Neonatal Herpes: The 24th-Hour Workup

Christopher J. Chiu, MD: Hello. We are The Cribsiders. On our pediatric medicine podcast, we interview leading experts in the field to bring you clinical pearls, practice-changing knowledge, and answers to lingering questions about core topics in pediatric medicine. Today we're going to talk about neonatal herpes simplex virus (HSV).

Justin L. Berk, MD, MPH, MBA: We talked about neonatal HSV with Dr Christopher Golden, neonatologist and associate professor of pediatrics at Johns Hopkins University School of Medicine.

Chiu: Neonates who are exposed to HSV in the first 30 days of life are at very high risk of developing infection. But the scariest thing about this is that they can present up to 6 weeks of age. How do they get infected? We learned that 85% of these infections arise from exposure during delivery. Only 10% arise from postnatal exposure, like being kissed or touched by someone with a cold sore or herpetic whitlow.

Berk: It was a big teaching point for me that the majority of these exposures are not from women who have recurrent infections. In fact, the increased likelihood of vertical transmission occurs with mothers who have active primary infections. If the mother has active lesions anywhere, regardless of whether it's primary or recurrent, that can still clearly cause vertical transmission.