Fig 1.

QFT assay and TST results of 70 HCW. QFT assay values were obtained after ex vivo stimulation with ESAT-6, CFP-10, and TB7.7 antigens, while TST values are the results of tuberculin stimulation. Participants were stratified into three distinct groups according to their QFT assay and TST results. The black lines represent the cutoff value of the commercially available QFT assay of 0.35 IU/ml and the TST of 10 mm, while the dotted line represents the threshold value of a subpositive QFT assay response (i.e., 0.1 IU/ml).