West Nile Virus
West Nile virus is a virus commonly found in Africa, West Asia and the Middle East. It is not known how long it has been in the United States, but the Centers for Disease Control and Prevention (CDC) believe the virus probably has been in the eastern United States since early summer 1999.
It is closely related to St. Louis encephalitis virus found in the United States. The virus can infect humans, birds, mosquitoes, horses, and some other animals.
Below is information from the CDC regarding the West Nile Virus.
|Symptoms of West Nile Virus
| Most people infected with West Nile virus will not have any signs of illness. Twenty percent of people who become infected will have mild symptoms such as fever, headache, body aches, and occasionally a skin rash on the trunk of the body and swollen lymph glands.
The symptoms of severe infection (West Nile neuroinvasive disease) include headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis. Only about one out of 150 people infected with West Nile virus will develop this more severe form of the disease.
The incubation period of West Nile virus in humans is three to 14 days. Symptoms of mild disease may last a few days. Symptoms of severe disease may last several weeks, although neurological effects may be permanent. Rarely, death can occur.
People older than 50 have the highest risk of severe disease, and people with weakened immune systems are at an increased risk for West Nile virus.
Fewer than 1 percent of those bitten by infected mosquitoes become severely ill. If you have the symptoms mentioned in this fact sheet, contact your doctor immediately.
Preventing West Nile Virus
Preventing mosquito bites is the best way to avoid becoming infected with the West Nile virus. Remember the “Four Ds” of DEET, Dress, Dusk and Dawn, and Drain:
1. Apply insect repellent that contains DEET (N, N-diethyl-m-toluamide), picaridin, or oil of lemon eucalyptus. Spray exposed skin and clothing with repellent. Another option is to use permethrin, which should be applied only to clothing. Be sure to read label instructions on any repellent.
2. Dress in long sleeves and long pants when you are outside.
3. Stay indoors at dusk and dawn, times when infected mosquitoes are most active.
4. Drain standing water in your backyard and neighborhood; old tires, flowerpots, and clogged rain gutters are mosquito-breeding sites.
West Nile Virus Treatment/Vaccine
There is no specific treatment for West Nile virus infection. In severe cases, intensive supportive therapies are indicated, such as intravenous fluids and medicine to control fever or pain. Antibiotics may be given for any secondary bacterial infection.
Currently there is no vaccine for West Nile virus, but several companies are working toward developing a vaccine.