In this study, the COVID-19 cases of Guangdong province, Hubei province and mainland China are obtained from the Health Commission of Guangdong Province (http://wsjkw.gd.gov.cn/), the Health Commission of Hubei Province (http://wjw.hubei.gov.cn/), and the National Health Commission of the People's Republic of China (http://www.nhc.gov.cn/), respectively. The data are from Jan 20, 2020 to present which include the number of the cumulative confirmed cases, the number of the confirmed cases, the number of the cumulative cured cases and the number of cumulative death cases. The numbers of the total population of Guangdong Province, Hubei Province and mainland China are employed at the end of 2018 from the National Bureau of Statistics (http://www.stats.gov.cn/).