Abstract

The aim of this study was to evaluate the effect of Bacille Calmette Guérin vaccination after long time on tuberculin skin test in adults, because the long-term effect of BCG vaccination is not known in Iran. We carried out a cross-sectional study on 464 on-duty soldiers in a systematic random selection in 2008. Purified protein derivative was injected intradermally with quantity 0.1 mL into the fore arm and induration size of skin test was measured after 48-72 h. Induration more than 10 mm was taken as positive reaction. In here all soldiers were man with mean age of 23.28±1 years. All of them had Bacille Calmette Guérin scar in their arms and about 31 (6.7) had positive tuberculin skin test and 8 (1.7) of them had positive test size 20-30 mm. One subject had sub-clinical pulmonary tuberculosis. We conclude, that adult with the history of Bacille Calmette Guérin vaccination in their neonatal age that had positive tuberculin skin test should be considered as new tuberculosis infection.