West Nile Virus (WNV) is a member of the Japanese Encephalitis Virus group. It was first isolated in 1939 from a febrile woman in the West Nile district of what is known as Uganda - so it is known as the West Nile Virus. The virus is commonly found in humans and birds and other vertibrates such as horses.

Documented outbreaks of WNV have occurred since 1951, but outbreaks did not occur in the western hemisphere (i.e. United States) until 1999. In 1999, there was an outbreak in New York State and since then outbreaks have been occurring across the United States in a westerly fashion.

The peak incidence of cases of WNV occur in the late summer and early fall. WNV in humans is transmitted via a mosquito bite from an infected mosquito. Mosquitoes become infected by biting infected birds. Not all mosquitoes are infected. The public can help track the disease by reporting dead birds - especially crows, hawks, and blue jays - by calling the State Health Department at 1-877-PA-HEALTH.

People with compromised immune systems are also at increased risk.

Treatment is supportive. In other words, doctors treat the symptoms. There is no vaccine. Most people will recover fully. Approximately 25% of people infected with WNV will require Intensive Care Unit care and 10% will require mechanical ventilation.

To decrease the risk of developing WNV, we need to reduce the number of mosquitoes around our homes and neighborhoods. Mosquitoes lay their eggs in stagnant water around the home, so we need to eliminate sources of standing water. By eliminating places for mosquitoes to breed, we can go a long way toward preventing WNV. To accomplish this, try:

• Dispose of tin cans, plastic containers, ceramic pots, and other water-holding containers
• Install an outdoor-use fountain in bird baths to circulate water
• Pay special attention to discarded tires on your property - dispose of them or try using as planters, filled with dirt.
• Drill holes in the bottom of recycling containers and garbage cans that are left outdoors
• Clean clogged roof gutters

We also need to take normal steps to prevent insect bites. Wear shoes, socks, long pants, and long sleeves when you are outdoors for long periods or time or when mosquitoes are most active. Use insect repellent with 20% - 30% DEET. Also spray your clothing with insect repellent. Do not apply repellent to children less than two years old. When possible, avoid exposure, especially at dawn, dusk, and early evening during peak mosquito periods of April through October. Make sure you have tight-fitting screens over windows and doors to help keep mosquitoes from entering apartments and homes.