Fewer studies have been performed on IFITM1, which can restrict infection by a number of RNA viruses, including hepatitis C virus (28, 29), sheep Jaagsiekte virus (30), HIV (31), Zika virus (24), and influenza viruses (20) but not Rift Valley fever virus (32), Sindbis virus, or Semliki Forest virus (26). This evidence concerns the gene IFITM1 and infection.