1. Cumulative Number of Reported Probable Cases of SARS;World Health Organization,2003
2. Countries with laboratory-confirmed MERS cases;Australian Government Department of Health,2019
3. Ebola Virus Disease Distribution Map: Cases of Ebola Virus Disease in Africa Since 1976;Centers for Disease Control and Prevention,2019
4. Pandemic (H1N1) 2009 - update 60;World Health Organization,2009
5. Novel Coronavirus (2019-nCoV) situation reports;World Health Organization,2020