Lymphocytic choriomeningitis virus (LCMV) is an Old World arenavirus that causes lymphocytic choriomeningitis, a typically mild disease characterized by fever and aseptic meningitis. The virus is an enveloped, single‑stranded bisegmented RNA virus with an ambisense coding strategy and belongs to the family Arenaviridae. Its principal reservoir is the common house mouse (Mus musculus), and humans become infected through exposure to rodent urine, droppings or contaminated nesting materials.
Explanation
LCMV virions are roughly 80‑120 nm, enveloped and contain two single‑stranded RNA segments encoding the viral polymerase, glycoproteins, nucleoprotein and a zinc‑binding protein. The virus was first isolated in 1933 and is classified among the Old World arenaviruses along with Lassa virus. Infection is worldwide wherever infected rodents are present. Transmission occurs primarily by inhalation of aerosols or direct contact with fresh rodent excreta; pet rodents and laboratory mice can also be sources. Person‑to‑person transmission is rare but has been documented via organ transplantation and from mother to fetus. After an incubation period of 1‑2 weeks, illness often presents with fever, malaise, lack of appetite and myalgia. In many cases symptoms resolve, but some patients experience a second phase with meningitis or encephalitis. The case‑fatality rate is low (<1 %), but infection during pregnancy can lead to severe congenital abnormalities or fetal loss. Immunosuppressed individuals may develop systemic disease. There is no specific antiviral therapy; treatment is supportive, and prevention relies on avoiding contact with rodents.
Noteworthy aspects
Most LCMV infections are subclinical or result in a mild febrile illness. Documented outbreaks have occurred among rodent breeders and in facilities housing laboratory mice. A small number of transplant‑related clusters have highlighted the risk of donor screening. Pregnant women infected during the first or second trimester may give birth to infants with hydrocephalus, chorioretinitis and developmental delay. Public health guidance stresses rodent control, proper cleaning of areas contaminated by rodent droppings and avoiding pet rodents for households with pregnant women. Lymphocytic choriomeningitis virus is a globally distributed arenavirus carried by common house mice. Although most infections are mild, its potential to cause meningitis and serious congenital disease underscores the importance of rodent control and hygiene. Related Terms: Lassa Virus, Junin Virus, Machupo Virus, Guanarito Virus, Sabia Virus