Whether you’re in the water, on a mountain trail, or in your backyard, the wildlife you encounter have ways of protecting themselves and their territory.

Insects such as bees, ants, fleas, flies, mosquitoes, wasps, and arachnids may bite or sting.

The initial contact of a bite may be painful. It’s often followed by an allergic reaction to venom deposited into your skin through the insect’s mouth or stinger. Most bites and stings trigger nothing more than minor discomfort, but some encounters can be deadly, especially if you have severe allergies to the insect venom.

Prevention is the best medicine, so knowing how to recognize and avoid biting and stinging animals or insects is the best way to stay safe. The animals you should recognize and understand depend very much on where you live or where you’re visiting. Different regions of the United States are home to many of these creatures.

The season also matters. For example, mosquitoes, stinging bees, and wasps tend to come out in full force during the summer.

The form an insect bite takes depends on what type of bug bit you. Take a look at the photos below to help identify which insect may have caused your bug bite.

Warning: Graphic images ahead.

Mosquito bites

Mosquito bites
  • A mosquito bite is a small, round, puffy bump that appears soon after you’ve been bitten
  • The bump will become red, hard, swollen, and itchy
  • You may have multiple bites in the same area
Read full article on mosquito bites.

Fire ant bites

Fire ant bites

This condition is considered a medical emergency. Urgent care may be required.

  • Fire ants are small, aggressive, red or black venomous ants with a painful, stinging bite
  • Bites appear as swollen red spots that develop a blister on top
  • Stings burn, itch, and last up to a week
  • They may cause a dangerous, severe allergic reaction in some people, resulting in swelling, generalized itching, and difficulty breathing
Read full article on fire ant bites.

Flea bites

flea bites
  • Usually located in clusters on the lower legs and feet
  • Itchy, red bump surrounded by a red halo
  • Symptoms begin immediately after being bitten
Read full article on flea bites.

Bedbug bites

Bedbug bites
  • The itchy rash is caused by an allergic reaction to the bite of a bedbug
  • The small rashes have red, swollen areas and dark-red centers
  • Bites may appear in a line or grouped together, usually on areas of the body not covered by clothing, such as the hands, neck, or feet
  • There may be very itchy blisters or hives at the bite site
Read full article on bedbug bites.

Fly bites

Fly bites
  • Painful, itchy rashes are caused by an inflammatory reaction at the site of the fly bite
  • Though usually harmless, they may lead to severe allergic reactions or spread insect-borne diseases
  • Take precautions when traveling to endemic countries by wearing long-sleeved shirts and pants and using bug spray
Read full article on fly bites.

Lice

Lice

Image by: KostaMumcuoglu at the English language Wikipedia [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], via Wikimedia Commons

  • Head lice, pubic lice (“crabs”), and body lice are different species of parasitic lice that affect humans
  • They feed on blood and cause an itchy immune reaction at the site of their bites
  • Adult lice are gray/tan six-legged insects about the size of a tiny sesame seed
  • Nits (eggs) and nymphs (baby lice) can only be seen as very tiny specks that may look like dandruff
Read full article on lice.

Chiggers

Chiggers

Image by: Kambrose123 (Own work) [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons

  • Painful, itchy rashes may be caused by an immune response to the bites of tiny mite larva
  • Bites appear as welts, blisters, pimples, or hives
  • Bites will generally appear in groups and be extremely itchy
  • Chiggers bites may be grouped in skin folds or near areas where clothing fits tightly
Read full article on chigger bites.

Tick bite

tick

Image by: James Gathany Content Providers(s): CDC/ James Gathany [Public domain], via Wikimedia Commons

  • Pain or swelling at the bite area
  • Rash, burning sensation, blisters, or difficulty breathing
  • The tick often remains attached to the skin for a long time
  • Bites rarely appear in groups
Read full article on tick bites.

Scabies

scabies

No machine-readable author provided. Cixia assumed (based on copyright claims). [Public domain], via Wikimedia Commons

  • Symptoms may take four to six weeks to appear
  • Extremely itchy rash may be pimply, made up of tiny blisters, or scaly
  • Raised, white or flesh-toned lines
Read full article on scabies.

Spider bites

Spider bites

Image by: White_tailed_spider.jpg: Ezytyper WhiteTailedSpiderBite.jpg:Ezytyper at en.wikipedia derivative work: B kimmel (White_tailed_spider.jpg WhiteTailedSpiderBite.jpg) [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], from Wikimedia Commons

This condition is considered a medical emergency. Urgent care may be required.

  • Most spiders don't pose a threat to humans, and their bites are harmless or mildly irritating, like a bee sting
  • Dangerous spiders include brown recluse, black widow, hobo spider, funnel web spider (Australia), wandering spider (South America), tarantula, wolf spider
  • A single raised papule, pustule, or wheal may appear at the site of the bite followed by redness and tenderness
  • The bite will appear as two small puncture marks
  • Severe allergic reactions to a spider bite may require medical attention
Read full article on spider bites.

Brown recluse spider

Brown recluse spider

Image by: Tannbreww4828 (Own work) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

  • This is a shy, brown-/tan-colored spider with a violin-shaped patch and six paired eyes: two in the front and two sets of two on either side of the head
  • It likes to hide in quiet, dark places like closets and bookshelves and is native to the South and South Central regions of the United States
  • Nonaggressive, it will only bite humans if it's being crushed between skin and a hard surface
  • Redness appears with a central, white blister at the site of the bite
  • Moderate to severe pain and itching at the site of the bite occurs 2 to 8 hours after the spider has injected its venom
  • Rare complications include fever, body aches, nausea, vomiting, hemolytic anemia, rhabdomyolysis, kidney failure
Read full article on brown recluse spider bites.

Black widow spider

This condition is considered a medical emergency. Urgent care may be required.

  • This spider is plump, black, and shiny, with an hourglass-shaped red mark on its abdomen
  • Nonaggressive, it will only bite if it's being crushed
  • Bites cause muscle pain and spasms in the arms, legs, abdomen, and back
  • Tremor, sweating, weakness, chills, nausea, vomiting, headache are other symptoms
  • The bite area is red with a white center
Read full article on black widow spider bites.

Hobo spider

Hobo spider
  • The venom of this common household spider isn't considered toxic to humans
  • Bites are generally harmless and cause only minor pain and swelling
  • A single, red area appears with a tender central nodule Itching, burning or stinging at the site of the bite
  • Itching, burning or stinging at the site of the bite
Read full article on hobo spider bites.

Wolf spider

bites and stings
  • This large (up to 2 inches long) fuzzy, gray/brown spider is native to many parts of the United States
  • Nonaggressive, it will bite if it feels threatened
  • A tender, itchy red bump appears that heals in 7 to 10 days
Read full article on wolf spider bites.

Horseflies

Horseflies
  • These large (1 inch long) blood-sucking flies are most active in the daylight hours
  • Instant sharp, burning sensation occurs when a horsefly bites
  • Itchiness, redness, swelling and bruising may also occur at the bite location
Read full article on horsefly bites.

Bees

Bees
  • Pain, redness, swelling or itching occurs at the site of the sting
  • A white spot appears where the stinger punctured the skin
  • A bee can only sting one time
Read full article on bee stings.

Yellowjackets

Yellowjackets
  • These thin wasps have black-and-yellow stripes and long dark wings
  • Aggressive, a yellowjacket may sting multiple times
  • Swelling, tenderness, itchiness, or redness may occur near the area that’s been stung
Read full article on yellowjacket stings.

Wasps

Wasps
  • Sharp pain, redness, swelling, and itching or burning occurs at the sting site
  • A raised welt appears around the sting site
  • Wasps can be aggressive and are capable of stinging multiple times
Read full article on wasp stings.

Scorpions

Scorpions
  • These are eight-legged arachnids with large pincers and long, segmented, stinger-tipped tails carried in a forward curve over their backs
  • Many species with variable levels of toxicity can be found all over the world
  • Intense pain, tingling, numbness, and swelling occurs around the sting
  • Rare symptoms include breathing difficulties, muscle twitching, drooling, sweating, nausea, vomiting, increased heartrate, restlessness, excitability, and inconsolable crying
  • Severe symptoms are more likely in infants and children than adults
Read full article on scorpion stings.

Here are some bugs that can be dangerous.

Biting insects, arachnids, and other bugs

Many bugs bite, but only a few do so intentionally. Most bites are relatively harmless, leaving just an itchy patch of skin behind. But some bites can carry disease: Deer ticks, for example, typically carry Lyme disease.

Intentional biters include:

Many larger insects and other bugs won’t seek you out but will bite if handled.

Spiders

Some spiders have poisonous fangs. Poisonous spiders found in the United States include:

Stinging insects

Insects will sting humans only to defend against a perceived threat. Typically, a bee or stinging ant’s stinger will be accompanied by a small amount of venom. When injected into your skin, the venom causes most of the itching and pain associated with the sting. It can also cause an allergic reaction.

Common stinging insects in the United States include:

Scorpions

Scorpions have a reputation for stinging. Many species have barbed tails equipped with poison — 25 species worldwide have poison capable of killing a human being. The most venomous species of scorpion native to the United States is the Arizona bark scorpion.

The venom injected into your body from the bite or sting of an insect will cause your immune system to respond. Often, your body’s immediate response will include redness and swelling at the site of the bite or sting. Minor delayed reactions include itching and soreness.

If you’re very sensitive to an insect’s venom, bites and stings can cause a potentially fatal condition called anaphylactic shock. This can cause the throat to tighten and make breathing difficult.

Some bites and stings may cause illnesses when venom contains infectious agents.

Anyone can be bitten or stung by an insect, and bites and stings are very common. You’re at greater risk if you spend a lot of time outdoors, especially in rural or wooded locations. Children and older adults may have more severe reactions to bites and stings.

If you’re bitten or stung, you may see or feel the insect on your skin during the attack. Some people don’t notice the insect and may not be aware of a bite or sting until one or more of the following symptoms emerge:

  • swelling
  • redness or rash
  • pain in the affected area or in the muscles
  • itching
  • heat on and around the site of the bite or sting
  • numbness or tingling in the affected area

Symptoms of a severe reaction requiring immediate medical treatment include:

  • fever
  • difficulty breathing
  • nausea or vomiting
  • muscle spasms
  • rapid heartbeat
  • swelling of the lips and throat
  • confusion
  • loss of consciousness

If you feel ill or experience flu-like symptoms in the days following an insect bite, see your doctor for tests to rule out infections or diseases you may have contracted from the insect.

Many people are aware they’ve been bitten or stung because they see the insect shortly after the attack. Although you shouldn’t further provoke an attacking insect, try to preserve the insect if it dies following the bite or sting. Its identity may help your doctor to properly diagnose your symptoms. This is especially important for a spider bite, as some species have dangerously potent venom.

The majority of bites and stings can be treated at home, especially if your reaction is mild. Remove the stinger if it’s lodged in your skin, wash the affected area, and apply an ice pack to reduce pain and swelling. Topical anti-itch creams, oral pain relievers, and antihistamines may be used to combat uncomfortable symptoms. You may also want to consider applying a thin paste of baking soda and water to the sting to calm the itching.

Contact emergency services immediately if symptoms of a severe reaction are present. First aid instructions while waiting for paramedics to arrive include loosening the victim’s clothing, laying them on their side, and performing CPR if breathing stops.

If you believe a spider of the black widow or brown recluse variety has bitten you, seek emergency medical treatment even if symptoms seem minor or haven’t emerged. Scorpion bites also should be treated in the emergency room, regardless of symptoms.

Most bites and stings heal by themselves after several days of mild discomfort. Monitor the affected site for signs of infection. Contact your doctor if the wound appears to be getting worse or hasn’t healed after several weeks.

Bites and stings that cause severe reactions can be fatal if they aren’t treated immediately. Once you’ve experienced a severe reaction, your doctor will likely prescribe an auto-injector of epinephrine, a hormone that can prevent anaphylactic shock. Carry it with you at all times to relieve the reaction immediately following a bite or sting.

Use caution when near nests or hives containing aggressive insects. Hire professionals who have the proper safety equipment to remove a nest or hive.

When spending time outside, you can take preventive measures, such as:

  • wearing hats and clothing that provide full coverage
  • wearing neutral colors and avoiding floral patterns
  • avoiding perfume and scented lotion
  • keeping food and drinks covered
  • using citronella candles or insect repellent

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