Herpes simplex virus infection uncommon in infants assessed for meningitis
Infection with herpes simplex virus (HSV) occurs rarely in young infants undergoing meningitis evaluation, with the prevalence peaking in the second week of life and declining substantially in the second month of life, a study reports.
Researchers examined 26,533 infants (median age 28 days; 44.2 percent female) who had undergone cerebrospinal fluid culture testing in one of 23 participating emergency departments. The proportion of encounters in which HSV infection (defined by a positive HSV polymerase chain reaction or viral culture) was identified was the primary outcome. Secondary outcomes included frequency of central nervous system (CNS) and disseminated HSV, and HSV testing and treatment patterns.
There were 112 HSV infections identified (0.42 percent; 95 percent CI, 0.35–0.51), and the median age of infected infants was 14 days (interquartile range, 9–24). Of the HSV cases, 90 (80.4 percent) occurred in weeks 1 to 4, 10 (8.9 percent) in weeks 5 to 6, and 12 (10.7 percent) in weeks 7 to 9. HSV infection was four times more likely to occur in 0–28-day-old infants than in 29–60-day-old infants (odds ratio, 3.9; 2.4–6.2).
Overall, 68 infants (0.26 percent) had CNS or disseminated HSV. The proportion of infants tested for HSV was 35 percent (range, 14–72) and to whom acyclovir was administered was 23 percent (range, 4–53), and this varied widely across sites.
“Our data emphasize the need for improved management strategies focused on the early identification of infants at both high and low risk of HSV infection,” researchers said.
More studies are needed to identify clinical and laboratory factors that can aid HSV infection risk stratification to enable the accurate identification of infants at high risk and in need of empirical HSV testing and treatment, while minimizing the testing and treatment of low-risk infants, they added.