Epidemiology, pathophysiology, and microbiology of communityacquired pneumonia
Despite improvements in the clinical management of patients with community-acquired pneumonia (CAP) over the last decade, the incidence of the condition remains high, especially in Europe. Globally, pneumonia continues to be associated with high morbidity, mortality, and health costs. Moreover, its management poses many challenges. The microbial identification of pathogens remains difficult even though new molecular tests have been developed, mainly because of the difficulties interpreting the results. Also, the epidemiological changes due to serotype replacement after introducing the pneumococcal conjugate vaccine represent an emerging issue. Whereas the lungs were once thought to be sterile, it is now known that there is a respiratory microbiome with a dynamic microbiological ecosystem. However, this is a relatively unknown field. This review article provides an overview of our current understanding of the epidemiology, physiopathology, and microbial etiology of pneumonia.