Primary HSV infections in pregnant women can result in more severe diseases than that in non-pregnant ones. This mechanism is known as asymptomatic virus shedding 2,11. As a result, most genital herpes infections are transmitted by persons unaware that they have the infection or who are asymptomatic when transmission occurs. Prevention of neonatal herpes depends both on preventing acquisition of genital HSV infection during late pregnancy and avoiding exposure of the neonate to herpetic lesions and viral shedding during delivery. Primary gingivostomatitis results in viral shedding in oral secretions for an average of seven to 10 days. Virus can be isolated from the saliva of asymptomatic children as well. HSV-1 genital infections can result from either genital-genital contact or oral-genital contact with an infected person who is actively shedding virus. Herpes simplex virus disease of the newborn is acquired in one of three distinct times: intrauterine (in utero), peripartum (perinatal), and postpartum (postnatal).
The risk of transmitting HSV to an infant during delivery is determined in part by the mother’s previous immunity to HSV. Infants born to mothers who have a first episode of genital HSV infection near term and are shedding virus at delivery are at much greater risk of developing neonatal herpes than are infants whose mothers have recurrent genital herpes (Fig 1). Infants whose PCR assay result remains positive should continue to receive intravenous antiviral therapy until the CSF PCR assay result is negative. Neonatal infection is usually the result of HSV 2 as this is the main virus associated with genital infection. There is a 1 chance of women with a history of genital HSV infection shedding virus at the time of delivery. If untreated, 70 will progress to disseminated disease. It may result in small blisters in groups often called cold sores or fever blisters or may just cause a sore throat. HSV-1 more commonly causes oral infections while HSV-2 more commonly causes genital infections. Antivirals may reduce asymptomatic shedding; asymptomatic genital HSV-2 viral shedding is believed to occur on 20 of days per year in patients not undergoing antiviral treatment, versus 10 of days while on antiviral therapy.
Genital herpes simplex virus (HSV) infection during pregnancy poses a significant risk to the developing fetus and newborn. The risk of maternal transmission of this virus to the fetus or newborn is a major health concern. These episodes usually are thought to be the result of an initial HSV-2 infection in the presence of partially protective HSV-1 antibodies. Asymptomatic genital shedding of herpes from a subclinical primary genital infection may be associated with preterm delivery. Viral shedding often is asymptomatic, but it also can result in a recognized recurrent infection in which symptoms and visible skin lesions develop. The high incidence of relatively asymptomatic primary HSV-2 in pregnancy may be explained in part by the high prevalence of HSV-1 antibody, particularly among women in lower socioeconomic groups. Most sexual partners, however, do not report having had a typical episode of clinically recognizable HSV around the time of viral transmission. Transmission to the newborn may result in serious complications including but not limited to seizures, blindness, and death. One third of these develop cold sores and one half are asymptomatic. However, up to 70 of neonatal herpes is acquired through mothers who shed asymptomatically near or during labor.
Guidance On Management Of Asymptomatic Neonates Born To Women With Active Genital Herpes Lesions