Failure of Antepartum Maternal Cultures to Predict the Infant's Risk of Exposure to Herpes Simplex Virus at Delivery

Abstract

In 414 pregnant women with a history of recurrent genital herpes simplex infection, we studied the correlation between asymptomatic viral shedding in late pregnancy and at the time of delivery. Antepartum cultures for asymptomatic reactivation of herpes simplex virus were positive in 17 of the 414 women (4.1 percent). None of these women had positive cultures at the time of delivery. Cultures of specimens obtained at delivery from 5 of 354 asymptomatic mother-infant pairs (1.4 percent) were positive for asymptomatic excretion of herpes simplex virus. None of these women had had antepartum cultures that documented asymptomatic excretion of herpes simplex virus, despite the fact that culturing was repeatedly performed during the four weeks before delivery. Asymptomatic shedding of herpes simplex virus occurred with the same frequency at delivery, whether or not any episodes of symptomatic recurrence were noted during the pregnancy (1.4 vs. 1.3 percent). We conclude that antepartum maternal cultures do not predict the infant's risk of exposure to herpes simplex virus at delivery.

Neonatal Herpes Simplex Virus Infection

“…[21][22][23][24] In virologic surveillance of pregnant women with a known history of recurrent genital herpes, the rate of asymptomatic viral shedding at the time of delivery is as high as 1.4%, meaning that perinatal exposure of a newborn to HSV likely occurs more frequently than clinicians are aware. 25 Although the presence of active herpetic genital lesions or Neonatal Herpes Simplex Virus Infection asymptomatic shedding of virions are risk factors in themselves, recurrent HSV infection such as this still constitutes less of a risk for transmission of HSV infection to a newborn than does acquiring a new primary or first-episode infection near the time of delivery.…”

Guidelines for the management of herpes simplex virus in pregnancy

“…It is now clear that serial maternal antenatal cultures are not predictive of the development of neonatal herpes, and they are therefore not indicated [37,38].…”

Transport of viral specimens

“…Positive cultures were obtained when specimens on swabs were placed in tryptic soy broth and then held at 40C before and during transport (6,78). Nutrient broth (8), calf infusion broth (12, 39), brain heart infusion broth (78), and tryptose-phosphate broth with bovine serum albumin (79) were also used successfully.…”