Toxoplasma gondii seroprevalence in veterinarians in Finland: older age, living in the countryside, tasting beef during cooking and not doing small animal practice associated with seropositivity.
Practising veterinary medicine has an inherent risk of exposure to zoonotic agents, including the protozoan parasite Toxoplasma gondii. We screened sera of veterinarians authorized to work in Finland for the presence of specific immunoglobulin G antibodies against T. gondii with an enzyme-linked fluorescent assay, and evaluated potential risk factors for T. gondii seropositivity from extensive questionnaire data with almost 1,300 quantitative variables. We used a causal diagram approach to address the complexity of the life cycle of the parasite and its numerous possible transmission routes, and built a multivariable binomial logistic regression model to identify risk factors that are particularly relevant for veterinarians. The samples and questionnaire data were collected in 2009. Altogether, 294 veterinarians, almost 15% of the Finnish veterinary profession, were included in the study. The median age was 39 years, and the majority, 86%, were women. Altogether, 43 (14.6%; 95% confidence interval: 10.9-19.0) of the 294 veterinarians tested seropositive for T. gondii. According to the final model, veterinarians who were at least 40 years old had 2.4 times higher odds to be seropositive than younger veterinarians; veterinarians who lived in the countryside had 4.0 times higher odds to be seropositive than veterinarians who lived in towns; female veterinarians who tasted beef during cooking had 2.6 times higher odds to be seropositive than male veterinarians who did not taste beef during cooking; and veterinarians who did not do small animal practice had 2.3 times higher odds to be seropositive than those who did. The results illustrate the numerous transmission routes of T. gondii.