Fig. 1.

Patient selection flowchart. PMH: past medical history, DM: diabetes. Hospitalized influenza patient demographics pre (2018 and 2019) and post (2020 to Feb 2021) pandemic were similar and were thus combined. Note that there were more hospitalized (n = 8216) than non-hospitalized COVID-19 patients (n = 2998) in our cohort because the exclusion/inclusion criteria used to confirm no history of preDM and DM and many non-hospitalized patients did not have these detailed data and thus excluded.