Respiratory tract barrier dysfunction in viral-bacterial co-infection cases

Protective Effects from Prior Pneumococcal Vaccination in Patients with Chronic Airway Diseases during Hospitalization for Influenza—A Territory-Wide Study

“…Pneumonia is a common complication of influenza, which can be due to primary influenza pneumonia, secondary bacterial pneumonia, and mixed viral and bacterial pneumonia [3]. Secondary bacterial pneumonia was differentiated from mixed viral and bacterial pneumonia by the chronological sequence of the infections, whether it was a preceding or concurrent viral respiratory tract infection [4]. The incidence of secondary bacterial pneumonia is reported to be five times higher among older individuals and those with underlying co-morbidities [5], with the onset within the first six days of influenza infection [6].…”

“…In patients with chronic obstructive pulmonary disease (COPD), Gram-negative bacteria such as Enterobacteriaceae and Pseudomonas aeruginosa (P. aeruginosa) are also frequently isolated in COPD exacerbation and pneumonia [8]. Respiratory viral-bacterial co-infection has been reported to be associated with increased mortality and morbidity as compared to a viral or bacterial infection alone in elderly and chronically ill patients [4,9].…”