NATIONWIDE COMMUNITY SURVEY OF TUBERCULOSIS EPIDEMIOLOGY IN SAUDI-ARABIA

In the first nationwide community-based survey of the epidemiology of tuberculosis in Saudi Arabia, 7721 subjects were screened in the 5 pro vinces (using an equal proportional allocation formula) for 2 paramete rs: (1) prevalence of positive Mantoux test in non BCG vaccinated subj ects; (2) prevalence of bacillary cases on sputum culture. The prevale nce of positive Mantoux reaction in children aged 5-14 years was 6% +/ - 1.8; higher in urban areas (10%), and lower in rural areas (2%), thu s classifying Saudi Arabia among the middle prevalence countries. Thes e relatively good results (by Third World standards) could reflect the rise of the standard of living and wide availability of free treatmen t for active cases with a lowered risk of infection in the community. This view is supported by the fact that in our survey, only one subjec t grew Mycobacterium tuberculosis in the sputum. However, there were f oci of high prevalence of Mantoux reaction in the urban communities in the Western province (20% +/- 8.7 urban; 1% +/- 1.9 rural). The probl em may be caused by the fact that the province receives every year ove r a million pilgrims, some of whom are known to settle illegally and e scape the usual screening for tuberculosis imposed on foreign labourer s. In conclusion, even in the absence of an enforceable national progr amme for the eradication of tuberculosis, the economic standard and wi de availability of free treatment for active cases has resulted in rel atively low rates of prevalence of tuberculin sensitivity in children. The foci of high prevalence in the Western Province require special s creening arrangements.