INFESTATION OF WATER VOLES (ARVICOLA-TERR ESTRIS) WITH METACESTODES OF ECHINOCOCCUS-MULTILOCULARIS IN THE CANTON OF FREIBURG (SWITZERLAND)

The results of an investigation on Echinococcus multilocularis-metaces todes in European water voles (Arvicola terrestris) are shown. The inv estigation materials were 28 water voles captured in Schermann-traps o n a meadow in the canton of Fribourg and subsequently maintained in la boratory cages. The animals were patho-anatomically and histo-patholog ically examined, a part of them additionally with an E. multilocularis -specific direct immunofluorescence-assay and/or a polymerase-chain-re action. Radiographs were obtained from one animal, showing typical cal cifications as they often occur with alveolar echinococcosis. Alltoget her 11 out of 28 (39%) animals proved to be infected with E. multilocu laris. As far as we know this represents the highest percentage of inf estated intermediate hosts ascertained in Europe. However, fertile, i. e. able to infect, protoscolices were detected in only two cases. In s pite of this small number of protoscolices it can be shown that A. ter restris is able to maintain the lifecycle of this cestode at least spa tially and temporally limited. In conclusion the possible measures for reducing the infection risk of the people in the affected community a re shortly discussed.