Exposure to Echinococcus multilocularis, Toxocara canis, and Toxocara cati in Austria: A Nationwide Cross-Sectional Seroprevalence Study

Despite emerging risks for the spread of zoonotic diseases, data on human exposure to Echinococcus multilocularis and Toxocara spp., the causative parasites of the two most important helminthozoonoses in Central Europe, are limited. To investigate risk factors and exposure, we conducted a nationwide, cross-sectional serological study in 1046 healthy individuals, of which 425 were soldiers and 621 were civilians. Serum samples and information on possible risk factors for exposure, including previous foreign military assignments, residential area, animal contact, and regular outdoor activities, were obtained. Immunoglobulin G antibodies against Echinococcus multilocularis and Toxocara spp. were examined with an enzyme-linked immunosorbent assay (ELISA). Samples reactive in the ELISA for antibodies against Echinococcus multilocularis were considered positive only after confirmation by western blot. Overall, 66 (6.3%) individuals tested positive in the serologic screening for Toxocara spp. Occupational animal contact was the only risk factor significantly associated with a higher risk for being seropositive. None of the individuals were positive for antibodies against Echinococcus multilocularis . In conclusion, the present study demonstrates that exposure to Toxocara spp. is widespread in Austria and occupational animal contact is a risk factor for seropositivity.