Tuberculin Response in Infants after BCG Vaccination during Neonatal Stage

ABSTRACT

PURPOSE: Mantoux test was widely used to identify the tuberculosis. But no reliable method exists for distinguishing tuberculin reactions caused by previous BCG vaccination from those caused by mycobacterial infections. So we studied Mantoux response in infants who had received BCG vaccination in the first month of life. METHODS: Mantoux testing was carried out in 143 healthy infants aged from 3 to 15months who had received BCG vaccination in the first month of life. Among them, 81 received Japan 172 strain BCG vaccination with multiple puncture method and 62 Copenhagen 1331 strain with intradermal method. RESULTS: The mean Mantoux reactions in the Japan 172 strain group were as follows 10.0mm at 3 months, 9.7mm at 4-6months, 11.4mm at 7-9months, and 10.5mm at 10-15months. The mean Mantoux reactions in the Copenhagen 1331 strain group were as follows 7.6mm at 3 months, 7.5mm at 4-6months, 7.5mm at 7-9months, and 6.8mm at 10-15months. Infants who received Japan strain had significantly larger sized induration in all ages. About 50% of Japan strain BCG-vaccinated infants had more than 10mm of tuberculin reaction. CONCLUSION: Infants who received Japan strain had significantly larger sized tuberculin reaction in all ages. Although the size of induration is more than 10mm in Tokyo strain BCG-vaccinated child, vaccine effect should be generally considered.