Impacts of social and economic factors on the transmission of coronavirus disease (COVID-19) in China

Yun Qiu; Xi Chen; Wei Shi

Second, our paper complements the epidemiologic studies on the basic reproduction number of COVID-19. Using data on the first 425 COVID-19 patients by January 22, Li et al. (2020) estimate a basic reproduction number of 2.2. Based on time-series data on the number of COVID-19 cases in mainland China from January 10 to January 24, Zhao et al. (2020) estimate that the mean reproduction number ranges from 2.24 to 3.58. Given the short time since the beginning of the COVID-19 outbreak, more research in this area is required to assess the dynamics of transmission and its implications on how the COVID-19 outbreak will evolve McGoogan, 2020, Wu et al., 2020b) . Several recent studies have examined the effect of population movement on the spread of COVID-19 (Zhan et al., 2020 . Our analysis relies on spatially disaggregated data in a longer period, and the instrumental variable approach we use imposes fewer restrictions on the relationship between the unobserved determinants of new cases and the number of cases in the past. Using exogenous temperature, wind speed and precipitation in the preceding third and fourth weeks as the instruments, we find that in the January 19 -February 1 subsample, one new infection leads to 1.465 more cases within one week and the effect on the second week is not definitive.