A prognostic method for determining the risk of a human subject with asymptomatic tuberculosis infection or suspected TB infection progressing to active TB disease, comprising the steps of: (a) providing a sample from a human subject with asymptomatic TB infection or suspected TB infection; (b) quantifying and computationally analysing relative abundances of a collection of pairs of gene products (TB biomarkers), selected from a 6 gene signature consisting of PCR-amplified gene products using 6 gene specific primers, forming 9 amplified products of the following 6 genes: GBP2; FCGR1B; SERPING1; TUBGCP6; TRMT2A; SDR39U1 (PCR 6-gene model) for the detection of the following TB biomarkers: i) GBP2.and TUBGCP6, ii) GBP2. and TRMT2A, iii) GBP2. and SDR39U1, iv) FCGR1B. and TUBGCP6, v) FCGR1B. and TRMT2A, vi) FCGR1B. and SDR39U1, vii) SERPING1. and TUBGCP6, Viii) SERPING1. and TRMT2A and ix) SERPING and SDR39U1, wherein the computational analysis comprises the steps of: (i) mathematically associating a coefficient with each of the quantified relative abundances of step (b) to compute a numerical "progressor" or "control" score and wherein the "progressor" or "control" score is determined using a pair ratio-based mathematical approach whereby: Score = "progressor" if: R1 - R2 + d > 0 Score = "control" if: R1 - R2 + d ≤ 0, wherein R1 and R2 represent log-transformed raw abundances of two gene products in the pair and coefficient "d" is as set out as follows: GBP2.and TUBGCP6and coefficient d: -2,3 GBP2 and TRMT2A and coefficient d: -5,7 GBP2 and SDR39U1 and coefficient d: -4,7 FCGR1Band TUBGCP6 and coefficient d: 2,4 FCGR1B and TRMT2A and coefficient d: -1,2 FCGR1B and SDR39U1and coefficient d: -0,2 SERPING1 and TUBGCP6 and coefficient d: 0,7 SERPING1 and TRMT2A. and coefficient d: -2,5 SERPING1 and SDR39U1and coefficient d: -1,5; (ii) tallying the "progressor" or "control" scores from all of the pairs of gene products to obtain an overall percentage vote for "progressor" or "control"; and (iii) predicting the risk of progression to TB disease based on the overall "progressor" or "control" vote obtained from step (ii) above, wherein an overall vote of "progressor" indicates that a subject with asymptomatic TB infection or suspended TB infection is likely to progress to active TB disease. (a) providing a sample from a human subject with asymptomatic TB infection or suspected TB infection; (b) quantifying and computationally analysing relative abundances of a collection of pairs of gene products (TB biomarkers), selected from a 6 gene signature consisting of PCR-amplified gene products using 6 gene specific primers, forming 9 amplified products of the following 6 genes: GBP2; FCGR1B; SERPING1; TUBGCP6; TRMT2A; SDR39U1 (PCR 6-gene model) for the detection of the following TB biomarkers: i) GBP2.and TUBGCP6, ii) GBP2. and TRMT2A, iii) GBP2. and SDR39U1, iv) FCGR1B. and TUBGCP6, v) FCGR1B. and TRMT2A, vi) FCGR1B. and SDR39U1, vii) SERPING1. and TUBGCP6, Viii) SERPING1. and TRMT2A and ix) SERPING and SDR39U1, i) GBP2.and TUBGCP6, ii) GBP2. and TRMT2A, iii) GBP2. and SDR39U1, iv) FCGR1B. and TUBGCP6, v) FCGR1B. and TRMT2A, vi) FCGR1B. and SDR39U1, vii) SERPING1. and TUBGCP6, Viii) SERPING1. and TRMT2A and ix) SERPING and SDR39U1, (i) mathematically associating a coefficient with each of the quantified relative abundances of step (b) to compute a numerical "progressor" or "control" score and wherein the "progressor" or "control" score is determined using a pair ratio-based mathematical approach whereby: Score = "progressor" if: R1 - R2 + d > 0 Score = "control" if: R1 - R2 + d ≤ 0, wherein R1 and R2 represent log-transformed raw abundances of two gene products in the pair and coefficient "d" is as set out as follows: GBP2.and TUBGCP6and coefficient d: -2,3 GBP2 and TRMT2A and coefficient d: -5,7 GBP2 and SDR39U1 and coefficient d: -4,7 FCGR1Band TUBGCP6 and coefficient d: 2,4 FCGR1B and TRMT2A and coefficient d: -1,2 FCGR1B and SDR39U1and coefficient d: -0,2 SERPING1 and TUBGCP6 and coefficient d: 0,7 SERPING1 and TRMT2A. and coefficient d: -2,5 SERPING1 and SDR39U1and coefficient d: -1,5; Score = "progressor" if: R1 - R2 + d > 0 Score = "control" if: R1 - R2 + d ≤ 0, GBP2.and TUBGCP6and coefficient d: -2,3 GBP2 and TRMT2A and coefficient d: -5,7 GBP2 and SDR39U1 and coefficient d: -4,7 FCGR1Band TUBGCP6 and coefficient d: 2,4 FCGR1B and TRMT2A and coefficient d: -1,2 FCGR1B and SDR39U1and coefficient d: -0,2 SERPING1 and TUBGCP6 and coefficient d: 0,7 SERPING1 and TRMT2A. and coefficient d: -2,5 SERPING1 and SDR39U1and coefficient d: -1,5; (ii) tallying the "progressor" or "control" scores from all of the pairs of gene products to obtain an overall percentage vote for "progressor" or "control"; and (iii) predicting the risk of progression to TB disease based on the overall "progressor" or "control" vote obtained from step (ii) above, wherein an overall vote of "progressor" indicates that a subject with asymptomatic TB infection or suspended TB infection is likely to progress to active TB disease.