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Western equine encephalitis

Disease definition

An acute arboviral infection caused by an alphavirus of the Togaviridae family transmitted by an infected mosquito, that more frequently affects children and that is characterized by the presence of mild flulike symptoms (fever, chills, headache, nausea, vomiting, and anorexia) but that can progress to weakness, altered mental status, photophobia, mental confusion, seizures, somnolence, coma and/or even death. The disease can leave neurological sequelae, mainly in infants and children, such as seizures, spasticity or behavioral disorders.


Classification level: Disorder
  • Synonym(s):
    • Western equine encephalomyelitis
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Not applicable 
  • Age of onset: All ages
  • ICD-10: A83.1
  • OMIM: -
  • UMLS: C0153064
  • MeSH: -
  • GARD: 7888
  • MedDRA: 10014614

Detailed information


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