Reservoir host community and vector density predict human tick-borne
diseases across the eastern United States
Abstract
Tick-borne disease (TBD) incidences are rising globally, highlighting
the need for effective prevention strategies that consider the
ecological context of disease transmission. We analyzed the relationship
between human prevalence of four TBDs in the eastern U.S. and various
ecological and climatic factors. Babesiosis showed a negative
relationship with mean annual temperature, while ehrlichiosis exhibited
no significant associations. Anaplasmosis prevalence was positively
linked to nymphal tick densities, with competent host abundance
mediating the relationship between prevalence and small mammal richness.
Lyme disease prevalence correlated positively with densities of ticks,
infected ticks, deer, and reservoir hosts, while negatively correlating
with precipitation, temperature, and small mammal richness. We expand on
the dilution effect in Lyme disease by linking reservoir hosts, tick
density, and human cases at broader scales. Our findings suggest that
TBD intervention efficacy may vary based on tick and host dynamics,
underscoring the importance of ecological context in designing effective
strategies.