New Guidelines for Neonates Exposed to HSV During Delivery

Karyn Hede

January 28, 2013

Faster and more reliable serological and DNA tests for herpes simplex virus (HSV) now allow rapid testing of pregnant women to determine the risk for viral transmission to the infant during delivery. Because the risk for infection during delivery varies greatly depending on the type of maternal infection, the American Academy of Pediatrics (AAP) has developed a new management algorithm to guide evaluation of asymptomatic neonates. The new guidelines were published online January 28 in Pediatrics

About 1 in 4 adults in the United States carries HSV1 or HSV2, the viruses that cause genital herpes infections. Each year about 1500 cases of maternal–infant transmission of HSV are diagnosed in the United States, out of about 4 million live births.

Recent research has shown that the risk for transmission is much lower in mothers with recurrent lesions rather than a first-time infection. In a recent large study of almost 60,000 women in labor, 57% of infants delivered to women with a first-time HSV infection developed neonatal HSV disease compared with 2% of infants delivered to women with recurrent disease.

Commercially available serological tests can now distinguish type-specific HSV antibodies, making it possible to assess the relative risk for infection, and therefore potentially alter treatment strategies.

The AAP guidelines outline an approach to the management of neonates that assumes laboratory access to polymerase chain reaction (PCR) assays for HSV DNA or type-specific serological tests. The guidelines may not be applicable in clinical settings without rapid testing turnaround times. The AAP suggests obstetric providers and pediatricians work closely with diagnostic laboratories to ensure testing is available and turnaround times are acceptable.

Specific Recommendations

  • Women in labor with visible genital lesions should be swabbed for HSV PCR and culture. Any positive test result should be further analyzed to determine whether the virus is HSV-1 or HSV-2.

  • A history of genital herpes should be obtained preceding the pregnancy.

In cases of a recurrent maternal herpes outbreak, the following steps should be taken:

  • Skin and mucosal specimens should be obtained from the neonate for culture and PCR assay at approximately 24 hours after delivery, and blood should be sent for HSV DNA PCR assay. Preemptive treatment with the antiviral drug acyclovir need not be started as long as the infant remains asymptomatic.

  • If results become positive within 5 days, thus confirming neonatal HSV infection, the infant should undergo a complete evaluation to determine the extent of disease, and intravenous acyclovir should be initiated as soon as possible.

For women without a history of genital herpes, genital lesions at delivery could represent a first-time infection or recurrent infection, and the following steps should be taken:

  • Serological testing, which can determine which type of infection the outbreak represents, should be performed on maternal samples swabbed during delivery.

  • The infant should undergo a complete evaluation (lumbar puncture with cerebrospinal fluid sent for indices and HSV DNA PCR assay, in addition to serum alanine transaminase), and intravenous acyclovir should be initiated.

  • If the mother has a first-episode infection and the neonate's results are normal, the infant should be treated with intravenous acyclovir for 10 days.

  • If the neonate's results are positive, the infant should be treated for 14 to 21 days with intravenous acyclovir, depending on the extent of disease and reevaluated to ensure clearance of the virus.

  • After completion of acyclovir for treatment of neonatal HSV disease, infants should receive oral acyclovir suppressive therapy for 6 months.

This study was supported by the National Institute of Allergy and Infectious Diseases, National Institutes of Health, General Clinical Research Unit, and the State of Alabama. The authors have disclosed no other relevant financial relationships.

Pediatrics. Published online January 28, 2013. Full text