Emerging and re-emerging viral diseases are a public health concern for the whole world and pose a major threat to human health and life.In last decades, numerous major outbreaks of emerging and re-emerging viral diseases with gross public concern were recorded in different regions,including Ebola in western Africa, Zika in South America,H7N9 in China and many Asian countries, and H1N1 influenza worldwide.In particular, coronaviruses were once regarded as the ones that just cause mild symptoms like common cold, but three new types of coronaviruses,which emerged in the 21st century, can cause severe diseases with high fatality and morbidity.Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) emerged in November 2002 in Guangdong, China and caused globally 8098 human infections with 774 deaths (9.6%), and the Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) emerged in 2012 in Saudi Arabia and caused 2494 infections with 858 associated deaths (34.4%) as of November 2019 (WHO 2020a, b).