Molecular characterisation of the Mycobacterium bovis causing bovine tuberculosis outbreaks in Poland

Abstract

IntroductionSince 2009, Poland has been recognised as a country officially free of bovine tuberculosis (bTB), although in each year of the last five there were from 8 to 18 outbreaks of the disease. In 2008–2016, the largest number of cattle infected with bovine mycobacteria were eliminated in the Masovian Province (the central region of Poland) and the largest number of outbreaks of this zoonosis were recorded in this area. The close proximity of farms where bTB was found led to the suspicion that tuberculosis could have been transmitted between the affected herds. The aim of the study was the molecular characterisation of the pertinent M. bovis/caprae strains and determination of the epidemiological relationship of various bTB outbreaks.Material and MethodsThe material for microbiological tests came from 119 cattle (Bos taurus) from nine herds located in five provinces, neighbouring the Masovian Province.ResultsLaboratory tests of tissue material gave results confirming tuberculosis in 54 (45%) animals. All strains belonged to the Mycobacterium bovis species. A two-step analysis of genetic affinity allowed 50 strains to be identified as phylogenetically closely related and separated between three genetic clusters consisting of 2 to 27 strains.ConclusionBased on the results of genotyping, bTB outbreaks were found in three herds, and three transmission chains were identified among these herds.

Chronic tuberculosis caused by Mycobacterium bovis in a domestic donkey in Central Europe

“…This donkey, similarly to the previously described case, had no contact with cattle prior to developing the disease (Bryan et al., 2016). Poland is also recognised as a TB‐free country, but some outbreaks are reported each year (Krajewska‐Wędzina et al., 2020). The donkey lived in an area where the number of outbreaks was low and the distance from the last source of infection was over 100 km.…”

BCG and SARS-CoV-2—What Have We Learned?

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