What is acid-fast bacilli ?

Mycobactera: It refers to a type of stain used to a identify bacteria, and means the bacteria hold on to the stain and appear red under the microscope. The most common acid fast bacilli. (AFB) are mycobacterium, of which the most famous is m. Tuberculosis. There are also non-tuberculous mycobacteria, and non-mycobacterial acid fast organisms that aren't bacilli (rod shaped organisms.).