Bovine tuberculosis infection in animal and human populations in Ethiopia: a review

Ethiopia is one among the nations that possesses the largest number of livestock population in the African continent estimated to be 33 million cattle, 24 million sheep and 18 million goats. In contrast to the huge livestock resource, the livestock productivity is however, found to be very low. The major biological and socioeconomical factors attributing to the low productivity includes: the low genetic potential and performance, poor nutrition (in quality and quantity terms), the prevailing of different diseases, traditional way of husbandry systems and inadequate skilled manpower, among others. Ethiopia is one of the African countries where tuberculosis is wide spread in both humans and cattle and the endemic nature of tuberculosis in humans and cattle has long been documented. The disease is considered as one of the major livestock diseases that results in high morbidity and mortality, although the current status on the actual prevalence rate of bovine tuberculosis (BTB) at a national level is yet unknown. Detection of BTB in Ethiopia is carried out most commonly on the basis of tuberculin skin testing, abattoir meat inspection and very rarely on bacteriological techniques. Recently undertaken studies indicated the prevalence rate of BTB with a range of 3.4% (in small holder production system) to 50% (in intensive dairy productions) and a range of 3.5% to 5.2% in slaughterhouses in various places of the country. BTB in cattle remains to be a great concern due to the susceptibility of humans to the disease. The infections mainly take place by drinking raw milk and occur in the extra-pulmonary form, in the cervical lymphadenitis form in particular. The aim of this paper is to review the status of BTB in Ethiopia in relation with the existing animal husbandry systems and abattoir meat inspection surveillances. Control measures, economic impacts and the zoonotic aspect of the disease are also briefly addressed.