Topic Overview

Many insects, such as the following, cause mild reactions:

• Bedbugs.
• Kissing bugs.
• Chiggers.
• Fleas.
• Flies.
• Mites.
• Mosquitoes.
• Nonpoisonous spiders.
• Ticks.
• Scabies.
• Lice. For more information on lice, see the topic Body Lice, Head Lice, or Pubic Lice.

Some insects are more likely than others to cause allergic or toxic reactions.

• A bee leaves its stinger behind and then dies after stinging. Africanized honeybees, the so-called killer bees, are more aggressive than common honeybees and often attack together in great numbers. Reaction to bee stings can range from minor skin swelling and redness to a serious allergic reaction.
• Wasps, including hornets and yellow jackets, can sting over and over. Yellow jackets cause the greatest number of allergic reactions.
• A fire ant attaches to a person by biting with its jaws. Then, pivoting its head, it stings from its abdomen in a circular pattern at multiple sites.

Bites and stings are more serious if you develop one or more of the following conditions after an insect or spider bite or sting:

• A severe allergic reaction (anaphylaxis)
• A toxic reaction
• A large skin reaction with swelling and redness that spreads away from the site of the bite or sting. It may be as large as swelling across two major joints, such as from the elbow to the shoulder.
• Signs of a skin infection
• Serum sickness