Leukemia patients to be given varicella vaccine

Abstract

Varicella vaccine, still experimental in this country, is being used in an effort to protect leukemia patients from potentially fatal chickenpox. The project eventually will involve 500 patients with acute lymphocytic leukemia who never have had chickenpox and lack antibodies to the varicella-zoster virus. An additional group of leukemia patients— those who have survived natural varicella infection without vaccination—are being recruited as controls. The National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Md, which is supporting the study, estimates that up to 7% of immunosuppressed leukemia patients who contract varicella will die. That estimate is largely based on treatment of 77 young cancer patients at St. Jude's Children's Research Hospital, Memphis. Sixty of these patients were immunosuppressed when they developed varicella; four died ( Pediatrics 1975;56:388-397). Among presumably healthy persons, the varicella death-to-case ratio recently in this country has been 6.7/10,000, according to data compiled by Stephen R. Preblud, MD,