Natural Reservoir, Zoonotic Tuberculosis & Interface with Human Tuberculosis: An Unsolved Question (Commentary) (Clinical Report‪)‬

Mycobacterium bovis is an important member of the M. tuberculosis complex. Although it is primarily recognized as an animal pathogen it can cause disease in humans too. Similarly, M. tuberculosis, though a human pathogen does infect animals. It is believed that as the human civilization has advanced through various stages of evolution it has acquired many diseases along side with the fruits of progress. For instance, it has been suggested that many diseases could not have existed in humans prior to the development of agriculture (1). The hypothesis is that farming led to enhanced availability of food which in turn increased population size favourable for maintenance of infectious pathogens in the population. Such pathogens though virulent possibly could not have persisted in small, pre-agricultural population. This argument led to the traditional view of the connection between farming, disease and humans that the pathogens were derived from domestic animals. Me Neill wrote, "Most and probably all of the distinctive infectious diseases of civilization transferred to human populations from animal herds. Contacts were closest with the domesticated species, so it is not surprising to find that many of our common infectious diseases have recognizable affinities with one or another disease afflicting domesticated animals" (2). Many of the fatal civilizational diseases such as measles, tuberculosis, small pox, influenza, pertussis and falciparum malaria, are believed to have arisen this way (3).