Vertical social distancing policy is ineffective to contain the COVID-19 pandemic

Abstract

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.

Distanciamento social, uso de máscaras e higienização das mãos entre participantes do Estudo Longitudinal da Saúde dos Idosos Brasileiros: iniciativa ELSI-COVID-19

“…Results suggested the adoption of vertical distancing is marginally more effective in reducing transmission than no social isolation. In contrast, the greatest potential for reducing transmission is observed for horizontal distancing 23 . This simulation is in line with international experience, indicating greater effectiveness of horizontal isolation over vertical isolation for flattening the epidemic curve 24,25,26,27,28 .…”

“…Cad. Saúde Pública 2020; 36 Sup 3:e00193920 In Brazil, there is a debate on whether policies aimed at vertical distancing (restricting contact for older people or those with other vulnerabilities), as opposed to horizontal distancing (for everyone) would be sufficient to contain the spread of the virus and decrease mortality associated with it 23 . A mathematical simulation, based on data from the city of Belo Horizonte, compared three scenarios: no social distancing, vertical distancing (selected), and horizontal distancing (all age groups).…”

Association Between Air Pollution in Lima and the High Incidence of COVID-19: Findings from a Post Hoc Analysis

“…In numerical simulations, in a city within Brazil, three scenarios were compared: first was the vertical distancing policy, where only older people are distanced; the second involved the horizontal distancing policy where all age groups adhere to social distancing; and the third involved a control scenario wherein no intervention was undertaken to distance people. Horizontal distancing, if applied with the same intensity in all age groups, significantly reduced the total number of infected people by "flattening the disease growth curve"; however, vertical distancing or non-distancing did not show this effect [ 30 ].…”

Comportamentos em saúde e adoção de medidas de proteção individual durante a pandemia do novo coronavírus: iniciativa ELSI-COVID-19

“…In any case, as of June 13th, 2020, Brazil ranked second in the world in the number of COVID-19 cases (850,514) and deaths (41,828) 26 , which demonstrates the need for greater adherence to physical distancing measures. Evidence indicates that social distancing is effective for reducing the spread of the virus and delaying the increase in the number of cases 4,27,28 , although the sustainability of this measure depends on the implementation of social protection policies, which should be considered by governments 29 .…”