In SA, notably in absence of a dominant pathogen, there is greater abundance of Rothia spp., previously detected in mild non-eosinophilic asthma33 and bronchiectasis, where abundance negatively correlated with IL-8, IL-1β, MMP-1, MMP-8 and MMP-9 in sputum34. This evidence concerns the gene MMP8 and bronchiectasis.