Herpes simplex virus.

Herpes simplex virus (HSV) infection is prevalent worldwide. Herpes labialis, caused predominantly by HSV-1, and herpes vulvovaginitis, caused predominantly by HSV-2, may result in significant morbidity and mortality for infected neonates exposed during delivery. The diagnosis of HSV infection is made by serological testing, viral culture, or polymerase chain reaction. Women with primary herpes vulvovaginitis exhibit a painful vesicular rash which is self-limited but may be followed by multiple recurrences. Women at greatest risk to transmit HSV to their neonates are those who experience their first episode of HSV during the latter stage of pregnancy. If infected, their neonates may have localized skin, eye and mucosal lesions, invasive central nervous system infection, or disseminated disease. Because of the potentially devastating outcome for a baby infected with HSV, pregnant women with active HSV lesions at delivery should be offered a cesarean section. Still, many neonates who are infected with HSV are born to women with asymptomatic HSV shedding. Therefore, prevention of HSV during pregnancy is exceedingly important.