Special Update - West Nile Virus

1. What is West Nile Virus (WNV) Encephalitis?

West Nile Virus (WNV) Encephalitis is a rare disease caused by a virus. In a small percentage of people infected by the virus, the disease can be serious, even fatal. It was first identified in the United States during the summer of 1999. WNV grows in birds and is transmitted from bird to bird and from birds to humans by mosquitoes.

2. What are the symptoms of WNV Encephalitis?

Mild WNV infections cause fevers, headache, and body aches often with a skin rash and swollen lymph glands. More severe infections can cause headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, paralysis and sometimes, death. The elderly, the very young and those with weakened immune systems are most susceptible to the virus. If you think you have symptoms of WNV seek medical care immediately.

3. Is there treatment for WNV Encephalitis?

Currently there is no vaccine against West Nile Virus and there is no specific therapy. Doctors can treat the symptoms of WNV Encephalitis; however, about 7% of people who be-come sick enough from the infection to be hospitalized die from it.

4. How is WNV spread?

Only adult mosquitoes that are infected with the virus spread WNV. The infection cannot be spread from person to person. The risk of getting WNV Encephalitis is greatest from late July through September. Use gloves or double plastic bags when handling dead animals, especially birds. If you notice unusual numbers of dead birds in your area, call your local board of health.

5. What can you do to protect yourself?

The only way to protect yourself is to keep mosquitoes from biting you.

Important Steps to follow:


  • Avoid outdoor activities between dusk and dawn when mosquito activity is greatest.
  • If you are outdoors during these times, wear long sleeved shirts and pants.
  • Use a 30-35% DEET containing mosquito repellant and follow the label directions.
  • Avoid using repellants with more than 10-15% DEET on children less than 3 years old.
  • Never use DEET on infants
  • Cream, stick, and lotion formulas are best.
  • Take special care to cover up the arms and legs of children playing out-doors.
  • When you bring a baby outdoors, cover the carriage or playpen with mosquito netting.
  • Fix any holes in your screens and make sure they are secure to windows and doors.


6. What can you do to reduce the number of mosquitoes around your home?


  • Get rid of any standing water that is available for mosquito breeding. They will breed in any puddle that lasts for more than four days.
  • Dispose of water collecting containers such as old tires, cans, and pots.
  • Empty water that has collected in birdbaths, wading pools and wheel-barrows.


The threat of WNV is a reminder that everyone should continue to take personal protection steps to avoid mosquito bites, and eliminate mosquito breeding grounds. Personal protection is the first line of defense against mosquitoes that can carry diseases such as WNV and is by far the most effective way of avoiding infection.