The QFT, IP-10 and IL-2 tests rendered similar positive rates in the HC group with low risk of Mtb exposure (17.1%, 18.4% and 14.5%, respectively), which suggested that those antigen-stimulated positives in health controls could result from LTBI rather than false positive responders, as the investigated population from an area with high prevalence of TB [29], [30]. This evidence concerns the gene CXCL10 and tuberculosis.