West Nile Virus: A Summertime Threat

July 3, 2007— -- With summer now in full swing, the kids are out of school and off on camping trips, beach excursions, picnics, bicycle rides and outdoor sporting events.

Most of us are familiar with the summertime dangers of sun exposure and recreational injuries, but few may know the true hazards of mosquito bites.

The vast majority of these bites cause a harmless, annoying itch that resolves in a few days. However, some mosquito bites could infect you with West Nile Virus -- a microorganism that could cause you or your child to develop fever, headache, body aches — or worse.

Do you know how to protect yourself?

West Nile Virus is a disease that spreads from the bite of infected mosquitoes to birds and humans. Horses, cats, dogs, rabbits, squirrels, bats and skunks can also be infected, albeit less often.

West Nile Virus was first discovered in 1937 in a feverish woman in Uganda, Africa. Over the decades it has slowly spread across the globe, and it made its U.S. debut in New York City in 1999.

Prior to this time, the infection was unknown in the United States; now, however, it has become common throughout the country, having been reported in all 48 mainland states and the District of Columbia.

Last year the virus was particularly active; although only 4,261 cases were officially reported, the Centers for Disease Control and Prevention (CDC) estimates that more than 43,000 West Nile infections occurred in the United States during 2006.

West Nile Virus can cause three different illnesses in humans. The first type, asymptomatic West Nile, occurs in 80 percent of people bitten by an infected mosquito and causes no symptoms at all and resolves on its own.

The second type of illness is called West Nile Fever. About 20 percent of people infected with the virus have this disease, which includes high fever, headache, body aches, nausea, vomiting and a rash on the abdomen and back. Symptoms start three to15 days after a mosquito bite and may last a few days to a few weeks.