis, radiculitis, and carditis if in addition to their symptoms there is evidence of an epidemiologic link to a Lyme-endemic region.”

She noted that a detailed travel history is important as “Lyme is also endemic in Eastern Canada, Europe, states of the former Soviet Union, China, Mongolia, and Japan.”

Primary care physicians play a critical role in evaluating, diagnosing, and treating most cases of early Lyme disease, thus limiting the number of people who will develop disseminated or late Lyme disease, she said. “The two latter manifestations are most often treated by infectious disease, neurology, or rheumatology specialists.”

Treatment* 

Treatment is tailored to the clinical situation, Dr. Schutzer and Dr. Coyle write. A watch-and-wait approach may be appropriate in an asymptomatic but concerned person, even in an endemic area if the person has no known tick bite and no EM lesion.

If there is high risk of an infected ixodid tick bite in a high-incidence area and the tick was attached for at least 36 hours but less than 72 hours, one dose of doxycycline has been recommended as prophylaxis.

When a diagnosis of early nondisseminated Lyme disease is made after observation  of an EM lesion, oral antibiotics are typically used to treat for 10 to 14 days. Suggested oral antibiotics and doses are 100 mg of doxycycline twice a day, 500 mg of amoxicillin three times a day, or 500 mg of cefuroxime twice a day, the authors write.

Dr. Schutzer said he hopes the paper serves as a refresher for those physicians who regularly see Lyme disease cases and also helps those newly included in the disease’s spreading regions.

“The earlier you diagnose it, the earlier you can treat it and the better the chance for a favorable outcome,” he said.

Dr. Schutzer, Dr. Coyle, Dr. Storch, and Dr. Word reported no relevant financial relationships.

*This story was updated on August, 2, 2024.

Geographic spread of the ticks that most often cause Lyme disease in the United States and a rise in incidence of bites, resulting in 476,000 new US cases a year, have increased the chances that physicians who have never encountered a patient with Lyme disease will see their first cases.

“It’s increasing in areas where it was not seen before,” Steven E. Schutzer, MD, with the Department of Medicine, Rutgers New Jersey Medical School, Newark, said in an interview. Dr. Schutzer coauthored a report on diagnosing and treating Lyme disease with Patricia K. Coyle, MD, Department of Neurology, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York.

The report, a Curbside Consult published in New England Journal of Medicine Evidence, comes amid high season for Lyme disease. Bites from an ixodid (hard shield) tick — almost always the source of the disease in the United States — are most common from April through October.

Identifying the Bite

About 70%-90% of the time, Lyme disease will be signaled by erythema migrans (EM) or lesion expanding from the tick bite site, the authors wrote. The “classic” presentation looks like a bullseye, but most of the time the skin will show a variation of that, the authors noted.

“The presence of EM is considered the best clinical diagnostic marker for Lyme disease,” they wrote.

Other dermatologic conditions, however, can complicate diagnosis: “EM mimickers include contact dermatitis, other arthropod bites, fixed drug eruptions, granuloma annulare, cellulitis, dermatophytosis, and systemic lupus erythematosus,” they wrote.
 

Testing Steps

“The current recommendation is to do two-step testing almost simultaneously,” Dr. Schutzer said in an interview. The first, he said, is an ELISA (enzyme-linked immunosorbent assay)-type test and the second one, used for years, has been a pictoral view of a Western immunoblot showing which antigens of the Lyme bacteria, Borrelia burgdorferi, the antibodies are reacting to.

However, the pictoral view is subjective and some of the antigens could be cross-reactive. So the U.S. Food and Drug Administration (FDA) “has been allowing newer substitutes like a second ELISA-like assay that often uses more recombinant, less cross-reactive antigen targets,” he said. The authors advised that, “The second-tier test should not be performed alone without the first tier.”

Dr. Schutzer advised physicians to check with the lab they plan to use before sending samples.

“If you’re a practicing physician and you know you’re using a particular laboratory, you should familiarize yourself with them, talking to one of the clinical pathologists involved in advance to know what the limitations are.” Take the time to talk with the person overseeing the test and get tips on how they want the sample transported and how the cases should be reported, he said.

If the patient has neurological symptoms, he said, before treating talk with a neurologist who can advise whether, for instance, a spinal tap is in order or whether an emergency department visit is appropriate.

“If you just start proceeding you may mess up the diagnostic signs that could show up in a lab test. Don’t be hesitant to ask for extra input from colleagues,” Dr. Schutzer said.
 

Suspicion in Endemic Areas

On Long Island, New York, where Lyme disease is endemic, internist Ian Storch, DO, said he sees “a few cases a season.

“We have a lot of people over the summer going to the Hamptons and areas out east for the weekend and tick bites are not uncommon,” he said. “People panic.”

He said one thing it’s important to tell patients is that the tick has to be on the skin for 48-72 hours to transmit the disease. If individuals were in a wooded area and were fine before they got there and the tick was attached for less than 2 days, “they’re usually fine.”

Another issue, Dr. Storch said, is patients sometimes want to get tested for Lyme disease immediately after a tick bite. But the antibody test doesn’t turn positive for weeks, he noted, and you can get a false-negative result. “If you’re worried and you really want to test, you need to wait 6 weeks to do the blood test.”

In his region, he said that although a tick bite is a red flag, he may also suspect Lyme disease when a patient presents with otherwise unexplained joint pain, weakness, lethargy, or fever. “In our area, those are things that would make you test for Lyme.”

He also urged consideration of Lyme in this new age of long COVID. Weakness, fatigue, and lethargy are also classic symptoms of long COVID, he noted. “Keep Lyme disease in your differential because there is a lot of overlap with chronic Lyme disease,” Dr. Storch said.

Discerning Lyme from Southern Tick–Associated Rash Illness

Bonnie M. Word, MD, director of the Houston Travel Medicine Clinic in Texas, where Lyme disease is not endemic, said Lyme disease “will not and should not be on the initial differential diagnosis for those residing in nonendemic areas unless a history of travel to an endemic area is obtained.”

She noted the typical EM rash may not be as distinct or easy to discern on black and brown skin. In addition, she said, EM may have many variations in presentation, such as a crusted center or faint borders, which could lead to a delay in diagnosis and treatment. She suggested consulting the CDC guidance on Lyme disease rashes.

Another challenge in diagnosis, she said, is the patient who presents with what appears to be a classic EM lesion but does not live in a Lyme-endemic area. In Texas, Southern Tick–Associated Rash Illness (STARI) may present with a similar lesion, she said.

“It is transmitted by the Lone Star Tick, which is found in the southeast and south-central US,” Dr. Word said. “However, its habitat is moving northward and westerly,” she said.

Adding Lyme disease to the differential diagnosis is reasonable, she said, if a patient presents with neurologic symptoms “such as a facial palsy, meningitis, radiculitis, and carditis if in addition to their symptoms there is evidence of an epidemiologic link to a Lyme-endemic region.”

She noted that a detailed travel history is important as “Lyme is also endemic in Eastern Canada, Europe, states of the former Soviet Union, China, Mongolia, and Japan.”

Primary care physicians play a critical role in evaluating, diagnosing, and treating most cases of early Lyme disease, thus limiting the number of people who will develop disseminated or late Lyme disease, she said. “The two latter manifestations are most often treated by infectious disease, neurology, or rheumatology specialists.”

Treatment* 

Treatment is tailored to the clinical situation, Dr. Schutzer and Dr. Coyle write. A watch-and-wait approach may be appropriate in an asymptomatic but concerned person, even in an endemic area if the person has no known tick bite and no EM lesion.

If there is high risk of an infected ixodid tick bite in a high-incidence area and the tick was attached for at least 36 hours but less than 72 hours, one dose of doxycycline has been recommended as prophylaxis.

When a diagnosis of early nondisseminated Lyme disease is made after observation  of an EM lesion, oral antibiotics are typically used to treat for 10 to 14 days. Suggested oral antibiotics and doses are 100 mg of doxycycline twice a day, 500 mg of amoxicillin three times a day, or 500 mg of cefuroxime twice a day, the authors write.

Dr. Schutzer said he hopes the paper serves as a refresher for those physicians who regularly see Lyme disease cases and also helps those newly included in the disease’s spreading regions.

“The earlier you diagnose it, the earlier you can treat it and the better the chance for a favorable outcome,” he said.

Dr. Schutzer, Dr. Coyle, Dr. Storch, and Dr. Word reported no relevant financial relationships.

*This story was updated on August, 2, 2024.

Geographic spread of the ticks that most often cause Lyme disease in the United States and a rise in incidence of bites, resulting in 476,000 new US cases a year, have increased the chances that physicians who have never encountered a patient with Lyme disease will see their first cases.

“It’s increasing in areas where it was not seen before,” Steven E. Schutzer, MD, with the Department of Medicine, Rutgers New Jersey Medical School, Newark, said in an interview. Dr. Schutzer coauthored a report on diagnosing and treating Lyme disease with Patricia K. Coyle, MD, Department of Neurology, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York.

The report, a Curbside Consult published in New England Journal of Medicine Evidence, comes amid high season for Lyme disease. Bites from an ixodid (hard shield) tick — almost always the source of the disease in the United States — are most common from April through October.

Identifying the Bite

About 70%-90% of the time, Lyme disease will be signaled by erythema migrans (EM) or lesion expanding from the tick bite site, the authors wrote. The “classic” presentation looks like a bullseye, but most of the time the skin will show a variation of that, the authors noted.

“The presence of EM is considered the best clinical diagnostic marker for Lyme disease,” they wrote.

Other dermatologic conditions, however, can complicate diagnosis: “EM mimickers include contact dermatitis, other arthropod bites, fixed drug eruptions, granuloma annulare, cellulitis, dermatophytosis, and systemic lupus erythematosus,” they wrote.
 

Testing Steps

“The current recommendation is to do two-step testing almost simultaneously,” Dr. Schutzer said in an interview. The first, he said, is an ELISA (enzyme-linked immunosorbent assay)-type test and the second one, used for years, has been a pictoral view of a Western immunoblot showing which antigens of the Lyme bacteria, Borrelia burgdorferi, the antibodies are reacting to.

However, the pictoral view is subjective and some of the antigens could be cross-reactive. So the U.S. Food and Drug Administration (FDA) “has been allowing newer substitutes like a second ELISA-like assay that often uses more recombinant, less cross-reactive antigen targets,” he said. The authors advised that, “The second-tier test should not be performed alone without the first tier.”

Dr. Schutzer advised physicians to check with the lab they plan to use before sending samples.

“If you’re a practicing physician and you know you’re using a particular laboratory, you should familiarize yourself with them, talking to one of the clinical pathologists involved in advance to know what the limitations are.” Take the time to talk with the person overseeing the test and get tips on how they want the sample transported and how the cases should be reported, he said.

If the patient has neurological symptoms, he said, before treating talk with a neurologist who can advise whether, for instance, a spinal tap is in order or whether an emergency department visit is appropriate.

“If you just start proceeding you may mess up the diagnostic signs that could show up in a lab test. Don’t be hesitant to ask for extra input from colleagues,” Dr. Schutzer said.
 

Suspicion in Endemic Areas

On Long Island, New York, where Lyme disease is endemic, internist Ian Storch, DO, said he sees “a few cases a season.

“We have a lot of people over the summer going to the Hamptons and areas out east for the weekend and tick bites are not uncommon,” he said. “People panic.”

He said one thing it’s important to tell patients is that the tick has to be on the skin for 48-72 hours to transmit the disease. If individuals were in a wooded area and were fine before they got there and the tick was attached for less than 2 days, “they’re usually fine.”

Another issue, Dr. Storch said, is patients sometimes want to get tested for Lyme disease immediately after a tick bite. But the antibody test doesn’t turn positive for weeks, he noted, and you can get a false-negative result. “If you’re worried and you really want to test, you need to wait 6 weeks to do the blood test.”

In his region, he said that although a tick bite is a red flag, he may also suspect Lyme disease when a patient presents with otherwise unexplained joint pain, weakness, lethargy, or fever. “In our area, those are things that would make you test for Lyme.”

He also urged consideration of Lyme in this new age of long COVID. Weakness, fatigue, and lethargy are also classic symptoms of long COVID, he noted. “Keep Lyme disease in your differential because there is a lot of overlap with chronic Lyme disease,” Dr. Storch said.

Discerning Lyme from Southern Tick–Associated Rash Illness

Bonnie M. Word, MD, director of the Houston Travel Medicine Clinic in Texas, where Lyme disease is not endemic, said Lyme disease “will not and should not be on the initial differential diagnosis for those residing in nonendemic areas unless a history of travel to an endemic area is obtained.”

She noted the typical EM rash may not be as distinct or easy to discern on black and brown skin. In addition, she said, EM may have many variations in presentation, such as a crusted center or faint borders, which could lead to a delay in diagnosis and treatment. She suggested consulting the CDC guidance on Lyme disease rashes.

Another challenge in diagnosis, she said, is the patient who presents with what appears to be a classic EM lesion but does not live in a Lyme-endemic area. In Texas, Southern Tick–Associated Rash Illness (STARI) may present with a similar lesion, she said.

“It is transmitted by the Lone Star Tick, which is found in the southeast and south-central US,” Dr. Word said. “However, its habitat is moving northward and westerly,” she said.

Adding Lyme disease to the differential diagnosis is reasonable, she said, if a patient presents with neurologic symptoms “such as a facial palsy, meningitis, radiculitis, and carditis if in addition to their symptoms there is evidence of an epidemiologic link to a Lyme-endemic region.”

She noted that a detailed travel history is important as “Lyme is also endemic in Eastern Canada, Europe, states of the former Soviet Union, China, Mongolia, and Japan.”

Primary care physicians play a critical role in evaluating, diagnosing, and treating most cases of early Lyme disease, thus limiting the number of people who will develop disseminated or late Lyme disease, she said. “The two latter manifestations are most often treated by infectious disease, neurology, or rheumatology specialists.”

Treatment* 

Treatment is tailored to the clinical situation, Dr. Schutzer and Dr. Coyle write. A watch-and-wait approach may be appropriate in an asymptomatic but concerned person, even in an endemic area if the person has no known tick bite and no EM lesion.

If there is high risk of an infected ixodid tick bite in a high-incidence area and the tick was attached for at least 36 hours but less than 72 hours, one dose of doxycycline has been recommended as prophylaxis.

When a diagnosis of early nondisseminated Lyme disease is made after observation  of an EM lesion, oral antibiotics are typically used to treat for 10 to 14 days. Suggested oral antibiotics and doses are 100 mg of doxycycline twice a day, 500 mg of amoxicillin three times a day, or 500 mg of cefuroxime twice a day, the authors write.

Dr. Schutzer said he hopes the paper serves as a refresher for those physicians who regularly see Lyme disease cases and also helps those newly included in the disease’s spreading regions.

“The earlier you diagnose it, the earlier you can treat it and the better the chance for a favorable outcome,” he said.

Dr. Schutzer, Dr. Coyle, Dr. Storch, and Dr. Word reported no relevant financial relationships.

*This story was updated on August, 2, 2024.

Hospitals and laboratories across the United States are grappling with a shortage of Becton Dickinson BACTEC blood culture bottles that threatens to extend at least until September.

In a health advisory, the Centers for Disease Control and Prevention (CDC) warned that the critical shortage could lead to “delays in diagnosis, misdiagnosis, or other challenges” in the management of patients with infectious diseases.

Most blood cultures in the United States are performed using continuous-monitoring blood culture systems; the Becton Dickinson system is used in about half of all US laboratories and is only compatible with the brand’s BACTEC blood culture media bottles.

Healthcare providers, laboratories, healthcare facility administrators, and state, tribal, local, and territorial health departments affected by the shortage “should immediately begin to assess their situations and develop plans and options to mitigate the potential impact,” according to the health advisory.
 

What to Do

To reduce the impact of the shortage, facilities are urged to:

• Determine the type of blood culture bottles they have
• Optimize the use of blood cultures at their facility
• Take steps to prevent blood culture contamination
• Ensure that the appropriate volume of blood is collected for culture
• Assess alternate options for blood cultures
• Work with a nearby facility or send samples to another laboratory

Health departments are advised to contact hospitals and laboratories in their jurisdictions to determine whether the shortage will affect them. Health departments are also encouraged to educate others on the supply shortage, optimal use of blood cultures, and mechanisms for reporting supply chain shortages or interruptions to the Food and Drug Administration (FDA), as well as to help with communication between laboratories and facilities willing to assist others in need.

To further assist affected providers, the CDC, in collaboration with the Infectious Diseases Society of America, hosted a webinar with speakers from Johns Hopkins University, Massachusetts General Hospital, and Vanderbilt University, who shared what their institutions are doing to cope with the shortage and protect patients.
 

Why It Happened

In June, Becton Dickinson warned its customers that they may experience “intermittent delays” in the supply of some BACTEC blood culture media over the coming months because of reduced availability of plastic bottles from its supplier.

In a July 22 update, the company said the supplier issues were “more complex” than originally communicated and it is taking steps to “resolve this challenge as quickly as possible.”

In July, the FDA published a letter to healthcare providers acknowledging the supply disruptions and recommended strategies to preserve the supply for patients at highest risk.

Becton Dickinson has promised an update by September to this “dynamic and evolving situation.”

A version of this article appeared on Medscape.com.

Hospitals and laboratories across the United States are grappling with a shortage of Becton Dickinson BACTEC blood culture bottles that threatens to extend at least until September.

In a health advisory, the Centers for Disease Control and Prevention (CDC) warned that the critical shortage could lead to “delays in diagnosis, misdiagnosis, or other challenges” in the management of patients with infectious diseases.

Most blood cultures in the United States are performed using continuous-monitoring blood culture systems; the Becton Dickinson system is used in about half of all US laboratories and is only compatible with the brand’s BACTEC blood culture media bottles.

Healthcare providers, laboratories, healthcare facility administrators, and state, tribal, local, and territorial health departments affected by the shortage “should immediately begin to assess their situations and develop plans and options to mitigate the potential impact,” according to the health advisory.
 

What to Do

To reduce the impact of the shortage, facilities are urged to:

• Determine the type of blood culture bottles they have
• Optimize the use of blood cultures at their facility
• Take steps to prevent blood culture contamination
• Ensure that the appropriate volume of blood is collected for culture
• Assess alternate options for blood cultures
• Work with a nearby facility or send samples to another laboratory

Health departments are advised to contact hospitals and laboratories in their jurisdictions to determine whether the shortage will affect them. Health departments are also encouraged to educate others on the supply shortage, optimal use of blood cultures, and mechanisms for reporting supply chain shortages or interruptions to the Food and Drug Administration (FDA), as well as to help with communication between laboratories and facilities willing to assist others in need.

To further assist affected providers, the CDC, in collaboration with the Infectious Diseases Society of America, hosted a webinar with speakers from Johns Hopkins University, Massachusetts General Hospital, and Vanderbilt University, who shared what their institutions are doing to cope with the shortage and protect patients.
 

Why It Happened

In June, Becton Dickinson warned its customers that they may experience “intermittent delays” in the supply of some BACTEC blood culture media over the coming months because of reduced availability of plastic bottles from its supplier.

In a July 22 update, the company said the supplier issues were “more complex” than originally communicated and it is taking steps to “resolve this challenge as quickly as possible.”

In July, the FDA published a letter to healthcare providers acknowledging the supply disruptions and recommended strategies to preserve the supply for patients at highest risk.

Becton Dickinson has promised an update by September to this “dynamic and evolving situation.”

A version of this article appeared on Medscape.com.

Hospitals and laboratories across the United States are grappling with a shortage of Becton Dickinson BACTEC blood culture bottles that threatens to extend at least until September.

In a health advisory, the Centers for Disease Control and Prevention (CDC) warned that the critical shortage could lead to “delays in diagnosis, misdiagnosis, or other challenges” in the management of patients with infectious diseases.

Most blood cultures in the United States are performed using continuous-monitoring blood culture systems; the Becton Dickinson system is used in about half of all US laboratories and is only compatible with the brand’s BACTEC blood culture media bottles.

Healthcare providers, laboratories, healthcare facility administrators, and state, tribal, local, and territorial health departments affected by the shortage “should immediately begin to assess their situations and develop plans and options to mitigate the potential impact,” according to the health advisory.
 

What to Do

To reduce the impact of the shortage, facilities are urged to:

• Determine the type of blood culture bottles they have
• Optimize the use of blood cultures at their facility
• Take steps to prevent blood culture contamination
• Ensure that the appropriate volume of blood is collected for culture
• Assess alternate options for blood cultures
• Work with a nearby facility or send samples to another laboratory

Health departments are advised to contact hospitals and laboratories in their jurisdictions to determine whether the shortage will affect them. Health departments are also encouraged to educate others on the supply shortage, optimal use of blood cultures, and mechanisms for reporting supply chain shortages or interruptions to the Food and Drug Administration (FDA), as well as to help with communication between laboratories and facilities willing to assist others in need.

To further assist affected providers, the CDC, in collaboration with the Infectious Diseases Society of America, hosted a webinar with speakers from Johns Hopkins University, Massachusetts General Hospital, and Vanderbilt University, who shared what their institutions are doing to cope with the shortage and protect patients.
 

Why It Happened

In June, Becton Dickinson warned its customers that they may experience “intermittent delays” in the supply of some BACTEC blood culture media over the coming months because of reduced availability of plastic bottles from its supplier.

In a July 22 update, the company said the supplier issues were “more complex” than originally communicated and it is taking steps to “resolve this challenge as quickly as possible.”

In July, the FDA published a letter to healthcare providers acknowledging the supply disruptions and recommended strategies to preserve the supply for patients at highest risk.

Becton Dickinson has promised an update by September to this “dynamic and evolving situation.”

A version of this article appeared on Medscape.com.

Federal health officials with the US Centers for Disease Control and Prevention (CDC) have issued an alert, warning health professionals and the public about an increased risk for dengue virus infections in the United States.

The global incidence of dengue in 2024 is the highest on record, reported the agency.

In the Americas, more than 9.7 million cases of dengue have been reported in the first 6 months of 2024 — more than double the 4.6 million cases reported in all of 2023.

In the United States, Puerto Rico has declared a public health emergency, with 1498 dengue cases reported so far and a “higher-than-expected” number of dengue cases having been identified among US travelers in the first half of this year at 745 cases, according to the alert.

The CDC reports 197 dengue cases in Florida, 134 in New York, 50 in Massachusetts, 40 in California, 14 in Colorado, nine in Arizona, and eight in the District of Columbia, among others.

Transmitted by infected Aedes genus mosquitoes, dengue is the most common arboviral disease globally and is a nationally notifiable disease in the United States.

The six US territories and freely associated states with frequent or continuous dengue transmission are Puerto Rico, American Samoa, the US Virgin Islands, the Federated States of Micronesia, the Republic of the Marshall Islands, and the Republic of Palau.
 

Monitoring for Dengue

With rising global and domestic cases of dengue, the CDC urges healthcare providers to monitor for dengue:

• Maintain a high index of suspicion in patients with fever who have been in areas with frequent or continuous dengue transmission within 14 days before illness onset.
• Order diagnostic tests for acute dengue infection such as reverse transcription polymerase chain reaction and immunoglobulin M (IgM) antibody tests or nonstructural protein 1 antigen tests and IgM antibody tests.
• Ensure timely reporting of dengue cases to public health authorities.
• Promote mosquito bite prevention measures among people living in or visiting areas with frequent or continuous dengue transmission.

Roughly one in four dengue virus infections are symptomatic and can be mild or severe. Symptoms begin after an incubation period of about 5-7 days.

Symptoms include fever accompanied by nonspecific signs and symptoms such as nausea, vomiting, rash, muscle aches, joint pain, bone pain, pain behind the eyes, headache, or low white blood cell counts.
 

Disease Progression

Warning signs that may predict progression to severe disease include abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy or restlessness, and progressive increase in hematocrit or liver enlargement.

One in 20 people with symptomatic dengue will develop severe disease, with bleeding, shock, or respiratory distress caused by plasma leakage or end-organ impairment.

Infants aged a year or younger, pregnant people, adults aged 65 years or older, people with certain medical conditions, and those with previous dengue infections are at increased risk for severe dengue.

“Healthcare providers should be prepared to recognize, diagnose, manage, and report dengue cases to health authorities; public health partners should investigate cases and disseminate clear prevention messages to the public,” the alert stated.

The CDC is actively implementing several strategies to address the increase in cases of dengue in the United States. In early April, the agency launched a program-led emergency response and is providing monthly situational updates on dengue to partners, stakeholders, and jurisdictions.

The CDC is also expanding laboratory capacity to improve laboratory testing approaches; collaborating with state, tribal, local, and territorial health departments to strengthen dengue surveillance and recommend prevention strategies; and working to educate the public on dengue prevention.

A version of this article first appeared on Medscape.com.

Federal health officials with the US Centers for Disease Control and Prevention (CDC) have issued an alert, warning health professionals and the public about an increased risk for dengue virus infections in the United States.

The global incidence of dengue in 2024 is the highest on record, reported the agency.

In the Americas, more than 9.7 million cases of dengue have been reported in the first 6 months of 2024 — more than double the 4.6 million cases reported in all of 2023.

In the United States, Puerto Rico has declared a public health emergency, with 1498 dengue cases reported so far and a “higher-than-expected” number of dengue cases having been identified among US travelers in the first half of this year at 745 cases, according to the alert.

The CDC reports 197 dengue cases in Florida, 134 in New York, 50 in Massachusetts, 40 in California, 14 in Colorado, nine in Arizona, and eight in the District of Columbia, among others.

Transmitted by infected Aedes genus mosquitoes, dengue is the most common arboviral disease globally and is a nationally notifiable disease in the United States.

The six US territories and freely associated states with frequent or continuous dengue transmission are Puerto Rico, American Samoa, the US Virgin Islands, the Federated States of Micronesia, the Republic of the Marshall Islands, and the Republic of Palau.
 

Monitoring for Dengue

With rising global and domestic cases of dengue, the CDC urges healthcare providers to monitor for dengue:

• Maintain a high index of suspicion in patients with fever who have been in areas with frequent or continuous dengue transmission within 14 days before illness onset.
• Order diagnostic tests for acute dengue infection such as reverse transcription polymerase chain reaction and immunoglobulin M (IgM) antibody tests or nonstructural protein 1 antigen tests and IgM antibody tests.
• Ensure timely reporting of dengue cases to public health authorities.
• Promote mosquito bite prevention measures among people living in or visiting areas with frequent or continuous dengue transmission.

Roughly one in four dengue virus infections are symptomatic and can be mild or severe. Symptoms begin after an incubation period of about 5-7 days.

Symptoms include fever accompanied by nonspecific signs and symptoms such as nausea, vomiting, rash, muscle aches, joint pain, bone pain, pain behind the eyes, headache, or low white blood cell counts.
 

Disease Progression

Warning signs that may predict progression to severe disease include abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy or restlessness, and progressive increase in hematocrit or liver enlargement.

One in 20 people with symptomatic dengue will develop severe disease, with bleeding, shock, or respiratory distress caused by plasma leakage or end-organ impairment.

Infants aged a year or younger, pregnant people, adults aged 65 years or older, people with certain medical conditions, and those with previous dengue infections are at increased risk for severe dengue.

“Healthcare providers should be prepared to recognize, diagnose, manage, and report dengue cases to health authorities; public health partners should investigate cases and disseminate clear prevention messages to the public,” the alert stated.

The CDC is actively implementing several strategies to address the increase in cases of dengue in the United States. In early April, the agency launched a program-led emergency response and is providing monthly situational updates on dengue to partners, stakeholders, and jurisdictions.

The CDC is also expanding laboratory capacity to improve laboratory testing approaches; collaborating with state, tribal, local, and territorial health departments to strengthen dengue surveillance and recommend prevention strategies; and working to educate the public on dengue prevention.

A version of this article first appeared on Medscape.com.

Federal health officials with the US Centers for Disease Control and Prevention (CDC) have issued an alert, warning health professionals and the public about an increased risk for dengue virus infections in the United States.

The global incidence of dengue in 2024 is the highest on record, reported the agency.

In the Americas, more than 9.7 million cases of dengue have been reported in the first 6 months of 2024 — more than double the 4.6 million cases reported in all of 2023.

In the United States, Puerto Rico has declared a public health emergency, with 1498 dengue cases reported so far and a “higher-than-expected” number of dengue cases having been identified among US travelers in the first half of this year at 745 cases, according to the alert.

The CDC reports 197 dengue cases in Florida, 134 in New York, 50 in Massachusetts, 40 in California, 14 in Colorado, nine in Arizona, and eight in the District of Columbia, among others.

Transmitted by infected Aedes genus mosquitoes, dengue is the most common arboviral disease globally and is a nationally notifiable disease in the United States.

The six US territories and freely associated states with frequent or continuous dengue transmission are Puerto Rico, American Samoa, the US Virgin Islands, the Federated States of Micronesia, the Republic of the Marshall Islands, and the Republic of Palau.
 

Monitoring for Dengue

With rising global and domestic cases of dengue, the CDC urges healthcare providers to monitor for dengue:

• Maintain a high index of suspicion in patients with fever who have been in areas with frequent or continuous dengue transmission within 14 days before illness onset.
• Order diagnostic tests for acute dengue infection such as reverse transcription polymerase chain reaction and immunoglobulin M (IgM) antibody tests or nonstructural protein 1 antigen tests and IgM antibody tests.
• Ensure timely reporting of dengue cases to public health authorities.
• Promote mosquito bite prevention measures among people living in or visiting areas with frequent or continuous dengue transmission.

Roughly one in four dengue virus infections are symptomatic and can be mild or severe. Symptoms begin after an incubation period of about 5-7 days.

Symptoms include fever accompanied by nonspecific signs and symptoms such as nausea, vomiting, rash, muscle aches, joint pain, bone pain, pain behind the eyes, headache, or low white blood cell counts.
 

Disease Progression

Warning signs that may predict progression to severe disease include abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy or restlessness, and progressive increase in hematocrit or liver enlargement.

One in 20 people with symptomatic dengue will develop severe disease, with bleeding, shock, or respiratory distress caused by plasma leakage or end-organ impairment.

Infants aged a year or younger, pregnant people, adults aged 65 years or older, people with certain medical conditions, and those with previous dengue infections are at increased risk for severe dengue.

“Healthcare providers should be prepared to recognize, diagnose, manage, and report dengue cases to health authorities; public health partners should investigate cases and disseminate clear prevention messages to the public,” the alert stated.

The CDC is actively implementing several strategies to address the increase in cases of dengue in the United States. In early April, the agency launched a program-led emergency response and is providing monthly situational updates on dengue to partners, stakeholders, and jurisdictions.

The CDC is also expanding laboratory capacity to improve laboratory testing approaches; collaborating with state, tribal, local, and territorial health departments to strengthen dengue surveillance and recommend prevention strategies; and working to educate the public on dengue prevention.

A version of this article first appeared on Medscape.com.

The relatively new antibiotic cefiderocol given in the form of eye drops may be a way to combat a type of ocular infection that broke out in the United States last year, according to research presented at the 2024 annual meeting of the Association for Research in Vision and Ophthalmology (ARVO).

The infections, linked to contaminated bottles of artificial tears, were detected in 81 patients in 18 states. The outbreak led to loss of vision in 14 patients, surgical removal of the eyeball in four patients, and four deaths, according to health officials. 

An extensively drug-resistant strain of Pseudomonas aeruginosa that had not previously been reported in the country caused the infections. Scientists cautioned last year that the bacteria potentially could spread from person to person. 

At ARVO on May 6, Eric G. Romanowski, MS, research director of the Charles T. Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, described studies that his lab conducted evaluating topical cefiderocol as a potential treatment option for these infections (Abstract 2095).

Investigators had found that the bacterial strain was susceptible to this medication, which was approved by the US Food and Drug Administration in 2019 as a treatment for complicated urinary tract infections. But the antibiotic had not been tested as an eye drop.

“We showed that the ‘Trojan-horse’ antibiotic, cefiderocol … was non-toxic and effective against the highly resistant outbreak strain in an experimental model of infection,” Dr. Romanowski and co–lead investigator Robert M. Q. Shanks, PhD, said in a statement about their research. “These results demonstrate that topical cefiderocol could be a new weapon in the ophthalmologist’s arsenal for the treatment of corneal infections caused by highly antibiotic-resistant Pseudomonas aeruginosa.”
 

Experimental Models

Dr. Romanowski’s group, with colleagues at the Geisel School of Medicine at Dartmouth University, Hanover, New Hampshire, used minimum inhibitory concentration testing to evaluate the effectiveness of cefiderocol against 135 isolates from eye infections. They also tested ocular toxicity and antibiotic efficacy of cefiderocol eye drops in a rabbit model of keratitis caused by the bacterial strain.

Cefiderocol was “well tolerated on rabbit corneas,” they reported. It also was effective in vitro against the isolates and in vivo in the rabbit model of keratitis.

They first published their findings as a preprint in September 2023 and then in Ophthalmology Science in December.

 

A ‘Duty to the Profession’

Their paper noted that “there is no current consensus as to the most effective antimicrobial strategy to deal with” extensively drug-resistant keratitis.

During the outbreak, clinicians tried various treatment regimens, with mixed results. In one case, a combination of intravenous cefiderocol and other topical and oral medications appeared to be successful.

Dr. Romanowski’s team decided to test cefiderocol drops with their own resources “as a duty to the profession,” he said. “Not many labs do these types of studies.”

“We would like to see further development of this antibiotic for potential use,” Dr. Romanowski added. “It would be up to any individual clinician to determine whether to use this antibiotic in an emergency situation.”

A version of this article appeared on Medscape.com.

The relatively new antibiotic cefiderocol given in the form of eye drops may be a way to combat a type of ocular infection that broke out in the United States last year, according to research presented at the 2024 annual meeting of the Association for Research in Vision and Ophthalmology (ARVO).

The infections, linked to contaminated bottles of artificial tears, were detected in 81 patients in 18 states. The outbreak led to loss of vision in 14 patients, surgical removal of the eyeball in four patients, and four deaths, according to health officials. 

An extensively drug-resistant strain of Pseudomonas aeruginosa that had not previously been reported in the country caused the infections. Scientists cautioned last year that the bacteria potentially could spread from person to person. 

At ARVO on May 6, Eric G. Romanowski, MS, research director of the Charles T. Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, described studies that his lab conducted evaluating topical cefiderocol as a potential treatment option for these infections (Abstract 2095).

Investigators had found that the bacterial strain was susceptible to this medication, which was approved by the US Food and Drug Administration in 2019 as a treatment for complicated urinary tract infections. But the antibiotic had not been tested as an eye drop.

“We showed that the ‘Trojan-horse’ antibiotic, cefiderocol … was non-toxic and effective against the highly resistant outbreak strain in an experimental model of infection,” Dr. Romanowski and co–lead investigator Robert M. Q. Shanks, PhD, said in a statement about their research. “These results demonstrate that topical cefiderocol could be a new weapon in the ophthalmologist’s arsenal for the treatment of corneal infections caused by highly antibiotic-resistant Pseudomonas aeruginosa.”
 

Experimental Models

Dr. Romanowski’s group, with colleagues at the Geisel School of Medicine at Dartmouth University, Hanover, New Hampshire, used minimum inhibitory concentration testing to evaluate the effectiveness of cefiderocol against 135 isolates from eye infections. They also tested ocular toxicity and antibiotic efficacy of cefiderocol eye drops in a rabbit model of keratitis caused by the bacterial strain.

Cefiderocol was “well tolerated on rabbit corneas,” they reported. It also was effective in vitro against the isolates and in vivo in the rabbit model of keratitis.

They first published their findings as a preprint in September 2023 and then in Ophthalmology Science in December.

 

A ‘Duty to the Profession’

Their paper noted that “there is no current consensus as to the most effective antimicrobial strategy to deal with” extensively drug-resistant keratitis.

During the outbreak, clinicians tried various treatment regimens, with mixed results. In one case, a combination of intravenous cefiderocol and other topical and oral medications appeared to be successful.

Dr. Romanowski’s team decided to test cefiderocol drops with their own resources “as a duty to the profession,” he said. “Not many labs do these types of studies.”

“We would like to see further development of this antibiotic for potential use,” Dr. Romanowski added. “It would be up to any individual clinician to determine whether to use this antibiotic in an emergency situation.”

A version of this article appeared on Medscape.com.

The relatively new antibiotic cefiderocol given in the form of eye drops may be a way to combat a type of ocular infection that broke out in the United States last year, according to research presented at the 2024 annual meeting of the Association for Research in Vision and Ophthalmology (ARVO).

The infections, linked to contaminated bottles of artificial tears, were detected in 81 patients in 18 states. The outbreak led to loss of vision in 14 patients, surgical removal of the eyeball in four patients, and four deaths, according to health officials. 

An extensively drug-resistant strain of Pseudomonas aeruginosa that had not previously been reported in the country caused the infections. Scientists cautioned last year that the bacteria potentially could spread from person to person. 

At ARVO on May 6, Eric G. Romanowski, MS, research director of the Charles T. Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, described studies that his lab conducted evaluating topical cefiderocol as a potential treatment option for these infections (Abstract 2095).

Investigators had found that the bacterial strain was susceptible to this medication, which was approved by the US Food and Drug Administration in 2019 as a treatment for complicated urinary tract infections. But the antibiotic had not been tested as an eye drop.

“We showed that the ‘Trojan-horse’ antibiotic, cefiderocol … was non-toxic and effective against the highly resistant outbreak strain in an experimental model of infection,” Dr. Romanowski and co–lead investigator Robert M. Q. Shanks, PhD, said in a statement about their research. “These results demonstrate that topical cefiderocol could be a new weapon in the ophthalmologist’s arsenal for the treatment of corneal infections caused by highly antibiotic-resistant Pseudomonas aeruginosa.”
 

Experimental Models

Dr. Romanowski’s group, with colleagues at the Geisel School of Medicine at Dartmouth University, Hanover, New Hampshire, used minimum inhibitory concentration testing to evaluate the effectiveness of cefiderocol against 135 isolates from eye infections. They also tested ocular toxicity and antibiotic efficacy of cefiderocol eye drops in a rabbit model of keratitis caused by the bacterial strain.

Cefiderocol was “well tolerated on rabbit corneas,” they reported. It also was effective in vitro against the isolates and in vivo in the rabbit model of keratitis.

They first published their findings as a preprint in September 2023 and then in Ophthalmology Science in December.

 

A ‘Duty to the Profession’

Their paper noted that “there is no current consensus as to the most effective antimicrobial strategy to deal with” extensively drug-resistant keratitis.

During the outbreak, clinicians tried various treatment regimens, with mixed results. In one case, a combination of intravenous cefiderocol and other topical and oral medications appeared to be successful.

Dr. Romanowski’s team decided to test cefiderocol drops with their own resources “as a duty to the profession,” he said. “Not many labs do these types of studies.”

“We would like to see further development of this antibiotic for potential use,” Dr. Romanowski added. “It would be up to any individual clinician to determine whether to use this antibiotic in an emergency situation.”

A version of this article appeared on Medscape.com.

The current tetravalent dengue vaccine TAK-003, from the Japanese laboratory Takeda, is not likely to control the ongoing epidemic, according to the Pan American Health Organization (PAHO). The organization emphasized the need to better understand the vaccine’s effectiveness against different serotypes and its safety under real-world clinical conditions.

The Americas are experiencing a record increase in dengue cases. Three times as many cases have been identified during 2024 (3.5 million) than were reported for the same period in 2023. 

“The vaccine we have available will not curb the dengue epidemic; it should be used complementarily with other actions. The most important actions are field operations, vector control, prevention, and education,” said Daniel Salas, MD, executive manager of the PAHO Comprehensive Immunization Program, during a press conference on March 28.

“The vaccines we currently have are not the best response to reduce transmission and prevent deaths,” added Jarbas Barbosa, MD, PhD, PAHO’s director. The fatality rate remains below 0.05%, but this figure could be hard to maintain if the situation becomes more uncontrolled.

The TAK-003 regimen consists of two doses with a 3-month interval between applications, so “it is not a tool to control transmission at this moment. Studies have shown that only 8 years of [population-level] vaccination would have a significant impact on dengue transmission,” said Dr. Barbosa.

A new vaccine developed in Brazil in partnership with the company MSD, Butantan-DV, is in phase 3 trials and has the advantage of being a single-dose application, which could facilitate its use in situations with accelerated transmission. “But this vaccine will likely only be available in 2025,” said Dr. Barbosa.

PAHO officials also highlighted the need to better characterize the vaccine’s effectiveness and safety in the real world. They observed, for example, that when TAK-003 was investigated, the circulation of dengue serotype 3 was almost nonexistent, so the efficacy data against that serotype “are very limited.”

“The producer, Takeda, has very limited production capacity. Brazil is the country that uses this vaccine the most, followed by Argentina. Given that these countries have a good epidemiological surveillance system and adverse effect registration, they can conduct studies on how the vaccine performs in real life, which will greatly increase our knowledge about it. For example, we will see its effectiveness against serotype 3,” said Dr. Barbosa.

The PAHO Technical Advisory Group (TAG) on vaccine-preventable diseases recommended that any country using these vaccines have surveillance systems in place because it is important to promptly report and investigate any adverse events, said Dr. Salas. The organization also suggested that vaccination should ideally be administered in a “more controlled environment,” a phase 4 study, “to complete the safety and efficacy profile, especially in those who have not had dengue before and for dengue 3 and 4,” said Dr. Salas in response to a question from this news organization.

“People cannot expect that just because they were vaccinated, they will not get dengue. The vaccine has limited reach,” he emphasized.

Other research strategies for vector control, such as the use of the Wolbachia bacteria and mosquito sterilization, are future strategies and “not tools to control this outbreak,” noted Sylvain Aldighieri, MD, director of the Department of Prevention, Control, and Elimination of Transmissible Diseases at PAHO.

In his opening remarks, Dr. Barbosa urged the intensification of efforts with tools that are already available. These approaches include eliminating mosquito breeding sites (“80% are in or near homes”) and protecting against mosquito bites, preparing health services for early diagnosis and timely clinical management, and educating the population about dengue symptoms so they seek medical attention immediately.

Although dengue is increasing throughout Latin America and the Caribbean, the most affected countries are Brazil (83%), Paraguay (5.3%), and Argentina (3.7%), which account for 92% of the cases and 87% of the deaths, PAHO reported.

This story was translated from the Medscape Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com .

The current tetravalent dengue vaccine TAK-003, from the Japanese laboratory Takeda, is not likely to control the ongoing epidemic, according to the Pan American Health Organization (PAHO). The organization emphasized the need to better understand the vaccine’s effectiveness against different serotypes and its safety under real-world clinical conditions.

The Americas are experiencing a record increase in dengue cases. Three times as many cases have been identified during 2024 (3.5 million) than were reported for the same period in 2023. 

“The vaccine we have available will not curb the dengue epidemic; it should be used complementarily with other actions. The most important actions are field operations, vector control, prevention, and education,” said Daniel Salas, MD, executive manager of the PAHO Comprehensive Immunization Program, during a press conference on March 28.

“The vaccines we currently have are not the best response to reduce transmission and prevent deaths,” added Jarbas Barbosa, MD, PhD, PAHO’s director. The fatality rate remains below 0.05%, but this figure could be hard to maintain if the situation becomes more uncontrolled.

The TAK-003 regimen consists of two doses with a 3-month interval between applications, so “it is not a tool to control transmission at this moment. Studies have shown that only 8 years of [population-level] vaccination would have a significant impact on dengue transmission,” said Dr. Barbosa.

A new vaccine developed in Brazil in partnership with the company MSD, Butantan-DV, is in phase 3 trials and has the advantage of being a single-dose application, which could facilitate its use in situations with accelerated transmission. “But this vaccine will likely only be available in 2025,” said Dr. Barbosa.

PAHO officials also highlighted the need to better characterize the vaccine’s effectiveness and safety in the real world. They observed, for example, that when TAK-003 was investigated, the circulation of dengue serotype 3 was almost nonexistent, so the efficacy data against that serotype “are very limited.”

“The producer, Takeda, has very limited production capacity. Brazil is the country that uses this vaccine the most, followed by Argentina. Given that these countries have a good epidemiological surveillance system and adverse effect registration, they can conduct studies on how the vaccine performs in real life, which will greatly increase our knowledge about it. For example, we will see its effectiveness against serotype 3,” said Dr. Barbosa.

The PAHO Technical Advisory Group (TAG) on vaccine-preventable diseases recommended that any country using these vaccines have surveillance systems in place because it is important to promptly report and investigate any adverse events, said Dr. Salas. The organization also suggested that vaccination should ideally be administered in a “more controlled environment,” a phase 4 study, “to complete the safety and efficacy profile, especially in those who have not had dengue before and for dengue 3 and 4,” said Dr. Salas in response to a question from this news organization.

“People cannot expect that just because they were vaccinated, they will not get dengue. The vaccine has limited reach,” he emphasized.

Other research strategies for vector control, such as the use of the Wolbachia bacteria and mosquito sterilization, are future strategies and “not tools to control this outbreak,” noted Sylvain Aldighieri, MD, director of the Department of Prevention, Control, and Elimination of Transmissible Diseases at PAHO.

In his opening remarks, Dr. Barbosa urged the intensification of efforts with tools that are already available. These approaches include eliminating mosquito breeding sites (“80% are in or near homes”) and protecting against mosquito bites, preparing health services for early diagnosis and timely clinical management, and educating the population about dengue symptoms so they seek medical attention immediately.

Although dengue is increasing throughout Latin America and the Caribbean, the most affected countries are Brazil (83%), Paraguay (5.3%), and Argentina (3.7%), which account for 92% of the cases and 87% of the deaths, PAHO reported.

This story was translated from the Medscape Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com .

The current tetravalent dengue vaccine TAK-003, from the Japanese laboratory Takeda, is not likely to control the ongoing epidemic, according to the Pan American Health Organization (PAHO). The organization emphasized the need to better understand the vaccine’s effectiveness against different serotypes and its safety under real-world clinical conditions.

The Americas are experiencing a record increase in dengue cases. Three times as many cases have been identified during 2024 (3.5 million) than were reported for the same period in 2023. 

“The vaccine we have available will not curb the dengue epidemic; it should be used complementarily with other actions. The most important actions are field operations, vector control, prevention, and education,” said Daniel Salas, MD, executive manager of the PAHO Comprehensive Immunization Program, during a press conference on March 28.

“The vaccines we currently have are not the best response to reduce transmission and prevent deaths,” added Jarbas Barbosa, MD, PhD, PAHO’s director. The fatality rate remains below 0.05%, but this figure could be hard to maintain if the situation becomes more uncontrolled.

The TAK-003 regimen consists of two doses with a 3-month interval between applications, so “it is not a tool to control transmission at this moment. Studies have shown that only 8 years of [population-level] vaccination would have a significant impact on dengue transmission,” said Dr. Barbosa.

A new vaccine developed in Brazil in partnership with the company MSD, Butantan-DV, is in phase 3 trials and has the advantage of being a single-dose application, which could facilitate its use in situations with accelerated transmission. “But this vaccine will likely only be available in 2025,” said Dr. Barbosa.

PAHO officials also highlighted the need to better characterize the vaccine’s effectiveness and safety in the real world. They observed, for example, that when TAK-003 was investigated, the circulation of dengue serotype 3 was almost nonexistent, so the efficacy data against that serotype “are very limited.”

“The producer, Takeda, has very limited production capacity. Brazil is the country that uses this vaccine the most, followed by Argentina. Given that these countries have a good epidemiological surveillance system and adverse effect registration, they can conduct studies on how the vaccine performs in real life, which will greatly increase our knowledge about it. For example, we will see its effectiveness against serotype 3,” said Dr. Barbosa.

The PAHO Technical Advisory Group (TAG) on vaccine-preventable diseases recommended that any country using these vaccines have surveillance systems in place because it is important to promptly report and investigate any adverse events, said Dr. Salas. The organization also suggested that vaccination should ideally be administered in a “more controlled environment,” a phase 4 study, “to complete the safety and efficacy profile, especially in those who have not had dengue before and for dengue 3 and 4,” said Dr. Salas in response to a question from this news organization.

“People cannot expect that just because they were vaccinated, they will not get dengue. The vaccine has limited reach,” he emphasized.

Other research strategies for vector control, such as the use of the Wolbachia bacteria and mosquito sterilization, are future strategies and “not tools to control this outbreak,” noted Sylvain Aldighieri, MD, director of the Department of Prevention, Control, and Elimination of Transmissible Diseases at PAHO.

In his opening remarks, Dr. Barbosa urged the intensification of efforts with tools that are already available. These approaches include eliminating mosquito breeding sites (“80% are in or near homes”) and protecting against mosquito bites, preparing health services for early diagnosis and timely clinical management, and educating the population about dengue symptoms so they seek medical attention immediately.

Although dengue is increasing throughout Latin America and the Caribbean, the most affected countries are Brazil (83%), Paraguay (5.3%), and Argentina (3.7%), which account for 92% of the cases and 87% of the deaths, PAHO reported.

This story was translated from the Medscape Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com .

Thanks to decades of successful vector control strategies, vector-borne transmission of Chagas disease has significantly decreased in many regions. Oral ingestion of Trypanosoma cruzi through contaminated food and beverages, however, is increasing. Unlike vector transmission, oral transmission of Chagas disease entails high lethality in pediatric and adult populations.

“The oral transmission of Chagas disease is becoming a much more recognized route, and it is crucial to understand that people can die from this type of transmission,” Norman L. Beatty, MD, assistant professor of infectious diseases and global medicine at the University of Florida College of Medicine in Gainesville, Florida, told this news organization. Dr. Beatty is the lead author of a recent article on the subject.

In regions where the parasite circulates in the environment, people are consuming foods, fruit juices, and possibly wild animal meat that may be contaminated. “As we experience changes in our environment and in the way we consume food, it is crucial to consider how food preparation is carried out in areas where T cruzi transmission occurs in the environment,” said Dr. Beatty. “And as organic farming methods without insecticides become increasingly common, more research is needed in these areas, both in Latin America and in the United States, to understand if oral transmission of T cruzi is occurring.”

In the Amazon basin, foodborne transmission is already the leading cause of acute Chagas disease. It has been described in Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, and Venezuela.

Dr. Beatty’s colleagues recently treated a Brazilian patient at the hospital in Florida. “He came to our hospital very ill, with acute myocarditis after consuming contaminated açaí.” Clarifying that there is widespread awareness about oral transmission in Brazil, he stated, “We are concerned that it may not be recognized in other areas of Latin America.”

Mexico and regions of Central America have little to no information on oral transmission, but it is likely occurring, and cases may be going undetected in the region, said Dr. Beatty.

He investigated the issue in Colombia as part of an international collaboration involving the University of Antioquia, aiming to find ways to mitigate oral transmission and create a model that can be used throughout Latin America and the United States. For the Colombia study, they reviewed all cases reported to the Ministry of Health and Social Protection, and oral transmission turned out to be more common than the research group expected. “Still, I imagine that in certain areas with limited resources…there are many more cases that are not being reported.

“A myth I would like to dispel is that Chagas disease is not being transmitted in the United States,” Dr. Beatty added. He mentioned that at least 30 American states have vectors, and in Florida, it was documented that triatomines invaded homes and bit residents. In addition, 30% of these insects are infected with T cruzi. Research is underway to determine whether Floridians are becoming infected and if they are also at risk of contracting Chagas disease orally, said Dr. Beatty. “In the United States, we know very little about how many people are infected and what the infection routes are. Much more research is needed.”

Roberto Chuit, MD, PhD, a doctor in public health and an external consultant for the Pan American Health Organization (PAHO), agreed that this route of food contamination, which occurs because of vector-borne parasites, was until recently masked or hidden by the predominance of vector presence. Just as it began to gain importance as other transmission routes were controlled, “it now has extremely high importance in the Americas, as does vertical transmission,” he said.

In 2023, more than 50 years after the first description of oral transmission, the PAHO expert meeting proposed to alert health services and the broader community about the severity and potential lethality of oral Chagas disease outbreaks to elicit immediate responses and mitigation measures. The body also proposed conducting studies to provide detailed information on the contamination source and the wild vectors present in oral transmission foci.
 

Unique Clinical Manifestations

The exacerbated signs and symptoms of oral infection (see sidebar) are attributed to the high parasite loads in contaminated food and beverages. A single crushed triatomine along with a food or beverage harboring T cruzi can contain an estimated 600,000 metacyclic trypomastigotes, compared with 3000-4000 per µL when infection occurs by triatomine fecal matter. The robust systemic immune response observed in patients with acute oral Chagas disease is thought to result from more efficient transmission after penetration through the oral, pharyngeal, and gastric mucosae.
 

Seven Things to Know About Orally Transmitted Chagas Disease

1. It presents with exacerbated symptoms and rapid disease progression in immunocompetent individuals. This presentation is not common in vector-borne, congenital, or transfusion-related transmission. It can cause fulminant myocarditis and heart failure, meningoencephalitis, or potentially fatal shock due to parasitemia.

2. Most patients (71%-100%) with acute oral Chagas present with fever.

3. Electrocardiographic abnormalities, specifically ventricular depolarization alterations and pericardial involvement, are observed in most patients.

4. Facial edema, which typically affects the entire face and parts of the lips, is present in 57%-100% of patients with acute oral Chagas disease. In those with acute symptoms from vector transmission, unilateral periorbital swelling (Romaña’s sign) is more common.

5. Other notable systemic symptoms include edema of the lower extremities, myalgia, generalized lymphadenopathy, abdominal discomfort, dyspnea, vomiting, diarrhea, hepatomegaly, splenomegaly, headache, chest pain, cutaneous erythematous rash, jaundice, arthralgia, epistaxis, hematemesis, melena, and palpitations.

6. The incubation period after oral ingestion of products contaminated with Trypanosoma cruzi is approximately 3-22 days, in contrast to 4-15 days for vector-borne transmission and 8-160 days for transfusion and transplant-related transmission.

7. Patients need antiparasitic drugs immediately.
 

Thinking Epidemiologically

Dr. Chuit recalled that suspicion of food contamination should be based on epidemiology, especially in outbreaks affecting several people and in regions where Chagas vectors have been described. Sometimes, however, a single careless tourist consumes contaminated products.

“The difficulty is that many times it is not considered, and if it is not considered, the search for the parasite is not requested,” said Dr. Chuit. He added that it is common for the professional to consider Chagas disease only if viral and bacterial isolation tests are negative. Clinicians sometimes consider Chagas disease because the patient has not responded to regular treatments for other causes, such as antibiotics and hydration.

Epidemiology is important, especially when Chagas disease is diagnosed in groups or a family, because they are usually not isolated cases but outbreaks of 3-40 cases, according to Dr. Chuit. “Under these conditions, it must be quickly considered…that this parasite may be involved.”

One of the difficulties is that the source of these oral transmissions is not recognized most of the time. In general, the sources are usually foods that are more likely to be contaminated by insects or insect feces, such as orange juice or sugarcane. But in fact, any food or beverage left unattended could be contaminated by vectors or possible secretions from infected marsupial odoriferous glands.

An analysis of 32 outbreaks from 1965 to 2022 showed that the main foods involved in oral transmission were homemade fruit juices. But different vector species were identified, and the reservoirs were mainly dogs, rodents, and large American opossums (Didelphis).

The largest oral Chagas outbreak was linked to the consumption of contaminated guava juice in a primary school in Caracas, Venezuela. Nonindustrially produced açaí is a common source of orally acquired Chagas disease in Brazil. In Colombia, Chagas disease has been associated with the consumption of palm wine, sugar cane, and tangerine juice. Other oral transmission routes include consuming meat from wild animals and ingesting blood from infected armadillos, which is related to a traditional medicine practice.
 

Deadly Yet Easily Treatable

In the outbreak of 119 confirmed and suspected cases in Venezuela, 20.3% required hospitalization, and a 5-year-old child died of acute myocarditis. These percentages differ from those reported in vector transmission, which is asymptomatic in the acute phase for 95%-99% of cases or will only develop a mild febrile illness that resolves on its own.

“Not all cases will present as severe, because depending on the inoculum, there may be individuals with subclinical situations. But any food poisoning that occurs in endemic areas, where food is not properly controlled, and these street foods are associated with processes in jungle areas, raises the possibility that T cruzi is involved and should be considered as a differential diagnosis,» noted Dr. Chuit. “The treatment is highly effective, and people recover quickly.”

“The most important thing about oral transmission of Chagas is that someone infected in this way needs antiparasitic drugs immediately. We can cure them if we treat them immediately,” said Dr. Beatty, adding that treatment is sometimes delayed due to lack of access to appropriate antiparasitic drugs. “Here in the United States and in Latin America, it is quite common for healthcare professionals not to understand the differences between vector, vertical, and oral transmission. By not treating these patients, they become ill quickly.”

Dr. Beatty and Dr. Chuit declared no relevant financial conflicts of interest.

This story was translated from the Medscape Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Thanks to decades of successful vector control strategies, vector-borne transmission of Chagas disease has significantly decreased in many regions. Oral ingestion of Trypanosoma cruzi through contaminated food and beverages, however, is increasing. Unlike vector transmission, oral transmission of Chagas disease entails high lethality in pediatric and adult populations.

“The oral transmission of Chagas disease is becoming a much more recognized route, and it is crucial to understand that people can die from this type of transmission,” Norman L. Beatty, MD, assistant professor of infectious diseases and global medicine at the University of Florida College of Medicine in Gainesville, Florida, told this news organization. Dr. Beatty is the lead author of a recent article on the subject.

In regions where the parasite circulates in the environment, people are consuming foods, fruit juices, and possibly wild animal meat that may be contaminated. “As we experience changes in our environment and in the way we consume food, it is crucial to consider how food preparation is carried out in areas where T cruzi transmission occurs in the environment,” said Dr. Beatty. “And as organic farming methods without insecticides become increasingly common, more research is needed in these areas, both in Latin America and in the United States, to understand if oral transmission of T cruzi is occurring.”

In the Amazon basin, foodborne transmission is already the leading cause of acute Chagas disease. It has been described in Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, and Venezuela.

Dr. Beatty’s colleagues recently treated a Brazilian patient at the hospital in Florida. “He came to our hospital very ill, with acute myocarditis after consuming contaminated açaí.” Clarifying that there is widespread awareness about oral transmission in Brazil, he stated, “We are concerned that it may not be recognized in other areas of Latin America.”

Mexico and regions of Central America have little to no information on oral transmission, but it is likely occurring, and cases may be going undetected in the region, said Dr. Beatty.

He investigated the issue in Colombia as part of an international collaboration involving the University of Antioquia, aiming to find ways to mitigate oral transmission and create a model that can be used throughout Latin America and the United States. For the Colombia study, they reviewed all cases reported to the Ministry of Health and Social Protection, and oral transmission turned out to be more common than the research group expected. “Still, I imagine that in certain areas with limited resources…there are many more cases that are not being reported.

“A myth I would like to dispel is that Chagas disease is not being transmitted in the United States,” Dr. Beatty added. He mentioned that at least 30 American states have vectors, and in Florida, it was documented that triatomines invaded homes and bit residents. In addition, 30% of these insects are infected with T cruzi. Research is underway to determine whether Floridians are becoming infected and if they are also at risk of contracting Chagas disease orally, said Dr. Beatty. “In the United States, we know very little about how many people are infected and what the infection routes are. Much more research is needed.”

Roberto Chuit, MD, PhD, a doctor in public health and an external consultant for the Pan American Health Organization (PAHO), agreed that this route of food contamination, which occurs because of vector-borne parasites, was until recently masked or hidden by the predominance of vector presence. Just as it began to gain importance as other transmission routes were controlled, “it now has extremely high importance in the Americas, as does vertical transmission,” he said.

In 2023, more than 50 years after the first description of oral transmission, the PAHO expert meeting proposed to alert health services and the broader community about the severity and potential lethality of oral Chagas disease outbreaks to elicit immediate responses and mitigation measures. The body also proposed conducting studies to provide detailed information on the contamination source and the wild vectors present in oral transmission foci.
 

Unique Clinical Manifestations

The exacerbated signs and symptoms of oral infection (see sidebar) are attributed to the high parasite loads in contaminated food and beverages. A single crushed triatomine along with a food or beverage harboring T cruzi can contain an estimated 600,000 metacyclic trypomastigotes, compared with 3000-4000 per µL when infection occurs by triatomine fecal matter. The robust systemic immune response observed in patients with acute oral Chagas disease is thought to result from more efficient transmission after penetration through the oral, pharyngeal, and gastric mucosae.
 

Seven Things to Know About Orally Transmitted Chagas Disease

1. It presents with exacerbated symptoms and rapid disease progression in immunocompetent individuals. This presentation is not common in vector-borne, congenital, or transfusion-related transmission. It can cause fulminant myocarditis and heart failure, meningoencephalitis, or potentially fatal shock due to parasitemia.

2. Most patients (71%-100%) with acute oral Chagas present with fever.

3. Electrocardiographic abnormalities, specifically ventricular depolarization alterations and pericardial involvement, are observed in most patients.

4. Facial edema, which typically affects the entire face and parts of the lips, is present in 57%-100% of patients with acute oral Chagas disease. In those with acute symptoms from vector transmission, unilateral periorbital swelling (Romaña’s sign) is more common.

5. Other notable systemic symptoms include edema of the lower extremities, myalgia, generalized lymphadenopathy, abdominal discomfort, dyspnea, vomiting, diarrhea, hepatomegaly, splenomegaly, headache, chest pain, cutaneous erythematous rash, jaundice, arthralgia, epistaxis, hematemesis, melena, and palpitations.

6. The incubation period after oral ingestion of products contaminated with Trypanosoma cruzi is approximately 3-22 days, in contrast to 4-15 days for vector-borne transmission and 8-160 days for transfusion and transplant-related transmission.

7. Patients need antiparasitic drugs immediately.
 

Thinking Epidemiologically

Dr. Chuit recalled that suspicion of food contamination should be based on epidemiology, especially in outbreaks affecting several people and in regions where Chagas vectors have been described. Sometimes, however, a single careless tourist consumes contaminated products.

“The difficulty is that many times it is not considered, and if it is not considered, the search for the parasite is not requested,” said Dr. Chuit. He added that it is common for the professional to consider Chagas disease only if viral and bacterial isolation tests are negative. Clinicians sometimes consider Chagas disease because the patient has not responded to regular treatments for other causes, such as antibiotics and hydration.

Epidemiology is important, especially when Chagas disease is diagnosed in groups or a family, because they are usually not isolated cases but outbreaks of 3-40 cases, according to Dr. Chuit. “Under these conditions, it must be quickly considered…that this parasite may be involved.”

One of the difficulties is that the source of these oral transmissions is not recognized most of the time. In general, the sources are usually foods that are more likely to be contaminated by insects or insect feces, such as orange juice or sugarcane. But in fact, any food or beverage left unattended could be contaminated by vectors or possible secretions from infected marsupial odoriferous glands.

An analysis of 32 outbreaks from 1965 to 2022 showed that the main foods involved in oral transmission were homemade fruit juices. But different vector species were identified, and the reservoirs were mainly dogs, rodents, and large American opossums (Didelphis).

The largest oral Chagas outbreak was linked to the consumption of contaminated guava juice in a primary school in Caracas, Venezuela. Nonindustrially produced açaí is a common source of orally acquired Chagas disease in Brazil. In Colombia, Chagas disease has been associated with the consumption of palm wine, sugar cane, and tangerine juice. Other oral transmission routes include consuming meat from wild animals and ingesting blood from infected armadillos, which is related to a traditional medicine practice.
 

Deadly Yet Easily Treatable

In the outbreak of 119 confirmed and suspected cases in Venezuela, 20.3% required hospitalization, and a 5-year-old child died of acute myocarditis. These percentages differ from those reported in vector transmission, which is asymptomatic in the acute phase for 95%-99% of cases or will only develop a mild febrile illness that resolves on its own.

“Not all cases will present as severe, because depending on the inoculum, there may be individuals with subclinical situations. But any food poisoning that occurs in endemic areas, where food is not properly controlled, and these street foods are associated with processes in jungle areas, raises the possibility that T cruzi is involved and should be considered as a differential diagnosis,» noted Dr. Chuit. “The treatment is highly effective, and people recover quickly.”

“The most important thing about oral transmission of Chagas is that someone infected in this way needs antiparasitic drugs immediately. We can cure them if we treat them immediately,” said Dr. Beatty, adding that treatment is sometimes delayed due to lack of access to appropriate antiparasitic drugs. “Here in the United States and in Latin America, it is quite common for healthcare professionals not to understand the differences between vector, vertical, and oral transmission. By not treating these patients, they become ill quickly.”

Dr. Beatty and Dr. Chuit declared no relevant financial conflicts of interest.

This story was translated from the Medscape Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Thanks to decades of successful vector control strategies, vector-borne transmission of Chagas disease has significantly decreased in many regions. Oral ingestion of Trypanosoma cruzi through contaminated food and beverages, however, is increasing. Unlike vector transmission, oral transmission of Chagas disease entails high lethality in pediatric and adult populations.

“The oral transmission of Chagas disease is becoming a much more recognized route, and it is crucial to understand that people can die from this type of transmission,” Norman L. Beatty, MD, assistant professor of infectious diseases and global medicine at the University of Florida College of Medicine in Gainesville, Florida, told this news organization. Dr. Beatty is the lead author of a recent article on the subject.

In regions where the parasite circulates in the environment, people are consuming foods, fruit juices, and possibly wild animal meat that may be contaminated. “As we experience changes in our environment and in the way we consume food, it is crucial to consider how food preparation is carried out in areas where T cruzi transmission occurs in the environment,” said Dr. Beatty. “And as organic farming methods without insecticides become increasingly common, more research is needed in these areas, both in Latin America and in the United States, to understand if oral transmission of T cruzi is occurring.”

In the Amazon basin, foodborne transmission is already the leading cause of acute Chagas disease. It has been described in Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, and Venezuela.

Dr. Beatty’s colleagues recently treated a Brazilian patient at the hospital in Florida. “He came to our hospital very ill, with acute myocarditis after consuming contaminated açaí.” Clarifying that there is widespread awareness about oral transmission in Brazil, he stated, “We are concerned that it may not be recognized in other areas of Latin America.”

Mexico and regions of Central America have little to no information on oral transmission, but it is likely occurring, and cases may be going undetected in the region, said Dr. Beatty.

He investigated the issue in Colombia as part of an international collaboration involving the University of Antioquia, aiming to find ways to mitigate oral transmission and create a model that can be used throughout Latin America and the United States. For the Colombia study, they reviewed all cases reported to the Ministry of Health and Social Protection, and oral transmission turned out to be more common than the research group expected. “Still, I imagine that in certain areas with limited resources…there are many more cases that are not being reported.

“A myth I would like to dispel is that Chagas disease is not being transmitted in the United States,” Dr. Beatty added. He mentioned that at least 30 American states have vectors, and in Florida, it was documented that triatomines invaded homes and bit residents. In addition, 30% of these insects are infected with T cruzi. Research is underway to determine whether Floridians are becoming infected and if they are also at risk of contracting Chagas disease orally, said Dr. Beatty. “In the United States, we know very little about how many people are infected and what the infection routes are. Much more research is needed.”

Roberto Chuit, MD, PhD, a doctor in public health and an external consultant for the Pan American Health Organization (PAHO), agreed that this route of food contamination, which occurs because of vector-borne parasites, was until recently masked or hidden by the predominance of vector presence. Just as it began to gain importance as other transmission routes were controlled, “it now has extremely high importance in the Americas, as does vertical transmission,” he said.

In 2023, more than 50 years after the first description of oral transmission, the PAHO expert meeting proposed to alert health services and the broader community about the severity and potential lethality of oral Chagas disease outbreaks to elicit immediate responses and mitigation measures. The body also proposed conducting studies to provide detailed information on the contamination source and the wild vectors present in oral transmission foci.
 

Unique Clinical Manifestations

The exacerbated signs and symptoms of oral infection (see sidebar) are attributed to the high parasite loads in contaminated food and beverages. A single crushed triatomine along with a food or beverage harboring T cruzi can contain an estimated 600,000 metacyclic trypomastigotes, compared with 3000-4000 per µL when infection occurs by triatomine fecal matter. The robust systemic immune response observed in patients with acute oral Chagas disease is thought to result from more efficient transmission after penetration through the oral, pharyngeal, and gastric mucosae.
 

Seven Things to Know About Orally Transmitted Chagas Disease

1. It presents with exacerbated symptoms and rapid disease progression in immunocompetent individuals. This presentation is not common in vector-borne, congenital, or transfusion-related transmission. It can cause fulminant myocarditis and heart failure, meningoencephalitis, or potentially fatal shock due to parasitemia.

2. Most patients (71%-100%) with acute oral Chagas present with fever.

3. Electrocardiographic abnormalities, specifically ventricular depolarization alterations and pericardial involvement, are observed in most patients.

4. Facial edema, which typically affects the entire face and parts of the lips, is present in 57%-100% of patients with acute oral Chagas disease. In those with acute symptoms from vector transmission, unilateral periorbital swelling (Romaña’s sign) is more common.

5. Other notable systemic symptoms include edema of the lower extremities, myalgia, generalized lymphadenopathy, abdominal discomfort, dyspnea, vomiting, diarrhea, hepatomegaly, splenomegaly, headache, chest pain, cutaneous erythematous rash, jaundice, arthralgia, epistaxis, hematemesis, melena, and palpitations.

6. The incubation period after oral ingestion of products contaminated with Trypanosoma cruzi is approximately 3-22 days, in contrast to 4-15 days for vector-borne transmission and 8-160 days for transfusion and transplant-related transmission.

7. Patients need antiparasitic drugs immediately.
 

Thinking Epidemiologically

Dr. Chuit recalled that suspicion of food contamination should be based on epidemiology, especially in outbreaks affecting several people and in regions where Chagas vectors have been described. Sometimes, however, a single careless tourist consumes contaminated products.

“The difficulty is that many times it is not considered, and if it is not considered, the search for the parasite is not requested,” said Dr. Chuit. He added that it is common for the professional to consider Chagas disease only if viral and bacterial isolation tests are negative. Clinicians sometimes consider Chagas disease because the patient has not responded to regular treatments for other causes, such as antibiotics and hydration.

Epidemiology is important, especially when Chagas disease is diagnosed in groups or a family, because they are usually not isolated cases but outbreaks of 3-40 cases, according to Dr. Chuit. “Under these conditions, it must be quickly considered…that this parasite may be involved.”

One of the difficulties is that the source of these oral transmissions is not recognized most of the time. In general, the sources are usually foods that are more likely to be contaminated by insects or insect feces, such as orange juice or sugarcane. But in fact, any food or beverage left unattended could be contaminated by vectors or possible secretions from infected marsupial odoriferous glands.

An analysis of 32 outbreaks from 1965 to 2022 showed that the main foods involved in oral transmission were homemade fruit juices. But different vector species were identified, and the reservoirs were mainly dogs, rodents, and large American opossums (Didelphis).

The largest oral Chagas outbreak was linked to the consumption of contaminated guava juice in a primary school in Caracas, Venezuela. Nonindustrially produced açaí is a common source of orally acquired Chagas disease in Brazil. In Colombia, Chagas disease has been associated with the consumption of palm wine, sugar cane, and tangerine juice. Other oral transmission routes include consuming meat from wild animals and ingesting blood from infected armadillos, which is related to a traditional medicine practice.
 

Deadly Yet Easily Treatable

In the outbreak of 119 confirmed and suspected cases in Venezuela, 20.3% required hospitalization, and a 5-year-old child died of acute myocarditis. These percentages differ from those reported in vector transmission, which is asymptomatic in the acute phase for 95%-99% of cases or will only develop a mild febrile illness that resolves on its own.

“Not all cases will present as severe, because depending on the inoculum, there may be individuals with subclinical situations. But any food poisoning that occurs in endemic areas, where food is not properly controlled, and these street foods are associated with processes in jungle areas, raises the possibility that T cruzi is involved and should be considered as a differential diagnosis,» noted Dr. Chuit. “The treatment is highly effective, and people recover quickly.”

“The most important thing about oral transmission of Chagas is that someone infected in this way needs antiparasitic drugs immediately. We can cure them if we treat them immediately,” said Dr. Beatty, adding that treatment is sometimes delayed due to lack of access to appropriate antiparasitic drugs. “Here in the United States and in Latin America, it is quite common for healthcare professionals not to understand the differences between vector, vertical, and oral transmission. By not treating these patients, they become ill quickly.”

Dr. Beatty and Dr. Chuit declared no relevant financial conflicts of interest.

This story was translated from the Medscape Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

The Ervebo vaccine not only reduces the risk for Ebola infection but also halves mortality rates. This is the result of a study published in The Lancet Infectious Diseases.

Rebecca Coulborn, an epidemiologist at Epicentre in Paris, France, and colleagues analyzed data collected during the 10th Ebola epidemic in the Democratic Republic of the Congo. Their analysis revealed that among the 2279 patients with confirmed Ebola who were admitted to an Ebola health facility between July 27, 2018, and April 27, 2020, the mortality risk was 56% for unvaccinated patients. In vaccinated patients, however, it was only 25%. The reduced mortality applied to all patients, regardless of age and gender.

The study was funded by Doctors Without Borders. For data collection, Epicentre, the epidemiological division of Doctors Without Borders, collaborated with the Institut National de Recherche Biomédicale and the Ministry of Health of the Democratic Republic of the Congo.

The study authors focused on the Ervebo vaccine, which is approved for use against Zaire ebolavirus in the European Union, the United States, and some African countries, among others. It is the only Ebola vaccine currently recommended for use during an epidemic. It is administered intramuscularly as a single dose and is approved for adults aged 18 years and older.

The vaccine is primarily recommended for ring vaccination of individuals at a high risk for infection during an epidemic. In studies, the vaccine has been used for ring vaccinations among contacts of diagnosed cases since the end of the Ebola outbreak in West Africa in 2014 and 2015 and since 2018 in the Democratic Republic of the Congo.

The preliminary estimated vaccine effectiveness 10 days after vaccination is 97.5%-100%. The duration of protection is unknown. Individuals who became ill despite vaccination typically experienced a milder course of illness.

Although people should be vaccinated as early as possible during Ebola outbreaks, the results of the Epicentre study showed that the vaccine still protects against the risk for infection even when administered after exposure to the virus.

Furthermore, Dr. Coulborn and her team found no antagonistic effect between vaccination and Ebola treatment in their analysis. “Vaccination following exposure to a person infected with Ebola still provides significant protection against death, even if administered shortly before the onset of symptoms,” said study author Dr. Coulborn in a press release from Doctors Without Borders.

This story was translated from the Medscape German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

The Ervebo vaccine not only reduces the risk for Ebola infection but also halves mortality rates. This is the result of a study published in The Lancet Infectious Diseases.

Rebecca Coulborn, an epidemiologist at Epicentre in Paris, France, and colleagues analyzed data collected during the 10th Ebola epidemic in the Democratic Republic of the Congo. Their analysis revealed that among the 2279 patients with confirmed Ebola who were admitted to an Ebola health facility between July 27, 2018, and April 27, 2020, the mortality risk was 56% for unvaccinated patients. In vaccinated patients, however, it was only 25%. The reduced mortality applied to all patients, regardless of age and gender.

The study was funded by Doctors Without Borders. For data collection, Epicentre, the epidemiological division of Doctors Without Borders, collaborated with the Institut National de Recherche Biomédicale and the Ministry of Health of the Democratic Republic of the Congo.

The study authors focused on the Ervebo vaccine, which is approved for use against Zaire ebolavirus in the European Union, the United States, and some African countries, among others. It is the only Ebola vaccine currently recommended for use during an epidemic. It is administered intramuscularly as a single dose and is approved for adults aged 18 years and older.

The vaccine is primarily recommended for ring vaccination of individuals at a high risk for infection during an epidemic. In studies, the vaccine has been used for ring vaccinations among contacts of diagnosed cases since the end of the Ebola outbreak in West Africa in 2014 and 2015 and since 2018 in the Democratic Republic of the Congo.

The preliminary estimated vaccine effectiveness 10 days after vaccination is 97.5%-100%. The duration of protection is unknown. Individuals who became ill despite vaccination typically experienced a milder course of illness.

Although people should be vaccinated as early as possible during Ebola outbreaks, the results of the Epicentre study showed that the vaccine still protects against the risk for infection even when administered after exposure to the virus.

Furthermore, Dr. Coulborn and her team found no antagonistic effect between vaccination and Ebola treatment in their analysis. “Vaccination following exposure to a person infected with Ebola still provides significant protection against death, even if administered shortly before the onset of symptoms,” said study author Dr. Coulborn in a press release from Doctors Without Borders.

This story was translated from the Medscape German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

The Ervebo vaccine not only reduces the risk for Ebola infection but also halves mortality rates. This is the result of a study published in The Lancet Infectious Diseases.

Rebecca Coulborn, an epidemiologist at Epicentre in Paris, France, and colleagues analyzed data collected during the 10th Ebola epidemic in the Democratic Republic of the Congo. Their analysis revealed that among the 2279 patients with confirmed Ebola who were admitted to an Ebola health facility between July 27, 2018, and April 27, 2020, the mortality risk was 56% for unvaccinated patients. In vaccinated patients, however, it was only 25%. The reduced mortality applied to all patients, regardless of age and gender.

The study was funded by Doctors Without Borders. For data collection, Epicentre, the epidemiological division of Doctors Without Borders, collaborated with the Institut National de Recherche Biomédicale and the Ministry of Health of the Democratic Republic of the Congo.

The study authors focused on the Ervebo vaccine, which is approved for use against Zaire ebolavirus in the European Union, the United States, and some African countries, among others. It is the only Ebola vaccine currently recommended for use during an epidemic. It is administered intramuscularly as a single dose and is approved for adults aged 18 years and older.

The vaccine is primarily recommended for ring vaccination of individuals at a high risk for infection during an epidemic. In studies, the vaccine has been used for ring vaccinations among contacts of diagnosed cases since the end of the Ebola outbreak in West Africa in 2014 and 2015 and since 2018 in the Democratic Republic of the Congo.

The preliminary estimated vaccine effectiveness 10 days after vaccination is 97.5%-100%. The duration of protection is unknown. Individuals who became ill despite vaccination typically experienced a milder course of illness.

Although people should be vaccinated as early as possible during Ebola outbreaks, the results of the Epicentre study showed that the vaccine still protects against the risk for infection even when administered after exposure to the virus.

Furthermore, Dr. Coulborn and her team found no antagonistic effect between vaccination and Ebola treatment in their analysis. “Vaccination following exposure to a person infected with Ebola still provides significant protection against death, even if administered shortly before the onset of symptoms,” said study author Dr. Coulborn in a press release from Doctors Without Borders.

This story was translated from the Medscape German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.