title: What is new about epidemiology of acute infectious encephalitis?
abstract: OBJECTIVE
  This review aims to describe new features on the epidemiology of encephalitis world-wide. As this neurological presentation is most frequently related to transmitted viruses, surveillance of encephalitis is of major importance to detect their emergence or re-emergence.
  
  
  RESULTS
  Rabies causes one of the most severe types of encephalitis as it is lethal in all cases, and it is endemic in some countries. It was thought that the virus had been eradicated in Western Europe, but it re-emerged in Greece and Italy. Physicians should be aware of this diagnosis in the case of severe encephalitis. Some viruses (Powassan, Nipah, and Hendra) are becoming endemic in some new parts of the world (USA and Australia). Because of their severity, they are healthcare concerns in those countries and for travelers (e.g. in Asia). Finally, a concept is emerging: herpes simplex virus is suspected to be a trigger for autoimmune encephalitis. This is of major importance for the future management of patients (corticosteroids early in the course of the disease?), and the epidemiology of sequelae.
  
  
  CONCLUSIONS
  Encephalitis is a good marker for the detection of emerging infections. New findings about the relationship between herpes simplex virus encephalitis and autoimmune encephalitis open a new concept for a better management of patients.
authors.affiliation: aInfectious Diseases Department, University Hospital and University 1, Grenoble bFrench Institute for Health Surveillance, Saint Maurice, France.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Stahl
authors.forename: Alexandra
authors.initials: A
authors.lastname: Mailles
mesh_terms: D001927:Brain Diseases / Q000453:epidemiology / Q000209:etiology; D004660:Encephalitis / Q000453:epidemiology; D020803:Encephalitis, Herpes Simplex / Q000150:complications / Q000453:epidemiology*; D004675:Encephalitis, Tick-Borne / Q000453:epidemiology*; D050031:Hashimoto Disease / Q000453:epidemiology / Q000209:etiology; D045464:Henipavirus Infections / Q000453:epidemiology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007251:Influenza, Human / Q000453:epidemiology*; D011818:Rabies / Q000453:epidemiology*; D012307:Risk Factors; D014901:West Nile Fever / Q000453:epidemiology*
chemical_list: D007166:Immunosuppressive Agents