OverviewSpider bites are usually harmless, and spiders don't usually bite unless threatened. Show Spider bites can cause redness, pain and swelling, or you might not notice them at all. Many other bug bites and skin sores cause redness, pain and swelling. So unless you actually saw a spider bite you, it's difficult to be certain that your wound was caused by a spider. Worldwide only a few species of spiders have fangs long enough to penetrate human skin and venom strong enough to hurt humans. Among these are widow spiders, with about 30 species, and recluse spiders, with more than 140 species worldwide. SymptomsTypically, a spider bite looks like any other bug bite — a red, inflamed, sometimes itchy or painful bump on your skin — and may even go unnoticed. Harmless spider bites usually don't produce any other symptoms. Many skin sores look the same but have other causes, such as a bacterial infection. Bites from some spiders, such as widow spiders and recluse spiders, might cause serious signs and symptoms. Widow spider bitesSigns and symptoms of a widow spider bite can include:
Symptoms can last 1 to 3 days. Recluse spider bitesSigns and symptoms of a recluse spider bite can include:
When to see a doctorSeek medical care immediately if:
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clicking on the unsubscribe link in the e-mail. CausesSevere spider bite symptoms occur as a result of the venom that the spider injects. Symptom severity depends on the type of spider, the amount of venom injected and how sensitive your body is to the venom. Risk factorsRisk factors for spider bites include living in areas where spiders live and disturbing their natural habitat. Widow spiders and recluse spiders like warm climates and dark, dry places. Widow spider habitatWidow spiders can be found throughout the United States, except Alaska, and are more common in the rural South. They're also found in Europe. They are more active in the warmer months and prefer to live in:
Recluse spider habitatRecluse spiders are found most commonly in the southern half of the United States and in South America, where they are known as brown spiders. These spiders are so named because they like to hide away in undisturbed areas. They are most active in the warmer months. Indoors, they prefer to live:
Sometimes they get mixed up in bed linens and clothing, causing many bites to occur in the early morning. Outside, they seek out dry, dark, quiet spots, such as under rocks or in tree stumps. ComplicationsRarely, a bite from a widow spider or recluse spider is deadly, particularly in small children. A severe wound from a recluse spider can take weeks or months to heal and leaves large scars. PreventionSpiders usually bite only in defense, when being trapped between your skin and another object. To prevent spider bites:
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