Zhang Ci, Zhou Chao, Xu Wanqing, Zheng Shimin, Gao Yanxiao, Li Peiqi, Deng Luojia, Zhang Xuezhixing, Jiang Qianxue, Qian Frank, Li Xianhong, Wang Honghong, Zou Huachun, Xia Yinglin, Wang Tao, Lu Hui, Qian Han-Zhu
Xiangya School of Nursing, Central South University, Changsha, China.
Xiangya Center for Evidence-Based Nursing Practice & Healthcare Innovation (A JBI Affiliated Group), Changsha, Hunan Province, China.
Infect Med (Beijing). 2023 Mar;2(1):11-18. doi: 10.1016/j.imj.2022.12.001. Epub 2022 Dec 17.
Global evidence on the transmission of asymptomatic SARS-CoV-2 infection needs to be synthesized.
A search of 4 electronic databases (PubMed, EMBASE, Cochrane Library, and Web of Science databases) as of January 24, 2021 was performed. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Studies which reported the transmission rate among close contacts with asymptomatic SARS-CoV-2 cases were included, and transmission activities occurred were considered. The transmission rates were pooled by zero-inflated beta distribution. The risk ratios (RRs) were calculated using random-effects models.
Of 4923 records retrieved and reviewed, 15 studies including 3917 close contacts with asymptomatic indexes were eligible. The pooled transmission rates were 1.79 per 100 person-days (or 1.79%, 95% confidence interval [CI] 0.41%-3.16%) by asymptomatic index, which is significantly lower than by presymptomatic (5.02%, 95% CI 2.37%-7.66%; <0.001), and by symptomatic (5.27%, 95% CI 2.40%-8.15%; <0.001). Subgroup analyses showed that the household transmission rate of asymptomatic index was (4.22%, 95% CI 0.91%-7.52%), four times significantly higher than non-household transmission (1.03%, 95% CI 0.73%-1.33%; =0.03), and the asymptomatic transmission rate in China (1.82%, 95% CI 0.11%-3.53%) was lower than in other countries (2.22%, 95% CI 0.67%-3.77%; =0.01).
People with asymptomatic SARS-CoV-2 infection are at risk of transmitting the virus to their close contacts, particularly in household settings. The transmission potential of asymptomatic infection is lower than symptomatic and presymptomatic infections. This meta-analysis provides evidence for predicting the epidemic trend and promulgating vaccination and other control measures. Registered with PROSPERO International Prospective Register of Systematic Reviews, CRD42021269446; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=269446.
需要综合全球关于无症状严重急性呼吸综合征冠状病毒2（SARS-CoV-2）感染传播的证据。
截至2021年1月24日，对4个电子数据库（PubMed、EMBASE、Cochrane图书馆和Web of Science数据库）进行了检索。遵循系统评价和Meta分析的首选报告项目（PRISMA）指南。纳入报告无症状SARS-CoV-2病例密切接触者传播率的研究，并考虑发生的传播活动。传播率采用零膨胀贝塔分布进行汇总。风险比（RRs）使用随机效应模型计算。
在检索和审查的4923条记录中，15项研究符合条件，包括3917名与无症状感染者的密切接触者。无症状感染者的汇总传播率为每100人日1.79例（或1.79%，95%置信区间[CI]0.41%-3.16%），显著低于症状前感染者（5.02%，95%CI 2.37%-7.66%；<0.001）和有症状感染者（5.27%，95%CI 2.40%-8.15%；<0.001）。亚组分析显示，无症状感染者的家庭传播率为（4.22%，95%CI 0.91%-7.52%），比非家庭传播率（1.03%，95%CI 0.73%-1.33%；P=0.03）高4倍，中国的无症状传播率（1.82%，95%CI 0.11%-3.53%）低于其他国家（2.22%，95%CI 0.67%-3.77%；P=0.01）。
无症状SARS-CoV-2感染者有将病毒传播给其密切接触者的风险，尤其是在家庭环境中。无症状感染的传播潜力低于有症状和症状前感染。这项Meta分析为预测疫情趋势以及颁布疫苗接种和其他控制措施提供了证据。在国际系统评价前瞻性注册库PROSPERO注册，CRD42021269446；https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=269446 。
