If You Live in These States, Watch Out for This Venomous Spider

No one is ever excited about stumbling on a spider in their home. Thankfully, most of the spiders you come across in this case—American house spiders, wolf spiders, and daddy longlegs, among others—are harmless and keep other pests away. In fact, if you notice a lack of roaches, mosquitos, or flies in your home, you may have a house spider to thank. But that doesn't mean that all spiders are benign, and there are a few species in the U.S. you'll want to avoid. If you live in some states, you may need to watch out for one venomous spider in particular: the brown recluse.

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Brown recluse spiders are one of only two venomous spiders in the U.S., according to the National Institute for Occupational Safety and Health (NIOSH). This spider, also known as the violin spider, is brown with a dark violin-shaped marking on its head. Unlike most spiders, the brown recluse has only six eyes instead of eight.

According to the NIOSH, these spiders prefer secluded areas outdoors underneath structures or in piles of rocks or leaves. But if they do end up in your home, "they may be found in dark closets, shoes, or attics." On the plus side, these spiders are not naturally aggressive, per WebMD. They prefer to be left alone—hence the name—but they will bite you if they end up feeling trapped. And a brown recluse spider can do real damage. According to WebMD, this spider produces harmful venom.

If bitten, you'll likely develop a painful sore at the site, although the bite might not hurt or even leave a mark at first. Other symptoms can develop within the a day or two, such as pain or redness at the site of the bite, purple skin, fever, chills, nausea, joint pain, weakness, trouble breathing, and in rare cases, seizures or coma.

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You should see a doctor right away if you notice any of these symptoms. WebMD says that around 10 percent of brown recluse bites can cause ulcers or blisters that are so damaging to the skin, they require a doctor's care—especially if you develop an infection, which will require antibiotics. Some of their bites may also have tetanus spores, so you might need a tetanus shot after being bitten.

"The venom actually contains the enzyme that breaks down the cells of the human body," Rajani Katta, MD, a dermatologist and professor at both the Baylor College of Medicine and the McGovern Medical School at the University of Texas Houston, told U.S. News & World Report. "After that happens, your body has its own defense system that springs into action to try to contain that injury. Sometimes, if you get enough of that dose of venom, you start to get more breakdown. And the more breakdown in your cells that occurs, the higher the chance of scarring."

Recently, a 19-year-old British tourist had to get at least two fingers amputated after being bitten by a brown recluse spider in Ibiza, Spain. But in the U.S., this venomous spider only lives in a limited area. Outside of these parts of the country, "it is highly unlikely that you have a recluse spider," per experts in the entomology department at the University of California, Riverside. Read on to find out if you could happen upon a brown recluse spider in your state.

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