Risk of reinfection and severity with the predominant BA.5 Omicron subvariant China, from December 2022 to January 2023
Jianpeng Cai, H. C. Zhang, Kun Zhu, Feng Zhu, Yan Wang, Sen Wang, Faren Xie, Meng Zhang, Lili Rui, Shuhong Li, Ke Lin, Quanlin Xue, Guanmin Yuan, Hongyu Wang, Yi Zhang, Yi Zhang, Zhangfan Fu, Jieyu Song, Yanliang Zhang, Yanliang Zhang, Jingwen Ai, Wenhong Zhang
Abstract
Data on reinfection in large Asian populations are limited. In this study, we aimd to evaluate the reinfections rate, disease severity and time interval between the infections in the symptomatic and asymptomatic population who are firstly infected with BA.2 Omicron Variant. We retrospectively included adult patients with COVID-19 discharged from four designated hospitals between April 27, 2021, and November 30, 2022, who were interviewed via telephone from January 29 to March 1, 2023. Univariable and multivariable analysis were used to explore risk factors associated with reinfection. A total of 16,558 patients were followed up, during the telephone survey of average 310.0 days, 1610 (9.72%) participants self-reported reinfection. The mean time range of reinfection was 257.9 days. Risk for reinfection were analyzed using multivariable logistic regression. Patients with severe first infection were at higher risk for reinfection (aORs, 2.50; P < 0.001). The male (aORs,0.82; P < 0.001), the elderly (aORs, 0.44; P < 0.001) and patients with fully vaccination (aORs, 0.67; P < 0.001) or booster (aORs, 0.63; P < 0.001) had the lower risk of reinfection. Patients over 60 years of age (aORs,9.02; P = 0.006) and in those with ≥2 comorbidities (aORs,11.51; P = 0.016). were at higher risk for severe reinfection. The number of clinical manifestations of reinfection increases in people with severe first infection (aORs, 2.82; P = 0.023). The overall reinfection rate was 9.72%, and the reinfection rate of Omicron-to-Omicron subvariants was 9.50% at one year. The severity of Omicron-Omicron reinfection decreased. Data from our clinical study may provide the clinical evidence and bolster response preparedness for future COVID-19 reinfection wave.