Treatment of West Nile virus

Access information on how West Nile virus is diagnosed and how it is treated.

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How is West Nile virus diagnosed?

Health care providers diagnose West Nile virus infection based on:

  • the patient's symptoms
  • where (geographic location) and when (time of year) they were likely bitten
  • the results of laboratory tests

How is West Nile virus treated?

There is no specific treatment or vaccine for West Nile virus infection in humans. Patients are treated for their symptoms.

Mild symptoms

You may have mild symptoms like:

  • low fever
  • body aches

You are most likely to get better in a few days. In some cases of mild illness, recovery times can be somewhat longer (weeks or months).

Over-the-counter pain relievers can be used to reduce your fever and discomfort.

Severe symptoms

See a health care provider right away if you have more serious symptoms like:

  • rapid onset of severe headache
  • high fever
  • stiff neck
  • nausea and/or vomiting
  • difficulty swallowing
  • drowsiness
  • confusion

Other serious symptoms include:

  • loss of consciousness
  • lack of coordination
  • muscle weakness
  • paralysis

 A blood test can confirm whether West Nile virus is present.

Serious cases are treated with supportive therapies, including:

  • injecting fluids directly into the veins
  • fluids
  • medication
  • breathing support

Hospitalization or nursing care may be necessary.

Long-term effects

West Nile virus is a relatively new disease in North America. Its long-term effects are not fully understood. Most people, even those with serious symptoms and health effects, recover completely. Others experience ongoing health problems.

These problems may include:

  • physical effects, such as:
    • long-term muscle weakness and paralysis
    • tiredness 
    • headache
  • mental effects, such as:
    • confusion
    • depression
    • problems with concentration and memory loss
  • functional effects, such as:
    • difficulty with preparing meals
    • reduced ability to do outdoor physical activities
    • trouble doing daily tasks e.g. shopping

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