A prevalence survey of nosocomial and community infections in a children's hospital was carried out in the wards of the Bambino Gesù Hospital, Rome, Italy. The overall prevalence of hospital-acquired infection (HAI) was 5.1%, with higher rates in surgical units and among children aged 1 to 5 years. The proportion of community-acquired infections was 9.2%, with higher rates in the infectious disease and internal medicine units and among children aged 6 to 11 years. The most frequent type of HAI was respiratory tract infection, with only a small number of urinary tract infections.