Staggered Adoption of Nonpharmaceutical Interventions to Contain COVID-19 Across U.S. Counties: Direct and Spillover Effects

Abstract

We estimate direct and spillover effects of social distancing measures intended to slow the spread of COVID-19 at the U.S. county level using mobility indicators based on cellphone data. We find that spillover effects range between a third and a half of the direct effect depending on the particular outcome or policy considered. Our results suggest that decentralized NPI decisions, which does not internalize externalities generated on surrounding locations, could result in lower NPI implementation and weaker reduction in mobility, and hence more personal contacts and interactions in leisure and work activities, which are the main driver of the COVID-19 transmission.

Note: Funding: Hopkins Business of Health Initiative.

Declaration of Interest: None to declare

Keywords: mobility, spillovers, Non pharmaceutical Interventions, COVID-19, regional policies, place-based policies

JEL Classification: H73, I18, R12