Dear Editor,
It has been more than 1 year since China reported the first case of African swine fever (ASF) infection in August 2018,and the epidemic situation remains severe (China News Service 2019).According to reports from the Min-istry of Agriculture and Rural Affairs,China has reported 160 cases of ASF,which resulted in nearly 1.2 million pigs being killed,as of November 21,2019 (China News Ser-vice 2019).ASF is an acute febrile,hemorrhagic and ful-minating infectious disease,and would reach 100% case fatality rate to pigs (Gallardo et al.2015).The causative pathogen,African swine fever virus (ASFV),is a double-stranded DNA virus with a genome of 170-193 kb belonging to the Asfarviridae family (Galindo and Alonso 2017;Gallardo et al.2015).A recent study has revealed that ASFV maintains a core genome of 102 ORFs and has168 dispensable genes (Wang et al.2019).