Ebola and Marburg viruses, both filoviruses, are the causative agents of severe hemorrhagic fever.

Rodent models for Ebola and Marburg viruses are often the first choice for initial descriptions of virus pathogenesis and evaluation of antiviral prophylactics and therapeutics.

Rodent models rely on “rodent-adapted” viruses that have been passaged several times through their host until virulence and lethality are achieved.

Rodent-adapted Ebola and Marburg acquire numerous nucleotide/amino acid mutations that contribute to virulence in their rodent host.

VP24 and NP appear to be major virulence factors for ebolaviruses in rodents, whereas VP40 appears to be the major virulence factor for marburgviruses.