We propose that the ability of P. aeruginosa to chronically infect the lungs of patients with CF, pneumonia, COPD, and bronchiectasis is due in part to the secretion of OMV containing Cif, which inhibits CFTR mediated chloride secretion and thus, reduces the mucociliary clearance of pathogens. The gene discussed is CFTR; the disease is chronic obstructive pulmonary disease.