Herpes simplex virus: Prevalence in placental tissue and incidence in neonatal cord blood samples

Abstract

Herpes simplex virus (HSV) infection is one ofthe most prevalent infectious diseases world-wide, with HSV -2 being primarily associatedwith genital infections. HSV-2 is believed toaccount for the majority of cases of neonatalherpes, which may cause diverse of complica-tions in infected newborns. T he present studysought to estimate the prevalence of HSV-2 inplacental tissue samples and the incidence ofHSV-2 in the umbilical cord blood of newborninfants. Placental tissue sample s from 201women (maternal-side and fetal-side ¼ 402specimens) and 184 neonatal cord blood sam-ples, all collected at the obstetric ward of aUniversity hospital were studied. HSV-2 wasdetected by means of nested PCR. The preva-lence of HSV-2 in placental samples was 9.0%(n ¼ 18), and the incidence of neonatal HSV-2infection was 1.1% (n ¼ 2). All HSV-2-positivepatients were asymptomatic at the time ofdelivery and none reported genital herpes.Women with a time between rupture of mem-branes and delivery of 360 min had an ap-proximately fourfold risk of HSV-2 infection inthe placental tissue (95% CI 0.93–5.66,P ¼ 0.01). These results suggest that HSV-2 ispresent in the placenta of asymptomatic wom-en and that a risk of transmission to theneonate exists. New strategies must be imple-mented for the management of asy mptomaticpatients who are capable of transmitting thevirus to the newborn.