Tuberculosis in commerce and industry in a Western Cape suburb, South Africa, 1987

A postal questionnaire of 557 industries in a defined area of the Western Cape, South Africa, aimed to determine the incidence of pulmonary tuberculosis (TB) in 1987 as well as the provision of health services. A 65% response rate was obtained. A random sample of non-respondents did not differ from respondents with respect to factory size or sector. The overall incidence rate for 1987 was 472 per 100,000 workers (95% confidence interval 386-558). Tuberculosis rates of Africans and "coloureds" were substantially higher than those of Asians and whites. There was considerable variation in the rates by employment sector. We found highest rates of TB in the textile and iron and steel industries and the lowest rates are reported among the printing and paper industry, in trade and commerce, and in the transport sectors. It is likely that the differences in the rates by sector reflect the different social class composition of their work force. TB incidence rates also varied by factory size, with the highest rates being reported in the smallest factories. The implications of the study are that the current policy of not screening workers in industry on a routine basis for TB needs to be urgently reviewed. The provision of health services, shown to vary according to factory size, was found to be inadequate in the smaller factories. Alternative methods of providing such care to workers need to be implemented.