Varicella vaccination in children with lymphoma and solid tumours

Background: Varicella infection can be a severe disease, especially in immunosuppressed patients. Here, experience with live varicella vaccine to prevent varicella infection is reported in children who were undergoing treatment for lymphoma and solid tumours. Methods: 40 children, aged between 12 months and 15 years with no clinical history of varicella, were vaccinated with live varicella vaccine. All received two doses of the vaccine subcutaneously 4 weeks apart. Serum samples were taken before the first dose and 6 weeks after the second dose of vaccine. Results: Before vaccination, 32 patients were seronegative for varicella and eight were seropositive. Seroconversion was observed 6 weeks after the second dose in 24 of the 32 (75%) seronegative children. In 4 of 8 previously seropositive patients, antibody titres increased after immunisation. Zoster infection occurred 5 weeks after the second dose of vaccine in only one previously seronegative child. 7 children, who had responded to the vaccine, have been exposed to varicella in their families or in school without contracting clinical disease. Conclusion: Although the small number of patients in our group prevents us from drawing definitive conclusions, the varicella vaccine seems to be well tolerated and can be administered to children with lymphoma and solid tumours undergoing treatment.