A live varicella vaccine in a pediatric community.

A total of 663 children with various underlying diseases were immunized with a live varicella vaccine at the vaccine clinic of Osaka University Hospital during a period of seven years from October, 1975. Clinical reactions after vaccination occurred in 32.4% (24/74) of the children with malignancies and in 0.3% (2/591) of those in other groups. Vaccine-induced immunity was detected for more than 6 years, by FAMA (fluorescent antibody to membrane antigen) and IAHA (immune adherence hemagglutination) tests, and a skin-test for varicella-zoster virus (VZV). During an observation period of more than 7 years, clinical varicella developed in 12 children, 8 of whom were in the group with malignancies. Zoster occurred in only 4 (9.1%) of 44 vaccinees with acute leukemia, this incidence being significantly less (p less than 0.05) than that (21.6%, 8/37) in un-vaccinated leukemic children.