The optimum sensitivity of 77.2% and specificity of 87.2% of the IL-2/IFN-γ ratio in detecting ATB from LTBI (cut-off value of 1.133) suggested that this ratio may not function as a stand-alone diagnostic indicator of LTBI, but one of the valid methods to distinguish active TB from latent infection. Here, IL2 is linked to disease arising from reactivation of latent virus.