[Acute encephalitis in children].

Acute encephalitis is mainly of viral origin. Two groups of are considered: i) primary encephalitis, such as Herpes simplex encephalitis with intra-thecal synthesis of antibodies, and ii) post-viral infection encephalitis or acute disseminated encephalitis with immune dysregulation. The most common clinical presentation (fever, consciousness disturbance and seizures) is not specific and may reveal bacterial meningitis or cerebral abscess which require a specific treatment. Acyclovir has allowed consistant advances in the treatment of herpes encephalitis. Vaccination against selected viral infection, such as measle vaccine, is the only way to prevent acute disseminated encephalitis.