Clinical Data Center, Guangzhou Women and Children's Medical Center, Guangdong Provincial Clinical Research Center for Child Health, Institute of Pediatrics, Guangzhou Medical University, Guangzhou, China.
Medical Research Department, Guangdong Provincial People's Hospital/Guangdong Academy of Medical Sciences, Guangzhou, China.
Front Public Health. 2022 Sep 29;10:925492. doi: 10.3389/fpubh.2022.925492. eCollection 2022.
The dynamic transmission of asymptomatic and symptomatic COVID-19 infections is difficult to quantify because asymptomatic infections are not readily recognized or self-identified. To address this issue, we collected data on asymptomatic and symptomatic infections from four Chinese regions (Beijing, Dalian, Xinjiang, and Guangzhou). These data were considered reliable because the government had implemented large-scale multiple testing during the outbreak in the four regions. We modified the classical susceptible-exposure-infection-recovery model and combined it with mathematical tools to quantitatively analyze the number of infections caused by asymptomatic and symptomatic infections during dynamic transmission, respectively. The results indicated that the ratios of the total number of asymptomatic to symptomatic infections were 0.13:1, 0.48:1, 0.29:1, and 0.15:1, respectively, in the four regions. However, the ratio of the total number of infections caused by asymptomatic and symptomatic infections were 4.64:1, 6.21:1, 1.49:1, and 1.76:1, respectively. Furthermore, the present study describes the daily number of healthy people infected by symptomatic and asymptomatic transmission and the dynamic transmission process. Although there were fewer asymptomatic infections in the four aforementioned regions, their infectivity was found to be significantly higher, implying a greater need for timely screening and control of infections, particularly asymptomatic ones, to contain the spread of COVID-19.
无症状和有症状 COVID-19 感染的动态传播难以量化，因为无症状感染不容易被识别或自我识别。为了解决这个问题，我们从中国的四个地区（北京、大连、新疆和广州）收集了无症状和有症状感染的数据。由于政府在这四个地区爆发期间实施了大规模的多次检测，这些数据被认为是可靠的。我们修改了经典的易感-暴露-感染-恢复模型，并结合数学工具，分别对无症状和有症状感染在动态传播过程中引起的感染数量进行了定量分析。结果表明，四个地区的无症状感染总数与有症状感染总数之比分别为 0.13:1、0.48:1、0.29:1 和 0.15:1。然而，无症状和有症状感染引起的总感染数之比分别为 4.64:1、6.21:1、1.49:1 和 1.76:1。此外，本研究描述了由有症状和无症状传播引起的每日健康人群感染人数和动态传播过程。尽管上述四个地区的无症状感染人数较少，但发现它们的传染性明显更高，这意味着需要及时筛查和控制感染，特别是无症状感染，以遏制 COVID-19 的传播。
