Management of neonatal herpes simplex virus infections

As many as 2,500 infants develop neonatal herpes each year, most of whom are born to women with no history or physical findings suggestive of genital herpes. Infection usually takes one of three forms: 1) disease localized to skin, eyes, and mucous membranes, 2) localized central nervous system infection, or 3) disseminated infection. Exposure to the virus occurs during passage through an infected birth canal, but 5% of infants acquire the infection in utero. The mortality rate is 31% for disseminated infection and 6% for localized central nervous system disease; long-term neurologic sequelae are seen in 17% and 70% of survivors, respectively. Diagnosis is made by isolating of the virus from skin lesions or other involved sites. The polymerase chain reaction for the detection of viral DNA in cerebrospinal fluid or serum is now the diagnostic test of choice for central nervous system or disseminated neonatal herpes because it has higher sensitivity than traditional culture methods. Treatment is with high-dose intravenous acyclovir (60 mg/kg per day in three divided doses), with adjustments made for infants with renal or hepatic insufficiency. Supportive measures and neuroimaging studies are often required. Acyclovir is administered for three weeks, but infants with disease localized to the skin, eyes, and mucous membranes can be treated for two weeks if the cerebrospinal fluid polymerase chain reaction assay is negative for herpes simplex virus DNA. Prevention of infection in infants can be accomplished by cesarean delivery when women have active lesions at the onset of labor. Neonates delivered through an infected birth canal should be screened between 24 and 48 hours of age with viral cultures of eyes, nasopharynx, mouth, and rectum. If positive, they should be treated with acyclovir even if asymptomatic. Suppressive acyclovir therapy beginning at 36 weeks gestation is often prescribed for women with frequent recurrences of genital herpes.