Seroprevalence and risk factors of Toxoplasma gondii infection in invasive raccoons (Procyon lotor) in Central Europe

Toxoplasma gondii is an obligate intracellular protozoan that causes toxoplasmosis in warm-blooded animals. Most mammals, including humans, can become intermediate host, resulting in subclinical infection or even death. Generally, there is limited information on the epidemiology of T. gondii of game species in Germany. As omnivores, raccoons, which are particularly widespread and abundant in Germany, are particularly exposed to infection the parasite. Here, we report the seroprevalence of T. gondii antibodies from 15 study sites located in Luxembourg and Germany. Using the indirect modified agglutination test (MAT), 170 (37.4%; 95% CI: 33.0–41.9) out of 454 raccoons were surveyed to be T. gondii seropositive. While values ranged from 19.0% to 53.3%, there was no significant difference in seroprevalence between study areas. Animal weight had a strong influence on the presence of T. gondii antibodies in raccoon sera, with heavier animals more likely to be seropositive. Our results show that T. gondii infection is widespread in central European raccoons, suggesting a high degree of ecosystem circulation of the parasite.