Consistent with our previous data23, the addition of increasing concentrations of anti-YFV ascites fluid in the supernatant of infected Huh7.5 cells from 16 to 40 hours post-infection resulted in a dose-dependent decrease in infectious viral titers (up to 4 log) compared to the addition of 4G2, an antibody that binds to viral Env but is unable to neutralize cell-free virions (Fig. 5A). This evidence concerns the gene ERVW-1 and infection.