SARS-CoV-2 的神秘传播和第一个COVID-19 浪潮
Jessica T Davis1, Matteo Chinazzi1, Nicola Perra1,2
1Laboratory for the Modeling of Biological and Socio-technical Systems, Northeastern University, Boston, MA, USA.
Nature
|October 25, 2021
概括
早期严重急性呼吸系统冠状病毒2 (SARS-CoV-2) 的社区传播可能在2020年1月发生.国际旅行推动了SARS-CoV-2的引入,监测系统的检测有限.
科学领域:
- 流行病学
- 数学模型
- 公共卫生
背景情况:
- 关于严重急性呼吸综合征冠状病毒2 (SARS-CoV-2) 引入和全球本地传播的初始时间表存在不确定性.
- 2020年初的有限检测和多孔旅行查可能有助于无减轻的SARS-CoV-2传播.
研究的目的:
- 了解全球SARS-CoV-2感染的早期传播情况.
- 确定欧洲和美国的SARS-CoV-2引入和本地传播的时间窗口.
- 通过监测系统估计SARS-CoV-2感染的检测率.
主要方法:
- 利用全球人口转移流行病模型模拟SARS-CoV-2的传播.
- 分析国际旅行模式作为病毒引入的驱动因素.
- 估计不同地理区域的累计感染率.
主要成果:
- 到2020年1月,SARS-CoV-2的社区传播可能存在于欧洲和美国.
- 国际旅行被确定为SARS-CoV-2引入的主要因素,可能发生在2019年12月至2020年1月.
- 到 2020 年 3 月初,只有 1-4% 的 SARS-CoV-2 感染被监测检测到.
- 截至 2020 年 7 月,美国各州的异质感染发作率为 0.78% 至 15.2%,欧洲国家为 0.19% 至 13.2%.
结论:
- 模型结果表明,SARS-CoV-2 在欧洲和美国被引入并以神秘方式传播的时间远早于被检测到的时间.
- 这些发现强调了国际旅行对病毒传播的重要性,并强调了早期监测的局限性.
- 这项研究为开发基于模型的监测系统提供了见解,以加强对未来流行病的测试和应对策略.
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