Spider Bites, Symptoms, Causes and Treatment

More than 45,000 spider species have been identified globally, of which less than 30 have been classified dangerous. This accounts for less than 1% harmful spiders worldwide, so humans are safe from the majority of them. The severity of the poison the dangerous ones carry vary from species to species. The panels below show four common dangerous ones that are widely distributed.

Spider Bites, Symptoms, Causes and Treatment
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The Brown Recluse or Violin Spider

This spider is reddish brown with violin-shaped dark marking in the chest area. They are usually between 6 and 20 mm. The brown recluse is found in the USA and other parts of the world, including West Africa. They live in quite places such as attics and sheds. They are usually not aggressive but will bite when threatened. The bitten effect is initially painless but over a course of about 8 hours, a target lesion or bruise occurs in the area and enlarge progressively. This occurs as a result of introducing poison (venom) through its long, sharp teeth called fangs into the bitten area of the skin.  If not treated soon, it can damage the surrounding tissue, causing fever, headache, and chills. In addition, there could be a sharp pain like bee-sting, body aches, nausea, rashes and stomach upset.

The Tarantula or Baboon Spider

The Tarantulas are rust brown to orange colored spiders, also called baboon spider in Africa. They are about 11.4 to 28 cm in length. They are nocturnal spiders which dig burrows underneath stones and live there, patiently awaiting their prey. Their venoms are neurotoxic, which means that when they bite, the poison affects the nervous system and can damage it with time. Their bites produce sharp pain and remain itchy for about 5 days. The victim may vomit and have difficulties in walking.

The Black Widow Spider

These spiders are normally shiny black in appearance, with hourglass markings (contractions) on their abdomen which come in different colors, ranging from yellowish through orange to red.  They are about 12.7 to 38 mm in length. They live in loft or storage places and sheds. They are considered the most poisonous in North America, with venom stronger than what will be found in most dangerous snakes. The fangs (long, sharp teeth) are long so they can penetrate deep into the skin upon biting to discharge the strong poison.  This can cause severe abdominal pain, weakness, muscle rigidity and excessive sweating.

The Huntsman or Rain Spider

These spiders are brown in color and may have stripes. They are very widely distributed. They appear somewhat very terrifying but in reality, they are not aggressive. They are about 25-30 mm in length, with smooth and plump bodies. They prefer to live in forests and shafts. They hunt at night and hide in the daytime. They are normally found in homes at summertime. They are called rain spiders because, in certain parts of Africa, they are more visible and become more active before and after rainfall. When they bite, the victims experience swelling, pain in the bitten area and headache. In addition, nausea and rapid heartbeat have been reported. Their venoms are known to be relatively weak so when they bite, the victim can overcome the effects between 5-7 days.

What are my treatment options for a dangerous spider bite?

  • Keep the bite area clean to avoid infection by using mild soap and water and wiping with a clean towel or cloth.
  • Reduce pain and swelling by applying an ice pack wrapped in a small
  • If a leg or an arm area was bitten by the spider, elevate it to avoid edema (swollen or inflammation from the injury).
  • Apply antibiotic ointment in the area if noticed the wound is becoming infected.
  • If experiencing pains, take over-the-counter pain relievers such as Advil or Tylenol.
  • Some bites can produce skin lesions and allergic reactions such as itching and inflammation. If this occurred antihistamine ointment like Benadryl can be applied to the wounded area.
  • If the victim’s tetanus shot is more than 5 years old, he may need a booster.

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  2. http://www.outdoorphoto.community/gallery/showphoto.php?photo=6615
  3. http://www.outdoorlife.com/photos/gallery/survival/2011/10/10-most-dangerous-spiders-world/?image=3
  4. http://www.planetdeadly.com/animals/most-dangerous-spider