Psychological intervention

China

Archaeology

Psychiatry

Economics

Development economics

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

Business

Coronavirus disease 2019 (COVID-19)

Geography

Demographic economics

Public economics

Infectious disease (medical specialty)

Medicine

Economic growth

Pandemic

Disease

Pathology

Nature

Governments around the world are responding to the coronavirus disease 2019 (COVID-19) pandemic1, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with unprecedented policies designed to slow the growth rate of infections. Many policies, such as closing schools and restricting populations to their homes, impose large and visible costs on society; however, their benefits cannot be directly observed and are currently understood only through process-based simulations2–4. Here we compile data on 1,700 local, regional and national non-pharmaceutical interventions that were deployed in the ongoing pandemic across localities in China, South Korea, Italy, Iran, France and the United States. We then apply reduced-form econometric methods, commonly used to measure the effect of policies on economic growth5,6, to empirically evaluate the effect that these anti-contagion policies have had on the growth rate of infections. In the absence of policy actions, we estimate that early infections of COVID-19 exhibit exponential growth rates of approximately 38% per day. We find that anti-contagion policies have significantly and substantially slowed this growth. Some policies have different effects on different populations, but we obtain consistent evidence that the policy packages that were deployed to reduce the rate of transmission achieved large, beneficial and measurable health outcomes. We estimate that across these 6 countries, interventions prevented or delayed on the order of 61 million confirmed cases, corresponding to averting approximately 495 million total infections. These findings may help to inform decisions regarding whether or when these policies should be deployed, intensified or lifted, and they can support policy-making in the more than 180 other countries in which COVID-19 has been reported7. Analyses of COVID-19 infection rates show that non-pharmaceutical interventions achieved large, beneficial and measurable health outcomes in China, South Korea, Italy, Iran, France and the United States; these results may inform decisions on whether or when these interventions should be deployed, intensified or lifted.

The effect of large-scale anti-contagion policies on the COVID-19 pandemic