Young mothers most likely to give their babies herpes
Herpes Simplex Virus (HSV) has emerged as a more common threat to infant health than congenital rubella, syphilis or perinatal HIV, according to a nationwide study.
Data drawn from the Australian Paediatric Surveillance Unit and analysed by University of Sydney researchers has in the past 15 years identified 131 cases of neonatal HSV infection – 24 of which proved fatal.
Though the incidence of neonatal HSV infection is rare, the study’s lead author Professor Cheryl Jones, of the Sydney Medical School, said it was significantly more common in children born to mothers younger than 20 years of age, and was more likely in babies of low birth weight and those born pre-term.
The study found that mothers younger than 20 years were four times more likely than the general population to give birth to babies infected with neonatal HSV.
Neonatal HSV, though rare, can be serious and even deadly. Apart from sores and lesions, it can cause encephalitis and, if left untreated, may infect multiple organs and glands, with often severe consequences.
“Without antiviral therapy, death or handicap is almost inevitable after disseminated or central nervous system disease,” Professor Jones said, though her study found that the mortality rate from neonatal HSV infection had dropped off in recent years.
Babies typically catch HSV from their mothers during delivery, but they can also be infected through contact following birth.
It has been speculated that caesarean delivery might reduce or prevent transmission of HSV from mother to baby, but Professor Jones’ study, published in the journal Clinical Infectious Diseases, found that a third of all infected infants were born by caesarean.
The study found that the overall rate of neonatal HSV infections was relatively stable over 15 years, but the prevalence of HSV-1 has increased relative to HSV-2.
Though both are ubiquitous and contagious, historically HSV-1 has been most commonly associated with cold sores, while HSV-2 has been responsible for most cases of genital herpes.
Globally, however, there has been an increase in genital herpes caused by HSV-1, including in Australia, and Professor Jones’ study has found that HSV-1 has displaced HSV-2 as the leading form of neonatal HSV infection.
“This increase (in HSV-1 genital herpes infections) has been most marked in young women, and is consistent with our findings of an over-representation of adolescent mothers in this study,” Professor Jones said. “The reasons for this increase are unknown, but preventive efforts should include increasing adolescent awareness of sexually transmitted infections like HSV.”