Neonatal herpes is a rare but potentially devastating complication of genital herpes during pregnancy, which can cause brain damage, breathing problems, seizures and even death. Neonatal herpes infection can occur when an infant is exposed to herpes simplex virus types 1 or 2 (HSV-1 or HSV-2) in a woman’s genital tract during birth.


For the first time, researchers from WHO, the University of Bristol, and the University of Washington have published new estimates in The Lancet Global Health that aim to evaluate the approximate global burden of this disease.

According to the estimates, there were approximately 14,000 cases of neonatal herpes annually during 2010 to 2015; the overall rate was estimated to be around 10 cases per 100,000 live births worldwide. The authors noted that they likely underestimated the number of cases in resource-poor settings, where data on neonatal herpes were limited.

Worldwide, most genital herpes is caused by HSV-2, which is sexually transmitted. HSV-1 is typically transmitted orally (causing oral herpes or “cold sores”). HSV-1 can also be transmitted to the genital area through oral-genital contact to cause genital herpes.

The risk for neonatal herpes is greatest when a woman acquires genital HSV infection for the first time in late pregnancy. Women who have genital herpes before they become pregnant are at very low risk of transmitting herpes to their infants.