Up close: Congenital and perinatal viral infections

Neonatal viral infections are four to eight times more common than systemic bacterial diseases, but often go unrecognized. “Congenital cytomegalovirus (CMV) is one of the most common causes of infant death and permanent disability in America,” said Michael Cannon, PhD, Centers for Disease Control and Prevention, Atlanta.

Although congenital CMV can lead to hearing loss, vision loss and mental retardation, the disease is largely asymptomatic in newborns. Valacyclovir and CMV hyperimmune globulin may reduce sequelae, but prevention is the most effective strategy. Young children can actively shed the virus for months or years, so good hygiene after diaper changes, feeding, and bathing can help prevent transmission to a pregnant woman.

Herpes simplex virus is another seldom-recognized problem. “About 25% of pregnant women are already infected with HSV-2,” said Lawrence Stanberry, MD, University of Texas Medical Branch, Galveston. Mothers with active infections are most likely to transmit the virus, but 90% of these women are asymptomatic. Intravenous acyclovir is the only approved treatment for babies.

“Hepatitis B is on the decline in the US due to vaccination,” said Susan Schuval, MD, Schneider Children’s Hospital, Great Neck, NY. The news, however, is less positive for Hepatitis C. No vaccine exists and population trends point to an increase in pediatric disease in coming years. Dr. Schuval recommended newborn screening if the mother is HIV positive or at high risk due to injection drug use of some other factor. If the baby is positive, interferon and repairing are the only drugs approved for use in children younger than three.

Neonatal HIV is also on the decline in the U.S. Mother-child transmission is the primary etiology of pediatric HIV infections, noted Jennifer Read, MD, National Institutes of Health, Bethesda. Because HIV is nearly 100% fatal, prevention is a key strategy, adds Dr. Read. Women with any detectable HIV viral load should be on antiretrovirals to reduce the risk of transmission to the child. Cesarean section before membrane rupture reduces the likelihood of transmission. HIV-positive women should also be advised to avoid breast feeding to further reduce the risk of transmission.