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West Nile Virus

West Nile Virus

Download West Nile Virus Facts

West Nile Virus is a potentially serious disease carried by mosquitoes. People get West Nile Virus after being bitten by an infected mosquito or handling a bird that died from West Nile Virus.

Who gets West Nile Virus?

Anyone can get West Nile Virus. People who work outside or participate in outdoor activities are the most likely to get infected, while people over the age of 60 have the greatest risk of severe illness.

What are the symptoms?

Most people don’t show any symptoms of West Nile Virus. Around 20 percent of people will develop flu-like symptoms, including:

  • Fever
  • Head and body aches
  • Joint pains
  • Vomiting
  • Diarrhea
  • Rash

About one percent of people with West Nile Virus develop severe neurologic effects, which are sometimes permanent or fatal. Symptoms of severe West Nile Virus include:

  • High fever
  • Neck stiffness
  • Disorientation
  • Coma
  • Tremors
  • Seizures
  • Paralysis

How is West Nile Virus treated?

There is no specific treatment for West Nile Virus. Most people recover completely, although fatigue and weakness can last for weeks or months.

How can I protect myself from West Nile Virus?

There is no West Nile Virus vaccine, but you can prevent it by avoiding mosquito bites.

  • Use insect repellent containing DEET (less than 35% DEET for adults and less than 15% DEET for children).
  • Wear long-sleeve shirts and pants when mosquitoes may be present.

Be extra careful outside during peak mosquito hours from dusk to dawn. Wear long sleeves, insect repellent and avoid going outside during these hours if possible.

How can I keep mosquitoes away from my home?

Mosquitoes breed in standing water. Empty any containers, tires, birdbaths, gutters and buckets that have collected water. Screen doors and windows can also keep mosquitoes from entering your home.

Avoid overspray of turf and landscapes. This can result in creating longterm puddles in street gutters. Please contact Denver Environmental Health (by calling 3-1-1) if you see multiple sick or dead birds in your neighborhood.

Who should I contact if I believe a family member has West Nile Virus?

Consult your healthcare provider or call Denver Public Health at (303) 602-3614

Sources: Centers for Disease Control & Prevention; Tri-County Health Department; Denver Public Health, Denver Environmental Health.