Deaths from varicella in infants.

Onset of maternal varicella up to 5 days before delivery is associated with in utero exposure to varicella and may result in severe infection in the newborn 5 to 10 days after delivery. Since up to 31% of these newborns may die, routine administration of varicella-zoster immunoglobulin to these infants is recommended. Little is known, however, about the risk of death in other infants with postnatal infection. Available epidemiologic data indicate an estimated death/case ratio for children less than 1 year of age 4 times that for 1- to 14-year-olds (8 in 100,000 vs. 2 in 100,000). Since the actual ages for the infant deaths were lacking, it has been impossible to know how many deaths were possibly related to maternal varicella contracted within the 5 days before delivery. Using National Center for Health Statistics data, we analyzed 92 deaths due to varicella in children less than 1 year old reported between 1968 and 1978 (median age, 5.5 months). Only five deaths occurred in newborns (ages 8 hours to 19 days). These data indicate that intrauterine infection accounts for few varicella deaths in infants. Since postnatal infection accounts for the observed increased risk of death in this age group, the need for preventing postnatal varicella in all infants merits further study. However, based on the small number of deaths occurring annually and the low relative risk compared to other high risk groups, routine postexposure administration of varicella-zoster immunoglobulin to all children less than 1 year of age does not seem warranted at this time.