Is tuberculin testing before BCG vaccination necessary for children over three months of age?

In July 2007 Irish national policy changed such that children aged 3 months to 6 years no longer routinely require tuberculin (Mantoux) skin testing prior to BCG vaccination. Previous to that a tuberculin test was required in all children in this age group pre vaccination. While the previous policy was in place this study was conducted to assess the value of this test. The observation that children are frightened by the test (an injection into the skin) prompted the study. The author conducted a retrospective study of the results of 1,854 tuberculin tests performed as a prerequisite to BCG vaccination and found that only 0.7% of children had a positive test result (induration > 5mm). None of 107 children < 6 years of age tested positive. Those > 12 years were more likely to test positive than younger children (1.09% vs 0.4% respectively, p < 0.05). This study suggests that testing young children before BCG vaccination has a low yield of positive results and adds little to the detection of latent or active TB.