Abstract

Since 1998, the state of Rio Grande do Sul, Brazil, had been free of foot-and-mouth disease (FMD) with yearly mandatory vaccination until the reintroductions of the disease in 2000 and 2001. This study gathered data from both outbreaks from official veterinary state service archives and field investigation reports. The purpose was to quantify epidemiological parameters, such as epidemic duration and the number of secondarily infected farms and animals, which are necessary for estimating outbreak dynamics. The researchers applied a Bayesian latent variable approach using back-calculation to estimate the time-varying reproduction number and calculate the number of new confirmed cases by infection date. This approach allowed for the estimation of transmission parameters of the 2000 and 2001 FMD outbreaks in the State of Rio Grande do Sul, Brazil.