The 10 Most Dangerous Bugs You Need to Avoid

Watch out for these bugs once you start venturing out in the warmer weather

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Bugs are everywhere, and while most are harmless or even helpful, a few can pose serious threats to your health and safety. Whether hiking in the woods or simply spending time in your backyard, it’s important to know which bugs to avoid and why.

Ian Williams, a board-certified entomologist, highlights the steps you should take if you encounter a dangerous bug. “If you think you’ve spotted something dangerous in your home, quick action is needed to keep you and your family safe. If the insect is potentially harmful or venomous, avoid disturbing it – you must seek professional support for stinging pests like wasps, hornets or yellow jackets,” he says. To help keep dangerous bugs out of your home in the first place, Williams recommends keeping your home and yard tidy, sealing any cracks or crevices in your home’s exterior and managing interior moisture levels.

In this article we will highlight the 10 most dangerous bugs you might encounter, what makes them a threat and how to protect yourself.

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spider
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Black Widow Spider

Roughly the size of a paper clip and with the most dangerous venom 15 times stronger than a rattlesnake’s, this black spider can be spotted by the red markings on its belly.

The red markings are in the shape of an hourglass. Black widow spiders can live for 1-3 years in the wild and are often found alone.

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tarantula
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Tarantula Spider

With a lifespan of nearly 30 years, tarantulas can grow to almost the size of a personal pizza. Most dangerous tarantulas are afraid of large predators, but if provoked – watch out! Though their venom isn’t deadly, it’s unpleasant and can cause rashes and pain at the bite point.

3 / 10
bee
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Africanized Bee

Mostly found in the Southern and Southwestern portions of the United States, Africanized honeybees often travel in swarms to find a new hive. Most do not randomly attack people or animals unless they feel their new hive is in danger. If you see a swarm of bees or are near a hive, it’s important to move away from the area quickly.

4 / 10
mosquito
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Mosquitoes

Throughout the world, more people are killed by mosquito-borne illness than any other factor. In the United States, mosquitoes can spread different types of encephalitis and transmit heartworms to domestic animals like dogs and cats.

5 / 10
ant
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Red Fire Ants

About 1/2-in. long and brought accidentally by ship from South America, the red fire ant is a robust type of ant that can sting. Found on golf courses, at picnic grounds and at playgrounds, red fire ants are very common.

6 / 10
wasp
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Wasps

Wasps usually have a slender, shiny body but they can often look like honeybees. Unlike honeybees, when wasps sting they do not lose their stinger, allowing them to sting repeatedly.

7 / 10
brown spider
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Brown Recluse Spider

Native to the Midwestern and Southern United States, brown recluse spiders can be deadly to children under the age of 7. Displaying a violin-like shape on their back, these spiders can range in color from brownish-tan to yellow-tan. Most dangerous brown recluse spiders only bite when provoked.

8 / 10
Scorpions
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Scorpions

With a crab-like appearance, scorpions are predatory and often come out at night. Scorpions like warm, dry climates and are usually found in deserts.

Take precautions when hiking and camping by keeping shoes, blankets and towels secured indoors. Stings can feel like a honeybee sting with mild swelling or a rash, or may be more serious.

9 / 10
Ticks
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Ticks

Ticks can be very small and some can carry Lyme disease. Found throughout North America, ticks can attach to exposed skin. After spending time outdoors, it is essential to do a full-body check and remove any ticks right away. Removing a Lyme disease-carrying deer tick within 36 hours can reduce the risk of infection.

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Centipedes Millipedes
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Centipedes and Millipedes

Though not poisonous, millipedes secrete venom that can cause allergic reactions in some people. Centipedes also have venom that is not deadly but can be toxic to those allergic to insect venom. Both centipedes and millipedes are wormlike creatures.

FAQ

How can I tell if a bug is dangerous or just a nuisance?

While it is difficult to tell if a bug is dangerous just by looking at it, there are some telltale signs. Dangerous bugs can have bright, bold colors, large pincers or stingers, and may act aggressively when threatened. But bugs that carry hazardous diseases might not have these traits. The best defense is to become familiar with the dangerous bugs in your region so you can be prepared.

Are DIY pest sprays safe and effective?

DIY pest sprays are safe because they are meant for homeowner use and most can be effective at controlling bug populations when used correctly.

About the Expert

  • Ian Williams is a board-certified entomologist who specializes in urban entomology and is a technical services manager for Rollins Inc.