The effect of seasonality, climate, and density on hantavirus dynamics in the deer mouse in Montana

Background/Question/Methods: Since hantavirus was first discovered in the U.S. in 1993, the Centers for Disease Control and Prevention have sponsored longitudinal studies on the rodent reservoir host, the deer mouse (Peromyscus maniculatus). These studies have demonstrated a qualitative correlation among mouse population dynamics, incidence of hantavirus in the mouse reservoir host, and risk of hantavirus pulmonary syndrome infection in humans. Using capture-mark-recapture statistical methods on a ten and a half year dataset from Montana, we estimated deer mouse demographic and hantavirus transmission rates, and tested the relative importance of seasonality, density and climate in explaining temporal variation in these rates. From these estimates we designed a stage-based SIR (Susceptible-Infected-Recovered) model to simulate deer mouse population and hantavirus dynamics given climatic variables, and the model output was compared to observed patterns.

Results/Conclusions: Results show that month, precipitation, temperature, and density at several time lags, and their interactions are important in determining deer mouse survival, recruitment, and maturation rates. These, in turn, affect the hantavirus dynamics in the disease reservoir host, the deer mouse. Understanding the population and hantavirus dynamics of reservoir hosts may allow public health officials to predict increased human risk and effectively target prevention strategies.