The impact of public health interventions in the Nordic countries during the first year of SARS-CoV-2 transmission and evolution.
The impact of public health interventions in the Nordic countries during the first year of SARS-CoV-2 transmission and evolution.
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DOI：
10.2807/1560-7917.es.2021.26.44.2001996
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发表时间：
2021-11
期刊：
影响因子：
--
通讯作者：
Pettersson JH
中科院分区：
文献类型：
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作者：
Duchene S;Featherstone L;Freiesleben de Blasio B;Holmes EC;Bohlin J;Pettersson JH
许多国家试图通过非药物干预措施减轻和控制 COVID-19，特别是为了减少人口流动和接触。然而，目前尚不清楚不同的控制策略如何影响致病 SARS-CoV-2 病毒的局部系统动力学。我们的目的是评估各个国家内病毒传播链的持续时间以及各国向其地理邻国输出病毒的程度。我们分析了完整的 SARS-CoV-2 基因组，以推断北欧国家病毒输入和输出的相对频率以及病毒传播动态。我们研究了 COVID-19 大流行第一年丹麦、芬兰、冰岛、挪威和瑞典的病毒进化和系统动力学。北欧国家在控制策略的侵入性方面存在显着差异，我们发现这反映在传播链动态中。例如，与其他北欧国家相比，瑞典更多地依赖基于建议的缓解干预措施，而不是基于立法的缓解干预措施，其传播链数量更多，病例往往更多。这一趋势在 2020 年前 8 个月有所增加。瑞典与丹麦一起是 SARS-CoV-2 的净出口国。挪威和芬兰实施了基于立法的干预措施；他们的传播链动态与其邻国瑞典形成鲜明对比。瑞典构成了一个流行病学和进化的避难所，使病毒能够保持活跃传播并传播到其他地理位置。我们的分析揭示了基因组监测的实用性，其中对活跃传播链的监测是一个关键指标。
Many countries have attempted to mitigate and control COVID-19 through non-pharmaceutical interventions, particularly with the aim of reducing population movement and contact. However, it remains unclear how the different control strategies impacted the local phylodynamics of the causative SARS-CoV-2 virus. We aimed to assess the duration of chains of virus transmission within individual countries and the extent to which countries exported viruses to their geographical neighbours. We analysed complete SARS-CoV-2 genomes to infer the relative frequencies of virus importation and exportation, as well as virus transmission dynamics, in countries of northern Europe. We examined virus evolution and phylodynamics in Denmark, Finland, Iceland, Norway and Sweden during the first year of the COVID-19 pandemic. The Nordic countries differed markedly in the invasiveness of control strategies, which we found reflected in transmission chain dynamics. For example, Sweden, which compared with the other Nordic countries relied more on recommendation-based rather than legislation-based mitigation interventions, had transmission chains that were more numerous and tended to have more cases. This trend increased over the first 8 months of 2020. Together with Denmark, Sweden was a net exporter of SARS-CoV-2. Norway and Finland implemented legislation-based interventions; their transmission chain dynamics were in stark contrast to their neighbouring country Sweden. Sweden constituted an epidemiological and evolutionary refugium that enabled the virus to maintain active transmission and spread to other geographical locations. Our analysis reveals the utility of genomic surveillance where monitoring of active transmission chains is a key metric.