West Nile Virus is a type of Encephalitis. Encephalitis is an inflammation of the brain, sometimes caused by viruses and bacteria. West Nile is one of four mosquito-borne viruses found in Louisiana, which can cause such an infection. The others are LaCrosse, California and Eastern equine encephalitis. It is also closely related to the St. Louis encephalitis virus found in the United States. The incubation period in humans for West Nile encephalitis is usually 3 to 15 days. There is no vaccine against West Nile encephalitis. Remember, mosquitoes develop only in water, and water standing just a few days can produce a crop of mosquitoes.

While Louisiana has experienced the largest outbreak of West Nile Virus in U.S. History, the actual risk of contracting a serious illness after West Nile virus infection is slim. Only 1 in 5 people infected will develop any symptoms at all, while 1 in 150 infected individuals will suffer more serious complications. Individuals over 50 years of age and people with weak immune systems tend to be most prone to the West Nile virus infection. Fatality rates among those with severe illness due to West Nile virus range from 3% to 15%. Less than 1% of persons infected with West Nile virus will develop a serious illness.

West Nile encephalitis is NOT transmitted from person-to-person. Infected mosquitoes are the primary source for West Nile virus. In southern climates, where temperatures are milder, West Nile virus can be transmitted year round. Mosquitoes become infected when they feed on infected birds. They transmit the virus to humans and animals, while biting to take blood. Following transmission by an infected mosquito, West Nile virus multiplies in the person’s blood system and crosses the blood-brain barrier and enters the brain. The virus interferes with a normal central nervous system functioning and causes inflammation of brain tissue.

The mosquito-borne disease can cause mild flu-like symptoms and more rarely encephalitis, fever, headache, and body aches, occasionally with skin rash and swollen lymph glands. More severe infection may be marked by headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, paralysis, and rarely, death. If you develop a fever with a stiff neck, headache or confusion, call your doctor to determine if further evaluation is needed.

1. Stay indoors at dawn, dusk & early evening.
2. Wear long-sleeved shirts and pants outdoors.
3. Apply insect repellent sparingly to exposed skin and thin clothing. An effective repellent will contain 35% DEET. DEET in high concentrations provides no additional protection.
4. Repellents may irritate the eyes and mouth, so avoid applying repellent to your child’s hands. (NOTE: Children should not be exposed to insect repellent containing 10% DEET or more). Whenever you use an insecticide or insect repellent, be sure to read and follow instructions as printed on the product.
5. Install or repair windows and door screens, so that mosquitoes cannot get indoors.
6. Note: Vitamin B and “ultrasonic” devices are not effective in prevention mosquito bites.
7. Empty, remove, cover or turn upside down any receptacle that is outdoors that could collect water, such as children’s toys, old bottles, tin cans, flower pots, birdbaths, etc. since any standing water can serve as a breeding ground for mosquitoes.
8. Discard old tires or store them indoors.
9. Screen rain barrels and openings to water tanks or cisterns.
10. Change water and scrub vases holding flowers or cuttings twice each week – or grow cuttings in sand.
11. Repair leaky plumbing and outside facets.
12. Connect open waste-water drains to a sewage system, or construct separate pump or leach lines.
13. Clean clogged roof gutters and drain flat roofs.
14. Fill holes in trees with sand or mortar, or drain or spray them as needed.
15. Stock ornamental ponds with mosquito eating fish.
16. Fill or drain low areas on your property that hold water for longer than 4-7 days.
17. Wash all skin and clothing with soap and water when returning indoors to remove insect repellent.
18. Do not spray repellent in enclosed areas.
19. Spray repellent on your hands and then apply to your face.
20. Do not use repellent under clothing.
21. Do not apply repellent over cuts, wounds, sunburn, or irritated skin.
22. Avoid perfumes and colognes when outdoors for extended periods of time.