Japanese encephalitis virus

Epidemiology

• endemic in most of Asia & parts of western Pacific
• infection follows bite of Colex mosquitoes

Clinical manifestations

• rarely symptomatic
• presentation with non-specific fever with headache
• neurologic symptoms may develop rapidly
  • encephalitis most common
  • focal neurologic signs
    • paresis
    • cranial nerve palsy
    • flaccid paralysis
    • parkinsonism
  • coma
• may present as mild, febrile aseptic meningitis

Laboratory

• Japanese encephalitis virus serology
  • Japanese encephalitis virus IgM in CSF (early)
  • Japanese encephalitis virus IgM in serum (later)
• Japanese encephalitis virus antigen
• Japanese encephalitis virus RNA

Radiology

• MRI of brain
  • thalamic lesions

Management

• Japanese encephalitis virus vaccine

More general terms

• encephalitis virus
• flaviviridae

Additional terms

• Japanese encephalitis virus vaccine (JE-VAX, Ixiaro)