Characteristics of SARS-CoV-2 Reinfection

As the COVID-19 pandemic continues and the number of individuals with previous infection rises, numbers of SARS-CoV-2 reinfection are increasing. The second Omicron wave in Shanghai, China caused by BA.5-sublineages led to a large fraction of reinfections among BA.2 primary infections. To better understand the SARS-CoV-2 reinfection rate and clinical severity of reinfections, the investigators conducted a multi-centre cohort study. The investigators hope to provide valuable clinical evidences for reinfections and offer guidance for future policy making.

Inclusion Criteria:All PCR- or RAT-confirmed SARS-CoV-2 reinfections were included in the study.Exclusion Criteria:Patients who did not know if they were reinfected were excluded.