Recent experience in the epidemiology of disease caused by atypical mycobacteria.

To obtain information on the epidemiology of mycobacteriosis, water and air samples collected along the East Coast of the United States were examined for mycobacteria. Mycobacterium avium-intracellulare-scrofulaceum (MAIS) were isolated from 25% of the water, samples, mostly those from South Carolina, Georgia, and the Gulf states. Mycobacterium kansasii and Mycobacterium marinum were not found, probably because of the detrimental effects of the NaOH used to decontaminate the samples. MAIS strains were found more often in estuaries than in fresh or ocean waters. The frequency of Mycobacterium intracellulare was relatively uniform along the entire coast, while Mycobacterium scrofulaceum predominated in the South. Only M. intracellulare was found in aerosol specimens, although both M. intracellulare and M. scrofulaceum were found in waters collected at the same sites.