The nature of mycobacterial disease in south east England, 1977-84.

The nature and incidence of bacteriologically confirmed mycobacterial disease in south east England over the eight year period 1977-84 has been determined by a study of cultures received by the PHLS Regional Centre for Tuberculosis Bacteriology at Dulwich. The number of cases of tuberculosis in the ethnic European population has shown a decline, more so among males than females, but there has not been a significant decline in cases among ethnic Asians. Most tuberculosis is due to the classical human tubercle bacillus but cases due to the Asian human type, the bovine type (M. bovis), and the African types (M. africanum) also occur. The number of cases of disease due to 'atypical' mycobacteria has doubled over the eight year period, and these now account for about 5% of bacteriologically diagnosed mycobacterial disease in this region. The continuing role of reference facilities for the surveillance of tuberculosis and the diagnosis and management of the growing numbers of other mycobacterial infections is stressed.