COMPARATIVE SKIN TESTING WITH PPD TUBERCULIN, MYCOBACTERIUM-AVIUM ANDMYCOBACTERIUM-SCROFULACEUM SENSITIN IN SCHOOLCHILDREN IN SAUDI-ARABIA

Setting: Jizan region, Saudi Arabia. Objective: To test methodology fo r studies of tuberculin sensitivity and effectiveness of BCG vaccinati on programme. Design: School children (n = 315) aged 6-12 years simult aneously tested intradermally with PPD tuberculin RT23, 2TU and 0.1 mu g Mycobacterium avium or M. scrofulaceum sensitin. Presence of BCG sca r as evidence of previous BCG vaccination. Cervical lymph nodes palpat ed. Results: BCG coverage was 75%. The prevalences of positive reactio ns (induration greater-than-or-equal-to 6 mm) were higher among childr en with than without scar. Prevalences of positive reactions to PPD an d M. scrofulaceum sensitin were higher among girls than boys. In child ren with scar, the mean size of positive reactions to PPD was larger a mong girls than boys, and the prevalence of positive reactions was sma ller in this group among children with than without palpable cervical lymph nodes. The sizes of reactions both to M. avium and to M. scroful aceum sensitin were correlated to the size of the tuberculin reactions . Previous admission to hospital was reported less often by children w ith than without scar. Conclusions: The technique applied and training of staff was satisfactory. In further studies, however, we will apply three simultaneous tests to each person.