Estimating and explaining the spread of COVID-19 at the county level in the USA

Abstract

Ives and Bozzuto estimate the spread rate of COVID-19 in the USA at the start of the epidemic, extrapolating values of R0 for 3109 counties during the period before measures were taken to reduce the spread. Most of predictive variation in county-level values of R0 is explained by population density and spatial location, with differences among locations associated with differences among strains of SARS-CoV-2.