The Arenaviridae family consists of a group of viruses that are primarily transmitted to humans through contact with rodent excreta, such as urine or droppings. These viruses are known to cause various diseases, including Lassa fever and Argentine hemorrhagic fever, which can lead to severe illness and, in some cases, death. Arenaviruses are characterized by their segmented RNA genomes and are classified into two main groups: Old World and New World arenaviruses. The Old World group includes viruses like Lassa virus, while the New World group includes Junin virus. These viruses can be studied for their potential use in research and vaccine development.