Dr. Greene, My son (along with several of his classmates) was recently stung by bees. The sting was on his foot, and the next morning, the entire foot was swollen. Is this serious? How do you treat bee stings? What insect repellents work the best at preventing them?

Bee stings have been a nuisance long enough to have appeared in prehistoric cave paintings in Spain. Bee stings are part of our collective memory and they are part of our individual memories as well. While many moments of childhood come and go, the surprise, the pain, and the tears etch bee stings into images that we can recall even in old age, when our short-term memory begins to fade.

Bees have a highly developed social culture. The many species of bees have an important role in our environment. Most species of bees are clearly beneficial to humans. They are also the only insects that make food consumed by humans. But their stings hurt... and can be lethal.

Typically, bees are not aggressive creatures. Their stingers are for defense, not attack. Honeybees die when they sting. Preventing stings is best for all concerned. Traditional insect repellents are of no use in preventing bee stings. What does work?

Effective prevention means not attracting bees and not frightening them if they are present. Prevention techniques are especially important in the fall, when most stings occur. It takes 2 million visits to flowers to make one pound of honey. In the autumn, as flowers disappear, bees search more widely for food and take more risks.

Today, I spent some time with a beekeeper who was standing inside a screened cage full of honeybees. The bees rested on his bare face and arms as he described how to avoid stings. Flowers attract bees by their fragrant aroma, their bright colors, and their sweet taste.

To avoid attracting bees, try the following:

• Avoid fragrances, including hair spray, scented soaps, lotions, and oils. Bees usually approach children with a sweet scent.
• Don't wear brightly colored clothing, particularly floral patterns, i.e. don't look like a flower patch. Bees also see in the ultraviolet range. If the pattern lights up under black light, it is particularly interesting to bees.
• Be very careful with food. Cans of soda are notorious: Bees climb in unobserved, and are frightened into stinging when the child drinks. Something as small as a forgotten raspberry jam stain on a sweater can be a problem.

If a bee does land, take steps to avoid frightening it:

• Hold still. Tell kids to pretend they're statues. Rapid movement startles the bee and encourages stinging.
• Try blowing gently on the bee. This can encourage it to move on while not startling it.
• Wear shoes. Bees will of course be frightened if you step on or near them. Shoes don't make them less frightened, but they do protect feet from frightened bees.
• Wear long pants when you know you are going to be in an area that is likely to have bees in it, such as a field.
• Wear a hat. Furry animals steal honey from bees. Bees are in a heightened state of readiness when they are close to hair or fur. They have been proven to have a lower threshold for stinging people with hats. The beekeeper today was wearing a pastel baseball cap.

The bee's stinger is barbed. In the act of stinging, the stinger is torn from the bee, along with the venom-filled poison sac and attached muscles. The barbs continue to work the stinger deeper into the flesh for several minutes, while venom continues to be injected.