Viral load dynamics in asymptomatic and symptomatic patients during Omicron BA.2 outbreak in Shanghai,China,2022:A longitudinal cohort study  

作　　者：Jingwen Ai Jiaxin Zhou Yang Li Feng Sun Shijia Ge Haocheng Zhang Yanpeng Wu Yan Wang Yilin Zhang Hongyu Wang Jianpeng Cai Xian Zhou Sen Wang Rong Li Zhen Feng Xiangyanyu Xu Xuemei Yan Yuchen Zhao Juanjuan Zhang Hongjie Yu Wenhong Zhang 

机构地区：[1]Department of Infectious Diseases,Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response,National Medical Center for Infectious Diseases,Huashan Hospital,Shanghai Medical College,Fudan University,Shanghai 200433,China [2]School of Public Health,Fudan University,Key Laboratory of Public Health Safety,Ministry of Education,Shanghai 200433,China [3]Shanghai Huashen Institute of Microbes and Infections,Shanghai 200050,China

出　　处：《Virologica Sinica》2024年第6期851-859,共9页中国病毒学(英文版)

基　　金：financial support from the Key Program of the National Natural Science Foundation of China(82130093);Wenhong Zhang,Juanjuan Zhang acknowledge financial support from Shanghai Municipal Science and Technology Major Project(HS2021SHZX001);Wenhong Zhang acknowledges financial support from the Key Program of the National Natural Science Foundation of China(82161138018 and 82041010);Shanghai Science and Technology Committee(20dz2260100,20Z11901100);Shanghai Hospital Development Center(SHDC2020 CR5010-002).

摘　　要：The SARS-CoV-2 virus,particularly the Omicron BA.2 variant,led to a significant surge in Shanghai,2022.However,the viral load dynamic in Omicron infections with varying clinical severities remain unclear.This prospective cohort included 48,830 hospitalized coronavirus disease 2019(COVID-19)patients across three hospitals in Shanghai,China,between 23 March and 15 May,2022.Systematic nucleic acid testing was performed using RT-PCR Cycle threshold(Ct)value as a proxy of viral load.We analyzed the kinetic characteristics of viral shedding by clinical severity and identified associated risk factors.The study comprised 31.06%asymptomatic cases,67.66%mild-moderate cases,1.00%severe cases,0.29%critical and fatal cases.Upon admission,57%of patients tested positive,with peak viral load observed at 4 days(median Ct value 27.5),followed by a decrease and an average viral shedding time(VST)of 6.1 days(Interquartile range,4.0–8.8 days).Although viral load exhibited variation by age and clinical severity,peak Ct values occurred at similar times.Unvaccinated status,age exceeding 60,and comorbidities including hypertension,renal issues kidney dialysis and kidney transplantation,neurological disorders,rheumatism,and psychotic conditions were found to correlate with elevated peak viral load and extended VST.Asymptomatic cases demonstrated a 40%likelihood of contagiousness within 6 days of detection,while mild-moderate and severe cases exhibited post-symptom resolution infectious probabilities of 27%and over 50%,respectively.These findings revealed that the initial Ct values serve as a predictive indicator of severe outcomes.Unvaccinated elderly individuals with particular comorbidities are at high-risk for elevated viral load and prolonged VST.

关 键 词：COVID-19 Omicron BA.2 Viral load dynamics Viral shedding time 

分 类 号：R373[医药卫生—病原生物学]