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West Nile Virus (WNV)

More information...
* Common Questions
* Prevention
* Repellent

What is the West Nile Virus?
West Nile Virus, a virus spread by certain mosquitoes, has been found in birds, humans and some other mammals in Africa, Eastern Europe, and both West and Middle Asia for several decades. Certain types of mosquitoes (Culex species) get the virus by biting infected birds.

Can humans get West Nile Virus?
Although the risk of getting West Nile Virus is low, humans can get West Nile Virus if they are bitten by a mosquito carrying the virus.

What illnesses does the virus cause in humans?
Usually a human infected with the West Nile virus does not become ill, and is only found to have had the virus when a blood test is done.

Less frequently, a person who gets the virus notices flu-like symptoms such fever, headache and aches and pains all over the body. This is called West Nile Fever.

Occasionally, a human with West Nile virus infection develops encephalitis or viral meningitis with symptoms of severe headache, high fever, stiff neck, vomiting, drowsiness, confusion, muscle weakness and/or coma. People with encephalitis or meningitis are very ill and require medical attention.

Can anything be done to control the spread of West Nile Virus?

  • Help control the mosquito population by eliminating mosquito breeding grounds and places where they gather.
  • Protect yourself and your family from mosquito bites.

What type of clothing should be worn to prevent mosquito bites?

  • Long-sleeved shirts and long pants.
  • Hats, especially for those with thin or missing hair.
  • Light coloured clothing does not attract mosquitoes as much as dark clothing.
  • A small amount of insect repellent can be applied to cuffs and collars to discourage mosquitoes from climbing under clothing to feed.

How can I help control the mosquito population?

  • Change the water in birdbaths twice weekly.
  • Empty water twice weekly from containers or sites where water may collect such as wheelbarrows, children's toys, pet bowls, wading pools, etc.
  • Cover rain barrels tightly with mosquito screening and put screening over the out flow of the down spout.
  • Remove old tires or drill holes in them so water will drain.
  • Clean or repair eaves where water may become stagnant.
  • Fill tree holes with sand so they can't collect rainwater.
  • Prevent ruts from forming in driveways where water can collect.
  • Collections of water that cannot be dumped or drained and are not directly accessible by pets can be treated by adding a few drops of dish detergent, to reduce surface tension of the water and help prevent mosquito breeding.

What birds are most likely to be infected with West Nile Virus?
The most commonly infected birds are crows, blue jays and ravens.

If a dead bird is seen outdoors, is it likely to have died from West Nile virus?
No, there are many reasons for birds to die including several bird diseases, being involved in an accident or simply becoming old.

Even in areas where the West Nile virus is found, not all dead birds found will have died from the virus.

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