Close encounters on the verge of a pandemic: the role of social contacts on the spread and mortality of COVID-19

Close proximity interactions facilitate the spread of COVID-19, which is predominantly transmitted via droplets. In this paper we study to what extend the transmission and mortality of the virus are related to social habits regarding physical interactions. Using regional data for a maximum of 8 European countries we find that a standard deviation increase in the percentage of people having daily face-to-face contacts raises COVID-19 cases by 10% but does not affect the number of fatalities. Analyzing the effects by type of contact, we observe that only the interactions with friends are relevant for the transmission and mortality of the virus. Additionally, our results show that this impact is reinforced by the presence of inter-generational families in the region. Finally, we find evidence of a negative relationship between civic habits and the growth rate of contagion between April and June 2020.