Paratuberculosis is the most serious chronic bacterial disease of ruminants. Regarding the increasing incidence of the disease in the Czech Republic in connection with changing situation in agriculture and, among other factors, with import of animals we are presenting a summary of the latest data. We assume that high economic losses and expected participation of Mycobacterium paratuberculosis in Crohn's disease in men will evoke a broad interest in the disease among people from various branches of veterinary and human diagnosis.