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Chapter 19

Insect and Arthropod Bites and Stings

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Insect Stings�(1 of 2)

Honeybees
Bumblebees
Yellow jackets
Hornets
Wasps
Fire ants

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Insect Stings�(2 of 2)

These insects account for more deaths and illnesses each year than all other venomous animals combined.

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Honeybees

Have barbed stingers
Die after the sting
Some venom remains in the stinger embedded in the person’s skin.

This venom worsens the person’s reaction.

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Wasps, Yellow Jackets, Hornets, Bumblebees, and Fire Ants

Stingers do not embed in person.
Can sting multiple times.
Most do not die after stinging.

Courtesy of Scott Bauer/USDA

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Reactions to Insect Stings

Reactions generally occur within a few minutes to 1 hour after the sting. The sooner symptoms develop, the more serious the reaction will be.

Courtesy of Daniel Wojcik/USDA.

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Multiple Insect Stings

Five hundred stings will usually kill even people who are not allergic to stinging insects.
Massive numbers of stings are rare.
Africanized bees (killer bees) are aggressive and more likely to be involved in multiple stings

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Insect Stings: What to Look For

Usual reactions:

Instant pain, redness, itching

Worrisome reactions:

Hives
Swollen lips or tongue
Tickle in throat
Wheezing

Life-threatening reactions:

Blue/gray skin color
Seizures
Unresponsiveness
Inability to breathe

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Insect Stings: What to Do�(1 of 2)

Remove stinger and venom sac using fingernail or plastic card.
Wash with soap and water.
Apply an ice pack.
Give pain medication.
Apply hydrocortisone cream and give antihistamine.

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Insect Stings: What to Do�(2 of 2)

Help administer epinephrine for a severe allergic reaction.
Monitor breathing. If it stops, give CPR.
Have the person suck on ice for a sting in the throat or mouth.

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Spider and Insect Bites

Most spiders are venomous.
About 60 species in North America are capable of biting humans.

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Black Widow Spiders�(1 of 2)

Females are one of the largest spiders.

Fangs can penetrate human skin.
Shiny black or brown abdomens with red or yellow spot or white spots or bands

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Black Widow Spiders�(2 of 2)

Produce one of the most potent venoms
Extensive, irregular, shaggy web
Aggressively defends egg mass
If not guarding eggs, she will attempt to escape rather than bite.

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Black Widow Spider Bites: �What to Look For

Sharp pinprick sensation followed by dull, numbing pain
Two small fang marks
Severe abdominal pain
Headache, chills, fever, heavy sweating, nausea, and vomiting

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Black Widow Spider Bites: �What to Do

Clean with soap and water.
Apply an ice pack.
Give pain medication.
Evacuate immediately.
If facial swelling or anaphylaxis occurs, evacuate and treat appropriately.

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Brown Recluse Spiders

Also known as fiddle-back and violin spiders
Violin shape on back
Fawn to dark brown
Venomous

Courtesy of Kenneth Cramer, Monmouth College.

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Brown Recluse Spider Bites: What to Look For

Mild to severe pain that occurs within 2 to 8 hours
Blister that develops within 48 to 72 hours

Becomes red and bursts
Takes on a bull’s-eye appearance

Fever, weakness, vomiting, joint pain, rash

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Brown Recluse Spider Bites: What to Do

Treat the bite the same as you would a black widow spider bite.
If the wound becomes infected, apply antibiotic ointment under a sterile dressing.
Evacuate.

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Common Aggressive House Spider (Hobo Spider) Bites

What to look for:

Same as for brown recluse spider

What to do:

Treat the bite the same as you would a brown recluse spider bite.

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Tarantulas

Bite only when provoked or roughly handled
When upset, scratches abdomen and flicks hairs onto a person

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Tarantula Bites: �What to Look For

Varies from mild to severe throbbing pain that lasts up to 1 hour.

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Tarantula Bites: What to Do

Treat the same as black widow spider bite.
For hairs in the skin:

Remove with sticky tape.
Wash with soap and water.
Apply hydrocortisone cream.

Give an antihistamine and pain medication.

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Scorpions

Look like miniature lobsters
Death due to scorpion stings in the United States is rare

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Scorpion Stings: �What to Look For

Local immediate pain and burning lasting 6 to 24 hours
Later, numbness or tingling
Severely affected people will experience:

pain along stung arm or leg;
uncontrolled jerking movements; and
fast heart rate, salivation, and breathing distress.

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Scorpion Stings: What to Do

Monitor breathing. If absent, give CPR.
Gently clean with soap and water.
Apply an ice pack.
Give pain medication.
Apply dressing.
Evacuate for severe reactions and any child bitten by a scorpion.

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Chiggers

Troublesome in Southern and Midwestern regions
Bites inflicted by larvae

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Chigger Stings

What to look for:

Itching
Small, red dot that later becomes a red welt
Blisters

What to do:

Treat as an insect sting.
Apply calamine lotion if needed.

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Centipedes

Giant desert centipede is the only US centipede dangerous to humans.
Not to be confused with millipedes, which cannot inject venom but can irritate the skin.

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Centipede Bites: �What to Look For

Burning pain
Local inflammation
Mild swelling of lymph nodes
The bite of the giant desert centipede causes inflammation, swelling, and redness that lasts 4 to 12 hours.

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Centipede Bites: What to Do

Clean with soap and water.
Apply an ice pack.
Give pain medication.
If symptoms persist, give an antihistamine or apply hydrocortisone cream.
For severe reactions, seek medical care.

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Mosquitos

In tropical climates, mosquitoes transmit malaria, yellow fever, and dengue fever.
In the United States, they carry West Nile, Zika, and equine encephalitis viruses.
Breed in water and can be found in marshes, wetlands, and wooded areas.
Most bite at twilight.

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Mosquito Bites: �What to Look For

Itching
Mild swelling

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Mosquito Bites: What to Do

Wash with soap and water.
Apply an ice pack.
Apply calamine lotion or hydrocortisone cream.
For a person with numerous stings or a delayed allergic reaction, give an antihistamine (Benadryl) or apply a hydrocortisone cream on the bite site.

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Ticks�(1 of 3)

Close relatives of mites and spiders
Classified as hard ticks or soft ticks
Need a blood meal to grow
Most bites are painless and harmless.
Carry diseases such as Lyme

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Ticks�(2 of 3)

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Ticks�(3 of 3)

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Embedded Ticks: �What to Look For

No initial pain
Red area around tick
Rash, fever, and chills
Varies from small bump to extensive swelling and ulcer

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Embedded Ticks: What to Do�(1 of 3)

Use tweezers or specialized tool.
Grasp tick as close to skin as possible.
Pull upward and away from skin.

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Embedded Ticks: What to Do�(2 of 3)

For a completely removed tick:

Wash with soap and water. Use rubbing alcohol to further disinfect the area.
Apply an ice pack.
Apply calamine lotion or hydrocortisone cream.
Place tick in bag and bring to a physician.
If a rash, fever, or flulike symptoms occur, seek medical care.

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Embedded Ticks: What to Do�(3 of 3)

If a tick’s mouth parts broke off and remain in the skin:

Leave the parts in place and treat with warm soaks and antibiotic ointment.
The retained parts will usually expel and the skin will heal.
If infection develops, evacuate.

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Lice

Do not live outdoors in the wild
Passed from person to person through clothes, bedding, hats, sexual contact, or poor hygiene.

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Lice: What to Look for

Small (1 to 2 mm) black lice attached to hair shafts
Small, white, wormlike larvae
Red rash or streaks
Severe itching of affected area

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Lice: What to Do

Treat with nonprescription lice shampoo or lotion with permethrin or lindane.
Wash clothes, sleeping bags, pillowcases, or other bedding in soap and hot water.
Do not share clothes or hairbrushes.
Seal contaminated items in a plastic bag for 2 weeks to kill any lice present.