Sentry surveillance study of rotavirus gastroenteritis in Chile A sentinel-based outpatient and inpatient surveillance for rotavirus infection has been implemented in Chile. Aim: Update the impact of rotavirus infections in Chile. Methods: Ambulatory surveillance is performed in 14 centers from 8 Regions and hospital-based surveillance in 8 hospitals from three Regions (V, VIII and Metropolitan). Results: In 2007, 339 stool samples that represented 9.3% of all outpatient cases were studied of which 15% were rotavirus positive. A total of 2.074 children younger than 5 years of age were hospitalized representing 9% of all hospitalizations for this age group. Rotavirus was detected in 13.6% of these cases. Conclusions: In the current epidemiological situation, rotavirus surveillance needs to be sustained with increased efforts to detect cases in order to avoid underreporting. Serotype/genotype surveillance of rotavirus strains needs to be included in the near future.