Mycobacterium bovis infection in human beings

The causative agent of bovine tuberculosis, Mycobacterium bovis, is also responsible for some cases of tuberculosis in human beings. Although recognized for over a century, this form of human tuberculosis has been a source of considerable misunderstanding and controversy. Questions still remain concerning the relative virulence of M. tuberculosis and M. bovis in human beings, the risk of human disease after infection, the immunological consequences of infection that does not proceed to disease, the occurrence of human-to-human transmission of M. bovis and the health risk of diseased human beings to cattle. The advent of the HIV/AIDS pandemic raises new questions of the epidemiological impact of immunosuppression on the transmission of M. bovis to and between human beings. Although largely eradicated in the developed nations, bovine tuberculosis still occurs in many developing nations and epidemiological data on the impact of this on human health is scanty but, in the light of the increasing incidence of tuberculosis worldwide, it is urgently needed.