Chapter 18
Insect and Arthropod Bites and Stings
Lesson Objectives (1 of 2)
• Describe the bites of poisonous spiders, including
black widow spiders, brown recluse spiders, and
tarantulas, and explain how to manage such bites.
• Recognize a scorpion and its sting and know how
to manage such stings.
• Assess and treat tick bites and know that some
ticks can transmit Lyme disease to humans.
Lesson Objectives (2 of 2)
• Assess and manage mosquito bites.
• Identify lice and no how to eradicate a lice
infestation.
• Assess and treat insect stings and identify the
various types of insect repellents.
Spider Bites (1 of 8)
• Black widow spider
© photobar/ShutterStock, Inc.
Spider Bites (2 of 8)
• Black widow spider
– What to look for:
• A sharp, pinprick sensation
• Faint red bite marks
• Muscle stiffness and cramps affecting the
bitten limb and ascending to the abdomen
and thorax
• Headache, fever, chills, heavy sweating,
dizziness, nausea, vomiting, and severe
abdominal pain
Spider Bites (3 of 8)
• Black widow spider
– What to do:
• Catch the spider for identification.
• Clean the bite with soap and water.
• Use an ice pack on the bite to relieve pain.
• Administer pain medication orally.
• Check breathing.
• Seek medical attention immediately.
Spider Bites (4 of 8)
• Brown recluse spider
Courtesy of Kenneth Cramer, Monmouth College
Spider Bites (5 of 8)
• Brown recluse spider
– What to look for:
• Bite with bull’s-eye appearance and a blister
at the site with redness and swelling
• Local pain
• Fever, weakness, vomiting, joint pain, and a
rash
Spider Bites (6 of 8)
• Brown recluse spider
– What to do:
• Catch or kill the spider for identification.
• Clean the bite with soap and water.
• Use an ice pack on the bite to relieve pain.
• Administer pain medication orally.
• Seek medical attention promptly if large
areas of inflammation develop.
Spider Bites (7 of 8)
• Tarantula
© photobar/ShutterStock, Inc.
Spider Bites (8 of 8)
• Tarantula
– What to do:
• Clean the bite with soap and water.
• Relive pain with an ice pack.
• Evacuate if the species is known to
be dangerous.
Scorpion Stings (1 of 4)
© Kirubeshwaran/ShutterStock, Inc.
Scorpion Stings (2 of 4)
• What to look for:
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Instant local pain and burning
Difficulty swallowing
Slurred speech
Numbness and tingling
Scorpion Stings (3 of 4)
• What to look for:
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Occasional paralysis
Muscle spasms
Breathing difficulties
Jerking and twitching
Scorpion Stings (4 of 4)
• What to do:
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Check breathing.
Clean the bite with soap and water.
Apply an ice pack to relieve pain.
Evacuate as soon as possible.
Centipede Bites (1 of 2)
• Centipedes have small fangs and venom glands.
• Burning pain, swelling, and redness can last up
to 3 weeks.
Centipede Bites (2 of 2)
• What to do:
– Most bites will get better without treatment.
– Administer antihistamines by mouth.
– Apply hydrocortisone on the bite.
Tick Bites (1 of 7)
© Joao Estevao A. Freitas (jefras/ShutterStock, Inc.
Tick Bites (2 of 7)
• What to do:
– Difficult to remove
– Improper or partial removal can lead to local
infection.
– Use tweezers or a tick removal device to grab the
tick close the skin and pull steadily; or lift slightly
upward, and then pull parallel to the skin.
– If head remains embedded, remove with a
needle.
Tick Bites (3 of 7)
• What to do:
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Wash the bite with soap and water.
Apply an ice pack for pain.
Watch for signs of local infection.
Watch for symptoms of tick-borne illness.
Seek medical attention if symptoms appear.
Tick Bites (4 of 7)
• Lyme disease
– A potentially serious tick-borne infection
– Affects the joints, skin, heart, and nervous
system
– Transported by ticks from deer and mice
to humans
Tick Bites (5 of 7)
• Lyme disease
– What to look for: Early stages
• Distinctive rash
• Fatigue
• Fever
• Chills
• Weakness
• Headache
• Stiff neck
• Muscle or joint pain
Tick Bites (6 of 7)
• Lyme disease
– What to look for: Later stages
• One-sided paralysis
• Arthritis
• Meningitis
• Nerve damage
• Heart damage
Tick Bites (7 of 7)
• Lyme disease
– What to do:
• If symptoms appear within a month of a
tick bite, consult a doctor.
• Antibiotic treatment is usually curative.
Mosquito Bites
• Mosquitoes carry many diseases.
• Use an effective repellent and mosquito netting.
Lice (1 of 2)
© Phototake, Inc./Alamy Images
Lice (2 of 2)
• What to do:
– Treat with lice shampoo or lotion containing
permethrin, pyrethrins with piperonyl butoxide,
or lindane.
– Wash clothes, sleeping bags, pillow cases, or
other bedding in soap and hot water.
– Do not share clothes or hairbrushes.
Insect Stings (1 of 7)
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Honeybee
Bumblebee
Yellow jacket
Wasp
Fire ant
Insect Stings (2 of 7)
• What to look for:
– Stinger may be visible.
– The sooner symptoms develop, the more
serious the reaction.
Insect Stings (3 of 7)
• What to look for:
– Local reactions
• Brief pain
• Redness
• Swelling
• Itching
• Heat
Insect Stings (4 of 7)
• What to look for:
– Generalized reactions
• Diffuse skin redness
• Hives
• Swelling of lips or tongue
• Wheezing
• Abdominal cramps
• Diarrhea
Insect Stings (5 of 7)
• What to look for:
– Life-threatening reactions:
• Inability to breath due to swelling of
the air passages and throat
• Bluish or gray skin color
• Seizures
• Unconsciousness
Insect Stings (6 of 7)
• What to do:
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Scrape the stinger and venom sac off the skin.
Wash the sting with soap and water.
Apply cold to the site for 15 to 20 minutes.
Give a mild analgesic.
Use hydrocortisone and antihistamines to
reduce local symptoms.
Insect Stings (7 of 7)
• What to do:
– Use a paste of baking soda and water to
absorb venom and relieve pain.
– Observe for at least 60 minutes for serious
allergic reaction.
– If hives or redness and swelling occur with
difficulty breathing, administer epinephrine.
Insect Repellents
• Natural repellents (citronella and lemon eucalyptus)
• Synthetic repellents (DEET and dimethylphthalate)
• Insecticides (permethrin, deltamethrin, and
alphamethrin)