Seroprevalence and factors associated with Toxoplasma gondii infection in wild boar (Sus scrofa) in a Mediterranean island

INRA, UR 346 Epidémiologie Animale, Theix, France.
Epidemiology and Infection (Impact Factor: 2.54). 09/2010; 138(9):1257-66. DOI: 10.1017/S0950268810000117
Source: PubMed


Knowledge of the factors affecting the presence of Toxoplasma gondii in wildlife is limited. Here we analyse which local landscape characteristics are associated with the presence of toxoplasmosis in wild boar, Sus scrofa, on the island of Corsica, France. Meat juice samples from 1399 wild boars collected during two hunting seasons were tested for T. gondii antibodies using the modified agglutination test (titre 1:4). The overall seroprevalence was 0.55 (95% CI 0.50-0.59) for the first year and 0.33 (95% CI 0.29-0.35) for the second year. Seroprevalence varied according to age and county. At the county level, seropositivity in adults was related to farm density during year 1, and to habitat fragmentation, farm density and altitude during year 2. The exposure of wild boar to T. gondii is thus variable according to landscape characteristics and probably results in a variable risk of transmission of toxoplasmosis to humans.

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    • "In contrast, we showed that antibody prevalence was positively related to farm density in adults. Our approach was similar to that of Richomme et al. (2010), who showed that T. gondii seroprevalence in the wild boar (Sus scrofa) was related to farm densities within sampling communes. The commune, as a scale of investigation, does not have any significance for the ecology of the three types of cats (as home range size estimated from radiocollared individuals ranged from 2 to 220 ha for domestic cats and from 122 to 404 ha for Fig. 3. Predicted relationships between NAO winter index and the probability of seropositivity for Toxoplasma gondii in all cats sampled; (a) juveniles and (b) adults. "
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