Arenaviruses are enveloped viruses with a bisegmented negative-strand RNA genome. Each genome segment, large (∼7.3 kb) and small (∼3.5 kb) uses an ambisense coding strategy to direct synthesis of two polypeptides in opposite direction, separated by a noncoding intergenic region (IGR). The S segment encodes for the viral nucleoprotein (NP) and the glycoprotein precursor (GPC), L segment encodes the viral RNA-dependent RNA polymerase (L polymerase) and the matrix Z protein.
Several arenaviruses cause hemorrhagic fever (HF) disease in humans and pose important public health problems in regions where these viruses are endemic. Lassa virus (LASV) infects several hundred thousand people yearly in West Africa, resulting in a high number of Lassa fever cases that are associated with high morbidity and mortality. Likewise, Junin virus (JUNV) causes Argentine HF, a severe illness endemic to Pampas in Argentina. Moreover, mounting evidence indicates that the worldwide-distributed prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) is a neglected human pathogen of clinical significance. In addition, several arenaviruses, including LASV, JUNV, and LCMV, pose a credible biodefense threat.