The Role of Social Behaviour in Mediating the Effect of Weather on COVID-19 Infections

34 Pages Posted: 14 May 2021 Last revised: 22 Jun 2021

See all articles by Simone Ferro

Simone Ferro

Università degli Studi di Milano

Chiara Serra

European University Institute - Economics Department (ECO); Bocconi University DONDENA - Carlo F. Dondena Centre for Research on Social Dynamics

Date Written: May 7, 2021

Abstract

We combine mobile locations, weather data, and COVID-19 confirmed cases in a transformed two-way fixed effects mediation model to estimate the causal impact of weather on the COVID-19 infection rate in the United States, disentangling its direct impact from the indirect effect via the endogenous response of social activity. We show that, while temperature has a negative impact on viral infectiousness, it also increases the amount of time individuals spend out of home, which instead favours the spread of the virus. This second channel substantially attenuates the beneficial effect of temperature in curbing the spread of the virus, offsetting half of the potential seasonal fluctuations in the reproduction rate. The mediation role of social activity is particularly relevant when viral incidence is low, while it becomes negligible when the epidemiological situation is more serious. Wind speed and precipitation, despite being significant predictors of social activity, do not induce sufficient variation to affect infections. Estimates are robust to an alternative definition of social activity based on the number of visits to indoor venues. This suggests that our results are not driven by individuals spending less time indoors on warmer days, leaving a biological effect of temperature on the virus as the most probable mechanism. Finally, our estimates show that school closures and lockdowns are effective in reducing infections.

Note:
Funding Statement: This work received no specific funding or grant from any funding agency in the public, commercial, or not-for-profit sectors.

Declaration of Interests: The authors declare no competing interests.

Keywords: COVID-19, Seasonality, Viral Infections, Weather, Social Activity, Human Mobility

JEL Classification: I10, I12, I18

Suggested Citation

Ferro, Simone and Serra, Chiara and Serra, Chiara, The Role of Social Behaviour in Mediating the Effect of Weather on COVID-19 Infections (May 7, 2021). Available at SSRN: https://ssrn.com/abstract=3834552 or http://dx.doi.org/10.2139/ssrn.3834552

Simone Ferro

Università degli Studi di Milano ( email )

via Festa del Perdono, 7
Milano
Italy

Chiara Serra (Contact Author)

Bocconi University DONDENA - Carlo F. Dondena Centre for Research on Social Dynamics ( email )

Via Roentgen 1
Milan, 20136
Italy

European University Institute - Economics Department (ECO) ( email )

Villa San Paolo
Via della Piazzuola 43
50133 Florence
Italy

Do you have a job opening that you would like to promote on SSRN?

Paper statistics

Downloads
63
Abstract Views
641
rank
460,902
PlumX Metrics