[Impact assessment of the rotavirus vaccine in Colombia using rapid evaluation methods]. / Evaluación del impacto de la vacuna contra rotavirus en Colombia usando métodos rápidos de evaluación.

ABSTRACT

OBJECTIVE: Estimate the effectiveness of the monovalent rotavirus vaccine in preventing the need to hospitalize children under 2 years old for acute diarrheal disease in five Colombian cities. METHODS: A population survey was conducted based on a probability sample of children over 2 months and under 24 months of age in five Colombian cities (Barranquilla, Bogotá, Cali, Cartagena, and Riohacha) over the period from August through October 2010. The vaccine had been introduced in the Expanded Program on Immunization in January 2009. Rotavirus vaccination coverage was estimated by age group; the cumulative incidence of hospitalization for severe diarrhea was determined; and the magnitude of correlation between vaccination with one or two doses of rotavirus vaccine and hospitalization for diarrhea was calculated using the age-adjusted probability ratio (PR) and other epidemiologically significant factors. Effectiveness of the vaccine was estimated using the expression 1-PR. RESULTS: Coverage with a single dose of the rotavirus vaccine was 87.3%. During the 12 months prior to the survey, 1 453 of the children under 24 months old in the study areas (43.2%) had presented with diarrhea, and of these, 174 (5.2%) had been hospitalized for this cause. The effectiveness of two doses of the vaccine in preventing hospitalization for severe diarrhea was 68% (CI 95% = 55%-77%). CONCLUSIONS: In Colombia, rotavirus vaccination protects against hospitalization for diarrhea due to any cause. The use of cross-sectional surveys appeared to be adequate for rapid evaluation of an immunization program's effectiveness with a new vaccine.