Antiviral activities of type I interferons to SARS-CoV-2 infection

There is an urgent need to identify antivirals to curtail the COVID-19 pandemic. Herein, we report the sensitivity of SARS-CoV-2 to recombinant human interferons alpha and beta (IFN alpha/beta). Treatment with IFN-alpha or IFN-beta at a concentration of 50 international units (IU) per milliliter reduces viral titers by 3.4 log or over 4 log, respectively, in Vero cells. The EC50 of IFN-alpha and IFN-beta treatment is 1.35 IU/ml and 0.76 IU/ml, respectively, in Vero cells. These results suggest that SARS-CoV-2 is more sensitive than many other human pathogenic viruses, including SARS-CoV. Overall, our results demonstrate the potential efficacy of human Type I IFN in suppressing SARS-CoV2 infection, a finding which could inform future treatment options for COVID-19.