The filoviruses, Ebola viruses and Marburg viruses, are emerging, zoonotic negative-strand RNA viruses. As the 2014 West Africa Ebola virus outbreak makes clear, the unique virulence and high transmissibility of these viruses makes them unique public health threats. The Basler lab studies filovirus immune evasion and replication mechanisms with the goals of (1) developing therapeutics that target these mechanisms, (2) determining how these mechanisms contribute to viral pathogenesis and (3) understanding how these mechanisms function in different host species.