The OW family of arenaviruses includes LASV and lymphocytic choriomeningitis virus (LCMV), a neglected human pathogen distributed worldwide (10, 11) , while the NW family of arenaviruses includes Junín virus (JUNV) and Machupo virus (MACV), the causative agents of Argentine hemorrhagic fever and Bolivian hemorrhagic fever, respectively (9) .