Although infrequent, untreated
neonatal herpes results in death in half the cases and neurologic sequelae in three quarters of the survivors. Neonatal
infection is usually acquired from maternal
genital herpes, which is asymptomatic or unrecognized in 60% to 80% of women. The greatest risk of neonatal
infection occurs when the mother has primary
genital herpes involving the cervix at delivery, and the infant is premature and delivered with instrumentation (eg, scalp
electrodes). More than 80% of neonates with herpes will have typical herpetic lesions of the skin, eye, or mouth, and most of the remainder will have either
encephalitis or a
sepsis syndrome with
pneumonitis and
hepatitis and negative bacterial cultures. Because herpes can mimic other neonatal
infections, laboratory diagnosis is important, using cultures of the virus from lesions, peripheral blood white cells, or CSF. Treatment with intravenous
acyclovir does reduce mortality and neurologic sequelae, but outcome is still guarded in babies with disseminated disease or
encephalitis. Prevention focuses on
caesarean section in women with active lesions at the time of impending delivery and avoidance of postnatal exposure. Further studies are needed to determine whether maternal screening (eg, HSV-2 type specific
antibodies and vaginal cultures in selected women at delivery) will be cost effective in preventing
neonatal herpes.