This is a randomized, double-blind effectiveness trial of a bivalent, killed oral cholera vaccine developed in Vietnam. The trial will be conducted in the Khanh boa Province of Vietnam The general aim of the trial is to simulate a public health program of vaccination against cholera and to estimate the costs and effects of this vaccination strategy. Specific objectives are to assess the impact of vaccination on the incidence of cholera and on the overall incidence of treated episodes of diarrhea; to evaluate the cost-effectiveness of this vaccine; and to assess community beliefs about vaccines and the prevention of cholera, as well as the community's experience with vaccination and reasons for non-vaccination.
