Within-year comparisons of the number of positive results for seven Leptospira serovars per host (Poisson regression) between host species, sex, and age. Raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana) blood samples were collected in 2008 and 2009 across Robert Allerton Park, Piatt County, Illinois, USA. Positive serovars per host could range between zero to seven (the total number of Leptospira serovars evaluated). Statistically significant differences (P<0.05) are indicated in bold.