With the recent announcement of West Nile Virus in an eastern Oregon bird, you may be wondering about West Nile Virus, and what you can do to prevent it.

The Basics
The West Nile virus belongs to a group of viruses known as flaviviruses, that are transmitted to humans though insect bites, in most cases mosquitoes. West Nile Virus is commonly found in Africa, West Asia, Europe, and the Middle East, with an increasing number of cases in North America. West Nile virus occurs in late summer and early fall in temperate zones, such as Oregon.

According to the Centers for Disease Control and Prevention (CDC), West Nile virus infection in humans is still a rare occurrence. Though there has been no reported human infected in Oregon to date, the recent diagnosis of the virus in a dead crow in Vale, reminds us that we need to be aware of and take some basic precautions to prevent infection.

Transmission
West Nile Virus is spread to people when a mosquito feeds on an infected bird and then bites a human. Oregon State Epidemiologist, Dr. Mel Kohn, tells us that birds cannot transmit the disease directly to humans, nor can it be transmitted through person-to-person contact.

Signs and Symptoms

Mild Cases
Most people infected with West Nile virus experience only mild, flu-like symptoms that last a few days. Symptoms usually appear within 3 to 14 days of infection.

Symptoms may include:

• fever
• headache
• body aches
• skin rash on trunk of body
• swollen lymph glands

Severe Cases
The virus, however, can cause life-threatening illnesses such as encephalitis (inflammation of the brain), meningitis (inflammation of the lining of the brain and spinal cord), or meningoencephalitis (inflammation of the brain and its surrounding membrane). The more severe form of the West Nile virus (West Nile encephalitis, West Nile meningitis, or West Nile meningoencephalitis), that is present in one out of 150 cases, occurs when the virus crosses the blood-brain barrier.

Symptoms of West Nile encephalitis, West Nile meningitis, or West Nile meningoencephalitis may include:

• headache
• high fever
• neck stiffness
• stupor (a state of impaired consciousness, extreme lethargy, and reduced reactivity to external stimuli)
• disorientation
• coma
• tremors
• convulsions
• muscle weakness
• paralysis

Treatment
There is no specific treatment for West Nile virus-related diseases. Treatment will be determined by your physician based on your individual factors including age, overall health, and the extent of the disease. If a person develops the more severe form of the disease, West Nile encephalitis or meningitis, treatment may include more intensive supportive therapy, such as hospitalization, intravenous fluids and respiratory support (ventilator).

Currently, there is no vaccine available to prevent West Nile virus, so here are some basic steps, recommended by the CDC, that you can take to greatly reduce your chance of becoming infected.

Basic Steps

• Apply insect repellent containing DEET (N,N-diethyl-meta-toluamide) when you are outdoors. (If you spray your clothing, there is no need to spray repellent containing DEET on the skin under your clothing.) Follow label directions when using any repellant and use caution when applying to children.
• When possible, wear long-sleeved shirts and long pants treated with repellents containing permethrin or DEET since mosquitoes may bite through thin clothing. (Do not directly apply repellents containing permethrin to exposed skin.)
• Consider staying indoors at dawn, dusk, and in the early evening, as these are peak hours for mosquito bites, especially those mosquitoes that carry the West Nile virus.
• Limit the number of places available for mosquitoes to lay their eggs by eliminating standing water sources from around your home.
• Ensure that all doors and windows have screens that fit tightly and repair or replace screens that have tears or holes.