Application of new biogeographical tools for monitoring Trichinella sp. infection in wild boar (Sus scrofa) populations of central Spain

Abstract

In south-central Spain (SCS), the Eurasian wild boar harvest has increased in the last decades in association with more intensive management actions to increase hunting yields and consequent effects on wild boar health status. We investigated the spatial-temporal trend and the risk factors related to the prevalence of Trichinella sp infection in wild boar to obtain the annual probability of occurrence for these parasites in the Ciudad Real province of SCS. From 1998 to 2010, the mean prevalence for Trichinella sp by artificial digestion was 0.2% (0.17-0.23 95% CI) for the 95,070 examined wild boar. The presence of Trichinella sp infections in wild boar showed a decreasing trend during the study period, and was negatively related with fenced wild boar populations. Results revealed an absence of areas where Trichinella sp infection could be considered endemic, but also suggested that these parasites could occur sporadically in most of the study area. Risk maps based on biogeographical tools showed that even if the Trichinella sp endemic areas were very limited, most hunting estates presented favourable risk factor scores for these parasites at least during one of the studied hunting seasons. Thus, considering that human trichinellosis is still being reported yearly, application of new spatial epidemiology tools prove useful for risk factor assessment and for monitoring the parasite in wild boar populations over large spatial-temporal scales.