Lymphocytic choriomeningitis virus is perhaps the best known arenavirus. This was the first of the arenaviruses to be isolated, in 1933 during the study of samples from a St. Louis encephalitis epidemic. This virus is distributed throughout the world, especially in Europe and the Americas, in the common house mice species,Mus musculus and Mus domesticus. LCMV has served as a research tool for learning about the immune system, providing an important model for studies of virus-induced immune complex disease, the role of the MHC complex, persistent infections, and immunological tolerance.
Human infection with LCMV can be asymptomatic, but may be associated with three distinct syndromes. The initial phase of an influenza-like syndrome is characterized by fever, myalgia, malaise, and headache. Cough, sore throat, and chest pain may also occur. The second syndrome commonly associated with LCMV, but not commonly caused by this virus is aseptic meningitis. Although LCM is usually thought of as a viral meningitis, deep neurological involvement is manifest in perhaps only 10% of cases. In rarer cases, severe encephalomyelitis has been diagnosed in persons infected with the virus.
Colonies of hamsters and immunocompromised mice in the United States have had a particular problem with LCMV infection, resulting in failed research protocols, and more seriously, clinical disease in laboratory personnel. Many human disease episodes, sometimes involving several hundred cases, have been recorded as the popularity of hamsters as pets has increased.
LCMV is one arenavirus which has been shown to infect the fetus of a pregnant rodent if the mother is viremic. In some situations this infection can result in fetal death, thus it is not surprising that the impact of infection on a human fetus is also often severe. It has recently been shown that LCMV infection of the human fetus can be associated with both fetal death and fatal neonatal infection.
For more information on LCMV, link on to a Virology website suggested on the ARENAVIRUS homepage.