Facts
  • Very few spiders bite people, because of the inability to pierce the skin with their fangs.
  • The brown recluse and black widow have venom that is harmful to people.
  • Black Widows' venom is neurotoxic, affecting the human nervous system. It seldom causes death (mortality rate is less than 1%) since a small amount of poison is injected when it bites, but anyone bitten by a Black Widow spider should seek medical attention.
  • Brown Recluse venom is necrotic and causes damage to tissues surrounding the site of the bite.

 

Causes of Injury
  • Bites from a poisonous spider

 

Prevention
  • Avoid reaching under objects where a spider might hide such as logs, rocks, debris, caves, clothing, gloves and shoes.
  • If you are camping keep the tent zipped.
  • Wear shoes when walking around the campsite at night.
  • Use caution when handling and studying spiders.

 

Planning/Packing Guide
  • Bandana or elastic bandage for constricting band
  • Gloves
  • Camera for spider identification
  • Acetaminophen or Ibuprofen for pain

 

Symptoms
  • Black Widow
    • Bite looks like a pinprick
    • Slight swelling
    • Weakness
    • Pain
      • starts with dull cramping
      • becomes intense and spreads throughout the body
      • usually subsides in several hours
    • Anxiety
    • Painful breathing
    • Chills/fever
    • Headache
    • Dizziness
    • Nausea/vomiting
    • Abdominal pain
    • Muscle cramps/spasms
    • Swollen eyelids
    • Dilated pupils
    • Symptoms usually disappear in several days.
  • Brown Recluse
    • Possible sharp sting
    • Pain
      • often becomes severe
      • may develop within the first several hours or up to 6 to 8 hours after the bite
    • General feelings of discomfort
    • Malaise
    • Nausea
    • Sometimes intense itching
    • Sloughing off of the skin and formation of a blister in sever cases
    • Ulcer in the area of the bite
    • Reddish to purplish color in a bullseye patter to the skin area around bite
    • Chills or fever
    • Sweating may be occur
    • Skin blisters
    • Blackening of the local tissues
    • In severe cases the following can occur:
      • blood in urine
      • jaundice
      • kidney failure
      • seizures
      • coma

 

First Aid
  • RICE:
    • Rest - Keep area immobilized.
    • Ice - Apply ice or cold pack.
    • Compression - Apply light constricting band above the bite to slow venom spread.
    • Elevation - Keep site at heart level.
  • Clean the site with soap and water.
  • Give acetaminophen or ibuprofen for pain.
  • Seek medical attention since complications can occur. Alert ahead if possible.
  • Catch (or photograph) spider for positive identification at hospital.

 

Identification of Poisonous Species
  • Black Widow is shiny black with red hourglass marking on the abdomen.
    Females are about half an inch long and 1.5 inches when the legs are spread.
    Black Widow spiders live in all four deserts of the American Southwest.
  • Brown Recluse has long thin legs and is light brown colored
    They are about half an inch long with violin-shaped marking on the head and back.
    Oval shaped abdomen
    Six eyes in pairs

 

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