Seroprevalence of Toxoplasma gondii in domestic pigs (Sus scrofa domestica) and wild boars (Sus scrofa) in Latvia

Consumption of undercooked pork products is considered a major risk factor for contracting toxoplasmosis in humans in several countries. In total, 803 pork samples and 606 wild boar meat samples were collected from different regions of Latvia during June 2010 and February 2011 were tested for Toxoplasma gondii antibodies using an in-house ELISA assay. Seroprevalence in wild boar (33.2%, P < 0.05) was significantly higher than in domestic pig (4.2%). The prevalence of T. gondii-specific antibodies was greater in free-ranging domestic pigs (6.2%, P < 0.05) than those that were intensively farmed (0.4%). Animals from free-range farms had 17.6 times higher odds ratio (OR) (95% confidence interval [CI]: 2.4-129.8) for the presence of specific T. gondii antibodies than animals from intensive farms. The OR (95% CI: 1.1-2.7) of feral wild boars for T. gondii-specific antibodies was 1.7 times higher than for farmed wild boars. Our findings indicate that the prevalence of T. gondii infection was higher for animals with open access to wildlife and direct contact with environment. This is the first report of T. gondii prevalence in pigs in Latvia.