Infectious Diseases Society for Obstetrics and Gynecology (IDSOG): Annual Scientific Meeting

ANNAPOLIS, MD. – Three novel treatments for gonorrhea, currently in late stages of development, could give clinicians an edge in the fight against antibacterial resistance, according to a federal health official.

The pathogen Neisseria gonorrhoeae is already showing signs of besting first-line therapy ceftriaxone in Japan and parts of Europe, said Carolyn Deal, PhD, chief of the sexually transmitted diseases branch at the National Institute of Allergy and Infectious Diseases (NIAID). And the Centers for Disease Control and Prevention lists N. gonorrhoeae among its “urgent” antibiotic resistance threats.

“I think we have a new superbug,” Dr. Deal said at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology. “In my opinion, it’s just a matter of time in this country.”

But three agents in late-stage clinical trials for uncomplicated urogenital gonorrhea offer promise in fighting the gram-negative bacteria, according to Dr. Deal. The first is solithromycin, manufactured by Cempra. The company has a phase III study underway to compare a single dose of oral solithromycin with intramuscular ceftriaxone plus oral azithromycin for urogenital gonorrhea.

The other two drugs are first-in-class antibacterial agents. In partnership with the NIAID, the company Entasis recently completed a phase II study of zoliflodacin, an oral agent in a novel class of topoisomerase inhibitors. A phase III trial is expected to begin in 2017, also in partnership with the NIAID, according to an Entasis document. The third agent is gepotidacin, a novel triazaacenaphthylene antibacterial agent currently being investigated by GlaxoSmithKline in a phase II study.

Centers for Disease Control and Prevention

Because N. gonorrhoeae poses such an urgent threat, waiting to develop a vaccine is less feasible than working with companies to develop additional antibacterial agents, Dr. Deal said. But taking a compound out of the basic research lab and having enough data to get into the investigational new drug phase is a significant investment, she said, so pharmaceutical manufacturers look for as many indications for a drug as possible.

For instance, solithromycin was initially investigated for community-acquired pneumonia. Gepotidacin initially was developed in partnership with the NIAID and the Biomedical Advanced Research and Development Authority in case of an anthrax attack, Dr. Deal said. “The Entasis product is the only one specifically developed for Neisseria gonorrhoeae,” she said.

One reason that two of the drugs in the pipeline include N. gonorrhoeae as an indication is that the Food and Drug Administration has issued guidance on developing drugs in the area of uncomplicated gonorrhea. That guidance is lacking for nasopharyngeal and rectal gonorrhea, leaving a “vacuum” in the pipeline, Dr. Deal said. “Many of us have come to the conclusion that developing vaccines is the only real long-term solution.”

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Three novel treatments for gonorrhea, currently in late stages of development, could give clinicians an edge in the fight against antibacterial resistance, according to a federal health official.

The pathogen Neisseria gonorrhoeae is already showing signs of besting first-line therapy ceftriaxone in Japan and parts of Europe, said Carolyn Deal, PhD, chief of the sexually transmitted diseases branch at the National Institute of Allergy and Infectious Diseases (NIAID). And the Centers for Disease Control and Prevention lists N. gonorrhoeae among its “urgent” antibiotic resistance threats.

“I think we have a new superbug,” Dr. Deal said at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology. “In my opinion, it’s just a matter of time in this country.”

But three agents in late-stage clinical trials for uncomplicated urogenital gonorrhea offer promise in fighting the gram-negative bacteria, according to Dr. Deal. The first is solithromycin, manufactured by Cempra. The company has a phase III study underway to compare a single dose of oral solithromycin with intramuscular ceftriaxone plus oral azithromycin for urogenital gonorrhea.

The other two drugs are first-in-class antibacterial agents. In partnership with the NIAID, the company Entasis recently completed a phase II study of zoliflodacin, an oral agent in a novel class of topoisomerase inhibitors. A phase III trial is expected to begin in 2017, also in partnership with the NIAID, according to an Entasis document. The third agent is gepotidacin, a novel triazaacenaphthylene antibacterial agent currently being investigated by GlaxoSmithKline in a phase II study.

Centers for Disease Control and Prevention

Because N. gonorrhoeae poses such an urgent threat, waiting to develop a vaccine is less feasible than working with companies to develop additional antibacterial agents, Dr. Deal said. But taking a compound out of the basic research lab and having enough data to get into the investigational new drug phase is a significant investment, she said, so pharmaceutical manufacturers look for as many indications for a drug as possible.

For instance, solithromycin was initially investigated for community-acquired pneumonia. Gepotidacin initially was developed in partnership with the NIAID and the Biomedical Advanced Research and Development Authority in case of an anthrax attack, Dr. Deal said. “The Entasis product is the only one specifically developed for Neisseria gonorrhoeae,” she said.

One reason that two of the drugs in the pipeline include N. gonorrhoeae as an indication is that the Food and Drug Administration has issued guidance on developing drugs in the area of uncomplicated gonorrhea. That guidance is lacking for nasopharyngeal and rectal gonorrhea, leaving a “vacuum” in the pipeline, Dr. Deal said. “Many of us have come to the conclusion that developing vaccines is the only real long-term solution.”

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Three novel treatments for gonorrhea, currently in late stages of development, could give clinicians an edge in the fight against antibacterial resistance, according to a federal health official.

The pathogen Neisseria gonorrhoeae is already showing signs of besting first-line therapy ceftriaxone in Japan and parts of Europe, said Carolyn Deal, PhD, chief of the sexually transmitted diseases branch at the National Institute of Allergy and Infectious Diseases (NIAID). And the Centers for Disease Control and Prevention lists N. gonorrhoeae among its “urgent” antibiotic resistance threats.

“I think we have a new superbug,” Dr. Deal said at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology. “In my opinion, it’s just a matter of time in this country.”

But three agents in late-stage clinical trials for uncomplicated urogenital gonorrhea offer promise in fighting the gram-negative bacteria, according to Dr. Deal. The first is solithromycin, manufactured by Cempra. The company has a phase III study underway to compare a single dose of oral solithromycin with intramuscular ceftriaxone plus oral azithromycin for urogenital gonorrhea.

The other two drugs are first-in-class antibacterial agents. In partnership with the NIAID, the company Entasis recently completed a phase II study of zoliflodacin, an oral agent in a novel class of topoisomerase inhibitors. A phase III trial is expected to begin in 2017, also in partnership with the NIAID, according to an Entasis document. The third agent is gepotidacin, a novel triazaacenaphthylene antibacterial agent currently being investigated by GlaxoSmithKline in a phase II study.

Centers for Disease Control and Prevention

Because N. gonorrhoeae poses such an urgent threat, waiting to develop a vaccine is less feasible than working with companies to develop additional antibacterial agents, Dr. Deal said. But taking a compound out of the basic research lab and having enough data to get into the investigational new drug phase is a significant investment, she said, so pharmaceutical manufacturers look for as many indications for a drug as possible.

For instance, solithromycin was initially investigated for community-acquired pneumonia. Gepotidacin initially was developed in partnership with the NIAID and the Biomedical Advanced Research and Development Authority in case of an anthrax attack, Dr. Deal said. “The Entasis product is the only one specifically developed for Neisseria gonorrhoeae,” she said.

One reason that two of the drugs in the pipeline include N. gonorrhoeae as an indication is that the Food and Drug Administration has issued guidance on developing drugs in the area of uncomplicated gonorrhea. That guidance is lacking for nasopharyngeal and rectal gonorrhea, leaving a “vacuum” in the pipeline, Dr. Deal said. “Many of us have come to the conclusion that developing vaccines is the only real long-term solution.”

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Women with bacterial vaginosis could soon have an effective oral, single-dose treatment option, if results of a phase III study result in approval by the Food and Drug Administration.

In a modified intention-to-treat study of 189 women with bacterial vaginosis (BV) randomly assigned 2:1 to treatment or placebo, a single, granulated oral dose of secnidazole 2g was found to be statistically superior to placebo on all clinical endpoints.

Secnidazole (SYM-1219) has a longer half-life, compared with metronidazole, the current treatment standard, according to Jane R. Schwebke, MD, the study investigator and a professor of medicine in the infectious disease department of the University of Alabama, Birmingham. Dr. Schwebke credits the study drug’s high bioavailablility and rapid absorption for its efficacy.

“You get a very high peak with SYM-1219 initially, and I think that might be the reason for the single-dose therapy’s efficacy. It’s due to the pharmacokinetics of the drug itself,” she reported at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology.

If the drug is approved, it would likely mean better adherence when compared with current standards of treatment, according to Sharon Hillier, PhD, director of reproductive infectious disease research at the Magee-Women’s Hospital of the University of Pittsburgh.

“It will absolutely improve compliance,” Dr. Hillier said in an interview. “Obviously, it’s much easier than taking [metronidazole] twice a day for 7 days.”

Treatment with metronidazole also requires a week of abstinence from alcohol, compared with what Dr. Hillier anticipates would be 2 or 3 days of alcohol abstinence with secnidazole.

The initial study enrollment was 189 women who were randomized 2:1 to secnidazole or placebo and treated at 21 sites nationally. After assessment for common sexually transmitted diseases, Nugent scores of 4 or greater, and all Amsel criteria (including a vaginal pH of 4.7 or greater, clue cells at or greater than 20%, and a positive KOH whiff test), 164 women remained in the modified intention-to-treat (ITT) analysis. A quarter of all women across the modified ITT group were recurrent BV sufferers, having had at least four episodes of BV in the previous year, and 87% had Nugent scores of 7 or greater.

“These were true BV cases; none were in the intermediate or mild zone,” Dr. Schwebke said.

Responders were women who, between days 21 and 30, had “normal” discharge, less than 20% clue cells, and a negative KOH whiff test. In the study arm, 53.3% of women had “normal” discharge and less than 20% clue cells at their 21-30 day visit, compared with 19.3% in the placebo group (P less than .001). The secondary endpoint – Nugent scores of 3 or less at days 7-14 – was achieved by 43.9% in the study group, compared with 5.3% of controls (P less than .001).

Just over a third of women in the study arm experienced one or more adverse events, compared with 21.9% of controls. Yeast infections were the most common adverse event. Less than 5% of the study group experienced nausea, headache, or diarrhea, compared with up to 3% of controls.

“What’s exciting about this new product is that it will be a single dose oral [that women] can take with a meal and with none of the adverse effects, and it relieves symptoms as well as other treatments,” Dr. Hillier said.

How treatment efficacy should be defined was a matter of debate during the presentation’s question and answer period. The FDA did not issue BV treatment guidance until 1998, despite prior approval of BV treatments clindamycin and metronidazole. The rigorous definition of clinical cure rate put forward in the FDA guidance document caused the cure rates that had been generally accepted by physicians to drop from as high as 80% to around 40%, according to Dr. Hilliard.

“I personally would like to see some head-to-head comparisons of the various treatments we have to know whether some are better than others,” Dr. Hillier said in the interview.

The ideal BV treatment should also provoke a microbiological cure, according to Dr. Schwebke. “What I would do is combine a drug like this with a biofilm inhibitor. Right now, this is great, because it’s single dose oral, and it’s as good as anything out there, but, I don’t think we’re taking the next step necessarily with efficacy.”

The study was supported by Symbiomix. Dr. Schwebke is a consultant for Symbiomix and receives funding from Alfa Wassermann and Starpharma, among others. Dr. Hillier is coprincipal investigator of the Microbicide Trials Network, sponsored by the National Institutes of Health.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Women with bacterial vaginosis could soon have an effective oral, single-dose treatment option, if results of a phase III study result in approval by the Food and Drug Administration.

In a modified intention-to-treat study of 189 women with bacterial vaginosis (BV) randomly assigned 2:1 to treatment or placebo, a single, granulated oral dose of secnidazole 2g was found to be statistically superior to placebo on all clinical endpoints.

Secnidazole (SYM-1219) has a longer half-life, compared with metronidazole, the current treatment standard, according to Jane R. Schwebke, MD, the study investigator and a professor of medicine in the infectious disease department of the University of Alabama, Birmingham. Dr. Schwebke credits the study drug’s high bioavailablility and rapid absorption for its efficacy.

“You get a very high peak with SYM-1219 initially, and I think that might be the reason for the single-dose therapy’s efficacy. It’s due to the pharmacokinetics of the drug itself,” she reported at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology.

If the drug is approved, it would likely mean better adherence when compared with current standards of treatment, according to Sharon Hillier, PhD, director of reproductive infectious disease research at the Magee-Women’s Hospital of the University of Pittsburgh.

“It will absolutely improve compliance,” Dr. Hillier said in an interview. “Obviously, it’s much easier than taking [metronidazole] twice a day for 7 days.”

Treatment with metronidazole also requires a week of abstinence from alcohol, compared with what Dr. Hillier anticipates would be 2 or 3 days of alcohol abstinence with secnidazole.

The initial study enrollment was 189 women who were randomized 2:1 to secnidazole or placebo and treated at 21 sites nationally. After assessment for common sexually transmitted diseases, Nugent scores of 4 or greater, and all Amsel criteria (including a vaginal pH of 4.7 or greater, clue cells at or greater than 20%, and a positive KOH whiff test), 164 women remained in the modified intention-to-treat (ITT) analysis. A quarter of all women across the modified ITT group were recurrent BV sufferers, having had at least four episodes of BV in the previous year, and 87% had Nugent scores of 7 or greater.

“These were true BV cases; none were in the intermediate or mild zone,” Dr. Schwebke said.

Responders were women who, between days 21 and 30, had “normal” discharge, less than 20% clue cells, and a negative KOH whiff test. In the study arm, 53.3% of women had “normal” discharge and less than 20% clue cells at their 21-30 day visit, compared with 19.3% in the placebo group (P less than .001). The secondary endpoint – Nugent scores of 3 or less at days 7-14 – was achieved by 43.9% in the study group, compared with 5.3% of controls (P less than .001).

Just over a third of women in the study arm experienced one or more adverse events, compared with 21.9% of controls. Yeast infections were the most common adverse event. Less than 5% of the study group experienced nausea, headache, or diarrhea, compared with up to 3% of controls.

“What’s exciting about this new product is that it will be a single dose oral [that women] can take with a meal and with none of the adverse effects, and it relieves symptoms as well as other treatments,” Dr. Hillier said.

How treatment efficacy should be defined was a matter of debate during the presentation’s question and answer period. The FDA did not issue BV treatment guidance until 1998, despite prior approval of BV treatments clindamycin and metronidazole. The rigorous definition of clinical cure rate put forward in the FDA guidance document caused the cure rates that had been generally accepted by physicians to drop from as high as 80% to around 40%, according to Dr. Hilliard.

“I personally would like to see some head-to-head comparisons of the various treatments we have to know whether some are better than others,” Dr. Hillier said in the interview.

The ideal BV treatment should also provoke a microbiological cure, according to Dr. Schwebke. “What I would do is combine a drug like this with a biofilm inhibitor. Right now, this is great, because it’s single dose oral, and it’s as good as anything out there, but, I don’t think we’re taking the next step necessarily with efficacy.”

The study was supported by Symbiomix. Dr. Schwebke is a consultant for Symbiomix and receives funding from Alfa Wassermann and Starpharma, among others. Dr. Hillier is coprincipal investigator of the Microbicide Trials Network, sponsored by the National Institutes of Health.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Women with bacterial vaginosis could soon have an effective oral, single-dose treatment option, if results of a phase III study result in approval by the Food and Drug Administration.

In a modified intention-to-treat study of 189 women with bacterial vaginosis (BV) randomly assigned 2:1 to treatment or placebo, a single, granulated oral dose of secnidazole 2g was found to be statistically superior to placebo on all clinical endpoints.

Secnidazole (SYM-1219) has a longer half-life, compared with metronidazole, the current treatment standard, according to Jane R. Schwebke, MD, the study investigator and a professor of medicine in the infectious disease department of the University of Alabama, Birmingham. Dr. Schwebke credits the study drug’s high bioavailablility and rapid absorption for its efficacy.

“You get a very high peak with SYM-1219 initially, and I think that might be the reason for the single-dose therapy’s efficacy. It’s due to the pharmacokinetics of the drug itself,” she reported at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology.

If the drug is approved, it would likely mean better adherence when compared with current standards of treatment, according to Sharon Hillier, PhD, director of reproductive infectious disease research at the Magee-Women’s Hospital of the University of Pittsburgh.

“It will absolutely improve compliance,” Dr. Hillier said in an interview. “Obviously, it’s much easier than taking [metronidazole] twice a day for 7 days.”

Treatment with metronidazole also requires a week of abstinence from alcohol, compared with what Dr. Hillier anticipates would be 2 or 3 days of alcohol abstinence with secnidazole.

The initial study enrollment was 189 women who were randomized 2:1 to secnidazole or placebo and treated at 21 sites nationally. After assessment for common sexually transmitted diseases, Nugent scores of 4 or greater, and all Amsel criteria (including a vaginal pH of 4.7 or greater, clue cells at or greater than 20%, and a positive KOH whiff test), 164 women remained in the modified intention-to-treat (ITT) analysis. A quarter of all women across the modified ITT group were recurrent BV sufferers, having had at least four episodes of BV in the previous year, and 87% had Nugent scores of 7 or greater.

“These were true BV cases; none were in the intermediate or mild zone,” Dr. Schwebke said.

Responders were women who, between days 21 and 30, had “normal” discharge, less than 20% clue cells, and a negative KOH whiff test. In the study arm, 53.3% of women had “normal” discharge and less than 20% clue cells at their 21-30 day visit, compared with 19.3% in the placebo group (P less than .001). The secondary endpoint – Nugent scores of 3 or less at days 7-14 – was achieved by 43.9% in the study group, compared with 5.3% of controls (P less than .001).

Just over a third of women in the study arm experienced one or more adverse events, compared with 21.9% of controls. Yeast infections were the most common adverse event. Less than 5% of the study group experienced nausea, headache, or diarrhea, compared with up to 3% of controls.

“What’s exciting about this new product is that it will be a single dose oral [that women] can take with a meal and with none of the adverse effects, and it relieves symptoms as well as other treatments,” Dr. Hillier said.

How treatment efficacy should be defined was a matter of debate during the presentation’s question and answer period. The FDA did not issue BV treatment guidance until 1998, despite prior approval of BV treatments clindamycin and metronidazole. The rigorous definition of clinical cure rate put forward in the FDA guidance document caused the cure rates that had been generally accepted by physicians to drop from as high as 80% to around 40%, according to Dr. Hilliard.

“I personally would like to see some head-to-head comparisons of the various treatments we have to know whether some are better than others,” Dr. Hillier said in the interview.

The ideal BV treatment should also provoke a microbiological cure, according to Dr. Schwebke. “What I would do is combine a drug like this with a biofilm inhibitor. Right now, this is great, because it’s single dose oral, and it’s as good as anything out there, but, I don’t think we’re taking the next step necessarily with efficacy.”

The study was supported by Symbiomix. Dr. Schwebke is a consultant for Symbiomix and receives funding from Alfa Wassermann and Starpharma, among others. Dr. Hillier is coprincipal investigator of the Microbicide Trials Network, sponsored by the National Institutes of Health.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Febrile infections occurring in the second trimester appear to pose the greatest risk to the neurodevelopment of the fetus, a population based cohort study has shown.

In a review of 8,618,171 California births between January 1991 and December 2008, Ms. Hilary Haber, a third-year medical student at the University of California, Davis, and her coinvestigators found that maternal infections requiring hospitalizations during the second trimester were associated with a relative risk of 2.5 of having a child with epilepsy, a relative risk of 2.3 of having a child with an intellectual disability, and a relative risk of 1.2 of having a child with autism.

Significant associations were observed between subcategories of infection and intellectual disability and epilepsy, particularly those of a bacterial cause and from respiratory and genitourinary sites. Overall, any maternal infection during pregnancy was associated with a 43% increased risk of epilepsy, a 33% increased risk of intellectual disability, and an 8% increased risk of autism.

The exact mechanism of action between the maternal infection and adverse fetal neurodevelopmental outcomes is still unclear, Ms. Haber said at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology.

“Next, we are considering which specific [maternal] infections we should look at,” Ms. Haber said in an interview. “There is something about febrile infections, so we want to narrow that down and better characterize the outcomes from mild, moderate, severe infections.”

Ms. Haber reported having no relevant financial disclosures.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Febrile infections occurring in the second trimester appear to pose the greatest risk to the neurodevelopment of the fetus, a population based cohort study has shown.

In a review of 8,618,171 California births between January 1991 and December 2008, Ms. Hilary Haber, a third-year medical student at the University of California, Davis, and her coinvestigators found that maternal infections requiring hospitalizations during the second trimester were associated with a relative risk of 2.5 of having a child with epilepsy, a relative risk of 2.3 of having a child with an intellectual disability, and a relative risk of 1.2 of having a child with autism.

Significant associations were observed between subcategories of infection and intellectual disability and epilepsy, particularly those of a bacterial cause and from respiratory and genitourinary sites. Overall, any maternal infection during pregnancy was associated with a 43% increased risk of epilepsy, a 33% increased risk of intellectual disability, and an 8% increased risk of autism.

The exact mechanism of action between the maternal infection and adverse fetal neurodevelopmental outcomes is still unclear, Ms. Haber said at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology.

“Next, we are considering which specific [maternal] infections we should look at,” Ms. Haber said in an interview. “There is something about febrile infections, so we want to narrow that down and better characterize the outcomes from mild, moderate, severe infections.”

Ms. Haber reported having no relevant financial disclosures.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – Febrile infections occurring in the second trimester appear to pose the greatest risk to the neurodevelopment of the fetus, a population based cohort study has shown.

In a review of 8,618,171 California births between January 1991 and December 2008, Ms. Hilary Haber, a third-year medical student at the University of California, Davis, and her coinvestigators found that maternal infections requiring hospitalizations during the second trimester were associated with a relative risk of 2.5 of having a child with epilepsy, a relative risk of 2.3 of having a child with an intellectual disability, and a relative risk of 1.2 of having a child with autism.

Significant associations were observed between subcategories of infection and intellectual disability and epilepsy, particularly those of a bacterial cause and from respiratory and genitourinary sites. Overall, any maternal infection during pregnancy was associated with a 43% increased risk of epilepsy, a 33% increased risk of intellectual disability, and an 8% increased risk of autism.

The exact mechanism of action between the maternal infection and adverse fetal neurodevelopmental outcomes is still unclear, Ms. Haber said at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology.

“Next, we are considering which specific [maternal] infections we should look at,” Ms. Haber said in an interview. “There is something about febrile infections, so we want to narrow that down and better characterize the outcomes from mild, moderate, severe infections.”

Ms. Haber reported having no relevant financial disclosures.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – The definition of taking a thorough travel history has expanded with the spread of Zika.

Physicians “need to focus not only on patients’ travel histories, but also the travel histories and future travel plans of our patients’ sexual partners,” Ilona T. Goldfarb, a perinatologist at Massachusetts General Hospital, Boston, said in an interview. “We cannot rely on our patients to just [offer] that they’ve been in the Caribbean. We have to ask them diligently, and at every visit.”

Dr. Goldfarb added that immigration is a risk for Zika exposure, and may be a barrier to accurate history taking. In these cases, travel history will need to be performed in the patient’s spoken language to ensure accuracy, Dr. Goldfarb said. To track and communicate Zika information, Dr. Goldfarb and her colleagues have developed a three-part response based on their experience with previous infectious disease emergencies:

1. Communication. The practice is in regular communication with the Centers for Disease Control and Prevention and the state public health department to ensure they are up to date on all guidelines.

2. Education. Dr. Goldfarb and her practice colleagues routinely brief each other and patients on any new information, including recommended testing and guidelines, as well as travel warnings.

3. Tracking. Clinicians use a tracking worksheet for every patient screened for potential Zika exposure, allowing them to prospectively and retrospectively review patients. This has already proven useful, Dr. Goldfarb said, when the CDC changed its guidance around testing of asymptomatic patients.

In a presentation at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology, Dr. Goldfarb presented the data that she and her colleagues have collected so far on patients with Zika exposure.

As of Aug. 10, 2016, the practice had screened 142 women for Zika virus exposure since January 2016. More than 80% of the exposure came from travel to Zika-endemic areas. There have been few cases of exposure reported through sex, but Dr. Goldfarb said she thinks this type of exposure has been underreported because the link between infection and sex was not known until more recently.

Of the patients screened, 87% were appropriate candidates for Zika virus serum testing under CDC guidelines. There have been four positive serum tests for Zika exposure in Dr. Goldfarb’s patients so far.

In the one live birth, the newborn showed no visible signs of abnormalities. Testing revealed Zika virus RNA in the placenta, but not in the cord blood. The other three pregnancies were either terminated or associated with miscarriages. Again, Zika was detected in the placentas, but not in the fetuses.

Testing protocols have been a moving target since the outbreak began, according to Dr. Goldfarb. Some patients who call or are screened for possible exposure “are not actually eligible for testing because of the time frame or location of travel.”

To make sure that appropriate testing is being performed, Dr. Goldfarb advised designating an in-practice “Zika expert.” In her own practice, Dr. Goldfarb and one other colleague handle all Zika screening and inquiries from patients and colleagues. “This has greatly improved our efficiency and the experience for the patients,” she said in an interview.

The Massachusetts Department of Public Health is piloting a program with Dr. Goldfarb’s practice to determine if using the “designated expert” approach will improve laboratory wait times, compared with the standard protocol of having clinicians obtain approval from a state epidemiologist before sending patient serum samples for testing.

It has taken from 2 to 68 days to receive test results from the state lab, although a period of 17 days is typical, Dr. Goldfarb reported. The process has improved since last March when state health officials ramped up their capacity, she said.

As of Aug. 10, Dr. Goldfarb’s practice has performed 107 ultrasounds for patients with suspected Zika virus, averaging 3 per patient. Across all ultrasounds, there were three abnormalities, including one case of bilateral ventriculomegaly. Earlier in that pregnancy, the patient had tested negative for Zika on real-time reverse transcription polymerase chain reaction testing, which simultaneously screens for dengue, chikungunya, and Zika. Serum testing was also negative for Zika in the two other pregnancies with fetal abnormalities.

Dr. Goldfarb said she couldn’t quantify how much time is being spent on Zika screening and counseling since that is not being tracked, but she estimated that her practice takes between three and five calls or questions per day regarding the virus.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – The definition of taking a thorough travel history has expanded with the spread of Zika.

Physicians “need to focus not only on patients’ travel histories, but also the travel histories and future travel plans of our patients’ sexual partners,” Ilona T. Goldfarb, a perinatologist at Massachusetts General Hospital, Boston, said in an interview. “We cannot rely on our patients to just [offer] that they’ve been in the Caribbean. We have to ask them diligently, and at every visit.”

Dr. Goldfarb added that immigration is a risk for Zika exposure, and may be a barrier to accurate history taking. In these cases, travel history will need to be performed in the patient’s spoken language to ensure accuracy, Dr. Goldfarb said. To track and communicate Zika information, Dr. Goldfarb and her colleagues have developed a three-part response based on their experience with previous infectious disease emergencies:

1. Communication. The practice is in regular communication with the Centers for Disease Control and Prevention and the state public health department to ensure they are up to date on all guidelines.

2. Education. Dr. Goldfarb and her practice colleagues routinely brief each other and patients on any new information, including recommended testing and guidelines, as well as travel warnings.

3. Tracking. Clinicians use a tracking worksheet for every patient screened for potential Zika exposure, allowing them to prospectively and retrospectively review patients. This has already proven useful, Dr. Goldfarb said, when the CDC changed its guidance around testing of asymptomatic patients.

In a presentation at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology, Dr. Goldfarb presented the data that she and her colleagues have collected so far on patients with Zika exposure.

As of Aug. 10, 2016, the practice had screened 142 women for Zika virus exposure since January 2016. More than 80% of the exposure came from travel to Zika-endemic areas. There have been few cases of exposure reported through sex, but Dr. Goldfarb said she thinks this type of exposure has been underreported because the link between infection and sex was not known until more recently.

Of the patients screened, 87% were appropriate candidates for Zika virus serum testing under CDC guidelines. There have been four positive serum tests for Zika exposure in Dr. Goldfarb’s patients so far.

In the one live birth, the newborn showed no visible signs of abnormalities. Testing revealed Zika virus RNA in the placenta, but not in the cord blood. The other three pregnancies were either terminated or associated with miscarriages. Again, Zika was detected in the placentas, but not in the fetuses.

Testing protocols have been a moving target since the outbreak began, according to Dr. Goldfarb. Some patients who call or are screened for possible exposure “are not actually eligible for testing because of the time frame or location of travel.”

To make sure that appropriate testing is being performed, Dr. Goldfarb advised designating an in-practice “Zika expert.” In her own practice, Dr. Goldfarb and one other colleague handle all Zika screening and inquiries from patients and colleagues. “This has greatly improved our efficiency and the experience for the patients,” she said in an interview.

The Massachusetts Department of Public Health is piloting a program with Dr. Goldfarb’s practice to determine if using the “designated expert” approach will improve laboratory wait times, compared with the standard protocol of having clinicians obtain approval from a state epidemiologist before sending patient serum samples for testing.

It has taken from 2 to 68 days to receive test results from the state lab, although a period of 17 days is typical, Dr. Goldfarb reported. The process has improved since last March when state health officials ramped up their capacity, she said.

As of Aug. 10, Dr. Goldfarb’s practice has performed 107 ultrasounds for patients with suspected Zika virus, averaging 3 per patient. Across all ultrasounds, there were three abnormalities, including one case of bilateral ventriculomegaly. Earlier in that pregnancy, the patient had tested negative for Zika on real-time reverse transcription polymerase chain reaction testing, which simultaneously screens for dengue, chikungunya, and Zika. Serum testing was also negative for Zika in the two other pregnancies with fetal abnormalities.

Dr. Goldfarb said she couldn’t quantify how much time is being spent on Zika screening and counseling since that is not being tracked, but she estimated that her practice takes between three and five calls or questions per day regarding the virus.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – The definition of taking a thorough travel history has expanded with the spread of Zika.

Physicians “need to focus not only on patients’ travel histories, but also the travel histories and future travel plans of our patients’ sexual partners,” Ilona T. Goldfarb, a perinatologist at Massachusetts General Hospital, Boston, said in an interview. “We cannot rely on our patients to just [offer] that they’ve been in the Caribbean. We have to ask them diligently, and at every visit.”

Dr. Goldfarb added that immigration is a risk for Zika exposure, and may be a barrier to accurate history taking. In these cases, travel history will need to be performed in the patient’s spoken language to ensure accuracy, Dr. Goldfarb said. To track and communicate Zika information, Dr. Goldfarb and her colleagues have developed a three-part response based on their experience with previous infectious disease emergencies:

1. Communication. The practice is in regular communication with the Centers for Disease Control and Prevention and the state public health department to ensure they are up to date on all guidelines.

2. Education. Dr. Goldfarb and her practice colleagues routinely brief each other and patients on any new information, including recommended testing and guidelines, as well as travel warnings.

3. Tracking. Clinicians use a tracking worksheet for every patient screened for potential Zika exposure, allowing them to prospectively and retrospectively review patients. This has already proven useful, Dr. Goldfarb said, when the CDC changed its guidance around testing of asymptomatic patients.

In a presentation at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology, Dr. Goldfarb presented the data that she and her colleagues have collected so far on patients with Zika exposure.

As of Aug. 10, 2016, the practice had screened 142 women for Zika virus exposure since January 2016. More than 80% of the exposure came from travel to Zika-endemic areas. There have been few cases of exposure reported through sex, but Dr. Goldfarb said she thinks this type of exposure has been underreported because the link between infection and sex was not known until more recently.

Of the patients screened, 87% were appropriate candidates for Zika virus serum testing under CDC guidelines. There have been four positive serum tests for Zika exposure in Dr. Goldfarb’s patients so far.

In the one live birth, the newborn showed no visible signs of abnormalities. Testing revealed Zika virus RNA in the placenta, but not in the cord blood. The other three pregnancies were either terminated or associated with miscarriages. Again, Zika was detected in the placentas, but not in the fetuses.

Testing protocols have been a moving target since the outbreak began, according to Dr. Goldfarb. Some patients who call or are screened for possible exposure “are not actually eligible for testing because of the time frame or location of travel.”

To make sure that appropriate testing is being performed, Dr. Goldfarb advised designating an in-practice “Zika expert.” In her own practice, Dr. Goldfarb and one other colleague handle all Zika screening and inquiries from patients and colleagues. “This has greatly improved our efficiency and the experience for the patients,” she said in an interview.

The Massachusetts Department of Public Health is piloting a program with Dr. Goldfarb’s practice to determine if using the “designated expert” approach will improve laboratory wait times, compared with the standard protocol of having clinicians obtain approval from a state epidemiologist before sending patient serum samples for testing.

It has taken from 2 to 68 days to receive test results from the state lab, although a period of 17 days is typical, Dr. Goldfarb reported. The process has improved since last March when state health officials ramped up their capacity, she said.

As of Aug. 10, Dr. Goldfarb’s practice has performed 107 ultrasounds for patients with suspected Zika virus, averaging 3 per patient. Across all ultrasounds, there were three abnormalities, including one case of bilateral ventriculomegaly. Earlier in that pregnancy, the patient had tested negative for Zika on real-time reverse transcription polymerase chain reaction testing, which simultaneously screens for dengue, chikungunya, and Zika. Serum testing was also negative for Zika in the two other pregnancies with fetal abnormalities.

Dr. Goldfarb said she couldn’t quantify how much time is being spent on Zika screening and counseling since that is not being tracked, but she estimated that her practice takes between three and five calls or questions per day regarding the virus.

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – The scramble to learn exactly how and when after infection the Zika virus affects the developing fetus has put pregnant women at the center of an unprecedented infectious disease emergency response.

“It’s the most complicated infectious disease response we’ve ever done,” Dana Meaney-Delman, MD, of the Centers for Disease Control and Prevention, told an audience at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology. “It’s also the first time an emergency response team has included an ob.gyn.”

Although research into Zika virus is happening at breakneck speed, every finding seems to lead to still more questions. “It’s hard to keep up,” said Dr. Meaney-Delman, who is a Clinical Deputy on the Pregnancy and Birth Defects Task Force, part of the CDC’s Zika virus response.

What is known

What is known is that Zika virus is primarily vector-borne, either manifesting as a mild illness or remaining subclinical. The virus is also communicable through male-to-female sex, female-to-female sex, blood donation, and organ transplantation. Once infected, one is immune; if symptomatic, the presentation clears within a couple of weeks. If a woman is infected during pregnancy, it can be transmitted to the developing fetus, including at the time of birth, according to Dr. Meaney-Delman.

©Whitney McKnight

“We know transmission can occur in any trimester. We’ve seen it in the placenta, in amniotic fluid, in the brain, as well as in the brains of infants who have died,” she said.

Whether the virus poses a risk to the fetus around the time of conception is not clear, but Dr. Meaney-Delman said that since other infections such as rubella and cytomegalovirus do pose a risk, the CDC is issuing Zika guidance accordingly.

Despite an initial theory that pregnant women were more susceptible to Zika infection, there is no evidence to date confirming this, but “the combination of mosquitoes and sexual transmission really puts a woman of reproductive age at risk,” said Catherine Y. Spong, MD, who also spoke during the meeting. Dr. Spong is acting director of the National Institute of Child Health and Human Development, part of the National Institutes of Health.

Based on data derived from other flaviviruses, the “good news” is that infected nonpregnant women who later want to conceive do not have a higher risk of bearing a child with Zika-related complications, according to Dr. Meaney-Delman.

Abnormalities seen and unseen

During the initial stages of the Zika outbreak in Brazil, the spiking rate of babies born with microcephaly attracted the most attention; yet it is now apparent that children were also born with a growing list of other Zika-associated pregnancy outcomes that likely were missed at the time, according to Dr. Spong.

“That’s not to say that a child that doesn’t have microcephaly does or doesn’t have some of these other complications. We don’t know; they weren’t studied because they didn’t have the microcephaly,” Dr Spong said. “To get the data right, you need to follow all the children.”

Brain abnormalities such as ventriculomegaly and intracranial calcifications, as well as a range of growth abnormalities, miscarriage, and stillbirth are increasingly associated with infants born to infected women. Data is also beginning to link Zika virus to limb abnormalities, hypertonia, hearing loss, damage to the eyes and central nervous system, and seizures.

The World Health Organization has also noted the involvement of the cardiac, genitourinary, and digestive systems in babies born to infected mothers in Panama and Colombia. “The caveat [to these data], is that all these women were symptomatic,” Dr. Spong said, noting that in Brazil, where the outbreak was first documented, 80% of the infected pregnant women were asymptomatic during the pregnancy.

“Just because the mother has no symptoms, she’s fine? That doesn’t make any sense to me,” Dr. Spong said. “We know that infections in pregnancy can result in long-term outcomes in kids that you don’t have the ability to diagnose at birth. We need to be cognizant of this and we need to study it.”

Although initial theories were that viremia in symptomatic women was likely higher, thus imparting a higher risk of infection in their fetus, Dr. Meaney-Delman said the number of asymptomatic women whose fetuses are affected has debunked this line of thinking.

Risk of infection during pregnancy

As to what the actual risk of Zika virus infection is during pregnancy, “honestly we don’t know,” said Dr. Spong. “There are modeling estimates that [it’s] between 1% and 13% in a first trimester infection, but we don’t have the hard and fast data.”

The Zika in Infants and Pregnancy (ZIP) study, recently launched by the NIH, will provide a prospective look at birth outcomes in 10,000 women aged 15 years and older who will be followed throughout their pregnancies to determine if they become infected with Zika virus, and if so, how infection impacts birth outcomes.

The international, multi-site study will help clarify the timing of risk, Dr. Spong said, and is intended to elucidate pregnancy risks in symptomatic vs. asymptomatic women. The study will also help indicate whether nutritional, socioeconomic status, and other cofactors such as Dengue infection are implicated. Once born, all children in the study will be observed for a year. “Even if they have no abnormalities, after birth there could be developmental delays, or more subtle consequences later on in the child’s life,” Dr. Meaney-Delman said.

Meanwhile, researchers are attempting to map how varying levels of viremia affect transmission. Zika virus has been found in semen after 90 days in at least two studies, “and we don’t know if Zika can be transmitted through other bodily fluids,” Dr. Spong said.

Surveillance data from the CDC’s Zika Pregnancy Registry has shown viremia in symptomatic women can last up to 46 days after onset of symptoms. In at least one asymptomatic pregnant woman, viremia was detected 53 days after exposure. Another study found prolonged viremia – 10 weeks – in a patient who had Zika infection in her first trimester; imaging showed the fetus was developing normally until week 20, when signs of severe brain abnormalities were detected.

The emerging picture of Zika’s potential for prolonged viremia has prompted the CDC to recommend clinicians use reverse transcription–polymerase chain reaction (RT-PCR) testing rather than serologic testing, as it is more sensitive and helps rule out other flavivirus infections, which require different management, Dr. Meaney-Delman said.

Potential mechanisms of action

“It’s clear that the virus does directly infect human cortical neural progenitor cells with very high efficiency, and in doing so, stunts their growth, dysregulates transcription, and causes cell death,” Dr. Spong said.

Researchers have also found that Zika replicates in subgroups of trophoblasts and endothelial cells, and in primary human placental macrophages, resulting in vascular damage and growth restriction. Other research suggests the virus spreads from basal and parietal decidua to chorionic villi and amniochorionic membranes, leading to the theory that uterine-placental suppression of the viral entry cofactor TIM1 could stop transmission to the fetus.

Prevention and management

CDC officials expect the current outbreak to mimic past flavivirus outbreaks which were contained locally in portions of the South and U.S. territories, Dr. Meaney-Delman said. Still, she emphasized that clinicians should screen patients, regardless of location. “Each pregnant women should be assessed for [vector] exposure, travel, and sexual exposure and asked about symptoms consistent with Zika virus,” Dr. Meaney-Delman said.

She also emphasized the importance of patients consistently using insect repellent and using condoms during pregnancy, as Zika has been detected in semen for as long as 6 months. “It’s been very hard to invoke this behavioral change in women, but it’s very effective.”

The CDC continues to update guidance, including how to evaluate newborns for Zika-related defects.

As for what resources might be needed in future to help affected families, in an interview Dr. Meaney-Delman said that depends on information still unknown. “Zika is a public health concern that we should be factoring in long term, but what we do about it will depend upon the outcomes,” she said. “If there are children that are born normal but who have lab evidence of Zika, then we will probably not do much. I don’t think we have a projection yet.”

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – The scramble to learn exactly how and when after infection the Zika virus affects the developing fetus has put pregnant women at the center of an unprecedented infectious disease emergency response.

“It’s the most complicated infectious disease response we’ve ever done,” Dana Meaney-Delman, MD, of the Centers for Disease Control and Prevention, told an audience at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology. “It’s also the first time an emergency response team has included an ob.gyn.”

Although research into Zika virus is happening at breakneck speed, every finding seems to lead to still more questions. “It’s hard to keep up,” said Dr. Meaney-Delman, who is a Clinical Deputy on the Pregnancy and Birth Defects Task Force, part of the CDC’s Zika virus response.

What is known

What is known is that Zika virus is primarily vector-borne, either manifesting as a mild illness or remaining subclinical. The virus is also communicable through male-to-female sex, female-to-female sex, blood donation, and organ transplantation. Once infected, one is immune; if symptomatic, the presentation clears within a couple of weeks. If a woman is infected during pregnancy, it can be transmitted to the developing fetus, including at the time of birth, according to Dr. Meaney-Delman.

©Whitney McKnight

“We know transmission can occur in any trimester. We’ve seen it in the placenta, in amniotic fluid, in the brain, as well as in the brains of infants who have died,” she said.

Whether the virus poses a risk to the fetus around the time of conception is not clear, but Dr. Meaney-Delman said that since other infections such as rubella and cytomegalovirus do pose a risk, the CDC is issuing Zika guidance accordingly.

Despite an initial theory that pregnant women were more susceptible to Zika infection, there is no evidence to date confirming this, but “the combination of mosquitoes and sexual transmission really puts a woman of reproductive age at risk,” said Catherine Y. Spong, MD, who also spoke during the meeting. Dr. Spong is acting director of the National Institute of Child Health and Human Development, part of the National Institutes of Health.

Based on data derived from other flaviviruses, the “good news” is that infected nonpregnant women who later want to conceive do not have a higher risk of bearing a child with Zika-related complications, according to Dr. Meaney-Delman.

Abnormalities seen and unseen

During the initial stages of the Zika outbreak in Brazil, the spiking rate of babies born with microcephaly attracted the most attention; yet it is now apparent that children were also born with a growing list of other Zika-associated pregnancy outcomes that likely were missed at the time, according to Dr. Spong.

“That’s not to say that a child that doesn’t have microcephaly does or doesn’t have some of these other complications. We don’t know; they weren’t studied because they didn’t have the microcephaly,” Dr Spong said. “To get the data right, you need to follow all the children.”

Brain abnormalities such as ventriculomegaly and intracranial calcifications, as well as a range of growth abnormalities, miscarriage, and stillbirth are increasingly associated with infants born to infected women. Data is also beginning to link Zika virus to limb abnormalities, hypertonia, hearing loss, damage to the eyes and central nervous system, and seizures.

The World Health Organization has also noted the involvement of the cardiac, genitourinary, and digestive systems in babies born to infected mothers in Panama and Colombia. “The caveat [to these data], is that all these women were symptomatic,” Dr. Spong said, noting that in Brazil, where the outbreak was first documented, 80% of the infected pregnant women were asymptomatic during the pregnancy.

“Just because the mother has no symptoms, she’s fine? That doesn’t make any sense to me,” Dr. Spong said. “We know that infections in pregnancy can result in long-term outcomes in kids that you don’t have the ability to diagnose at birth. We need to be cognizant of this and we need to study it.”

Although initial theories were that viremia in symptomatic women was likely higher, thus imparting a higher risk of infection in their fetus, Dr. Meaney-Delman said the number of asymptomatic women whose fetuses are affected has debunked this line of thinking.

Risk of infection during pregnancy

As to what the actual risk of Zika virus infection is during pregnancy, “honestly we don’t know,” said Dr. Spong. “There are modeling estimates that [it’s] between 1% and 13% in a first trimester infection, but we don’t have the hard and fast data.”

The Zika in Infants and Pregnancy (ZIP) study, recently launched by the NIH, will provide a prospective look at birth outcomes in 10,000 women aged 15 years and older who will be followed throughout their pregnancies to determine if they become infected with Zika virus, and if so, how infection impacts birth outcomes.

The international, multi-site study will help clarify the timing of risk, Dr. Spong said, and is intended to elucidate pregnancy risks in symptomatic vs. asymptomatic women. The study will also help indicate whether nutritional, socioeconomic status, and other cofactors such as Dengue infection are implicated. Once born, all children in the study will be observed for a year. “Even if they have no abnormalities, after birth there could be developmental delays, or more subtle consequences later on in the child’s life,” Dr. Meaney-Delman said.

Meanwhile, researchers are attempting to map how varying levels of viremia affect transmission. Zika virus has been found in semen after 90 days in at least two studies, “and we don’t know if Zika can be transmitted through other bodily fluids,” Dr. Spong said.

Surveillance data from the CDC’s Zika Pregnancy Registry has shown viremia in symptomatic women can last up to 46 days after onset of symptoms. In at least one asymptomatic pregnant woman, viremia was detected 53 days after exposure. Another study found prolonged viremia – 10 weeks – in a patient who had Zika infection in her first trimester; imaging showed the fetus was developing normally until week 20, when signs of severe brain abnormalities were detected.

The emerging picture of Zika’s potential for prolonged viremia has prompted the CDC to recommend clinicians use reverse transcription–polymerase chain reaction (RT-PCR) testing rather than serologic testing, as it is more sensitive and helps rule out other flavivirus infections, which require different management, Dr. Meaney-Delman said.

Potential mechanisms of action

“It’s clear that the virus does directly infect human cortical neural progenitor cells with very high efficiency, and in doing so, stunts their growth, dysregulates transcription, and causes cell death,” Dr. Spong said.

Researchers have also found that Zika replicates in subgroups of trophoblasts and endothelial cells, and in primary human placental macrophages, resulting in vascular damage and growth restriction. Other research suggests the virus spreads from basal and parietal decidua to chorionic villi and amniochorionic membranes, leading to the theory that uterine-placental suppression of the viral entry cofactor TIM1 could stop transmission to the fetus.

Prevention and management

CDC officials expect the current outbreak to mimic past flavivirus outbreaks which were contained locally in portions of the South and U.S. territories, Dr. Meaney-Delman said. Still, she emphasized that clinicians should screen patients, regardless of location. “Each pregnant women should be assessed for [vector] exposure, travel, and sexual exposure and asked about symptoms consistent with Zika virus,” Dr. Meaney-Delman said.

She also emphasized the importance of patients consistently using insect repellent and using condoms during pregnancy, as Zika has been detected in semen for as long as 6 months. “It’s been very hard to invoke this behavioral change in women, but it’s very effective.”

The CDC continues to update guidance, including how to evaluate newborns for Zika-related defects.

As for what resources might be needed in future to help affected families, in an interview Dr. Meaney-Delman said that depends on information still unknown. “Zika is a public health concern that we should be factoring in long term, but what we do about it will depend upon the outcomes,” she said. “If there are children that are born normal but who have lab evidence of Zika, then we will probably not do much. I don’t think we have a projection yet.”

[email protected]

On Twitter @whitneymcknight

ANNAPOLIS, MD. – The scramble to learn exactly how and when after infection the Zika virus affects the developing fetus has put pregnant women at the center of an unprecedented infectious disease emergency response.

“It’s the most complicated infectious disease response we’ve ever done,” Dana Meaney-Delman, MD, of the Centers for Disease Control and Prevention, told an audience at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology. “It’s also the first time an emergency response team has included an ob.gyn.”

Although research into Zika virus is happening at breakneck speed, every finding seems to lead to still more questions. “It’s hard to keep up,” said Dr. Meaney-Delman, who is a Clinical Deputy on the Pregnancy and Birth Defects Task Force, part of the CDC’s Zika virus response.

What is known

What is known is that Zika virus is primarily vector-borne, either manifesting as a mild illness or remaining subclinical. The virus is also communicable through male-to-female sex, female-to-female sex, blood donation, and organ transplantation. Once infected, one is immune; if symptomatic, the presentation clears within a couple of weeks. If a woman is infected during pregnancy, it can be transmitted to the developing fetus, including at the time of birth, according to Dr. Meaney-Delman.

©Whitney McKnight

“We know transmission can occur in any trimester. We’ve seen it in the placenta, in amniotic fluid, in the brain, as well as in the brains of infants who have died,” she said.

Whether the virus poses a risk to the fetus around the time of conception is not clear, but Dr. Meaney-Delman said that since other infections such as rubella and cytomegalovirus do pose a risk, the CDC is issuing Zika guidance accordingly.

Despite an initial theory that pregnant women were more susceptible to Zika infection, there is no evidence to date confirming this, but “the combination of mosquitoes and sexual transmission really puts a woman of reproductive age at risk,” said Catherine Y. Spong, MD, who also spoke during the meeting. Dr. Spong is acting director of the National Institute of Child Health and Human Development, part of the National Institutes of Health.

Based on data derived from other flaviviruses, the “good news” is that infected nonpregnant women who later want to conceive do not have a higher risk of bearing a child with Zika-related complications, according to Dr. Meaney-Delman.

Abnormalities seen and unseen

During the initial stages of the Zika outbreak in Brazil, the spiking rate of babies born with microcephaly attracted the most attention; yet it is now apparent that children were also born with a growing list of other Zika-associated pregnancy outcomes that likely were missed at the time, according to Dr. Spong.

“That’s not to say that a child that doesn’t have microcephaly does or doesn’t have some of these other complications. We don’t know; they weren’t studied because they didn’t have the microcephaly,” Dr Spong said. “To get the data right, you need to follow all the children.”

Brain abnormalities such as ventriculomegaly and intracranial calcifications, as well as a range of growth abnormalities, miscarriage, and stillbirth are increasingly associated with infants born to infected women. Data is also beginning to link Zika virus to limb abnormalities, hypertonia, hearing loss, damage to the eyes and central nervous system, and seizures.

The World Health Organization has also noted the involvement of the cardiac, genitourinary, and digestive systems in babies born to infected mothers in Panama and Colombia. “The caveat [to these data], is that all these women were symptomatic,” Dr. Spong said, noting that in Brazil, where the outbreak was first documented, 80% of the infected pregnant women were asymptomatic during the pregnancy.

“Just because the mother has no symptoms, she’s fine? That doesn’t make any sense to me,” Dr. Spong said. “We know that infections in pregnancy can result in long-term outcomes in kids that you don’t have the ability to diagnose at birth. We need to be cognizant of this and we need to study it.”

Although initial theories were that viremia in symptomatic women was likely higher, thus imparting a higher risk of infection in their fetus, Dr. Meaney-Delman said the number of asymptomatic women whose fetuses are affected has debunked this line of thinking.

Risk of infection during pregnancy

As to what the actual risk of Zika virus infection is during pregnancy, “honestly we don’t know,” said Dr. Spong. “There are modeling estimates that [it’s] between 1% and 13% in a first trimester infection, but we don’t have the hard and fast data.”

The Zika in Infants and Pregnancy (ZIP) study, recently launched by the NIH, will provide a prospective look at birth outcomes in 10,000 women aged 15 years and older who will be followed throughout their pregnancies to determine if they become infected with Zika virus, and if so, how infection impacts birth outcomes.

The international, multi-site study will help clarify the timing of risk, Dr. Spong said, and is intended to elucidate pregnancy risks in symptomatic vs. asymptomatic women. The study will also help indicate whether nutritional, socioeconomic status, and other cofactors such as Dengue infection are implicated. Once born, all children in the study will be observed for a year. “Even if they have no abnormalities, after birth there could be developmental delays, or more subtle consequences later on in the child’s life,” Dr. Meaney-Delman said.

Meanwhile, researchers are attempting to map how varying levels of viremia affect transmission. Zika virus has been found in semen after 90 days in at least two studies, “and we don’t know if Zika can be transmitted through other bodily fluids,” Dr. Spong said.

Surveillance data from the CDC’s Zika Pregnancy Registry has shown viremia in symptomatic women can last up to 46 days after onset of symptoms. In at least one asymptomatic pregnant woman, viremia was detected 53 days after exposure. Another study found prolonged viremia – 10 weeks – in a patient who had Zika infection in her first trimester; imaging showed the fetus was developing normally until week 20, when signs of severe brain abnormalities were detected.

The emerging picture of Zika’s potential for prolonged viremia has prompted the CDC to recommend clinicians use reverse transcription–polymerase chain reaction (RT-PCR) testing rather than serologic testing, as it is more sensitive and helps rule out other flavivirus infections, which require different management, Dr. Meaney-Delman said.

Potential mechanisms of action

“It’s clear that the virus does directly infect human cortical neural progenitor cells with very high efficiency, and in doing so, stunts their growth, dysregulates transcription, and causes cell death,” Dr. Spong said.

Researchers have also found that Zika replicates in subgroups of trophoblasts and endothelial cells, and in primary human placental macrophages, resulting in vascular damage and growth restriction. Other research suggests the virus spreads from basal and parietal decidua to chorionic villi and amniochorionic membranes, leading to the theory that uterine-placental suppression of the viral entry cofactor TIM1 could stop transmission to the fetus.

Prevention and management

CDC officials expect the current outbreak to mimic past flavivirus outbreaks which were contained locally in portions of the South and U.S. territories, Dr. Meaney-Delman said. Still, she emphasized that clinicians should screen patients, regardless of location. “Each pregnant women should be assessed for [vector] exposure, travel, and sexual exposure and asked about symptoms consistent with Zika virus,” Dr. Meaney-Delman said.

She also emphasized the importance of patients consistently using insect repellent and using condoms during pregnancy, as Zika has been detected in semen for as long as 6 months. “It’s been very hard to invoke this behavioral change in women, but it’s very effective.”

The CDC continues to update guidance, including how to evaluate newborns for Zika-related defects.

As for what resources might be needed in future to help affected families, in an interview Dr. Meaney-Delman said that depends on information still unknown. “Zika is a public health concern that we should be factoring in long term, but what we do about it will depend upon the outcomes,” she said. “If there are children that are born normal but who have lab evidence of Zika, then we will probably not do much. I don’t think we have a projection yet.”

[email protected]

On Twitter @whitneymcknight