Clinical and epidemiological differences and similarities of viral pneumonias in two pandemics

Background: In a decade, we faced two pandemic viruses, influenza A H1N1pdm09 and SARS CoV-2, whose most serious manifestation is pneumonia. Aim: To compare the clinical, epidemiological and management aspects of pneumonias caused by each pandemic virus in adults requiring hospitalization. Material and methods: Comparative, observational study carried out at a regional Chilean hospital, including 75 patients with influenza A H1N1pdm09 prospectively studied in 2009 and 142 patients with SARS CoV-2 studied in 2020.