WHY does a mosquito bite itch?

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WHY does a mosquito bite itch?
 
It's all about the proteins contained in the saliva of a mosquito, the first bite does not bother the immune system, but the subsequent causes a violent response in the form of red permanent itchy spots.
 
After a certain number of bites, the immune system stops overreacting to foreign proteins and the bite sites cease to bother.
 
As it turns out, humans are not really adored by mosquitoes. Buffalo or rat blood, owing to the amino acid isoleucine, is more beloved by mosquitoes.

@Health

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