“…Due to the characteristics of strong operability, low biological risk, convenient detection, and high sensitivity, pseudoviruses have been widely used in the research of highly pathogenic viruses, such as SARS ( Kobinger et al, 2007 ), MERS ( Fan et al, 2018 ), Ebola ( Liu et al, 2017 ), Influenza ( Lu and Jiang, 2013 ), Chikungunya ( Wu et al, 2017 ), Hantan and Seoul Viruses ( Ning et al, 2021 ), and especially in those newly discovered, high-infectious viruses. For example, during the outbreak of SARS-CoV-2, the research of live virus must be carried out in the biosafety level (BSL) 3 facilities, and mutant live viruses are very difficult to obtain.…”