The prevalence of Trichinella infection in domestic dogs in Finland

In this study, we examined the prevalence of Trichinella infection in domestic dogs in Finland, which is known to have a high prevalence of Trichinella infection in sylvatic hosts. Altogether 727 dog serum samples were tested serologically by ELISA with ES-antigen in dilutions 1:50, 1:100, 1:200, and 1:400. Additionally, muscle samples from 102 dogs' front leg extensors were tested parasitologically by HCl-pepsin-digestion. The tested dogs originated from the University Veterinary Hospital (244 of the sera and all of the parasitologically tested muscle samples) and from a serum bank of the National Veterinary and Food Research Institute (465 serum samples), representing healthy dogs mostly from southern Finland. As negative controls, we tested sera from 18 experimental dogs known to be negative for Trichinella infection. Trichinella spp. was isolated from one dog (1%) with a low infection intensity. High OD% were found in both groups of serum samples. Of the hospitalized dogs, 4.9% were classified positive, and 8.6% of the healthy dogs were classified positive (7.3% in total). The sex or breed of the tested dogs did not correlate with the positive results, but the age correlated positively in the serum bank group. The serological results suggest that dogs may be exposed to Trichinella spp. in Finland; however, confirmation of low-level infections requires confirmation by direct testing methods.