Deadly Spiders in United States

While all insects are creepy and crawly, there is something about eight legs, multiple eyes and hairy abdomens that make spiders particularly frightening. Not only are spiders spooky enough to send you screaming away in terror, but they will also bite if provoked. Most spider bites, while painful, are harmless. Certain species, however, can be dangerous and downright deadly. There are two dangerous spider species in the United States.

Black Widow

Right out of a horror film, black widow spiders are dark black with long, slender legs and bright red hourglass markings on their backs. These spiders are often found hiding in dark, seldom disturbed corners like sheds, woodpiles, basements and underneath furniture. They spin erratic, silken webs in which they hang upside down, waiting for their next meal. While non-aggressive, black widows will bite humans if threatened. Black widows use venom to paralyze their prey and, if bitten, this venom can be fatal to humans (particularly children and the elderly). Severe reactions are rare but possible, and thus all black widow spider bites should be treated as an emergency.

Possible complications from a black widow spider bite:

  • Pain and swelling at the location of the bite, as well as redness and itchiness. Pain can range from mild to severe and may spread well beyond the bite, affecting the abdomen, back and chest.
  • Severe stomach pain and cramping.
  • Chills, nausea and/or abnormally increased sweating.
  • High resting heart rate and muscle spasms.

If you suspect that you or a loved one has been bitten by a black widow, it is important to seek medical treatment as soon as possible, especially if the individual is a child or elderly. There is an antivenom available for black widow bites that effectively treats serious bites.

Brown Recluse

Also known as “fiddle-back spiders,” brown recluse spiders have a distinctive violin or fiddle shape on their abdomens. These spiders prefer dark, secluded areas and are often found in outdoor areas, garages, basements or hidden under furniture. If you see what you suspect is a brown recluse spider in your home we recommend you call a professional spider extermination company  as these spiders propagate rapidly. Females can lay egg sacs containing 40-50 eggs up to 5 times in a life span and infestations are common. While brown recluse spiders are not particularly aggressive, they will bite when threatened. Bites often occur when someone unknowingly puts on a shoe, work gloves or clothing that contains a hidden brown recluse.

The bite of a brown recluse is very painful. Most bites heal within a week, but severe complications are possible. Brown recluse venom is hemotoxic and can destroy red blood cells and skin tissue.

Possible complications from a brown recluse bite include:

  • Deep ulcer formation, with the center of the bite turning blue or purple and then breaking open into a large, oozing sore. Necrosis, or tissue death, is common and results in a wound that takes a long time to heal and causes excessive scarring.
  • Fever, chills and abnormally increased sweating.
  • Severe pain and abdominal cramping.
  • Muscle and joint pain.
  • Nausea and vomiting.
  • Rarely, fatal.

Severe complications are more common in children, the elderly and those with weakened immune systems. If complications are present, it is recommended to seek medical assistance as soon as possible.

Another spider worth mentioning, although it is rarely dangerous, is the wolf spider. This large, brown spider is sometimes mistaken for the brown recluse. A wolf spider bite is not venomous, but it is extremely painful. In most cases, these bites heal quickly, but some individuals may develop an allergic reaction. The wolf spider bite can be compared to a bee or wasp sting – painful, but not particularly dangerous unless the bitten or stung individual is susceptible to allergic reactions.

Like many other pests, the most harm spiders can cause humans is a heart-stopping moment of fear. Many common house spiders are not venomous, but their bites are certainly painful. However, identifying pests is something that only a trained professional can do. As black widow and brown recluse spiders are common throughout the United States, it is always better to be on the safe side when encountering a spider. If you see a spider or suspect an infestation, feel free to call Saela, your local pest control company. We have Associate Certified Entomologists on staff that can identify any pest and our spider extermination program can handle even the most dangerous eight-legged insects.