Human as a potential vector of bovine tuberculosis in cattle

Introduction and objectiveBovine tuberculosis (bTB, bovine TB) is caused by mycobacteria which are grouped within the MTBC. TB in animals is a highly infectious and progressive disease which can be transmitted to humans. Since 2009, Poland has gained official bTB-free status. Despite the official fact of bTB-free status, a dozen bTB outbreaks are still noted each year. Since 2000 in Poland, every year 1/5 of the national herd is subject to intradermal skin TB testing to control the bTB outbreaks in the cattle population. Application, with 5-year intervals between each government-funded skin test, undoubtedly resulted in financial savings. However it also seems to have caused several adverse and worrying events, e.g. an increase in the number of reactors detected and removed from a single tested herd. The objective of this study was the examination of 898 cattle imputed with bTB infection in Poland between 2008–2012.Material and methodsThe study concerned a potential epidemic outbreak with suspected bTB transmission. 20 cows came from 3 herds in the same county located in the same province in southern Poland.Results134 MTBC strains were identified. In MIRU-VNTR, all isolates showed the same genetic pattern 322532243421232. Based on molecular investigation, the characteristics of M. bovis strains isolated from cattle from 3 different herds confirmed the common source of this zoonotic disease.ConclusionsAlthough not bacteriologically proven, everything points to the fact that humans were the vector of bovine tuberculosis transmission between herds. This finding confirms transmission between 3 cattle herds in the Małopolskie Province in southern Poland (Podhale). The outbreak of tuberculosis in animals finally compromised public health.