Why Do Mosquito Bites Itch?

Have you ever had a perfect summer day ruined by mosquitoes? You’re not alone. These pesky insects sure know how to ruin a fun time.

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But why do mosquitoes bite, and why do the bites itch?


Only female mosquitoes bite. They do because they need to eat blood before they can lay eggs.


Mosquito bites are itchy because your body is having an allergic reaction. When the mosquito bites, it breaks the skin. Some of the insect’s saliva mixes with your blood, and your body views it as a foreign substance it must attack.


This attack is what causes the red, itchy bumps we know as mosquito bites. Sometimes the itchiness develops quickly, but it can take several hours or days.


So how do the mosquitoes find us? They can detect carbon dioxide, the gas in our breath when we exhale. They can also detect our body heat and sweat. Some people get bit by mosquitoes much more than other people, but scientists do not fully know why.


Mosquitoes mostly seem annoying, but they can be dangerous too. Did you know the mosquito is the most dangerous animal in the world? That’s because some mosquitoes carry diseases that can make people sick.


Here in Illinois, the main disease risks from mosquitoes are West Nile virus and encephalitis. You can help stay safe from mosquito bites by asking your parents to help you apply insect repellent before going outside. You can also wear long sleeves and long pants to help keep the bugs away.