Department of Radiology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, 610072, China.
Department of Radiology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, 610072, China.
Travel Med Infect Dis. 2020 Sep-Oct;37:101754. doi: 10.1016/j.tmaid.2020.101754. Epub 2020 May 31.
Asymptomatic infection of SARS-CoV-2 has become a concern worldwide. This study aims to compare the epidemiology and the clinical characteristics of SARS-CoV-2 infection in asymptomatic and symptomatic individuals.
A total of 511 confirmed SARS-CoV-2 infection cases, including 100 asymptomatic (by the time of the pathogenic tests) and 411 symptomatic individuals were consecutively enrolled from January 25 to February 20, 2020 from hospitals in 21 cities and 47 counties or districts in Sichuan Province. Epidemiological and clinical characteristics were compared.
Compared to the symptomatic patients, the asymptomatic cases were younger (P < 0.001), had similar co-morbidity percentages (P = 0.609), and came from higher altitude areas with lower population mobility (P < 0.001) with better defined epidemiological history (P < 0.001). 27.4% of well-documented asymptomatic cases developed delayed symptoms after the pathogenic diagnosis. 60% of asymptomatic cases demonstrated findings of pneumonia on the initial chest CT, including well-recognized features of coronavirus disease-19. None of the asymptomatic individuals died. Two elderly individuals with initially asymptomatic infection developed severe symptoms during hospitalization. One case of possible virus transmission by a patient during the incubation period was highly suspected.
The epidemiological and clinical findings highlight the significance of asymptomatic infection with SARS-CoV-2. Inspecting the epidemiological history would facilitate the identification of asymptomatic cases. Evidence supports the chest CT scans for confirmed asymptomatic cases to evaluate the extent of lung involvement.
SARS-CoV-2 的无症状感染已成为全球关注的问题。本研究旨在比较无症状和有症状个体中 SARS-CoV-2 感染的流行病学和临床特征。
2020 年 1 月 25 日至 2 月 20 日，连续纳入来自四川省 21 个城市和 47 个县/区的 511 例确诊 SARS-CoV-2 感染病例，包括 100 例无症状（在病原体检测时）和 411 例有症状个体。比较流行病学和临床特征。
与有症状患者相比，无症状患者年龄较小（P<0.001），合并症百分比相似（P=0.609），来自海拔较高、人口流动性较低的地区，具有更好定义的流行病学史（P<0.001）。27.4%的有明确记录的无症状病例在病原体诊断后出现延迟症状。60%的无症状病例在初始胸部 CT 上表现出肺炎表现，包括冠状病毒病-19 的公认特征。所有无症状个体均未死亡。2 例最初无症状感染的老年患者在住院期间出现严重症状。高度怀疑 1 例潜伏期患者发生病毒传播。
流行病学和临床发现强调了 SARS-CoV-2 无症状感染的重要性。检查流行病学史有助于识别无症状病例。证据支持对确诊的无症状病例进行胸部 CT 扫描以评估肺部受累程度。
