Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China;
Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China;
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.
The investigators used data from Huashan Hospital, Renji Hospital, and Shanghai Jing' an Central Hospital to collect information on SARS-CoV-2 primary infections with BA.2 during 1 March to 23 May 2022, and followed up for participants' reinfections with BA.5-lineages during 1 December 2022 to 14 January 2023. After matched 1:1 by age and gender with the reinfection cohort, data of primary infections with BA.5-sublineages were also collected. Reinfection cases were defined as having positive COVID-19 PCR or antigen test, at least 90 days after participants' first positive testing. Basic information, vaccination status, time interval between two infections, and clinical manifestations were collected.
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