Suburban white-tailed deer seropositive for Toxoplasma gondii from Chicago, Illinois

The presence and abundance of vertebrates influences the circulation of zoonotic diseases. White-tailed deer ( Odocoileus virginianus ) are widely distributed in North America and deer densities are frequently high in unhunted areas, including most major metropolitan regions. This study investigated the seroprevalence for Toxoplasma gondii from live-captured and culled deer sampled in two suburban forest preserves around Chicago, Illinois, from 1995 to 1999. Seroprevalence for T . gondii was 55.9% ( n = 443) and was significantly higher at the northern study site, Des Plaines. Seroprevalence for T . gondii varied by year and month. Multivariate logistic regression (LR) screened main effect variables (age, sex, site, year, and month) by backward stepwise elimination. The final LR model for T . gondii contained all main effect variables. This study provides baseline data for future T . gondii suburban deer studies and information to public health and wildlife officials regarding the prevalence a parasitic pathogen present in two public forest preserves in Chicago, Illinois.