Experts expect the West Nile virus to appear in Idaho again with the arrival of warmer weather and mosquitoes. The first signs of the virus probably will show up in mid to late summer.
But the presence of West Nile virus is no reason to stop enjoying Idaho's great outdoors. Only a fraction of the mosquito population carries the virus, and only a few people who get bitten and infected get sick. Officials encourage people to take a few simple precautions against mosquito bites, such as wearing long sleeves and pants, using insect repellent that contains DEET and eliminating standing water around your home.
Most people bitten by an infected mosquito do not become ill, though some may experience a mild fever, headaches and body aches. Fewer than one percent of people infected with West Nile will suffer serious complication such as inflammation of the brain or paralysis. In severe cases, infection can lead to death.
The Centers for Disease Control and the U.S. Geological Survey report that in Idaho in 2005, West Nile virus showed up in 114 horses, 15 birds and in 13 humans. The human cases all were reported in August and September in southwestern Idaho-two each in Ada, Canyon, Elmore and Gooding counties; and one each in Owhyee, Twin Falls and Washington counties.
The 13 cases included 10 cases of West Nile fever and three cases of the more serious West Nile encephalitis or meningitis. No fatalities were reported.
The West Nile virus was discovered in New York in 1999 and spread rapidly across the country. It now is found in all 48 continental states. The virus showed up in Idaho at a commercial fish farm in the Hagerman valley in November 2003. One worker at the farm tested positive, making him the first person to acquire West Nile in Idaho.
Through 2004, only three people, seven birds and 22 horses tested positive for the virus in Idaho.
Dead birds-especially crows, jays, magpies, blackbirds, hawks and eagles-are the first clue that the virus has reached an area. The Idaho departments of Health and Welfare and Fish and Game have developed a surveillance protocol to track reports of dead birds.
Once West Nile is in an area, people need to learn to live with it. The best protection is to avoid mosquito bites. Simple tips for prevention include:
¥ Cover up exposed skin when outdoors
¥ Apply insect repellent containing DEET to your exposed skin and clothing
¥ Follow instructions on the product label, especially for children under 12
¥ Avoid outdoor activities at dawn and dusk when mosquitoes are most active
¥ Eliminate standing water around your home that may provide mosquitoes a place to breed
¥ Empty birdbaths and clean decorative ponds every 3 to 6 days
¥ Repair or install screens on your home
¥ If you have a horse, vaccinate it. One-third of horses infected by West Nile virus die
¥ Hunters should wear latex gloves when field dressing and handling wild game
¥ Cook meat thoroughly
¥ Report dead birds to your local Fish and Game office