Mosquito bites are the itchy bumps that appear after mosquitos use their mouthparts to puncture your skin and feed on your blood. Most mosquito bites are harmless, but occasionally a mosquito bite causes a large area of swelling, soreness and redness. This type of reaction, most common in children, is sometimes referred to as skeeter syndrome.
Bites from mosquitoes carrying certain viruses or parasites can cause severe illness. Infected mosquitoes in many parts of the world transmit West Nile virus to humans. Other mosquito-borne infections include yellow fever, malaria and some types of brain infection (encephalitis).
Most people never notice their first mosquito bites. After being bitten several times, though, you're likely to start noticing, often almost immediately after the mosquito feeds. The signs include:
In children and people with immune system disorders, mosquito bites sometimes trigger:
When to see a doctor
Mosquito bites are caused by female mosquitoes feeding on your blood. Female mosquitoes have a mouthpart made to pierce skin and siphon off blood. Males lack this blood-sucking ability because they don't produce eggs and so have no need for protein in blood.
As a biting mosquito fills itself with blood, it injects saliva into your skin. Proteins in the saliva trigger a mild immune system reaction that results in the characteristic itching and bump.
Mosquitoes select their victims by evaluating scent, exhaled carbon dioxide and the chemicals in a person's sweat. There's conflicting evidence about whether mosquitoes prefer women or men.
Because most adults have had mosquito bites throughout their lives, an adult is less likely to have a severe reaction than is a child.
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 or parasite to you through its saliva. West Nile and encephalitis viruses are found in the United States. Dengue fever, although it is rare, has been reported in the southeastern United States. Other diseases, such as malaria and yellow fever, are far more common in tropical areas of the world.
Preparing for your appointment
You won't need to see your doctor for a mosquito bite. If you develop a fever or other signs and symptoms of illness possibly associated with a mosquito bite, you'll need to visit your primary care physician.
Here's some information to help you get ready for your appointment.
What you can do
If you're having symptoms you think might be related to a mosquito bite, some basic questions you might have include:
What you can do in the meantime
Tests and diagnosis
Doctors can usually identify mosquito bites by sight, particularly during seasons and in warm, humid regions with many mosquitoes.
The red, itchy, painful swelling referred to as skeeter syndrome is sometimes mistaken for a secondary bacterial infection brought on by excessive scratching and broken skin. Skeeter syndrome is actually the result of an allergic reaction to proteins in mosquito saliva. There's no simple blood test to detect mosquito antibodies in blood, so mosquito allergy is diagnosed by history of mosquito exposure followed by large, red areas of swelling and itching.
Treatments and drugs
Most mosquito bites stop itching and heal on their own without medical treatment.
You can take a number of steps to limit your exposure to mosquitoes and protect yourself from bites when mosquitoes are unavoidable.
Use insect repellent
These repellents temporarily keep hungry mosquitoes from identifying you as a food source. The higher the concentration of DEET or picaridin in a product, the longer its protection will last. An application of a standard oil of lemon eucalyptus product protects you about as long as a product containing DEET at a low concentration.
Used according to package directions, insect repellents are generally safe for children and adults, with a few exceptions:
Treat clothing and outdoor gear
Wear protective clothing
Reduce mosquitoes around your home
Last Updated: 2012-10-24
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