Why do mosquito bites itch so much? © iStock

Why do mosquito bites itch so much?

Your immune response to mosquito bites depends on how often mosquitos take a fancy to you.

Asked by: Duncan Borg Conti, Malta

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When a mosquito bites, she injects saliva containing anticoagulant enzymes into the wound. The first time you are bitten, nothing happens, but your immune system then begins making antibodies that bind to these foreign proteins. For a while, this immune reaction will cause itchy, swollen bumps. Over many years this response will fade away, but if you go a long time without being bitten, it can start again the next time you are exposed.


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