Exploratory Study of Determinants of the Spread of COVID-19 before Shelter-in-Place Orders.

This study explores the impact of relevant characteristics of counties and their relationship with increases in COVID-19 cases before shelter-in-place (SIP) orders in the U.S. The recent emergence of COVID-19 occurs when there is little understanding of the related factors affecting the growth and spread of the disease. These relationships are examined through an analysis of 672 counties before SIP orders were issued. Areas that experienced the most significant transmission of disease are identified, and their characteristics are analyzed. A meaningful relationship was found between the increase of COVID-19 cases and several factors. Average commute time and the proportion of commuters using transit had a positive relationship. Along with other socio-economic factors, such as median house value and proportion of the Black population, several transportation-related factors had a significant association with the transmission of the disease. The decrease rate of total vehicle miles traveled (VMT) before and after SIP orders also had a solid and positive relationship with the expansion of the disease. The findings suggest that planners and transportation service providers must integrate evolving public health considerations into transportation services which affect the increase in the transmission of infectious diseases.