Insects are discriminating creatures with their own favorite fragrances. Some prefer Obsession, some favor lighter scents like Giorgio, and some will bite anyone that happens to be near, no matter how they smell.

"We don't know why insects seem to prefer some individuals over others," says Dr. Barbara A. Muller, professor in the department of internal medicine at the University of Iowa College of Medicine and staff physician at UI Hospitals and Clinics. "We do know mosquitoes are attracted to warmth and human odors, including body sweat, by carbon dioxide given off during breathing.

"Be sensible to avoid being bitten or stung," Muller says. "Wear long sleeves and pants, socks and closed-toed shoes when you're in the woods. The smell of food attracts insects, so be careful when eating or drinking sweet beverages outdoors. Don't wear perfume, cologne, or bright-colored clothes." In addition, you can use a repellent containing deet, the active ingredient in most brand-name repellents, Muller says. "Deet will help protect you from bites or stings by flies, gnats, chiggers, ticks, and mosquitoes. However, deet doesn't work against yellow jackets, hornets or honeybees." Cover all exposed skin, but be careful to keep the repellent away from your eyes and mouth. "In hot, humid weather, you may need to apply the repellent every two hours."

Several people swear by home remedies for mosquito bites, including a paste made of three teaspoons of baking soda and one teaspoon of water to relieve itching, Muller says. "And Avon's Skin-So-Soft is a favorite insect repellant with many people."

The reason bug bites are so annoying is because flies, fleas, and mosquitoes actually sting their victims with a sharp stylus to inject saliva and chemicals to prevent blood clotting. Then they suck the blood.

"Your reaction to a bite depends on your sensitivity to the insect's saliva. Some people have no reaction at all, and some may have itching, bumps or redness that may be associated with fever or joint pain. Cool, wet compresses and oral antihistamines can help ease the pain."

Yellow jackets, hornets or honeybees sting with venom and may cause an allergic reaction that may include mild to moderate burning, itching, swelling and redness. "In .5% to 1.5% of stings, serious allergic reactions may occur leading to anaphylaxis," Muller says. Symptoms of a severe allergic response include local swelling that spreads from the sting site, body rash, hives, coughing, wheezing, shortness of breath or shock. "These reactions are life-threatening. It is extremely important to administer epinephrine intramuscularly if available and call 911 immediately."

People who spend a lot of time outdoors, including farmers and utility workers, and who have allergic diseases have a greater chance of developing an allergic reaction to insect stings. But severe allergic reactions to mosquitoes and flies are extremely rare.

If you have questions about insect repellents or insect stings, talk to your doctor.