The ISG15 gene from the bats, the study showed, is able to reduce production of the SARS CoV-2 virus by 80-90%. By contrast, the ISG15 gene from a human genome showed no antiviral effect in this study.

“Thus, the ISG15 gene is likely one of several factors that contribute to viral disease resistance in bats,” Hiller said. “These promising results can be used as a basis for further experimental studies, which are necessary to decipher the unique adaptations of the bats’ immune system.”