SPATIAL-DISTRIBUTION PATTERNS OF ECHINOCOCCUS-MULTILOCULARIS (LEUCKART 1863) (CESTODA, CYCLOPHYLLIDEA, TAENIIDAE) AMONG RED FOXES IN AN ENDEMIC FOCUS IN BRANDENBURG, GERMANY

Over a period of 40 months, 4374 foxes were randomly sampled from an a rea located in northwestern Brandenburg, Germany, and examined parasit ologically for infections with Echinococcus multilocularis. Spatial an alysis of the origin of infected animals identified two (one central a nd one southeastern) high-endemic foci with an estimated prevalence of 23.8 %. By contrast, a prevalence of 4.9 % was found in the remaining (low-endemic) area. The prevalences among juvenile and adult foxes we re compared in the high-endemic and the low-endemic areas. To analyse the central high-endemic focus further, the random sample was stratifi ed by zones representing concentric circles with a radius of 13 km (zo ne 1) or x(n-1) +7 km for the remaining three zones from the apparent centre of this focus (anchor point). Prevalences calculated for each z one showed a decrease from zone 1 (18.8 %) to zone 4 (2.4%) with signi ficant differences for all zones but zones 3 and 4. The relative risk of an infection decreased rapidly in a distance range of 26 km around the high-endemic focus, whereas the relative risk remained unchanged w ithin a distance of 5 km around the anchor point. The importance of he terogeneous spatial distribution patterns for the diagnosis and epidem iology of the infection is discussed.