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
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.
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.
Authors
Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
