Bacteria: Mycobacterium bovis

Abstract

Tuberculosis (TB) is an important human and animal disease worldwide in terms of adverse health effects and economic loss. Bovine tuberculosis (bTB), caused by Mycobacterium bovis (MB), a member of the Mycobacterium tuberculosis complex, is an important cause of disease affecting humans, cattle, and other ruminants. MB is more prevalent and has the widest host range than other TB bacteria. The symptoms of human disease due to MB are similar to those of disease caused by M. tuberculosis (MT), although MB is more likely to cause extrapulmonary disease as well as infecting the lungs. In clinical practice, MB can only be differentiated from MT using biochemical or genetic tests. Transmission to humans generally occurs after close contact with infected animals or consumption of unpasteurized contaminated dairy products. Investigations are needed to elucidate the relative importance of MB as regards TB incidence in humans, especially in developing countries. Standard public health measures used to manage patients with contagious MT should be applied to contagious patients with MB to stop person-to-person spread. Also, measures should be developed to identify and control MB infection in wild animals, as these animals may be important reservoirs of infection for domesticated food-producing animals.