A model for the transmission of Echinococcus multilocularis in Hokkaido, Japan.

A mathematical model for Echinococcus multilocularis transmission would be useful for estimating its prevalence and determining control strategies. We propose a mathematical model which quantitatively describes the transmission of E. multilocularis in Hokkaido, Japan. The model takes into account the influence of the dynamics of both the definitive and the intermediate host populations, which show large scale seasonal variation as they are wild animals. The simulations based on the model clarify the mechanism of seasonal transmission of E. multilocularis quantitatively, notwithstanding a lack of seasonal prevalence data. At present, human alveolar echinococcosis is prevalent throughout the mainland of Hokkaido. The risk of being infected in the human population has been investigated by analyzing the seasonal fluctuation in parasite egg dispersion in the environment. This is necessary for the planning of more suitable preventive measures against E. multilocularis.