The burden of rotavirus diarrhea in khanh hoa province, Vietnam - Baseline assessment for a rotavirus vaccine trial

Background: In Vietnam, rotavirus is seen as a priority disease because studies have demonstrated that > 50% of children hospitalized for treatment of diarrhea have rotavirus as the pathogen. To anticipate the availability of new vaccines, we have examined our field area in Nha Trang, Khanh Hoa Province, Vietnam, as a potential site to conduct a field trial of a future rotavirus vaccine. Methods: Data from a population census, incidence rates of diarrhea from a previous cholera vaccine trial and hospitalization rates from computerized records collected from the 2 main hospitals in the province were reviewed to estimate the burden of rotavirus-related diarrhea that might be expected during a field trial of a rotavirus vaccine. Results: For a birth cohort of similar to 5000 children, we would expect similar to 2500 clinic visits and 650 - 850 hospitalizations for treatment of diarrhea, of which similar to 375 - 425 would be attributable to rotavirus. For the Vietnamese birth cohort of 1,639,000 children, these numbers translate into similar to 820,000 clinic visits, 122,000 - 140,000 hospitalizations and 2900 - 5400 deaths annually attributable to rotavirus-related diarrhea. Conclusions: Vietnam is an early adaptor of new vaccines, has high national coverage rates (> 85%) for childhood immunization and receives international donor support for the introduction of new vaccines. We found the epidemiologic features of rotavirus in rural Vietnam to be more similar to those of rotavirus in a developed country than to those of rotavirus in India or Bangladesh.