Prediction of the Epidemic of COVID-19 Based on Quarantined Surveillance in China

Rui Li; Wenliang Lu; Xifei Yang; Peihua Feng; Ozarina Muqimova; Xiaoping Chen; Gang Wei

The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.02. 27.20027169 doi: medRxiv preprint There is no quarantined measure in the early stage of the epidemic,so R0,as the basic reproductive index,is often high for SARS-CoV-2, 6,7 and there is a significant difference between in Hubei and in non-Hubei areas,but both decrease gradually with the strengthening of isolated measures. 8, 9 We forecasted the epidemic of COVID-19 by modified SEIR model 10,11 and current clinical and epidemiological data on COVID-19,involved in two practical factors to correct the model:1)considering the infectivity during incubation period 12 ,2)considering the influence on the epidemic from strict quarantined measures.It had been confirmed that both the latent and the infected are infectious.We assumed that both were with the same infectivity. According to the epidemic data before Feb.1,2020,it indicated that the probability from the exposed to the infected was 1.7%, 13,14 and the average incubation period was 7 days,and the average hospital stay was 14 days. 15, 16 The average daily contact rate of the infected was 6,referring to the statistical data from CCDC in the early stage of SARS epidemic in 2003. 17,18, 19 However,the population density in Hubei Province was 2.3 times the national average, so the daily contact rate in Hubei was 13.8,and the average daily contact rate of the latent was twice as the infected.The calculation method was R0 = average daily contact rate× probability of the exposed to the infected ×infection period. The average infection period was 21 days. Therefore, R0 was 4.9-9.9 in Hubei,but 2. author/funder, who has granted medRxiv a license to display the preprint in perpetuity.