The only thing peskier than a mosquito bite is the bump on the skin and the urge to scratch that follows.

When a mosquito bites the skin, it deposits antigens, or substances that cause the immune system to produce antibodies. Different insects deposit different antigens — bees deposit pain-producing substances to ward off predators, while mosquitoes transmit antigens that make it easier for them to eat.

But that meal kicks your immune system into gear. Skin cells start to release histamine and other chemicals that cause the blood vessels to dilate and fluid to accumulate near the site of the bite. The result: that fluid-filled, itchy bump that we all know so well.


We dig into the science of mosquito bites — and how to avoid them — in the latest episode of our video series, “Boddities.”

Watch other “Boddities” episodes:


  • Love Boddities. And I swear all the mosquitoes head straight for me, although not all leave weals.

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