Summer Enteroviruses: Avoid Antibiotics

During the summer and early fall, we should be careful about unnecessary antibiotic use in patients who most likely have enteroviral infections.

Nonpolio enterovirus (NPEV) infections are amazingly diverse in their range of clinical manifestations. While most of these infections are self-limited and nonserious, NPEV can turn serious and even fatal in newborns and immunosuppressed individuals. Of course, the diagnosis is easy when we see a child with the classic hand-foot-and-mouth (HFM) blister presentation. But that happens in only a small proportion of cases.

More commonly, we see a child with a high fever, sore throat, a slightly stiff neck, and a very worried mother. Even with a negative strep test, sometimes we retreat to our comfort zone and prescribe amoxicillin. While understandable, we should try to avoid this practice.

In a study my colleagues and I conducted a few years ago, only 8% of 372 children with a clinical diagnosis of systemic NPEV syndrome presented with HFM blisters. More common were stomatitis in 58%, and fever with myalgias and malaise in 28%. Another 3% had pleurodynia, 3% had fever with rash, and 1% had aseptic meningitis. Most patients had four to seven symptoms at the onset of illness and at the time of presentation (Pediatrics 1998;102:1126–34).

To my knowledge, there have been no other published studies since that one on the epidemiology of enteroviral illness in private clinical practice.

Of the 372 index cases, more than half (53%) also had a family member with an NPEV illness, including 51% of the 105 with myalgia/malaise, 20% of the 10 with rash, 57% of the 214 with stomatitis, and 45% of the 11 with pleurodynia. Interestingly, the illness often presented differently in different family members. It was not uncommon, for example, to see one child with HFM, another with just rash and fever, and the mother with malaise and myalgia, but with the identical virus isolated from all three. We were somewhat surprised by this finding.

Also unexpected was the long duration of illness in many instances. While we typically think of a “summer cold” as lasting no more than 2–3 days, in our study the myalgias and malaise lasted a mean of 9.5 days, stomatitis lasted 7 days, HFM 7.2 days, rash 6 days, pleurodynia 8.8 days, and meningitis 6.5 days. Unless we caution our patients about how long these symptoms can linger, we're sure to see them back in our offices, asking for antibiotics.

Unfortunately, efforts that began a decade or so ago to develop rapid-test enterovirus kits for widespread clinical use fell by the wayside for a variety of reasons. Some tertiary medical centers do have polymerase chain reaction-based rapid tests, but their cost is prohibitive for most community hospitals and private physicians' offices.

What I've found most useful in my practice is a simple white blood cell count. Most of these children will have a drop in their WBC count consistent with a viral infection, and an increase in their lymphocytes (“right shift”). During the summer or early fall, a febrile illness—even a high febrile illness—with no specific signs to indicate bacterial disease is most likely caused by an enterovirus.

That knowledge—coupled with a low WBC count and a right shift—should be sufficient in 90% of cases to ensure that you don't need empiric antibiotic therapy, as long as you have good follow-up with the patient.

The exceptions to that are newborns less than 2 months of age and immunosuppressed patients of any age. In those cases, a sepsis work-up is still advised. Indeed, a recent review paper noted that severe NPEV disease develops in a subset of newborns infected in the first 2 weeks of life, consisting of sepsis, meningoencephalitis, myocarditis, pneumonia, hepatitis, and/or coagulopathy. Substantial mortality has been reported, and long-term sequelae may occur among survivors (Paediatr. Drugs 2004;6:1–10).

The National Institute of Allergy and Infectious Diseases had funded an investigation of pleconaril—an agent that inhibits viral attachment to host cell receptors—for use in infants with enteroviral sepsis.

The study was suspended earlier this year, but NIAID is currently in talks with manufacturer Schering-Plough Corp. to restart the trial.

During the summer and early fall, we should be careful about unnecessary antibiotic use in patients who most likely have enteroviral infections.

Nonpolio enterovirus (NPEV) infections are amazingly diverse in their range of clinical manifestations. While most of these infections are self-limited and nonserious, NPEV can turn serious and even fatal in newborns and immunosuppressed individuals. Of course, the diagnosis is easy when we see a child with the classic hand-foot-and-mouth (HFM) blister presentation. But that happens in only a small proportion of cases.

More commonly, we see a child with a high fever, sore throat, a slightly stiff neck, and a very worried mother. Even with a negative strep test, sometimes we retreat to our comfort zone and prescribe amoxicillin. While understandable, we should try to avoid this practice.

In a study my colleagues and I conducted a few years ago, only 8% of 372 children with a clinical diagnosis of systemic NPEV syndrome presented with HFM blisters. More common were stomatitis in 58%, and fever with myalgias and malaise in 28%. Another 3% had pleurodynia, 3% had fever with rash, and 1% had aseptic meningitis. Most patients had four to seven symptoms at the onset of illness and at the time of presentation (Pediatrics 1998;102:1126–34).

To my knowledge, there have been no other published studies since that one on the epidemiology of enteroviral illness in private clinical practice.

Of the 372 index cases, more than half (53%) also had a family member with an NPEV illness, including 51% of the 105 with myalgia/malaise, 20% of the 10 with rash, 57% of the 214 with stomatitis, and 45% of the 11 with pleurodynia. Interestingly, the illness often presented differently in different family members. It was not uncommon, for example, to see one child with HFM, another with just rash and fever, and the mother with malaise and myalgia, but with the identical virus isolated from all three. We were somewhat surprised by this finding.

Also unexpected was the long duration of illness in many instances. While we typically think of a “summer cold” as lasting no more than 2–3 days, in our study the myalgias and malaise lasted a mean of 9.5 days, stomatitis lasted 7 days, HFM 7.2 days, rash 6 days, pleurodynia 8.8 days, and meningitis 6.5 days. Unless we caution our patients about how long these symptoms can linger, we're sure to see them back in our offices, asking for antibiotics.

Unfortunately, efforts that began a decade or so ago to develop rapid-test enterovirus kits for widespread clinical use fell by the wayside for a variety of reasons. Some tertiary medical centers do have polymerase chain reaction-based rapid tests, but their cost is prohibitive for most community hospitals and private physicians' offices.

What I've found most useful in my practice is a simple white blood cell count. Most of these children will have a drop in their WBC count consistent with a viral infection, and an increase in their lymphocytes (“right shift”). During the summer or early fall, a febrile illness—even a high febrile illness—with no specific signs to indicate bacterial disease is most likely caused by an enterovirus.

That knowledge—coupled with a low WBC count and a right shift—should be sufficient in 90% of cases to ensure that you don't need empiric antibiotic therapy, as long as you have good follow-up with the patient.

The exceptions to that are newborns less than 2 months of age and immunosuppressed patients of any age. In those cases, a sepsis work-up is still advised. Indeed, a recent review paper noted that severe NPEV disease develops in a subset of newborns infected in the first 2 weeks of life, consisting of sepsis, meningoencephalitis, myocarditis, pneumonia, hepatitis, and/or coagulopathy. Substantial mortality has been reported, and long-term sequelae may occur among survivors (Paediatr. Drugs 2004;6:1–10).

The National Institute of Allergy and Infectious Diseases had funded an investigation of pleconaril—an agent that inhibits viral attachment to host cell receptors—for use in infants with enteroviral sepsis.

The study was suspended earlier this year, but NIAID is currently in talks with manufacturer Schering-Plough Corp. to restart the trial.

During the summer and early fall, we should be careful about unnecessary antibiotic use in patients who most likely have enteroviral infections.

Nonpolio enterovirus (NPEV) infections are amazingly diverse in their range of clinical manifestations. While most of these infections are self-limited and nonserious, NPEV can turn serious and even fatal in newborns and immunosuppressed individuals. Of course, the diagnosis is easy when we see a child with the classic hand-foot-and-mouth (HFM) blister presentation. But that happens in only a small proportion of cases.

More commonly, we see a child with a high fever, sore throat, a slightly stiff neck, and a very worried mother. Even with a negative strep test, sometimes we retreat to our comfort zone and prescribe amoxicillin. While understandable, we should try to avoid this practice.

In a study my colleagues and I conducted a few years ago, only 8% of 372 children with a clinical diagnosis of systemic NPEV syndrome presented with HFM blisters. More common were stomatitis in 58%, and fever with myalgias and malaise in 28%. Another 3% had pleurodynia, 3% had fever with rash, and 1% had aseptic meningitis. Most patients had four to seven symptoms at the onset of illness and at the time of presentation (Pediatrics 1998;102:1126–34).

To my knowledge, there have been no other published studies since that one on the epidemiology of enteroviral illness in private clinical practice.

Of the 372 index cases, more than half (53%) also had a family member with an NPEV illness, including 51% of the 105 with myalgia/malaise, 20% of the 10 with rash, 57% of the 214 with stomatitis, and 45% of the 11 with pleurodynia. Interestingly, the illness often presented differently in different family members. It was not uncommon, for example, to see one child with HFM, another with just rash and fever, and the mother with malaise and myalgia, but with the identical virus isolated from all three. We were somewhat surprised by this finding.

Also unexpected was the long duration of illness in many instances. While we typically think of a “summer cold” as lasting no more than 2–3 days, in our study the myalgias and malaise lasted a mean of 9.5 days, stomatitis lasted 7 days, HFM 7.2 days, rash 6 days, pleurodynia 8.8 days, and meningitis 6.5 days. Unless we caution our patients about how long these symptoms can linger, we're sure to see them back in our offices, asking for antibiotics.

Unfortunately, efforts that began a decade or so ago to develop rapid-test enterovirus kits for widespread clinical use fell by the wayside for a variety of reasons. Some tertiary medical centers do have polymerase chain reaction-based rapid tests, but their cost is prohibitive for most community hospitals and private physicians' offices.

What I've found most useful in my practice is a simple white blood cell count. Most of these children will have a drop in their WBC count consistent with a viral infection, and an increase in their lymphocytes (“right shift”). During the summer or early fall, a febrile illness—even a high febrile illness—with no specific signs to indicate bacterial disease is most likely caused by an enterovirus.

That knowledge—coupled with a low WBC count and a right shift—should be sufficient in 90% of cases to ensure that you don't need empiric antibiotic therapy, as long as you have good follow-up with the patient.

The exceptions to that are newborns less than 2 months of age and immunosuppressed patients of any age. In those cases, a sepsis work-up is still advised. Indeed, a recent review paper noted that severe NPEV disease develops in a subset of newborns infected in the first 2 weeks of life, consisting of sepsis, meningoencephalitis, myocarditis, pneumonia, hepatitis, and/or coagulopathy. Substantial mortality has been reported, and long-term sequelae may occur among survivors (Paediatr. Drugs 2004;6:1–10).

The National Institute of Allergy and Infectious Diseases had funded an investigation of pleconaril—an agent that inhibits viral attachment to host cell receptors—for use in infants with enteroviral sepsis.

The study was suspended earlier this year, but NIAID is currently in talks with manufacturer Schering-Plough Corp. to restart the trial.