A form of meningitis caused by lymphocytic choriomeningitis virus. mice and other rodents serve as the natural hosts, and infection in humans usually occurs through inhalation or ingestion of infectious particles. Clinical manifestations include an influenza-like syndrome followed by stiff neck, alterations of mentation, ataxia, and incontinence. Maternal infections may result in fetal malformations and injury, including neonatal hydrocephalus, aqueductal stenosis, chorioretinitis, and microcephaly. (From Joynt, Clinical Neurology, 1996, Ch26, pp1-3)