Review on Epidemiological Features of Mycobaterium Bovis at the Human, Cattle and Wildlife Interface in Ethiopia

Mycobaterium bovis is among a pathogenic species which belongs to the Mycobacterium tuberculosis complex (MTBC), a group of genetically closely related mycobacteria [1]. Mycobaterium bovis (M. bovis) is an intracellular, non-motile, facultative, weakly Gram-positive acid-fast bacillus [2]. The MTBC sub-group also comprises M. tuberculosis, M. africanum, M. canettii, M. pinnipedii, M. microti and M. caprae that are generally regarded as host adapted but with the ability to spill over into other species. Mycobaterium bovis is the primary cause of bovine tuberculosis (BTB). M. tuberculosis, M. africanum, M. caprae and M. canettii are human pathogens. M. caprae which causes infection in goats has been initially classified as subspecies of M. bovis but was recently recognized as a species on its own. M. microti affects rodents and M. pinnipedii have been isolated from seals [2]. Mycobaterium bovis has an exceptionally wide range of mammalian hosts and affects all age groups of susceptible hosts of domestic, wild animals and human [2]. Cattle are the most common maintenance host for M. bovis infection from which transmission can occur to wildlife, or people animals [3]. Opossums, badgers and bison are known maintenance hosts in different European countries and African buffalo, Kudu, deer, lechwe and wild boar have been classified as maintenance hosts for M. bovis in Africa [4]. Many susceptible animals and wildlife species, including man are spillover hosts in which infection is not selfmaintaining [5]. Bovine tuberculosis is one of the chronic bacterial diseases of animals that can take a variable amount of time (from a few weeks to a life time) to develop from infection to clinical disease and to become infectious to other animals [2,6]. The disease mostly affects cattle and rarely other species of domestic animals [7]. The name “Tuberculosis” comes from the nodules, called‘tubercles’, which form in the lymph nodes of affected animals and the disease is characterized by the progressive development of specific granulomatous lesions of tubercles in affected tissues and organs [2].