Comparative Analysis of COVID-19 Transmission Patterns in Three Chinese Regions vs. South Korea,Italy and Iran

Junyu He; Guangwei Chen; Yutong Jiang; Runjie Jin; Mingjun He; Ashton Shortridge; Jiaping Wu; George Christakos

(ii) In the SEIR equations, the exposure rate includes two parts: one part is proportional to the 173 contacts between susceptible and infected individuals (assessed by  1 ), whereas the other part is 174 proportional to the contacts between susceptible and exposed individuals (assessed by  2 ). Since 175 individuals that are confirmed as infected are immediately sent to hospitals for isolation and medical 176 treatment in the three regions of China, it is assumed that the infection transmission rate was always 177 smaller than the exposure transmission rate, i.e.,  1   2 . Specifically, following the current COVID-178 19 literature [27] , it is assumed that  2  5 1 , and that the probability that an exposed individual 179 becomes infected is   1 7 . The cured and dead individuals are removed at the rate (t)  (t) . In the 180 regions of interest, the values of  and  were zero at the beginning ( t  0), i.e.,  0   0  0 . 181 (iii) Given that the COVID-19 disease spread has been controlled in the three regions of China, 182 only data from the first 28-days were taken into account in the present study. For South Korea, Italy 183 and Iran, complete datasets covering the entire countries were considered, including areas in which 184 epidemic spread is still underway.