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.
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