Survey for Trichinella spp. in red foxes (Vulpes vulpes) in Belgium

Concurrently with a survey for Echinococcus multilocularis in the red fox (Vulpes vulpes) in Flanders, northern Belgium, serological and parasitological analyses for Trichinella spp. were carried out from 1996 to 1999. Muscle samples from foxes in Wallonia, southern Belgium, were obtained during a survey for rabies and alveolar echinococcosis from 1998 to 2000. In muscle samples from tongue, diaphragm, hindlegs and tail of 179 Flemish foxes no larvae were found by trichinoscopy. Serum and muscle juice of, respectively 176 and 26 animals were examined using an ELISA for the detection of antibodies against excretory-secretory (ES) antigen. There were eight (4.5%) positive sera, but no positive muscle juice samples. All muscle samples from 639 foxes in Wallonia proved to be negative for larvae in artificial digestion. Serum and muscle juice of 130 and 478 foxes, respectively were examined in ES-ELISA. There were 61 (46.9%) positive sera and 90 (18.8%) positive muscle juice samples. A comparison between 88 serum and muscle juice samples of the same foxes showed that only half of the serum-positive animals were detected using muscle juice. However, for establishing the true meaning of these results, a more profound epidemiological study on the vulpine population in Belgium is necessary.