West Nile virus - Symptoms, Causes, Images, and Treatment Options

Diseases

Highlights & Basics

Key Highlights

West Nile virus is a notifiable condition. Standard precautions should be taken when handling blood, blood products, or other body fluids that might be infected.
Most infections are asymptomatic; however, about 20% of people develop a self-limiting, influenza-like illness. Of these patients, < 1% progress to neuroinvasive disease characterized by encephalitis, meningitis, or flaccid paralysis syndrome (known as West Nile poliomyelitis).
Diagnosis is confirmed with serologic testing in patients with suspected neuroinvasive disease. IgM can be detected in most serum and cerebrospinal fluid (CSF) specimens at the time of clinical presentation.
Treatment is supportive. Patients with neuroinvasive disease require hospitalization, respiratory support, and intravenous fluids. No vaccine or specific antiviral treatment is available.

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History & Exam
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Definition

Epidemiology

Etiology

Pathophysiology

Citations

Key Articles

Hayes EB, Sejvar JJ, Zaki SR, et al. Virology, pathology, and clinical manifestations of West Nile virus disease. Emerg Infect Dis. 2005;11:1174-1179.[Abstract]
Centers for Disease Control and Prevention. West Nile virus surveillance and control guidelines. April 2022 [internet publication].[Full Text]
Centers for Disease Control and Prevention. West Nile virus disease therapeutics: review of the literature for healthcare providers. February 2018 [internet publication].[Full Text]

Other Online Resources

CDC: West Nile virus data and maps
Centers for Disease Control and Prevention: West Nile virus
World Health Organization: West Nile virus

Referenced Articles

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