A Lockdown a Day Keeps the Doctor Away: The Effectiveness of Non-Pharmaceutical Interventions During the COVID-19 Pandemic

Countries have employed a variety of non-pharmaceutical interventions (NPIs) in order to curtail the Covid-19 pandemic. However, the success of individual measures in reducing the number of infections remains controversial. This paper exploits a panel data set of 181 countries to estimate the effects of twelve NPIs on the spread of the disease in 2020. The employed fixed effects estimation greatly reduces endogeneity concerns. While almost all measures had a dampening effect on the reproduction rate of the virus, school closings and restrictions on gatherings were most effective, followed by international travel restrictions and contact tracing. The obligation to wear face masks was more effective during the second wave. Measures requiring significant resources, such as testing, were more effective in developed countries.