Infection of HMVEC-Ls and HUVECs indicate that at least some of the hantaviruses that cause disease in humans (e.g., HTNV, Andes virus [ANDV], SNV, New York-1 virus [NY-1V], PUUV, and SEOV) delay induction of factors in the type I IFN pathway (e.g., production of IFN-α, IFN-β, and MxA) as compared with hantaviruses that cause no known disease in humans (e.g., TULV and Prospect Hill virus [PHV]) [36], [38]–[41]. This evidence concerns the gene IFNB1 and infection.