Transmission of varicella-zoster virus from a vaccinee with leukemia, demonstrated by polymerase chain reaction.

A 5-year-old white boy in remission from acute lymphoblastic leukemia who was receiving maintenance anticancer chemotherapy had approximately 200 vesicular skin lesions 1 month after receiving live attenuated varicella vaccine. About 2 to 3 weeks later, a mild illness resembling varicella occurred in his susceptible siblings and in three of his classmates. Vaccine-type varicella-zoster virus was demonstrated by polymerase chain reaction in swab specimens from vesicular lesions in his two siblings, in whom antibody to varicella-zoster virus also developed.