M. avium

Mycobacterium avium complex is a group of mycobacteria comprising Mycobacterium intracellulare, Mycobacterium avium, and Mycobacterium chimaera that are commonly grouped together because they infect humans together. This infection causes respiratory illness in birds, pigs, and humans, especially in immunocompromised people. In the later stages of AIDS it can be very severe. It usually first presents as a persistent cough. It is typically treated with a series of three antibiotics for a period of at least six months. M. avium, M. intracellulare, and M. chimaera are each saprotrophic organisms present in soil and water. Entry into hosts is usually via the gastrointestinal tract, but also can be via the lungs. Postinfection treatment involves a combination of antituberculosis antibiotics, including rifampicin, rifabutin, ciprofloxacin, amikacin, ethambutol, streptomycin, clarithromycin or azithromycin.