West Nile cases reported nearby

Friday, August 8, 2008

Recent cases of West Nile virus are hitting closer to Putnam County -- Hamilton County reported some cases of the mosquito-transmitted virus this week.

Along with news of the virus are tips on keeping from getting bitten by the nasty bloodsuckers. But for some people, it seems nothing they do helps prevent an attack from a mosquito.

A report by Jerry Butler, PhD and professor emeritus at the University of Florida said mosquitoes do exhibit blood-sucking preferences.

"One in 10 people are highly attractive to mosquitoes," he said. It is the female insect that bites. She isn't looking for dinner but rather needs human blood to develop fertile eggs."

So far, scientists have discovered that genetics account for 85 percent of our susceptibility to mosquito bites. They have identified certain elements of our body chemistry that, when found in excess on the skin's surface, make mosquitoes swarm closer.

"People with high concentrations of steroids or cholesterol on their skin surface attract mosquitoes," said Butler in an interview with Web site WebMD (www.webmd.com) "That doesn't necessarily mean that mosquitoes prey on people with higher overall levels of cholesterol. These people may simply be more efficient at processing cholesterol, the byproducts of which remain on the skin's surface."

Mosquitoes also target people who produce excess amounts of certain acids, such as uric acid. They can smell their dinner from an impressive distance of up to 50 meters.

"They are also attracted to people who emit large quantities of carbon dioxide," says entomologist John Edman, Phd from the Entomological Society of America.

"Larger people tend to give off more carbon dioxide, which is why mosquitoes generally prefer munching on adults and leave small children alone. Pregnant women are also at increased risk, as they produce a greater-than-normal amount of exhaled carbon dioxide. Additionally, movement and heat also attract the nasty critters," Edman said.

Even if your body chemistry doesn't attract mosquitoes, where you live or play might. These pests will fly up to 40 miles for a good meal.

While any water source is a potential breeding ground, they prefer stagnant water. If you want water on your property, forget about a pond and go for a babbling brook, say experts.

Mosquitoes have been around for 170 million years, and there are more than 175 known species in the U.S.

They aren't going anywhere.

You can do some things to minimize their impact. There are plenty of mosquito repellents available. DEET continues to be the chemical of choice in repelling the insect. It's been around since 1957, and most formulas contain between 10 and 30 percent of the chemical. Use on children under 2 years should only have concentrations of DEET of 10 percent or less.

Another repellent is one with lemon eucalyptus, sold under the Repel brand name. This product offers protection similar to low concentrations of DEET. It is safe only for children over three years.

Wearing repellent can protect you for about five hours, so be sure to re-apply if you are outside over that amount of time.

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