Estimating the Effect of Social Distancing Interventions on COVID-19 in the United States

Abstract

Since its global emergence in 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused multiple epidemics in the United States. Because medical treatments for the virus are still emerging and a vaccine is not yet available, state and local governments have sought to limit its spread by enacting various social distancing interventions such as school closures and lockdown, but the effectiveness of these interventions is unknown. We applied an established, semi-mechanistic Bayesian hierarchical model of these interventions on SARS-CoV-2 spread in Europe to the United States. We estimated the effect of interventions across all states, contrasted the estimated reproduction number, Rt , for each state before and after lockdown, and contrasted predicted future fatalities with actual fatalities as a check on the model's validity. Overall, school closures and lockdown are the only interventions modeled that have a reliable impact on Rt , and lockdown appears to have played a key role in reducing Rt below 1.0. We conclude that reversal of lockdown, without implementation of additional, equally effective interventions, will enable continued, sustained transmission of SARS-CoV-2 in the United States.

Phylodynamic analysis of SARS-CoV-2 spread in Rio de Janeiro, Brazil, highlights how metropolitan areas act as dispersal hubs for new variants

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Effects of transport-related COVID-19 policy measures: A case study of six developed countries

“…Results indicated that mobility restrictions exhibited an inverse relationship with the daily number of newly diagnosed SARS-CoV-2 positive cases only after the second, more effective lockdown during the study period. Olney et al (2021) developed a semi-mechanistic Bayesian hierarchical model to analyze the effect of social distancing measures, such as school closures and lockdowns, on the COVID-19 spread in different states of the US, based on the data of case fatalities from February 29 to April 25, 2020, when some states began reversing their interventions. Model results indicated that lockdowns played a key role in reducing the reproduction number to below 1.0.…”

As diferentes fases, os seus impactos e os desafios da pandemia de covid-19 no Brasil

“…A dinâmica da doença tem variado sob o efeito da introdução de novas variantes do vírus (DAO et al, 2021;SPINELLA;MIO, 2021), das medidas chamadas de 'não farmacológicas' (OLNEY et al, 2021), da vacinação (SPINELLA; MIO, 2021), das vulnerabilidades sociais preexistentes, além da estrutura e do desempenho do próprio sistema de saúde (BRIZZI et al, 2022). Essas condições contextuais alteram as relações entre exposição, infecção, adoecimento e mortalidade.…”