Weather and Policy Influences on Mobility during the U.S. COVID-19 Pandemic

Abstract

As the novel coronavirus SARS-CoV-2 continues to proliferate across the globe, it is a struggle to predict and prevent its spread. The successes of mobility interventions demonstrate how policies can help limit the person-to-person interactions that are essential to infection. With significant community spread, experts predict this virus will continue to be a threat until a safe and effective vaccine has been developed and widely deployed. We aim to understand mobility changes, measured via mobile device tracking, during the first major quarantine period in the United States by assessing how people changed their behavior in response to policies and to weather. Here we show that consistent national messaging was associated with consistent national behavioral change, regardless of local policy. Furthermore, while behavior changed with favorable weather conditions generally the changes did not increase encounters between people. The independence of encounters and temperatures suggests that behavioral changes will not impact any direct physical modulation of transmission by weather as the pandemic continues. Both of these results are encouraging for the potential of the country to be able to curb the virus with clear national messaging.