One-year surveillance of legionellosis in burned patients and Legionella environmental monitoring

Burned patients have a theoretically high risk of Legionella infection because burns produce a compromised immune system. Cutaneous surfaces are without protective barriers, and bathing tank water is frequently used for washing and caring. A one-year surveillance study was performed on 65 burned patients by antibody determination and by culture of bronchial aspirates. Environmental culturing for Legionella was done in the patients' care areas every four months during the same period. Low titers ranging from 8 to 32 were found in 30 (46.1%) subjects against 18 antigens including several Legionella species. No increase in antibody titers was shown in 193 patients' sera. Cultures of respiratory samples were negative. L. pneumophila serogroups 4, 5, 6 and 8 and L. rubrilucens were isolated from 55.5% of water samples. Despite no evidence of Legionella infection among patients included in this study, the authors believe it to be advisable to improve control measures in hospital water supplies, used by burned patients, to minimise the risk of legionellosis.