It is usually the female mosquito that bites. It bites into a tiny blood vessel, injecting its saliva into its prey’s bloodstream and then sucking its blood. The contact between the mosquito and the prey’s skin must be six seconds long to bring a reaction. Chemicals, enzymes and proteins present in the mosquito’s saliva prevent the prey’s blood from clotting. These cause the allergic reaction in us and results in localized redness, swelling and itching.
Why do mosquito-bites ‘swell’ up and itch?
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