Flow diagram of the mathematical model of cholera transmission.

<p>Individuals are aggregated in compartments by cholera status as susceptible unvaccinated (S), susceptible vaccinated (V), cholera cases (I), asymptomatically infected (A), and recovered (R). The concentration of <i>Vibrio cholerae</i> in the environment is tracked in a separate compartment (W). Proportion <i>p</i> of the susceptibles and proportion <i>q</i> of the vaccinated who become infected are symptomatic (cholera cases), and a fraction <i>r</i> of these are reported and used to fit the model to surveillance data. Infected individuals shed bacteria into the environment and cause indirect transmission of Cholera (dashed lines). The simulated population is additionally stratified by age (not shown). A complete description of the model including the expressions for the forces of infections (λ and λ^V) is presented in <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003343#pntd.0003343.s001" target="_blank">Text S1</a>.