Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, some mosquitoes spread West Nile virus. Travelers outside the United States may be at risk for malaria and other infections.

To prevent insect bites and their complications

• Don't bother insects
• Use insect repellant
• Wear protective clothing
• Be careful when you eat outside because food attracts insects
• If you know you have severe allergic reactions to insect bites and stings (such as anaphylaxis), carry an emergency epinephrine kit

Flying Insects

Outdoor workers are at risk of being stung by flying insects (bees, wasps, and hornets) and fire ants. While most stings cause only mild discomfort, some may result in severe allergic reactions that require immediate medical care and may cause death.

First Aid

If a worker is stung by a stinging insect:

• Have someone stay with the worker to be sure that they do not have an allergic reaction.
• Wash the site with soap and water.
• Remove the stinger using gauze wiped over the area or by scraping a fingernail over the area.
  • Never squeeze the stinger or use tweezers.
• Apply ice to reduce swelling.
• Do not scratch the sting as this may increase swelling, itching, and risk of infection.

Protect Yourself

• Wear light-colored, smooth-finished clothing.
• Avoid perfumed soaps, shampoos, and deodorants.
  • Do not wear cologne or perfume.
• Wear clean clothing and bathe daily.
• Wear clothing to cover as much of the body as possible.
• Avoid flowering plants when possible.
• Keep work areas clean. Some insects are attracted to discarded food.
• Remain calm and still if a single stinging insect is flying around. (Swatting may cause it to sting.)
• If attacked by several stinging insects, run to get away. (Bees release a chemical when they sting, which attracts other bees.)
  • Go indoors.
  • Shaded areas are better than open areas.
  • Do not jump into water. Some insects (ex. Africanized honey bees) are known to hover above the water.
• If an insect is inside your vehicle, stop slowly, and open all the windows.
• Workers with a history of severe allergic reactions to insect bites or stings should carry an epinephrine autoinjector and wear medical ID jewelry stating their allergy.

Fire Ants

Fire ants bite and sting. They are aggressive when stinging and inject venom, which causes a burning sensation. Red bumps form at the sting, and within a day or two they become white fluid-filled pustules.

First Aid

• Rub off ants briskly, as they will attach to the skin with their jaws.
• Antihistamines may help.
  • Follow directions on packaging.
  • Drowsiness may occur.
• Seek immediate medical attention if a sting causes severe chest pain, nausea, severe sweating, loss of breath, serious swelling, or slurred speech.

Protect Yourself

• Do not disturb ant mounds.
• Be careful when lifting items (including animal carcasses) off the ground, as they may be covered in ants.
• Fire ants may be found on trees and in water, so always look over the area before starting to work.
• Tuck pants into socks or boots.
• Workers with a history of severe allergic reactions to insect bites or stings should carry an epinephrine autoinjector and wear medical ID jewelry stating their allergy. Fire ants bite and sting. They are aggressive when stinging and inject venom, which causes a burning sensation. Red bumps form at the sting, and within a day or two they become white fluid-filled pustules.

Summer can be a bummer if outdoor fun is interrupted by the irritating buzz of mosquitoes. Their bites not only create itchy red bumps on your skin; they also carry the risk of disease. NIH-funded scientists are working to find better ways to diagnose, treat, and prevent mosquito-borne illnesses. And we can all take simple steps to avoid getting bit by those blood-sucking insects.

Most mosquito bites are relatively harmless. The itchy bumps often last for just a day or 2 after a mosquito has punctured your skin. But if the mosquito is carrying certain germs, like viruses or parasites, these pathogens might enter your blood during the bite and make you sick.

The diseases spread by mosquito bites can be serious. Some experts call mosquitoes the world’s most deadly animal. Mosquito-related illnesses kill about 725,000 people worldwide each year. By comparison, snakes kill about 50,000; tapeworms about 2,000; and sharks only about 10 people per year across the globe.

Most mosquito-related deaths and illnesses occur outside the U.S., mainly in Africa. “But we’ve always had a variety of mosquito-borne pathogens in the U.S. as well,” says Dr. Thomas W. Scott, an expert on insect-borne diseases at the University of California, Davis. “Right now, I’d say West Nile virus is the biggest problem in the continental United States.”

West Nile tends to be a seasonal epidemic in the U.S. It flares up in late spring or early summer and continues into the fall. In 2015, more than 2,000 cases of West Nile disease arose nationwide, and the virus was blamed for nearly 120 deaths.

Most people with West Nile infections have no symptoms. Roughly 1 in 5 infected people have relatively mild symptoms, such as fever, headache, or nausea. West Nile can become serious or even deadly for about 1 in 150 infected people.

Another virus, called dengue, is one of the most common causes of mosquito-borne disease worldwide. A dengue outbreak in Hawaii has affected hundreds of people since late 2015.

No medications are available to treat the many viral diseases transmitted by mosquitoes. But current drugs can treat and prevent malaria, which is caused by a tiny mosquito-borne parasite and not a virus.

A few mosquito-borne illnesses, such as yellow fever and Japanese encephalitis, are preventable by vaccination. But vaccines are not yet available to protect against most mosquito-related diseases, including malaria and West Nile virus.

NIH scientists are working to develop and test potential new vaccines for dengue and West Nile viruses. An experimental dengue vaccine that showed promise in a small clinical trial is now being evaluated in a larger population in Brazil.

Zika is another mosquito-borne virus that’s spreading throughout Central and South America. Because the dengue and West Nile viruses are closely related to the Zika virus, NIH researchers plan to create an experimental Zika vaccine by using methods similar to those used for the other vaccines. Small clinical trials may begin soon, but years of testing will be needed to fully evaluate potential Zika vaccines.

While preventive vaccines are still in development, Scott says, “There are things we can do right now to help protect against mosquito-borne disease.”

Avoid Mosquito Bites

• Use insect repellents. Products containing DEET, picaridin, lemon eucalyptus, para-menthane-diol, or IR3535 can be applied to skin. Follow label instructions.
• Cover up. When outside, wear long sleeves, pants, and socks. Mosquitoes may bite through thin fabric, so spray thin clothes with an EPA-registered repellent like permethrin. Don’t apply permethrin directly to skin.
• Mosquito-proof your home. Install or repair screens on windows and doors to keep insects out. Use air conditioning if you have it.
• Get rid of mosquito breeding sites. Empty standing water from flowerpots, gutters, buckets, pool covers, pet water dishes, and birdbaths on a regular basis.

Stinging or biting insects or scorpions can be hazardous to outdoor workers. Stinging or biting insects include bees, wasps, hornets, and fire ants.

The health effects of stinging or biting insects or scorpions range from mild discomfort or pain to a lethal reaction for those workers allergic to the insect’s venom. Anaphylactic shock is the body’s severe allergic reaction to a bite or sting and requires immediate emergency care. Thousands of people are stung by insects each year, and as many as 90–100 people in the United States die as a result of allergic reactions. This number may be underreported as deaths may be mistakenly diagnosed as heart attacks or sunstrokes or may be attributed to other causes.

It is important for employers to train their workers about their risk of exposure to insects and scorpions, how they can prevent and protect themselves from stings and bites, and what they should do if they are stung or bitten.

Bees, wasps, and hornets are most abundant in the warmer months. Nests and hives may be found in trees, under roof eaves, or on equipment such as ladders.

U.S. Geographic Region

Bees, wasps, and hornets are found throughout the United States.

Employer Recommendations

Employers should protect their workers from stinging insects by training them about:

• Their risk of exposure
• Insect identification
• How to prevent exposure
• What to do if stung

Worker Recommendations

Workers should take the following steps to prevent insect stings:

• Wear light-colored, smooth-finished clothing.
• Avoid perfumed soaps, shampoos, and deodorants.
  • Don’t wear cologne or perfume.
  • Avoid bananas and banana-scented toiletries.
• Wear clean clothing and bathe daily. (Sweat may anger bees.)
• Wear clothing to cover as much of the body as possible.
• Avoid flowering plants when possible.
• Keep work areas clean. Social wasps thrive in places where humans discard food.
• Remain calm and still if a single stinging insect is flying around. (Swatting at an insect may cause it to sting.)
• If you are attacked by several stinging insects at once, run to get away from them. (Bees release a chemical when they sting, which may attract other bees.)
  • Go indoors.
  • A shaded area is better than an open area to get away from the insects.
  • If you are able to physically move out of the area, do not to attempt to jump into water. Some insects (particularly Africanized Honey Bees) are known to hover above the water, continuing to sting once you surface for air.
• If a bee comes inside your vehicle, stop the car slowly, and open all the windows.
• Workers with a history of severe allergic reactions to insect bites or stings should consider carrying an epinephrine auto injector (EpiPen) and should wear a medical identification bracelet or necklace stating their allergy.

First Aid

If a worker is stung by a bee, wasp, or hornet:

• Have someone stay with the worker to be sure that they do not have an allergic reaction.
• Wash the site with soap and water.
• Remove the stinger using gauze wiped over the area or by scraping a fingernail over the area.
  • Never squeeze the stinger or use tweezers.
• Apply ice to reduce swelling.
• Do not scratch the sting as this may increase swelling, itching, and risk of infection.

Imported fire ants first came to the United States around 1930. Now there are five times more ants per acre in the United States than in their native South America. The fire ants that came to the United States escaped their natural enemies and thrived in the southern landscape.

Fire ants bite and sting. They are aggressive when stinging and inject venom, which causes a burning sensation. Red bumps form at the sting, and within a day or two they become white fluid-filled pustules.

U.S. Geographic Region

Mostly the Southeastern United States, with limited geographic distribution in New Mexico, Arizona, and California.

Employer Recommendations

Employers should protect their workers from fire ants by training them about:

• Their risk of exposure
• How to identify fire ants and their nests
• How to prevent exposure
• What to do if they are bitten or stung

Worker Recommendations

Workers should take the following steps to prevent fire ant stings and bites:

• Do not disturb or stand on or near ant mounds.
• Be careful when lifting items (including animal carcasses) off the ground, as they may be covered in ants.
• Fire ants may also be found on trees or in water, so always look over the area before starting to work.

First Aid

Workers with a history of severe allergic reactions to insect bites or stings should consider carrying an epinephrine auto injector (EpiPen) and should wear a medical identification bracelet or necklace stating their allergy.

Workers should take the following steps if they are stung or bitten by fire ants:

• Rub off ants briskly, as they will attach to the skin with their jaws.
• Antihistamines may help.
  • Follow directions on packaging.
  • Drowsiness may occur.
• Take the worker to an emergency medical facility immediately if a sting causes severe chest pain, nausea, severe sweating, loss of breath, serious swelling, or slurred speech.

Scorpions usually hide during the day and are active at night. They may be hiding under rocks, wood, or anything else lying on the ground. Some species may also burrow into the ground. Most scorpions live in dry, desert areas. However, some species can be found in grasslands, forests, and inside caves.

U.S. Geographic Region

Southern and Southwestern United States.

Symptoms

Symptoms of a scorpion sting may include:

• A stinging or burning sensation at the injection site (very little swelling or inflammation)
• Positive “tap test” (i.e., extreme pain when the sting site is tapped with a finger)
• Restlessness
• Convulsions
• Roving eyes
• Staggering gait
• Thick tongue sensation
• Slurred speech
• Drooling
• Muscle twitches
• Abdominal pain and cramps
• Respiratory depression

These symptoms usually subside within 48 hours, although stings from a bark scorpion can be life-threatening.

Employer Recommendations

Employers should protect their workers from scorpions by training them about:

• Their risk of exposure
• Scorpion identification
• How to prevent exposure
• What to do if stung

Worker Recommendations

Workers should take the following steps to prevent scorpion stings:

• Wear long sleeves and pants.
• Wear leather gloves.
• Shake out clothing or shoes before putting them on.
• Workers with a history of severe allergic reactions to insect bites or stings should consider carrying an epinephrine auto injector (EpiPen) and should wear a medical identification bracelet or necklace stating their allergy.

First Aid

Workers should take the following steps if they are stung by a scorpion:

• Contact a qualified health care provider or poison control center for advice and medical instructions.
• Ice may be applied directly to the sting site (never submerge the affected limb in ice water).
• Remain relaxed and calm.
• Do not take any sedatives.
• Capture the scorpion for identification if it is possible to do so safely.

Avoid bug bites

Bugs, including mosquitoes, ticks, fleas, and flies, can spread diseases such as malaria, yellow fever, Zika, dengue, chikungunya, and Lyme. While some cases are mild, these diseases can be severe and have lasting consequences. Some diseases caused by bug bites can be prevented with vaccines or medication, like yellow fever and malaria; however, many cannot, such as Zika and Lyme. On your trip. avoid bug bites to prevent getting sick.

Check Your Destination

Your destination and activities may determine what steps you need to take to protect yourself from bug bites. Check CDC Destinations pages to see what vaccines or medicines you may need and what diseases or health risks are a concern at your destination.

Your Activities Can Increase Your Risk for Bug Bites

Some activities put you more at risk for bug bites than others. Activities that can increase your chances of getting bug bites include hiking, camping, working with animals, and visiting farms and forested areas.

Take Steps to Prevent Bug Bites During Your Trip

Use insect repellent

• Use Environmental Protection Agency (EPA)-registered insect repellents with one of the active ingredients below. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women.
  • DEET
  • Picaridin (known as KBR 3023 and icaridin outside the US)
  • IR3535
  • Oil of lemon eucalyptus (OLE)
  • Para-menthane-diol (PMD)
  • 2-undecanone

Find the right insect repellent for you by using EPA's search tool.

• If you are also using sunscreen, apply sunscreen first, and insect repellent second.
• Do not spray repellent on the skin under clothing.
• Insect repellent tips for babies and children
  • Dress your child in clothing that covers arms and legs.
  • Cover strollers and baby carriers with mosquito netting.
  • When using insect repellent on your child:
    • Always follow label instructions.
    • Do not use products containing oil of lemon eucalyptus (OLE) or para-menthane-diol (PMD) on children under 3 years old.
    • Do not apply insect repellent to a child’s hands, eyes, mouth, cuts, or irritated skin.
      • Adults: Spray insect repellent onto your hands and then apply to a child’s face.

Wear long-sleeved shirts and long pants

Treat clothing and gear with permethrin

• Use 0.5% permethrin to treat clothing and gear (such as boots, pants, socks, and tents) or buy permethrin-treated clothing and gear.
  • Permethrin is an insecticide that kills or repels mosquitoes.
  • Permethrin-treated clothing provides protection after multiple washings..
  • Read product information to find out how long the protection will last.
• If treating items yourself, follow the product instructions.
• Do not use permethrin products directly on skin.

Keep mosquitoes out of your hotel room or lodging

• Choose a hotel or lodging with air conditioning or window and door screens.
• Use a mosquito net if you are unable to stay in a place with air conditioning or window and door screens or if you are sleeping outside.

Sleep under a mosquito net

• Sleep under a mosquito net if you are outside or when screened rooms are not available. Mosquitoes can live indoors and bite during the day and night.
• Buy a mosquito net at your local outdoor store or online before traveling overseas.
• Choose a mosquito net that is compact, white, rectangular, with 156 holes per square inch, and long enough to tuck under the mattress.
• Permethrin-treated mosquito nets provide more protection than untreated nets.
  • Permethrin is an insecticide that kills mosquitoes and other insects.
  • To determine if you can wash a treated mosquito net, follow the label instructions.

If you are bitten by mosquitoes, avoid scratching the bites and apply over-the-counter anti-itch or antihistamine cream to relieve itching.

Additional steps you can take to prevent or quickly find tick bites

Prevent Tick Bites

• Know where to expect ticks. Ticks live in grassy, brushy, or wooded areas, or even on animals. Spending time outside walking your dog, camping, gardening, or hunting could bring you in close contact with ticks. Many people get ticks in their own yard or neighborhood.
• Treat clothing and gear with products containing 0.5% permethrin. Permethrin can be used to treat boots, clothing and camping gear and remain protective through several washings. Alternatively, you can buy permethrin-treated clothing and gear.
• Use Environmental Protection Agency (EPA)-registered insect repellents containing DEET, picaridin, IR3535, Oil of Lemon Eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. EPA’s helpful search tool can help you find the product that best suits your needs. Always follow product instructions. Do not use products containing OLE or PMD on children under 3 years old.
• Avoid Contact with Ticks
  • Avoid wooded and brushy areas with high grass and leaf litter.
  • Walk in the center of trails.

Find and Remove Ticks

• Check your clothing for ticks. Ticks may be carried into the house on clothing. Any ticks that are found should be removed. Tumble dry clothes in a dryer on high heat for 10 minutes to kill ticks on dry clothing after you come indoors. If the clothes are damp, additional time may be needed. If the clothes require washing first, hot water is recommended. Cold and medium temperature water will not kill ticks.
• Examine gear and pets. Ticks can ride into the home on clothing and pets, then attach to a person later, so carefully examine pets, coats, and daypacks.
• Shower soon after being outdoors. Showering within two hours of coming indoors has been shown to reduce your risk of getting tickborne diseases. Showering may help wash off unattached ticks and it is a good opportunity to do a tick check.

Common Bugs and Diseases They Spread

• Mosquitoes
  • Chikungunya
  • Dengue
  • Japanese Encephalitis
  • Malaria
  • Murray Valley Encephalitis virus
  • Rift Valley Fever
  • Ross River virus disease
  • West Nile virus
  • Yellow Fever
  • Zika
• Ticks
  • African Tick-Bite Fever
  • Tick-borne Encephalitis
• Fleas
  • Plague
• Tsetse Fly
  • African Trypanosomiasis (African Sleeping Sickness)
• Triatomine (kissing) bugs
  • Chagas Disease (American Trypanosomiasis)