Non-tuberculosis mycobacteria in Africa. 2. Sensitivity to mycobacteriophages.

In this-the second of a series of studies on the prevalence of non-tuberculosis mycobacteria in Africa-the susceptibility of 228 cultures of non-tuberculosis mycobacteria isolated at tuberculosis laboratories in Nairobi, Kenya, and Lagos, Nigeria, to 7 laboratory strains of mycobacteriophages was examined. Of the 51 cultures found to be phage-sensitive, just over half (29) were saprophytic. In the cultures from East Africa, phage-sensitive strains were observed only among the saprophytes, whereas in those from West Africa such strains occurred also among unpigmented mycobacteria (Runyon's Group III). All but one strain of non-tuberculosis mycobacteria isolated from domestic animals in East Africa were found to be resistant to all 7 phages used. Unfortunately, the patterns of phage sensitivity showed such variety that it was concluded that phage-typing alone was unsuitable for the classification of non-tuberculosis mycobacteria.