Dealing with bug bites

(Republished with permission from the St. Louis Post-Dispatch. This article originally ran in the Healthy & Fit section on Monday, July 9, 2007)

By Dr. Julia Graves and Dr. Ann Martin

Almost every child will get a few bug bites this summer. While most bites are merely annoying, some can be more serious.

Mosquitoes

In the United States, mosquitoes are mainly just a nuisance. But they can spread diseases, such as the West Nile virus.

Mosquitoes are most active at dawn or dusk and near wetlands. Only female mosquitoes bite. Bites cause red, itchy welts that usually resolve after a day or two.

DEET (N,N-diethyl-meta-toluamide) is the most effective insect repellent available and works against mosquitoes, ticks and chiggers. It repels insects but does not kill them.

It is approved for use on children more than 2 months old.

It should be applied to exposed skin and clothing, avoiding the eyes, mouth and any sore or irritated skin.

Chiggers

Chiggers are tiny orange or light-red mites that are most active in spring and summer. They are commonly found in damp areas with abundant trees and scrubs. Larvae feed by attaching to human skin using their mouthparts. Itching and welts appear within hours and may last up to two weeks. Chiggers tend to attach to areas where clothing fits tightly, such as the ankles, waistline and armpits.

Humans elicit an immune reaction that causes chiggers to fall off or die within hours. Therefore, the welts themselves do not usually contain live chiggers.

Because chiggers do not burrow under the skin, bathing your child after he or she has been outdoors can easily remove chiggers.

Ticks

Although most tick bites are benign, ticks can cause disease by transmitting microorganisms or by secreting toxins and have been linked to a wide variety of diseases, including Lyme disease, Rocky Mountain spotted fever and tick paralysis.

Ticks are unable to fly or jump and typically reach humans by climbing onto vegetation or pets. They attach to skin using barbed mouthparts. There is often redness and swelling at the site of a bite. Ticks should be removed by grasping the tick near its head with tweezers and gently pulling back, taking care not to squeeze the tick. The tick should be saved in a sealed container in case identification is necessary.

Stinging insects

Stinging insects include bees, wasps, hornets, yellow jackets and fire ants.

Bees die after stinging because their barbed stingers are ripped off and left behind in the victim. Wasps, hornets and yellow jackets can sting multiple times.

At the site of a sting, pain, redness and swelling may develop, which may spread to involve a large area. These symptoms usually subside within hours to days. Cold compresses and acetaminophen may help alleviate discomfort.

Children with allergies to these insects may develop a potentially deadly reaction known as anaphylaxis. Symptoms usually start within 10 minutes after a sting and include swelling of the face, wheezing, difficulty talking or swallowing, dizziness and abdominal pain or nausea. If your child displays any of these symptoms after a sting, seek emergency medical treatment.

Spiders

Most spiders found in the United States are harmless. But bites from brown recluse spiders, which are common in Missouri, can be more serious.

The brown recluse spider is about an inch long and has a characteristic violin-shaped marking on its upper back. True to its name, the brown recluse likes to hide in undisturbed areas, such as basements, closets and attics. They are not aggressive and usually bite only when pressed up against human skin.

Their venom contains an enzyme that destroys tissue. Therefore, the site of the bite may blister, ulcerate or turn black.

If you think that your child has been bitten by a brown recluse spider, seek prompt medical attention. Brown recluse spider bites may occasionally be associated with anemia (low blood cells), blood clotting abnormalities, kidney failure and even death.

For more information, visit www.stlchildrens.org, or call the St. Louis Children’s Hospital Answer Line at 314-454-5437.

Dr. Julia Graves is a resident physician in dermatology at Washington University School of Medicine. Dr. Ann Martin is a dermatologist at St. Louis Children’s Hospital and assistant professor of internal medicine (dermatology) at Washington University School of Medicine.

Copyright 2007 St. Louis Post-Dispatch, Inc.