Why Do Mosquito Bites Itch?

When a mosquito bites you, it pierces the skin using a special mouthpart called a proboscis to suck up blood. During the feeding process the mosquito injects saliva that contains proteins designed to keep the blood from clotting. These proteins trigger the body’s immune system to produce histamine, which helps white blood cells get to the bitten area. Histamine is the substance that causes the itchiness, redness and swelling.

What Do Mosquito Bites Look Like?

Reactions to mosquito bites usually appear as a reddish, itchy bump that swells up after the bite, and if not treated might become a hard itchy bump within a day or two after the bite.

What Happens When a Mosquito Bites You?

Biting mosquitoes need the protein found in blood to nourish their developing eggs, so only female mosquitoes bite. When a mosquito bites you, it pierces the skin using a special mouthpart to suck up blood. As the mosquito is feeding, it injects saliva into your skin. Your body reacts to the saliva resulting in a bump and itching. Some people have only a mild reaction to a bite or bites. Other people react more strongly, and a large area of swelling, soreness, and redness can occur.

How to Prevent Mosquitoes From Biting?

Preventing mosquito bites involves:

  • Eliminate outdoor sources of water.

  • Wear long-sleeved shirts, long pants and socks to reduce skin exposure to biting mosquitoes.

  • If possible, stay indoors during the times of day or night when mosquitoes are active.

  • Use mosquito repellents that are approved and registered by the Environmental Protection Agency (EPA). Be sure to precisely follow the application directions and warnings when using repellents. When used as directed EPA-registered insect repellents are proven safe and effective. Before deciding upon using repellents, you might consider contacting an Orkin mosquito specialist or your family doctor for their advice.

  • When using repellents on children, apply the repellent to your own hands and then put the repellent on the child. After returning indoors, wash your child's treated skin and clothes with soap and water.

  • If you are also using sunscreen, apply sunscreen first and insect repellent second.

How to Prevent or Reduce the Itching From Mosquito Bites

Wash the bite area with soap and water and apply an ice pack for 10 minutes to reduce swelling and itching. Apply a paste-like mixture of baking soda and water, which can help reduce the itch response. Wait 10 minutes and then wash off the paste. If needed, use an over-the-counter anti-itch or antihistamine cream to help relieve itching and follow the product label directions. Putting calamine lotion or nonprescription hydrocortisone cream on the bite can help ease the itch. Take an antihistamine tablet recommended by your doctor if needed for more adverse reactions.

What Are Mosquitoes Attracted to?

Mosquito researchers have shown that mosquitoes rely on the integration of multiple sensory cues including human body odor, visual recognition, movement of their hosts, carbon dioxide emission, plus stimulus to heat, all of which enable mosquitoes to detect, identify, and locate their hosts. Mosquitoes can become a nuisance and potential disease transmitters. To make sure your home and yard is mosquito-free, contact your Orkin mosquito specialist for advice and recommendations.


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