Nosocomial Influenza outbreak in an intensive-care unit

Objective - The authors investigated a nosocomial outbreak of pneumonia to determine the etiological diagnosis, to evaluate the transmission route, th e modalities of prevention, and the cost. Methods - All patients and staff members present in this acute-care unit ha d nasal wash, pharyngeal sampling and serological testing for detection of pneumonia agents. Epidemiological variables studied included influenza like illness, underlying disease and Influenza vaccine. The estimation of cost included excess days hospitalization, number of laboratory tests, medical i magery and treatment of patients, and sick leave days for staff category. Results - Investigation determined that it was an Influenza A outbreak, wit h nosocomial acquisition. Nine of 23 hospitalized patients (39%) and 5/22 ( 23%) staff members had Influenza A infection. Influenza vaccine was protect ive since the 11% (2/18) attack rate among the vaccinated persons of was si gnificantly lower (p = 0.03) than that of no-vaccinated persons [41% (11/27 )]. The influenza vaccine efficacy was 73%. The main over cost associated t o this outbreak was due to the excess days hospitalization and was estimate d to be of 222235 Francs. Conclusion - Vaccination of health care workers is essential to prevent nos ocomial Influenza spread and may represent important money savings. (C) 200 1 Editions scientifiques et medicales Elsevier SAS.