A geographic information system was used for the analysis of ecological conditions of distribution of natural foci of brucellosis in the European hare (Lepus europaeus) and their long-term persistence in the Czech Republic. The European hare is a reservoir host of Brucella suis biotype 2. A close correlation was found between the geographic distribution and numbers of natural foci of brucellosis in the Czech Republic in 1971 to 1985 and 1986 to 2000 (r = 0.65, n = 814, P = 0.01). Natural foci of brucellosis were persistent, but not stationary, over the period of 30 years. Natural foci of brucellosis were most abundant in habitats of beech forests and the mosaic of fields and forests (x<sub>b</sub> = 3.19 and 2.95, respectively), geographic areas of 201–400 m of elevation above sea level (x<sub>b</sub> = 2.53), 0.0–2.0°C of mean annual air temperature (x<sub>b</sub> = 3.62), 1 401–1 800 mm of mean annual precipitation (x<sub>b</sub> = 4.52), 1 601–1 800 h of mean annual sunshine duration (x<sub>b</sub> = 2.64), and areas of the European hare population density of 51–100 individuals per 10 km<sup>2</sup> (x<sub>b</sub> = 3.33). Natural foci of brucellosis seem to be independent of the population density of European hare.
Ecology of brucellosis of the European hare in theCzechRepublic