Favipiravir is a new type of RNA polymerase inhibitor used to treat new and recurrent influenza. It mainly inhibits viral proliferation by blocking viral nucleic acid replication. In the 2014 Ebola outbreak, a female nurse infected with Ebola virus in France and an infected nurse in Spain recovered after taking favipiravir. Preclinical pharmacodynamics shows that favipiravir not only exhibits antiviral activity against seasonal influenza viruses, but also against various influenza viruses of swine origin and highly pathogenic avian influenza, and does not show obvious crossover drug resistance to existing drug-resistant cell lines.