title: Japanese encephalitis virus remains an important cause of encephalitis in Thailand.
abstract: BACKGROUND
  Japanese encephalitis virus (JEV) is endemic in Thailand and prevention strategies include vaccination, vector control, and health education.
  
  
  METHODS
  Between July 2003 and August 2005, we conducted hospital-based surveillance for encephalitis at seven hospitals in Bangkok and Hat Yai. Serum and cerebrospinal (CSF) specimens were tested for evidence of recent JEV infection by immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) and a plaque reduction neutralization test (PRNT).
  
  
  RESULTS
  Of the 147 patients enrolled and tested, 24 (16%) had evidence of acute flavivirus infection: 22 (15%) with JEV and two (1%) with dengue virus. Of the 22 Japanese encephalitis (JE) cases, 10 (46%) were aged ≤ 15 years. The median length of hospital stay was 13 days; one 13-year-old child died. Ten percent of encephalitis patients enrolled in Bangkok hospitals were found to have JEV infection compared to 28% of patients enrolled in hospitals in southern Thailand (p < 0.01). Four (40%) of the 10 children with JE were reported as being vaccinated.
  
  
  CONCLUSIONS
  JEV remains an important cause of encephalitis among hospitalized patients in Thailand. The high proportion of JE among encephalitis cases is concerning and additional public health prevention efforts or expanded vaccination may be needed.
authors.affiliation: Divison of Emerging Infections and Surveillance Services, Centers for Disease Control and Prevention Collaboration, 1600 Clifton Road, MS C-12, Atlanta, GA 30333, USA. SOlsen@cdc.gov
authors.forename: Sonja J
authors.initials: SJ
authors.lastname: Olsen
authors.forename: Krongkaew
authors.initials: K
authors.lastname: Supawat
authors.forename: Angela P
authors.initials: AP
authors.lastname: Campbell
authors.forename: Surapee
authors.initials: S
authors.lastname: Anantapreecha
authors.forename: Sahas
authors.initials: S
authors.lastname: Liamsuwan
authors.forename: Supoch
authors.initials: S
authors.lastname: Tunlayadechanont
authors.forename: Anannit
authors.initials: A
authors.lastname: Visudtibhan
authors.forename: Somsak
authors.initials: S
authors.lastname: Lupthikulthum
authors.forename: Kanlaya
authors.initials: K
authors.lastname: Dhiravibulya
authors.forename: Akravudh
authors.initials: A
authors.lastname: Viriyavejakul
authors.forename: Punnee
authors.initials: P
authors.lastname: Vasiknanonte
authors.forename: Kiatsak
authors.initials: K
authors.lastname: Rajborirug
authors.forename: Veerachai
authors.initials: V
authors.lastname: Watanaveeradej
authors.forename: Chacrin
authors.initials: C
authors.lastname: Nabangchang
authors.forename: Janeen
authors.initials: J
authors.lastname: Laven
authors.forename: Olga
authors.initials: O
authors.lastname: Kosoy
authors.forename: Amanda
authors.initials: A
authors.lastname: Panella
authors.forename: Christine
authors.initials: C
authors.lastname: Ellis
authors.forename: Sununta
authors.initials: S
authors.lastname: Henchaichon
authors.forename: Nino
authors.initials: N
authors.lastname: Khetsuriani
authors.forename: Ann M
authors.initials: AM
authors.lastname: Powers
authors.forename: Scott F
authors.initials: SF
authors.lastname: Dowell
authors.forename: Marc
authors.initials: M
authors.lastname: Fischer
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004664:Encephalitis Virus, Japanese / Q000276:immunology / Q000302:isolation & purification*; D004672:Encephalitis, Japanese / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology; D006801:Humans; D007223:Infant; D022321:Japanese Encephalitis Vaccines / Q000627:therapeutic use; D008875:Middle Aged; D013785:Thailand / Q000453:epidemiology; D055815:Young Adult
chemical_list: D022321:Japanese Encephalitis Vaccines