Other strains of TB

There is not only one strain that can cause TB, instead there are many. The M. tuberculosis complex includes 3 other mycobacteria which can cause tuberculosis. They are M. bovis, M. africanum and M. microti. The first two types are very rare and cause TB usually to only immunocompromised people, and M. microti is not usually pathogenic. But in some cases it can cause minor infections.