Today I found out why mosquito bites itch.
When female mosquitoes poke their proboscis through your skin so they can suck some of your blood to be later used to make eggs, they inject you with some of their saliva. This saliva helps them to drink your blood more quickly, because it contains a cocktail of anticoagulants. Once the female mosquito is full up of your blood or is disturbed, she flies away, leaving some of her saliva behind. Your body then kicks your immune system in gear as a response to the presence of this saliva. It produces various antibodies which in turn bind to the antigens in the mosquito’s saliva. This then triggers the release of histamine.
Histamine is a nitrogen compound that, among other things, triggers an inflammatory response. It also helps white blood cells and other proteins to engage invaders in your body by making the capillaries of these cells more permeable. Bottom line, the histamine ends up making the blood vessels near the bite swell up. This produces a pink, itchy bump where the mosquito poked you.
Scratching the bump only makes this worse because it causes more irritation and inflammation of the site, resulting in your immune system thinking it needs more antibodies to get rid of the foreign protein. So the more you scratch, the more it will swell; the itchier it will get; and the longer it will last.
Some easy and effective ways to treat mosquito bites to reduce swelling and itchiness include:
Applying a piece of Scotch tape onto the bite and leave it there for a few hours, then gently remove the tape. This will not only help remove some of the saliva that caused the itch, thus speeding up recovery time, but also will reduce the itch significantly in the process.
Apply roll-on antiperspirant to the bite. The itching should stop almost immediately. The aluminum salts in the antiperspirant help the body reabsorb the fluids in the bite, which will reduce the swelling and get rid of most of the itching.