Serological Evidence of Exposure to Globally Relevant Zoonotic Parasites in the Estonian Population

We investigated Estonian population and its selected subgroups for serological evidence of exposure to Ascaris lumbricoides, Echinococcus spp., Taenia solium, Toxocara canis, Toxoplasma gondii, and Trichinella spiralis. Serum samples from 999 adults representing general population, 248 children aged 14-18, 158 veterinarians, 375 animal caretakers, and 144 hunters were tested for specific immunoglobulin G antibodies against the selected parasites using commercial enzyme immunoassays (ELISA). Sera yielding positive or twice grey zone Echinococcus spp, T. solium, T. canis, and T. spiralis results were subjected to western blot (WB) analysis. In the general population, based on the ELISA results, the A. lumbricoides seroprevalence was 12.7%, Echinococcus spp. seroprevalence was 3.3%, T. solium seroprevalence was 0.7%, T. canis seroprevalence was 12.1%, T. gondii seroprevalence was 55.8%, and T. spiralis seroprevalence was 3.1%. Ascaris lumbricoides seroprevalences were higher in children and in animal caretakers than in the general population, and T. canis seroprevalence was higher in animal caretakers than in the general population. Compared with the general population, Echinococcus spp. seroprevalence was higher in children. By contrast, T. gondii seroprevalence was higher in animal caretakers, and lower in children, than in the general population. In the general population, the WB-confirmed Echinococcus spp. seroprevalence was 0.5%, T. solium cysticercosis seroprevalence was 0.0%, Toxocara spp. seroprevalence was 14.5%, and Trichinella spp. seroprevalence was 2.7%. WB-confirmed Toxocara spp. seroprevalence was higher in animal caretakers than in the general population. We found serological evidence of exposure to zoonotic parasites in all tested groups. This calls for higher awareness of zoonotic parasitic infections in Estonia.