Analysis of theIncidence of Tularaemia in the Břeclav District in 1994–1999

Overview

Moravia is one of the areas where there are long-term natural foci of tularaemia. In 1994in the Břeclav district an exacerbation of the disease was recorded in hares. During autumn huntsa positive reaction was recorded in 5.75% of examined hares. An elevated seropositivity persistedalso in subsequent years and at the same time a higher human morbidity in the mentioned region.The objective of the investigation was to assess the causes and circumstances which led to theexacerbation of old known but in recent years quiescent foci in the mentioned region. To this end350 small terrestrial mammals were examined. In one case it proved possible to detect the causalagent in Microtus arvalis. By examination of arthropods it proved possible to isolate 33 strains, i.e.32 strains from ticks Dermacentor reticulatus and one strain from Ixodes ricinus. The results of theexamination revealed that tularaemia as a classical infection with a natural focus may persist inareas where there are prerequisites for survival of the causal agent in the environment. One of theimportant factors of the environment are susceptible individuals (hares, small terrestrial mammals)as well as blood sucking arthropods as vectors of the disease.

Key words:
tularaemia – Francisella tularensis – hare-ticks – southern Moravia.