Social Distancing Has Merely Stabilized COVID-19 in the US

Wagner, A. B.; Hill, E. L.; Ryan, S. E.; Sun, Z.; Deng, G.; Bhadane, S.; Martinez, V. H.; Wu, P.; Li, D.; Anand, A.; Acharya, J.; Matteson, D. S.

Social distancing measures, with varying degrees of restriction, have been imposed around the world in order to stem the spread of COVID-19. In this work we analyze the effect of current social distancing measures in the United States. We quantify the reduction in doubling rate, by state, that is associated with social distancing. We find that social distancing is associated with a statistically-significant reduction in the doubling rate for all but three states. At the same time, we do not find significant evidence that social distancing has resulted in a reduction in the number of daily confirmed cases. Instead, social distancing has merely stabilized the spread of the disease. We provide an illustration of our findings for each state, including point estimates of the effective reproduction number, R, both with and without social distancing. We also discuss the policy implications of our findings.