Etiology and outcome in 42 children with acute nonbacterial meningoencephalitis.

In a prospective study of 42 cases of childhood meningoencephalitis occurring in 1974 and 1975, a diagnosis of an infectious agent was made in 30 (71%). California virus infections were most common; they were serious illnesses but had few sequelae. Benign illnesses with enteroviruses were also common. Miscellaneous and unknown agents accounted for the most seriously ill patients and for both deaths. Persistent neurologic deficits were unusual. Headaches, malaise, and changes in behavior were common but transient.