Estimation of parameters governing the transmission dynamics of schistosomes

The clumping parameter related to the distribution of schistosome parasites is obtained by fitting a negative binomial distribution to data collected from patients in a village in Brazil; the natural uninfected and parasite-induced snail host mortality rates are obtained from laboratory data. These values are used in a schistosomiasis model proposed earlier by the authors, and a disease transmission parameter from snails to humans is estimated. Finally, the effect of chemotherapy of humans is assessed using prevalence of morbidity as a measure of the level of schistosome infection in a human population.