Insect Bites

Reviewed/Revised Sep 2024
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Many different types of insects (bugs) can bite you. Most insect bites itch, but the bites themselves aren't serious. The main problem with insect bites is that:

Common biting insects in the United States are:

  • Flies, including sand, horse, deer, black, and stable flies

  • Mosquitoes

  • Fleas

  • Lice

  • Bedbugs

  • Kissing bugs

  • Some water bugs

None of these insects has venom (poison).

Ticks, spiders, and mites belong to a different group and aren't insects.

What are the symptoms of an insect bite?

Most bites result in:

  • A small, red, itchy bump

Sometimes, you might have:

  • A large sore (ulcer) that is swollen and painful

  • Symptoms of infection, such as redness and swelling around the bite

  • Very rarely, symptoms of an allergic reaction, such as a rash, hives, or trouble breathing

Fleas can sometimes cause an allergic reaction even if you're not bitten.

What diseases are spread by insect bites?

Different types of insects spread different diseases. Not every insect carries disease, even in areas where many insects do.

Some of the diseases spread through insect bites are:

How are insect bites treated?

If you think you're having an allergic reaction, go to the hospital right away.

Doctors will tell you to:

  • Clean the bite

  • Apply a medicated cream to the bite to lessen your pain, itching, and swelling

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