Agent-based mathematical modeling as a tool for estimating Trypanosoma cruzi vector-host contact rates

The parasite Trypanosoma cruzi, spread by triatomine vectors, affects over 100 mammalian speciesthroughout the Americas, including humans, in whom it causes Chagas' disease. In the U.S., only a fewautochthonous cases have been documented in humans, but prevalence is high in sylvatic hosts (primar-ily raccoons in the southeast and woodrats in Texas). The sylvatic transmission of T. cruzi is spread by thevector species Triatoma sanguisuga and Triatoma gerstaeckeri biting their preferred hosts and thus creatingmultiple interacting vector-host cycles. The goal of this study is to quantify the rate of contacts betweendifferent host and vector species native to Texas using an agent-based model framework. The contactrates, which represent bites, are required to estimate transmission coefficients, which can be applied tomodels of infection dynamics. In addition to quantitative estimates, results confirm host irritability (inconjunction with host density) and vector starvation thresholds and dispersal as determining factors forvector density as well as host-vector contact rates.