We performed a retrospective analysis of longitudinal clinical and immunologic data obtained from 22 children in the early stages of infection with human immunodeficiency virus (HIV) when they developed varicella. We studied the course of HIV infection to determine whether clinical deterioration occurred after chickenpox. We examined the following indices: growth and development; neurologic status; helper T lymphocyte counts; blood values of core (p24) antigen of HIV; changes in the stage of HIV infection; and need for administration of zidovudine. We studied children for a mean of 2.8 years and for as long as 9.8 years after onset of varicella. There was little evidence that chickenpox affected HIV infection. Three (14%) children developed clinical zoster, 2 of whom (9%) had evidence of chronic infection with varicella-zoster virus. One additional child (5%) had 2 episodes of chickenpox. These observations suggest that children with early HIV infection could be considered for immunization with live attenuated varicella vaccine, which would be predicted to decrease their morbidity from varicella-zoster virus.