[Mycobacterial infections in man: bacteriological, clinical and epidemiological evaluation (author's transl)].

At present time the direct microscopy of acid-alcohol fast bacteria includes Mycobacteria, Nocardia, "rhodochrous complex". Direct microscopy is suitable to identify visible and not viable bacteria, the debacillization curve and the fall and rise phenomenon. Strains of M. tuberculosis complex are frequently with partial virulence low infectivity, and are modified by drugs. Little or no reaction to PPD is present.