Table 3

Samples with positive qPCR signals obtained from mask and sputum samples

Target/samplePatients with COPD (9/13)*HV (3/10)*
Paired mask-ae (copies/mask) and sputum (sp) samplesMask onlyMask only
mefA ae 114151445 159872435742541204785923163181829
sp 6727162728625374 722
tetM ae 10133472963651362258<308247134<290
sp 45 295<37 82848†40 590
ErmB ae <<<<1375239<1379273<<1470
sp <<<<17 352<<<
blaTEM ae <<<<<<<<365<<<
sp <<<<<
Ratio mefA/ ae
tetM sp 0.150.0256.71.84
Pathogen qPCRNilMc+PaNilHiNilNilNilNilNil
  • –, not done; <, below limit of detection (100 copies). Note: pt 11-prophylactic amoxicillin-antimicrobial resistance (AMR) genes below limit of detection.

  • *Figures in parentheses show number of subjects positive/total number of subjects sampled.

  • †>100 copies detected.

  • ae, mask aerosol sample (copies per mask); Amox, amoxicillin; COPD, chronic obstructive pulmonary disease; Co-Amox, co-amoxiclav; HV, healthy volunteers; Hi, Haemophilus influenzae; Mc, Moraxella catarrhalis; Pa, Pseudomonas aeruginosa; Proph/SM, prophylaxis/self-management; sp, sputum (copies per gram).Tet, tetracycline; qPCR, quantitative PCR;