Using a tuberculosis (TB) household contact (HHC) study design among 130 Ugandan children less than 5 years of age with Mtb exposure, this study was conducted to determine the following: (1) the prevalence of Mtb immune sensitization in young children heavily exposed to TB using both the tuberculin skin test (TST) and QuantiFERON Gold Plus (QFT-Plus) interferon gamma release assay, and to examine the concordance of these two tests; and (2) the diagnostic accuracy of TST and QFT-plus for confirmed and unconfirmed TB in young children. Here, IFNG is linked to tuberculosis.