The genus Mycobacterium consists of a diverse group of organisms that are ubiquitous and are believed to be some of the oldest bacteria on earth. They may exist as free-living commensals inhabiting soil and water, but they are also potentially pathogenic to man and other animals, being transmitted by airborne or droplet spread. At least 25 species of mycobacteria have been associated with human disease. Robert Koch in 1882, identified the acid-fast bacterium (AFB), Mycobacterium tuberculosis as the causative agent of tuberculosis (TB). TB is an ancient disease that remains a significant global health problem With improved living standards and the introduction of chemotherapy in 195Os, the incidence of TB in most industrialized countries showed a progressive decline, with very little mortality by the mid 1980s. This pattern has changed over the last decade