Non-typeable Haemophilus influenzae chronic colonisation in Chronic Obstructive Pulmonary Disease (COPD)

Haemophilus influenzae is the most common cause of bacterial infection in the lungs of chronic obstructive pulmonary disease (COPD) patients and can lead to episodes of acute exacerbation resulting in increased hospitalisation and mortality. Although H. influenzae has developed multiple mechanisms to prolong its colonisation in the lower airways of COPD patients, a key reason for this persistence is the ability of H. influenzae to adhere to host epithelial cells in
order to form biofilms. The formation of biofilms is associated with changes in bacterial behaviour such as reduced cellular metabolism and production of an obstructive extracellular matrix (ECM). Herein we discuss the mechanisms by which H. influenzae adheres to host airway epithelial cells to induce the formation of biofilms, the role these biofilms play in the pathogenesis of COPD and the mechanisms by which these cellular aggregates promote
persistence in the lungs through immune system evasion and antibiotic tolerance.