Q: Why do mosquito bites itch?
Q: Why do mosquito bites itch?
A: Mosquitoes don’t just poke you with a sharp stick attached to their heads. It’s a mouth they’re sticking underneath your skin, and let’s just say that no one ever told them about backwash.
Female mosquitoes collect blood through their needle-like mouths, but they also leave behind saliva filled with digestive enzymes and anticoagulants, according to author and educator Dr. Alan Greene, proprietor of DrGreene.com and chief medical officer for A.D.A.M., a publisher of interactive health information.
These enzymes and anticoagulants, while useful in keeping the mosquito’s food supply from clotting up, also alert humans to the bug’s presence because they cause chemical damage to the skin, according to Christopher Grayce, a contributor for Argonne National Library’s “Ask a Scientist” program.
“There are beasts that can suck your blood without the process hurting, including leeches and vampire bats,” wrote Grayce. “You’d think that over time, mosquitoes would evolve a painless, anti-clotting spit, so they can drink in peace without alarming you. But, on the other hand, perhaps we have evolved the pain as a warning sign that we are being bitten, and nasty diseases (encephalitis, malaria) may be being transmitted.”
– By Melania Zaharopoulos,
Staff Writer
