About Mosquito bites

There’s no doubt about it. Mosquitoes — and mosquito bites — are annoying. What’s worse, mosquito bites sometimes transmit serious diseases, such as West Nile virus, malaria and dengue fever.

Although your risk of getting diseases from mosquito bites is low, your risk of being bothered by mosquito bites is high. In fact, mosquitoes may be so annoying that they interfere with your enjoyment of time spent outdoors. Although mosquitoes are most prevalent at dawn and dusk, it’s not always possible or desirable to stay indoors during those periods because they’re often peak times for fun activities.

But you can take steps to keep pesky mosquitoes at bay, no matter what time of day it is. And if you get mosquito bites, there are treatments to ease your itch.


Common signs and symptoms
Typical signs and symptoms of mosquito bites include:

  • Soft, initially pale bumps on your skin that can become red
  • Itching

The bump that results from a bite can appear immediately or may take up to two days to appear. Bumps generally range in size from 0.12 inches (0.3 centimeters) to 0.39 inches (1 centimeter) in diameter and are present between two and 10 days. If you’re highly sensitive to mosquito bites, you may have a much larger area of itching.

Severe allergic reaction
Rarely, you may have a serious reaction to mosquito bites, which results in swelling in the throat, significant hives and wheezing. This life-threatening condition (anaphylaxis) requires immediate medical attention.

Mosquito-borne disease
Mosquitoes can transmit serious diseases such as West Nile virus, malaria, yellow fever and dengue fever. Signs and symptoms of a more serious infection may include:

  • Fever
  • Severe headache
  • Body aches
  • Nausea
  • Vomiting
  • Swollen glands
  • Rash
  • Lethargy
  • Confusion
  • Sensitivity to light
  • Jaundice

These signs and symptoms may indicate West Nile fever or another serious infection. Prompt diagnosis and treatment are important.


Mosquito bites are caused by the bite of a female mosquito. The female mosquito feeds off your blood by piercing your skin with her mouth (proboscis). While sucking your blood, she also deposits some of her saliva into your skin. This saliva contains proteins that remain in your skin. Your body’s immune system may then react to those proteins, resulting in the characteristic itching and bump.

Mosquitoes select their victims by evaluating scent, exhaled carbon dioxide and the chemicals in an individual’s sweat. A few factors may put you at greater risk of getting bitten. Mosquitoes are more likely to bite:

  • Men
  • Those with type O blood
  • Overweight individuals

In addition, mosquitoes are attracted to heat. So, wearing dark colors, which absorb heat, may attract mosquitoes.

Age can affect symptom severity
Adults may become less sensitized to mosquito bites if bitten many times throughout life. This means adults are less likely to have strong reactions to mosquito bites. Children who haven’t been bitten as much are at greater risk of experiencing symptoms from a mosquito bite.


  • Infected bites. If you scratch mosquito bites, any resulting sores could become infected.
  • Mosquito-borne diseases. Mosquitoes can act as reservoirs of diseases such as West Nile virus, malaria, yellow fever and dengue fever. The mosquito obtains a virus by biting an infected person or animal. Then, when biting you, the mosquito can transfer that virus to you through its saliva. West Nile is found in the United States. Other diseases such as malaria and dengue fever are far more common in tropical areas of the world. However, a few cases of dengue fever have been reported in the United States.
  • Severe allergic reaction (anaphylaxis). Although rare, you may have a serious reaction to mosquito bites, which can result in swelling in your throat, significant hives and wheezing. This requires immediate medical attention.


To prevent mosquito bites, take steps to reduce the mosquito population around your home. Using insect repellents and protective clothing also can help.

Reducing mosquitoes around your home
Mosquitoes need stagnant or standing water to breed. Eliminate standing water, especially after rains, and you can reduce the mosquito population around your home and yard.

To eliminate standing water:

  • Unclog roof gutters.
  • If possible, empty children’s wading pools at least once a week, and preferably more often.
  • Change water in birdbaths at least weekly. You can also purchase devices to place in birdbaths that keep the water circulating so that mosquitoes won’t lay eggs there.
  • Get rid of old tires in your yard, as they collect standing water.
  • If you keep unused containers, such as flower pots, in your yard, empty them regularly or store them upside down so that they can’t collect water.
  • If you have a fire pit, drain any collected water regularly.

Other methods of controlling mosquitoes are popular, but their effectiveness is unproved. These methods include:

  • Electronic insect control systems, better known as bug zappers
  • Citronella-scented candles
  • Replacing outdoor lights with yellow bug lights
  • Attracting birds and mammals that feed on mosquitoes, such as purple martins and bats

Insect repellents
When used properly, repellents are safe for kids and adults alike. Keep in mind that even though some of them are classified as pesticides by the Environmental Protection Agency (EPA), repellents don’t kill mosquitoes. So you may still see these annoying insects buzzing about. Repellents simply make it more difficult for mosquitoes to find you.

Common insect repellents include:

  • DEET. This pesticide has long been the insect repellent of choice in the United States. DEET blocks a mosquito’s ability to find people who’ve applied it.Apply repellent with a 10 percent to 30 percent concentration of DEET to your skin and clothing. Choose the concentration based on the hours of protection you need — the higher the concentration of DEET, the longer you are protected. A 10 percent concentration protects you for about two hours. Keep in mind that chemical repellents can be toxic, and use only the amount needed for the time you’ll be outdoors. Don’t use DEET on the hands of young children or on infants younger than age 2 months.
  • Picaridin. This repellant, also called KBR 3023, offers protection that’s comparable to DEET at similar concentrations. It also blocks a mosquito’s ability to find people who’ve applied it. Picaridin is nearly odorless, which may make it a good alternative if you’re sensitive to the smells of insect repellents.
  • Oil of lemon eucalyptus. This plant-based chemical may offer protection that’s comparable to low concentrations of DEET. Don’t use this product on children younger than 3 years.
  • Others. Shorter acting repellents — generally containing plant-based oils such as oil of geranium, cedar, lemon grass, soy or citronella — may offer limited protection.

Check the labels of insect repellent products to see which chemicals or other ingredients they contain. And be sure to follow the product’s application guidelines.

Protective clothing
What you wear can also help keep mosquitoes at bay. Clothing tips to keep in mind, particularly in areas that are heavily infested with mosquitoes, include:

  • Wear long-sleeved shirts.
  • Wear socks.
  • Wear long pants and consider tucking your pants into your socks.
  • Wear light-colored clothing, since mosquitoes are more attracted to darker colors.
  • Apply permethrin-containing mosquito repellent to your clothing, shoes, and camping gear and bed netting. You can also buy clothing made with permethrin already in it.
  • Wear a full-brimmed hat to protect your head and neck or a baseball cap with a fold-out flap to protect the back of your neck.
  • Consider wearing a mosquito net to cover your head and face or torso.


Topical treatments
If you scratch mosquito bites, you could break the skin, which may lead to an infection. Instead of scratching, try applying a hydrocortisone cream (0.5 percent or 1 percent), calamine lotion or a baking soda paste to the bite several times a day until your symptoms subside. A baking soda paste can be made with a ratio of 3 teaspoons (15 milliliters) baking soda to 1 teaspoon (5 milliliters) water. A cold pack or baggie filled with crushed ice may help, too.

Oral antihistamines
For stronger reactions, taking an antihistamine containing diphenhydramine (Benadryl, Tylenol Severe Allergy), chlorpheniramine maleate (Chlor-Trimeton, Actifed) or loratadine (Claritin) may ease your body’s response.