PDF(Pubmed)
Abstract：
This study aimed to monitor severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral loads and specific serum-antibodies (immunoglobulin [Ig] G and M) among confirmed patients and asymptomatic carriers from returning healthy travelers. The throat swabs, sputum, and stool samples from 57 hospitalized coronavirus disease (COVID-19) patients and 8 asymptomatic carriers, among 170 returning healthy travelers were tested using reverse-transcription real-time polymerase chain reaction. SARS-CoV-2 IgM/IgG antibodies were detected via serum chemiluminescence assay. Sequential results showed higher viral RNA loads in the throat, sputum, and stool samples at 3-12 and 6-21 days after symptom onset among severely ill COVID-19 patients. Shorter viral habitation time (1-8 days) was observed in the oropharyngeal site and intestinal tract of asymptomatic carriers. The IgG and IgM response rates were 19/37 (51.4%) and 23/37 (62.6%) among the 29 confirmed patients and 8 asymptomatic carriers, respectively, within 66 days from symptom or detection onset. The median duration between symptom onset and positive IgG and IgM results was 30 (n=23; interquartile range [IQR]=20-66) and 23 (n=19; IQR=12-28) days, respectively. Of 170 returning healthy-travelers to China, 4.7% were asymptomatic carriers (8/170) within 2 weeks, and the IgG and IgM positivity rate was 12.8% (12/94). IgM/IgG-positivity confirmed 3 suspected SARS-CoV-2 cases, despite negative results for SARS-CoV-2 RNA. Compared with other respiratory viral infectious diseases, COVID-19 has fewer asymptomatic carriers, lower antibody response rates, and a longer antibody production duration in recovered patients and the contacted healthy population. This is an indication of the complexity of COVID-19 transmission.
摘要：
这项研究旨在监测确诊患者和来自返回健康旅行者的无症状携带者中的严重急性呼吸综合征冠状病毒2（SARS-CoV-2）病毒载量和特异性血清抗体（免疫球蛋白[Ig]G和M）。喉咙拭子，痰,57例住院冠状病毒病(COVID-19)患者和8例无症状携带者的粪便样本，使用逆转录实时聚合酶链反应对170名返回的健康旅行者进行了测试。血清化学发光法检测SARS-CoV-2IgM/IgG抗体。序列结果显示喉咙中的病毒RNA载量较高，痰,重症COVID-19患者症状发作后3-12天和6-21天的粪便样本。在无症状携带者的口咽部位和肠道中观察到较短的病毒栖息时间（1-8天）。29例确诊患者和8例无症状携带者的IgG和IgM应答率分别为19/37(51.4%)和23/37(62.6%),分别,在症状或检测发作后66天内。症状发作与IgG和IgM阳性结果之间的中位持续时间为30（n=23；四分位距[IQR]=20-66）和23（n=19；IQR=12-28）天，分别。在170名返回中国的健康旅行者中，4.7%为2周内无症状携带者(8/170)，IgG和IgM阳性率为12.8%(12/94)。IgM/IgG阳性确诊3例疑似SARS-CoV-2,尽管SARS-CoV-2RNA结果呈阴性。与其他呼吸道病毒性传染病相比,COVID-19的无症状携带者较少，较低的抗体反应率，康复患者和接触健康人群的抗体产生持续时间更长。这表明了COVID-19传播的复杂性。
