Ticks
![Ticks are often found in plants and brush, and can attach to and bite people and animals.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s1.jpg?resize=650px:*&output-quality=75)
Ticks are often found in plants and brush, and can attach to and bite people and animals. Their bites are usually not harmful; however, these insects can carry serious diseases including Lyme disease and Rocky Mountain spotted fever.
Tick Bites
![Most commonly, ticks attach to warm, moist, and hard-to-see parts of the body including the scalp, armpits, groin, skin folds, and other hairy areas.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s2.jpg)
What does a tick bite look like? Most commonly, ticks attach to warm, moist, and hard-to-see parts of the body including the scalp, armpits, groin, skin folds, and other hairy areas. Ticks must be removed properly with tweezers to minimize the chances of infection from these insects.
- Wear appropriate clothing outdoors to reduce exposure
- Use tick repellant with DEET
- Check for ticks on your body if you spend time in the woods
Lyme Disease
![A circular, red, expanding rash (a 'bulls-eye' rash) is one of the first symptoms of Lyme disease.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s3.jpg)
What does a Lyme disease rash look like? A Lyme disease- causing bacterium is carried in the bug bite of the deer tick (in the northeastern, mid-Atlantic, and north-central U.S.) or the western blacklegged tick on the Pacific Coast. In most cases, a tick—an insect about 3 to 5 mm long—must be attached 36-48 hours to spread Lyme disease. A circular, red, expanding rash (erythema migrans, or a “bulls-eye” rash) may be one of the first symptoms of Lyme disease. Other symptoms include fatigue, chills, fever, headache, muscle and joint aches, and swollen lymph nodes. Treatment in the early stages with antibiotics is generally effective.
Poisonous Black Widow Spiders
![Only the female of the species bites humans.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s4.jpg)
Black widows are about ½ inch wide; with a shiny, black, globular abdomen that has the distinctive red hourglass on the underside. Only the female of the species bites humans. They live throughout the U.S., but most are found in the southern regions.
Black Widow Bites
![Black widow spider bite symptoms usually start 20 minutes to one hour following the bite.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s5.jpg)
This is what a black widow bite looks like. Black widow spider bite symptoms usually start 20 minutes to one hour following the bite, and can include pain, though not all people experience pain. Other symptoms include muscle cramps and spasms, abdominal pain, tremors, weakness, or a rise in blood pressure. Seek medical attention immediately. Treatment includes antivenin (which counteracts the spider toxin) and pain medications if necessary.
Brown Recluse Spiders
![Brown recluse spiders are extremely poisonous, and their bug bites can cause infection and illness.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s6.jpg)
Brown recluse spiders are extremely poisonous, and their bug bites can cause infection and illness. They are found mostly in the Midwestern and Southeastern U.S. They are yellowish-tan to dark brown in color with darker legs that are about one inch in length. They have a characteristic violin pattern on their back.
Brown Recluse Bites
![Brown recluse bites are usually painless.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s7.jpg)
Brown recluse bites are usually painless, but some may feel like a mild bee sting. Symptoms of a brown recluse bug bite include severe pain at the site of the bite that develops about four hours after the bite, followed by severe itching, nausea, vomiting, fever, and muscle pain. See a doctor immediately if you think you have been bitten by a brown recluse spider bite. If possible, safely bring the spider to the ER for proper identification.
Head Lice
![Head lice are about 2-3 millimeters (mm) long, and they infest the head and neck area, usually hidden in your hair.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s8.jpg)
Head lice are about 2-3 millimeters (mm) long, and they infest the head and neck area, usually hidden in your hair. These insects spread through direct contact with the hair of a person infested with head lice. It is most common among preschool and elementary school-aged children, and members of the household of children who are infested with head lice. Head lice are not known for spreading disease; however, they may cause itching, and scratching that may lead to infection.
Head Lice Remedies
![Treatment is recommended for anyone with an active infestation of head lice.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s9.jpg)
Want to know how to get rid of head lice? Treatment is recommended for anyone with an active infestation of head lice. Pediculicides (medicines that kill lice) may be prescribed by your doctor. Wash all clothing and bedding used by the person infested with these bugs. Often, it is recommended that family members also be treated at the same time to prevent further head lice infestation.
Fleas: Not for Pets Only
![Fleas are not just a problem for Fido – these blood-sucking bugs bite people, too.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s10.jpg)
Fleas are not just a problem for Fido – these blood-sucking bugs bite people, too. Fleas are about 2.5 millimeters (mm) long, they are reddish-brown in color, and while wingless, they can jump large distances. They suck blood from their host to feed.
Flea Bites
![Some people may develop an allergic reaction to a flea bite.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s11.jpg)
What do flea bites look like? Some people may develop an allergic reaction to a flea bite. Scratching a flea bite itch can cause the skin on and around the bitten area to break open, which can lead to infection. Keep these insects away by making sure all pets in your home are on flea preventative products, keeping your home clean, and by treating any flea infestations that may occur.
Bee, Hornet, Wasp, Yellow Jacket
![The stings of bees, wasps, hornets, and yellow jackets can cause severe reactions in people who are allergic to their stings.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s12_2.jpg)
The stings of bees, wasps, hornets, and yellow jackets can cause severe reactions in people who are allergic to their stings. Normal reactions include pain, redness, and swelling around the site of the sting.
Bee, Hornet, Wasp, Yellow Jacket Stings
![If you are allergic to bees, hornets, wasps, or yellow jackets, seek emergency care immediately to prevent or manage an anaphylactic reaction.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s13.jpg)
This is what a bee sting looks like. If you are allergic to bees, hornets, wasps, or yellow jackets, seek emergency care immediately to prevent or manage an anaphylactic reaction. Use an EpiPen (epinephrine) if you have one. In all cases, remove the insect’s stinger, if possible, to avoid receiving more venom (tweezers may help), and clean the sting area with antiseptic. You may take over-the-counter antihistamines for itching or hives, and over-the-counter nonsteroidal anti-inflammatories (NSAIDs) for pain and inflammation.
Fire Ants
![The red imported fire ant is found mainly in the Southern U.S.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s14_2.jpg)
The red imported fire ant is found mainly in the Southern U.S. They are reddish brown to reddish black and have a stinger. They build large dirt mounds, usually in sunny areas. Bug bites from fire ants are usually painful, and will cause itchy, raised areas on your skin (hives), followed by pimple-like, pus-filled blisters.
Fire Ant Stings
![When a fire ant bites you, you will feel it! An itchy hive will develop.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s15.jpg)
When a fire ant bites you, you will feel it! An itchy hive will develop. Hours later, a blister filled with pus can form. If you suffer from a severe allergic reaction to a fire ant bite, these bug bites can be life-threatening. Seek medical care immediately. Otherwise, to help relieve the pain and itching, use over-the-counter pain relievers and antihistamines. Do not break the blisters, and keep the area clean to avoid secondary infection.
Chiggers
![Chiggers are a type of mite from the family known as Trombiculidae.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s16_2.jpg)
Chiggers leave a painful bite. Chiggers are a type of mite from the family known as Trombiculidae. They are barely visible to the naked eye, and in their juvenile (larval) form, they can bite humans. Chiggers found in the U.S. do not spread disease, but their bites can cause intense itching and small red bumps.
Chigger Bites
![Itching from chigger bites is most intense 1 to 2 days following the bite](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s17.jpg)
This is what chigger bites look like. Itching from chigger bites is most intense 1 to 2 days following the bite. When the chigger falls off it can leave red welts that may resemble a blister or pimple. Scratching can lead to a secondary infection, so treatment is directed at relief of itching symptoms. Use over-the-counter antihistamine creams to help relieve itching and prevent scratching. Consult your doctor if you have concerns.
Scabies
![Scabies are mites that burrow into the skin, causing intense itching.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s18.jpg)
Scabies are mites that burrow into the skin, causing intense itching. Scabies spread by close contact with a person infested with scabies, or by sharing towels, sheets, and other personal items with a person infested with scabies.
Treating Scabies
![The intense itch is usually worse at night.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s19.jpg)
It can take weeks after the scabies mites burrow into the skin before you will experience severe itching or rash, with small blisters or sores. The intense itching is usually worse at night. Most commonly, the itching will be between the fingers, on the outside of the elbows or armpits, around the waistline, or on the buttocks. Scabies can only be cured with medicated creams, lotions, or pills. Family members who share a household with a person infested with scabies may also be prescribed treatment.
Bed Bugs
![Bed bugs are reddish brown, and less than 1 millimeter (mm) in size.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s20.jpg)
Bed bugs are reddish brown, and less than 1 millimeter (mm) in size. They are frequently found in bedding, but can also be found in areas of clutter, or in old furniture.
Bed Bug Bites
![Most of the time, the reaction to a bed bug bite is mild.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s21.jpg)
What do bed bugs look like? Most of the time, the reaction to a bed bug bite is mild, and usually in the form of small, red, itchy bumps. Treatment includes over-the-counter cortisone creams and antihistamines to relieve the itch. Excessive scratching can cause a secondary infection.
Puss Caterpillar
![The puss caterpillar (woolly slug, or asp) is the most toxic caterpillar in the U.S.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s22.jpg)
The puss caterpillar (woolly slug, or asp) is the most toxic caterpillar in the U.S., and is found mostly in Southern states. This unusual bug measures about 1 inch long and appears furry. The longer hairs camouflage spines that have venom. The puss caterpillar feeds on shade trees such as elm, oak, and sycamore, or bushes such as holly.
Puss Caterpillar Stings
![Symptoms of a puss caterpillar bite include immediate waves of intense pain, itchy rash, nausea and vomiting, restlessness, fever, muscle cramps, and symptoms of shock.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s23.jpg)
This is what a puss caterpillar sting looks like. Symptoms of a puss caterpillar bite include immediate waves of intense pain, itchy rash, nausea and vomiting, restlessness, fever, muscle cramps, and symptoms of shock. If you come into contact with a puss caterpillar, remove the broken-off spines by using cellophane tape or a commercial facial peel, and call your doctor. Apply an ice pack and take over-the-counter antihistamines to relieve itchiness.
Scorpion Stings
![Scorpions are related to spiders and mites.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s24.jpg)
Scorpions are related to spiders and mites, and are found mostly in the Southern and Western U.S. They range in length from about 9 to 21 cm, and the last tail segment contains the stinger that transmits a toxin to the recipient of a sting. Most scorpions are harmless, but some can be lethal. Scorpion sting symptoms include pain, swelling, and itching at the sting site. Severe symptoms include numbness, difficulty swallowing, blurred vision, seizures, and difficulty breathing. Seek medical attention immediately if stung by a scorpion and begin to develop intense symptoms.
Painful Deerflies
![Deer flies are about the same size as houseflies.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s25.jpg)
Deer flies are about the same size as houseflies, and they are yellow or black in color, with patterned wings. They are mostly active on warm, sunny days with little wind and they thrive in areas such as beaches, lakes, or woods near damp areas. Bites are usually painful, though most of the time not severe. In rare cases, the flies can transmit the Tularemia bacterium, which requires medical attention. Prevent deerfly bites by wearing protective clothing and using insect repellent.
Annoying Mosquitoes
![For the most part, mosquitoes cause itchy hives when they bite.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s26.jpg)
For the most part, mosquitoes cause itchy hives when they bite. But they can also carry diseases such as Zika, West Nile virus, dengue fever virus, malaria, chikungunya virus and others. Scratching mosquito bites can also cause infection. Prevent mosquitoes in your yard by draining standing water. Keep them out of your home by using window screens. To protect yourself, always use insect repellent when outdoors, wear protective clothing, and avoid being outdoors during peak mosquito hours of dawn and dusk.
Houseflies
![The housefly is a nuisance pest that can spread diseases such as food poisoning and dysentery.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s27_houseflies.jpg)
The housefly is a nuisance pest that can spread diseases such as food poisoning and dysentery. They are gray-colored and about 1/4-inch long. They are attracted to trash, manure, carrion, and moist areas, and can spread bacteria from those areas to parts of your home. Proper sanitation is essential to manage houseflies. Keep trash and food in sealed containers.
Cockroaches
![Cockroaches can be found all over the world and can trigger asthma and allergic reactions.](https://images.emedicinehealth.com/images/slideshow/bad_bugs_s28.jpg)
Cockroaches can be found all over the world. They not only carry diseases such as salmonella, they can cause allergic reactions. Symptoms of allergy to cockroaches can include itchy skin, scratchy throat, itchy eyes and nose, and even asthma. Prevent cockroach infestation and manage allergic reactions by keeping your home clean and in good repair, and keeping trash covered. Use pest control if needed.
Bad Bugs: Identify Insects and Bug Bites
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