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West Nile virus

Last reviewed: 12 Nov 2024
Last updated: 10 Aug 2023

Summary

Definition

History and exam

Key diagnostic factors

  • fever of sudden onset
  • malaise
  • myalgia
  • arthralgia
  • pharyngitis
  • anorexia
  • abdominal pain
  • visual disturbances
  • headache
  • rash
  • lymphadenopathy
  • conjunctival injection
  • multifocal chorioretinal lesions
  • chorioretinitis and inflammatory vitritis
  • seizures
  • respiratory distress
  • jaundice
  • epigastric tenderness
  • mild confusion
  • disorientation
  • stupor/coma
  • neck stiffness
  • Kernig sign
  • Brudzinski sign
  • muscle paralysis
  • parkinsonism
  • ataxia
  • myoclonus
  • tremors
Full details

Other diagnostic factors

  • nausea/vomiting
  • generalized muscle weakness
  • splenomegaly
  • retinal hemorrhages
  • chest pain, dyspnea, palpitations
  • photophobia
  • depression
  • loss of memory
  • bowel and bladder dysfunction
  • cranial nerve palsies
Full details

Risk factors

  • living in/visiting areas with high West Nile virus activity
  • mosquito bites
  • blood transfusion
  • organ transplant
  • needlestick injuries
Full details

Diagnostic tests

1st tests to order

  • serology
  • cerebrospinal fluid (CSF) analysis
  • complete blood count
  • serum electrolytes
  • liver function tests
  • serum amylase/lipase
Full details

Tests to consider

  • MRI brain
  • CT head
  • viral culture or reverse transcriptase-polymerase chain reaction (RT-PCR)
Full details

Treatment algorithm

ACUTE

West Nile fever

West Nile neuroinvasive disease

Contributors

Authors

Bruce Y. Lee, MD, MBA
Bruce Y. Lee

Professor of Health Policy and Management

Executive Director

Center for Advanced Technology and Communication for Health (CATCH)

Public Health Informatics Computational and Operation Research (PHICOR)

City University of New York (CUNY)

New York

NY

Disclosures

BYL declares that he has no competing interests.

Peer reviewers

Susan Stramer, PhD

Executive Scientific Officer

American Red Cross

Gaithersburg

MD

Disclosures

SS declares that she has no competing interests.

  • Differentials

    • Herpes simplex encephalitis
    • St. Louis encephalitis
    • Eastern equine encephalitis
    More Differentials
  • Guidelines

    • West Nile virus: information for healthcare providers
    • West Nile virus surveillance and control guidelines
    More Guidelines
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