Active hospital-based surveillance of rotavirus diarrhea in Austrian children, period 1997 to 2003.

BACKGROUND: Rotavirus is the most common pathogen causing severe dehydrating diarrhea in infants and young children worldwide. Any decision on implementation of rotavirus vaccination will be strongly influenced by the expected reduction in severe and therefore costly outcomes associated with rotavirus infection. The aim of this study was to provide data on hospitalization of young children with rotavirus infection in Austria. METHODS: The data were derived from active hospital-based sentinel surveillance for rotavirus during the period 1997 to 2003. RESULTS: During this period 25,600 children<15 years of age were hospitalized with acute laboratory-confirmed rotavirus gastroenteritis, the infection showing seasonal peaks between February and March. In 5 % of the cases first symptoms of diarrhea occurred at a minimum of 48 hours after hospital admission, indicating healthcare-associated origin of infection. The mean annual incidence of hospitalization per 100,000 population for the age group<5 years was 766 and for those<2 years 1742, the latter meaning that 1 in 60 Austrian children up to 2 years of age required hospitalization. An average peak incidence was observed between 8 and 14 months of age, with an average of 68% of the reported cases occurring in children aged