Mask Sampling and the TB Aerosol: a new detection method and approach to transmission studies. (360G-Wellcome-107302_Z_15_Z)

Although Mycobacterium tuberculosis (Mtb) depends on aerosol transmission, the number of bacilli expectorated over time, diurnal variability and correlations with clinical features, are unknown. Infectivity assessed by sputum analysis provides a crude gradient of transmission risk but lacks predictive value. Cough Aerosol Sampling System (CASS) identifies transmission risk better than sputum analysis but do not directly capture infectious aerosols naturally. Mask sampling has potential as an am enable sampling system to aid understanding, management and ultimate control of TB and other airborne infections. Here, I will develop our established mask sampling approach to quantify Mtb aerosol output and characterise the production of Mtb, map diurnal patterns of aerosol production, determine relationships between Mtb in aerosols and concurrent sputum samples and the value of aerosol measurements as a marker of infectivity. I will optimise the sampling protocol and develop a standardised q uantitative molecular assay which will be applied to serial mask samples to assess the total daily aerosol output of Mtb, circadian variability and correlation with cough and clinical features. A comparison of the mask and CASS will provide reference to an established technique. Finally, I will use the TB Case Control Platform to relate mask results and transmission.