Avoiding the effect of BCG-vaccination by detecting MTB-infection with a new blood test

Methods: We compared the TST with a Mycobacterium tuberculosis (MTB)-specific ELISPOT-assay during an outbreak Results: Participants were grouped according to their risk of LTBI in close (n=36) or occasional (n=333) contacts to the index case. For the TST the positive response rate was 53% (19/36) among close and 16% (52/333) among occasional contacts. Fifty-six TST-positive contacts (56/71=78.9%) and 27 TST-negative controls (27/298=9.1%) underwent ELISPOT testing. The OR of a positive test result across the two groups was 29.2 (95% CI 3.5–245.0) for the ELISPOT and 19.7 (95% CI 2.0–190.2) for the TST with a 5m…