Survival of mycobacterial species in aerosols generated from artificial saliva.

Tuberculosis is transmitted primarily by the aerosol route and the aim of this study was to measure the ability of pathogenic mycobacteria to survive in aerosols generated from artificial saliva. Aerosols of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium tuberculosis were generated and maintained in air under controlled conditions using a Henderson apparatus and a rotating drum. There were no differences in aerosol survival between the three species, and all had a poor survival rate over a period of 1 h. These data confirm epidemiological studies that close and prolonged contact with a TB patient is required for transmission of infection.