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Jessi: Hi guys! I just got back from a really fun hike in the woods. I saw a lot of cool things like fall flowers, and lots of birds, and pretty rocks, but I only brought one thing back with me: lots of mosquito bites. Depending on where you live and what time of year it is, if you spend time outside, you've probably been bitten by mosquitoes too. Long after the mosquito is gone, you're left with red, itchy bumps and I mean itchy. So what's going on, why are mosquito bites so itchy?

To answer that question, we need to take a closer look at where these bumps come from. First, let's learn a little bit about the mosquito. For one thing, only female mosquitoes bite, and for another thing, what we call a bite isn't really a bite at all. It's really a jab from a thing called a proboscis. Proboscis! Proboscis is such a fun word to say.

A Proboscis is a special mouth part that some insects have. It looks kind of like a long tube or a straw. If you've ever had the chance to get a close look at a butterfly, maybe you've seen their long curly proboscis which they use as a long tube to sip nectar from flowers. But the female mosquito?

She uses her proboscis to take a tiny sip of blood from the blood vessels right beneath your skin. Her body makes special chemicals to help her do the job. Some of them make your blood easier for her to drink, others even help you from feeling the little pinch when her proboscis pokes you. After she's had her sip and she buzzes off, she leaves a little bit of those chemicals behind in your skin, and they set off signals in your body's immune system.

Your immune system's job is to protect you body from invaders. Not ones from outer space, but invaders like bacteria and viruses, any particles that can make you sick. Kind of like soldiers protecting a fort, your immune system attacks just about anything that it doesn't recognize, and that includes the chemicals left behind by the mosquito.

Once your body discovers it's been bitten by a mosquito, it sends some extra blood and other fluids to the bite. This does a nice job of protecting the area so it can heal, and helps your body get rid of the chemicals that the mosquito left behind, but it also makes the area around the bite swell up, causing a bump. And that swelling sets off nerves in your skin around the bump.

Nerves carry messages between parts of your body, so when you feel the tingly itch of a mosquito bite, that's the work of your nerves telling your brain "In case you haven't noticed, there's something going on down here!" And even though it's really hard, you shouldn't scratch those bumps. It's not good for your skin and it actually makes everything worse.

Scratching irritates your skin even more and when that happens, your body's immune system tries even harder to stop whatever's bothering it, so that makes the bump even itchier. Experts say that using ice or a paste made from baking soda and water on a mosquito bite can actually help with the swelling and the itch. So remember stop scratching! Whatever it takes.

Thanks for joining us on SciShow Kids. Do you have a question about bugs, birds, dinosaurs or anything else? Ask an adult to help you leave a comment below or email us at kids@thescishow.com, and we'll see you next time.

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