Department of Neurorehabilitation, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325027, China.
Department of Respiratory and Critical Care Medicine, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325027, China.
Can Respir J. 2020 Sep 19;2020:2045341. doi: 10.1155/2020/2045341. eCollection 2020.
Coronavirus disease 2019 (COVID-19), caused by the novel coronavirus SARS-CoV-2, was first identified in December 2019 in Wuhan, China, and has since spread globally, resulting in an ongoing pandemic. However, the study of asymptomatic patients is still rare, and the understanding of its potential transmission risk is still insufficient. In this study, epidemiological investigations were conducted in the Zhejiang province to understand the epidemiology and clinical characteristics of asymptomatic patients with COVID-19.
This retrospective study was carried out on 22 asymptomatic patients and 234 symptomatic patients with COVID-19 who were hospitalized in Zhejiang Duodi Hospital from January 21 to March 16, 2020. The characteristics of epidemiology, demography, clinical manifestations, and laboratory data of mild patients were compared and analyzed.
The median age was 28 years in asymptomatic patients and 48 years in symptomatic patients. The proportion who were female was 77.3% in asymptomatic patients and 36.3% in symptomatic patients ( < 0.001). The proportion of patients with coexisting diseases was 4.5% in asymptomatic patients and 38.0% in symptomatic patients (=0.002). The proportion of patients with increased CRP was 13.6% in the asymptomatic group and 61.1% in the symptomatic group ( < 0.001). The proportion of patients received antiviral therapy was 45.5% in the asymptomatic group and 97.9% in the symptomatic group ( < 0.001). The proportion of patients received oxygen therapy was 22.7% in the asymptomatic group and 99.1% in symptomatic patients ( < 0.001). By March 16, 2020, all patients were discharged from the hospital, and no symptoms had appeared in the asymptomatic patients during hospitalization. The median course of infection to discharge was 21.5 days in asymptomatic patients and 22 days in symptomatic patients.
Asymptomatic patients are also infectious; relying only on clinical symptoms, blood cell tests, and radiology examination will lead to misdiagnosis of most patients, leading to the spread of the virus. Investigation of medical history is the best strategy for screening asymptomatic patients, especially young people, women, and people without coexisting disease, who are more likely to be asymptomatic when infected. Although the prognosis is good, isolation is critical for asymptomatic patients, and it is important not to end isolation early before a nucleic acid test turns negative.
由新型冠状病毒 SARS-CoV-2 引起的 2019 年冠状病毒病（COVID-19）于 2019 年 12 月在中国武汉首次被发现，此后已在全球范围内传播，导致持续大流行。然而，对无症状患者的研究仍然很少，对其潜在传播风险的认识仍然不足。本研究对浙江省的无症状患者进行了流行病学调查，以了解 COVID-19 无症状患者的流行病学和临床特征。
对 2020 年 1 月 21 日至 3 月 16 日在浙江省多地医院住院的 22 例无症状和 234 例有症状 COVID-19 患者进行回顾性研究。比较和分析轻症患者的流行病学、人口统计学、临床表现和实验室数据特征。
无症状患者的中位年龄为 28 岁，有症状患者的中位年龄为 48 岁。无症状患者中女性占 77.3%，有症状患者中女性占 36.3%（<0.001）。合并症患者在无症状患者中的比例为 4.5%，在有症状患者中的比例为 38.0%（=0.002）。CRP 升高患者在无症状组中的比例为 13.6%，在有症状组中的比例为 61.1%（<0.001）。接受抗病毒治疗的患者在无症状组中的比例为 45.5%，在有症状组中的比例为 97.9%（<0.001）。接受氧疗的患者在无症状组中的比例为 22.7%，在有症状组中的比例为 99.1%（<0.001）。截至 2020 年 3 月 16 日，所有患者均已出院，无症状患者住院期间无任何症状。无症状患者的中位感染至出院时间为 21.5 天，有症状患者为 22 天。
无症状患者也具有传染性；仅依靠临床症状、血常规检查和影像学检查会导致大多数患者误诊，从而导致病毒传播。调查病史是筛查无症状患者的最佳策略，特别是对于年轻人、女性和没有合并症的人群，这些人在感染时更有可能无症状。虽然预后良好，但对无症状患者进行隔离至关重要，在核酸检测转为阴性之前，切勿过早结束隔离。
