Fig 5. Clear differences in the pulmonary microbiota of Global Initiative for Chronic Obstructive Lung Disease (GOLD) 3 COPD patients compared to GOLD 2 COPD patients.

Mean Shannon and Simpson diversity indices values (A) of GOLD 2 (black circle) and GOLD 3 patients (black square) were measured during exacerbation. Mean genus proportions and qPCR values of clinically important pathogens were quantified (B) in the sputum of GOLD 2 (black circle) and GOLD 3 (black square) COPD patients. *: p≤0.05.