ABSTRACT
Objective To determine the differences in the epidemiological characteristics of asymptomatic patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19) patients. Methods The relevant data of asymptomatic SARS-CoV-2 transmission literature in PubMed, Web of Science, CNKI, VIP medicine and Wanfang medical database were extracted as of August 1, 2020. Epidemiological information was screened and extracted according to pre-established inclusion and exclusion criteria. Age, gender, virus shedding duration and virual load of asymptomatic carriers were summarized and analyzed. Results A total of 38 articles met the criteria, 17 of which were asymptomatic case reports related to the virus shedding duration. Compared with symptomatic infected persons, asymptomatic individuals were younger [Weighted Mean Difference (WMD), WMD=-5.27, 95% CI: -9.78--0.76, P < 0.001] and the viral load was lower (WMD=2.36, 95% CI: 0.65-4.07, P=0.007). The virus shedding duration of asymptomatic individuals (median=11 days) was shorter than symptomatic patients (median=16 days). Conclusion Asymptomatic individuals with SARS-CoV-2 were younger, had a lower viral load and a shorter virus shedding duration than COVID-19 patients. © 2021, Publication Centre of Anhui Medical University. All rights reserved.