Factors associated with prolonged viral shedding of SARS-CoV-2 Omicron variant infection in Shanghai: A multicenter, retrospective, observational study

Shanghai has faced an unprecedented COVID-19 pandemic with the BA.2.2 strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron infection. Comprehensive insights into its epidemiology, clinical manifestations, and viral shedding dynamics are currently limited. This study encompasses 208373 COVID-19 patients that were infected with the Omicron BA.2.2 sub-lineage in Shanghai, China. Demographic information, clinical symptoms, vaccination status, isolation status, as well as viral shedding time (VST) were recorded. Among the COVID-19 patients included in this study, 187124 were asymptomatic and 21249 exhibited mild symptoms. The median VST was 8.3 days. The common clinical symptoms included fever, persistent cough, phlegm, sore throat, and gastrointestinal symptoms. Factors such as advanced age, presence of comorbidities, mild symptomatology, and delayed isolation correlated with extended VST. Conversely, female gender and administration of two or three vaccine doses correlated with a reduction in VST. This investigation offers an in-depth characterization and analytical perspective on Shanghai's recent COVID-19 surge. Prolonged viral shedding of SARS-CoV-2 was observed in elderly, male, symptomatic patients, and those with comorbidity. Female, individuals with two or three vaccine doses, as well as those isolated early, shows an effective reduced VST.