Departamento de Estatística, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Departamento de Estatística, Física e Matemática, Universidade Federal de São João del-Rei, Ouro Branco, Brazil.
Cad Saude Publica. 2020;36(5):e00084420. doi: 10.1590/0102-311x00084420. Epub 2020 May 18.
Considering numerical simulations, this study shows that the so-called vertical social distancing health policy is ineffective to contain the COVID-19 pandemic. We present the SEIR-Net model, for a network of social group interactions, as a development of the classic mathematical model of SEIR epidemics (Susceptible-Exposed-Infected (symptomatic and asymptomatic)-Removed). In the SEIR-Net model, we can simulate social contacts between groups divided by age groups and analyze different strategies of social distancing. In the vertical distancing policy, only older people are distanced, whereas in the horizontal distancing policy all age groups adhere to social distancing. These two scenarios are compared to a control scenario in which no intervention is made to distance people. The vertical distancing scenario is almost as bad as the control, both in terms of people infected and in the acceleration of cases. On the other hand, horizontal distancing, if applied with the same intensity in all age groups, significantly reduces the total infected people "flattening the disease growth curve". Our analysis considers the city of Belo Horizonte, Minas Gerais State, Brazil, but similar conclusions apply to other cities as well. Code implementation of the model in R-language is provided in the supplementary material.
考虑到数值模拟,本研究表明,所谓的垂直社交距离卫生政策对于遏制 COVID-19 大流行是无效的。我们提出了 SEIR-Net 模型,用于社交群体相互作用的网络,作为 SEIR 传染病经典数学模型的发展(易感-暴露-感染(有症状和无症状)-清除)。在 SEIR-Net 模型中,我们可以模拟按年龄组划分的群体之间的社会接触,并分析不同的社交距离策略。在垂直距离政策中,只有老年人被隔离,而在水平距离政策中,所有年龄组都遵守社交距离。将这两种情况与不采取任何干预措施隔离人群的对照情况进行比较。垂直距离政策与对照情况一样糟糕,无论是在感染人数还是在病例加速方面。另一方面,如果在所有年龄组中以相同的强度实施水平距离,会显著减少总感染人数,“使疾病增长曲线变平”。我们的分析考虑了巴西米纳斯吉拉斯州贝洛奥里藏特市,但类似的结论也适用于其他城市。模型的 R 语言代码实现可在补充材料中获得。