Guanarito virus is a New World arenavirus that causes Venezuelan hemorrhagic fever. It has a bisegmented negative‑sense RNA genome and is maintained in Zygodontomys brevicauda rodents in Venezuela. Human infection results from contact with contaminated rodent excreta or aerosols.
Explanation
Guanarito virus belongs to the genus Mammarenavirus of the Arenaviridae family. Like other arenaviruses, its virions are enveloped, pleomorphic particles roughly 50–300 nm in diameter and contain two segments of single‑stranded RNA. The small (S) segment encodes the nucleoprotein and glycoprotein precursor, whereas the large (L) segment encodes the viral polymerase and a zinc-binding protein via an ambisense coding arrangement. The virus circulates among short-tailed cane mice (Zygodontomys brevicauda) that inhabit cultivated fields in the central Venezuelan plains. Rodents shed virus in urine and feces, and humans become infected by inhaling aerosolized excreta or through contact with contaminated grain stores. The incubation period is typically 7–14 days, followed by fever, malaise, headache and bleeding tendencies. Severe cases develop hemorrhagic manifestations, shock and neurological involvement; fatality rates reported during outbreaks have been around 23 %. No licensed vaccine exists, and treatment is mainly supportive, although ribavirin may provide benefit if given early.
Epidemiology and control
Venezuelan hemorrhagic fever was first recognised in the late 1980s when outbreaks occurred in the Portuguese and Barinas states of Venezuela among agricultural communities. The disease is endemic to this region because of the distribution of its rodent host. Unlike some other New World arenaviruses, person-to-person transmission appears to be rare, but health-care workers are advised to use barrier precautions with suspected cases. Control strategies focus on reducing rodent populations around dwellings and protecting stored crops from contamination. Public education campaigns in endemic areas emphasise avoiding contact with rodent droppings and seeking medical care promptly when febrile illness with bleeding symptoms occurs. Guanarito virus remains confined to rural Venezuela, but its capacity to cause severe hemorrhagic fever warrants continued surveillance and public health preparedness. Understanding its ecology and transmission helps prevent disease and informs development of potential vaccines and therapeutics. Related Terms: Machupo virus, Junin virus, Sabia virus, Chapare virus, Lujo virus