Whispers in the Wind: Face Mask Sampling for Mycobacterium tuberculosis Detection in Children With Pulmonary Tuberculosis

Background Recently, face mask sampling (FMS) confirmed detection of Mycobacterium tuberculosis DNA from exhaled breath in adults with tuberculosis. To date, no study has evaluated the use of FMS to detect pulmonary tuberculosis in children. We developed a method for FMS of M. tuberculosis-specific DNA in children and performed a clinical exploration to assess feasibility in children.Methods Face masks were spiked, analyzed on GeneXpert-Ultra, quantitative polymerase chain reaction, and targeted next-generation sequencing. Children with pulmonary tuberculosis were asked to wear 3 modified FFP2 masks for 30 minutes as part of an exploratory clinical study.Results Experiments with H37Ra M. tuberculosis strain showed a limit of 95% detection of 3.75 colony-forming units (95% confidence interval, 4.85-3.11) on GeneXpert-Ultra. Ten children with pulmonary tuberculosis participated in the clinical study. M. tuberculosis-specific DNA was detected on none of the face masks.Conclusions Pediatric FMS has a low limit of detection for M. tuberculosis-specific DNA in vitro. However, M. tuberculosis DNA was not detected in any of 30 masks worn by children with pulmonary tuberculosis. This suggests that FMS in this form may not be more effective for detecting M. tuberculosis in children with tuberculosis than existing methods. We report the first use of face mask sampling for M. tuberculosis detection in children. In vitro experiments showed a limit of 95% detection of 3.75 CFU. However, M. tuberculosis DNA was not detected from 30 mask worn by 10 children with tuberculosis.