Factors associated with endemic raccoon (Procyon lotor) rabies in terrestrial mammals in New York State, USA.

This study evaluated characteristics associated with raccoon (Procyon lotor) rabies in New York State (NYS), USA, where this disease has been endemic for the last 15 years. The study included 4448 cases of raccoon rabies in terrestrial mammals reported across 1639 census tracts of NYS during 1997-2003. A Poisson-regression model with census tract-year as the unit of analysis revealed a higher number of raccoon-variant rabies cases per square kilometer in census tracts with each percent increase in the proportion of low-intensity residential areas (those with a lower concentration of housing units) (RR=7.68) and a lack of rivers/lakes (RR=1.20) and major roads (RR=1.10), while the number of cases decreased with each 1-m increase in land elevation (RR=0.998), and each percent increase in the proportion of wetlands (RR=0.01). The model was adjusted for county, ecoregion, and latitude to help control for unknown spatially dependent covariates. The model may be used in prioritizing areas for rabies control based on differential risk, including use of costly intervention methods such as oral rabies vaccine.