Alen J

Why mosquito bites swells and itches ?


When a mosquito flies off after biting, it leaves some of its anti-coagulant saliva behind  which was used to suck blood. This triggers immune responses, leading to the production of antibodies and histamine which in turn leads to the generation of more blood vessels so that more and more white blood cells and proteins can reach the affected area to counter the foreign object.



This  overall reaction results a small bump at the bitten area and red color with more blood vessels generated.

And when the affected area swells, small nerve cells beneath the skin membrane gets slightly squeezed resulting itching sensation.

Image Sources -

http://www.crazylifehacks.com
http://www.scs.illinois.edu
http://www.biologymad.com
http://www.rosslab.neurobio.pitt.edu