Bacterial coinfections contribute to severe COVID-19 in winter

Dear Editor, Although most cases of COVID-19 caused by SARS-CoV-2 Omicron variants are mild or asymptomatic worldwide,coinfec-tion with SARS-CoV-2 and other respiratory pathogens may still aggravate the severity of the illness.1,2 The current literature indicates that coinfection with COVID-19 could occur in 3.70％-9.7％of patients.1,3,4 The proportion of bacterial,and other respiratory viral coinfections may range from 3.02％to 9.7％and 5.41％to 6.61％,respectively.However,these studies demon-strated that coinfections with respiratory pathogens are not common.Thus,antibacterial therapy and diagnostic tests are considered to be unnecessary upon admission for most patients hospitalized with COVID-19.