Why do mosquito bites itch?

Answer 1

When a mosquito bites, it injects some of its saliva into the victim.
The saliva contains an anti-coagulant to help the mosquito suck up blood.
The saliva also contains germs and such that cause a mild localized infection that causes
the itching.

Answer 2

Contrary to whats asked in the question and what people have stated, mosquitoes dont actually bite. Rather they suck the blood from humans. Though referring to this as a bite has been the accepted description of this action.The blood is required for a biological reason, that is to provide protein for necessary egg production.
The mosquitoe is actually quite a deadly insect due to the many disease it can carry, some species of mosquitoe carrying the Malaria parasite, malaria being responsible for millions of deaths world wide each year. Reassuringly for the world, AIDS cannot be transmitted through the mosquitoe bite as the virus that causes AIDS is unable to survive inside a mosquitoe.
The Itch is caused by the mosquitoes salivas as it goes about stealing our blood, This saliva causes an allergic reaction, unfortunately for some this can be more severe than for other people.

Answer 3

When the mosquito stabs her needle-like mouthparts through the skin of her victim, she injects her saliva -- teeming with digestive enzymes and anticoagulants. The first time a person is bitten, there is no reaction. With subsequent bites, the person becomes sensitized to the foreign proteins, and small, itchy, red bumps appear about 24 hours later. This is the most common reaction in young children. After many more bites, a pale, swollen hive, or wheal, begins to appear within minutes after a bite -- followed by the red bump 24 hours later. This is the most common reaction in older children and adolescents.

With repeated mosquito bites, some people begin to become insensitive again, much as if they had allergy shots. Some older children and adults get no reaction to mosquito bites (unless they go for a long time without being bitten -- then the process can start again). Other people become increasingly allergic with repeated stings. They can develop blistering, bruised, large inflammatory reactions. For these people, avoiding being bitten is a particularly good idea.

Answer 4

Because as they insert their stylets in your skin they regurgitate saliva. Researches have found many important substances in their saliva, most of them help the mosquito in one way or the other. For example some substances dilate (or make bigger) the capillaries so they can more easily extract your precious blood. Some others are anesthesic (so you don't feel de bite) and yet others are anticoagulant (so the flow of blood is quick and uninterrupted) allowing them to suck your blood before you kill them. Some cells in your skin belong to the Immune System (Langerhan cells and others), when they come in contact with foreign molecules (substances) in the mosquito's saliva they react quickly and present this substances to effector cells that proke an acute inflammatory response with redness, swelling, itching, and warmth. It is a normal reaction of your skin and an attempt to heal the stupid mosquito bite.

Answer 5

This Site Might Help You.

RE:
Why do mosquito bites itch?

Answer 6

The notion that mosquitos spread AIDS is spurious to say the least... which is not to say that it doesn't happen: it hasn't been proved one way or the other.

It is the female anopheles mosquito which is blamed for spreading malaria. Having spent some time (six-seven months) in Papua New Guinea and been bitten by some of the most exotic mosquitos in the world, I'm still in one piece. At the time (1970s), venereal disease was rife, just as it was with returning Viet vets.

Trust me, not many of us contracted STDs from toilet seats.

It ain't the mosquito. STDs remain exactly that - and spread specifically through the sharing of bodily fluids.

'Mozzies' do not share blood-donors... they just make an infuriating swelling which itches like crazy.

And wait until you're asleep... and buzzzzzz...

Paul

Answer 7

In short, your body reacts to what the mosquito injects through the skin and you mound a small immune response. This releases a chemical named 'histamine' which irritates nerve endings and makes you itch.
This is the basis for antihistamine medicines working.
Regarding whether HIV can be spread through mossie bites - my understanding is that the virus cannot survive inside a mossie, and thus there is 0% chance of transmission.
It is well proven however that some tropical diseases are transmitted via mossie such as malaria, dengue fever & japanese encephalitis.
Hope this helps,

Answer 8

Itching of this sort is caused by the fight being waged beneath your skin between your body's defenses and the various things the mosquito introduces. Itching is a good sign, it means that your body is winning the war, if it wasn't, it would hurt instead of itch.

It is also the skin healing itself and the area returning to normal, much like a cut can itch as it heals.

Answer 9

Mosquito bites itch because when they bite you, they inject a poison that irritates your skin and makes it itch. I think it affects some people worse than others, but that's just a theory.

Answer 10

Your body is reacting to the bite of a mosquito with a mild allergic reation. If you have a ton of bites an antihistamine will help.
PS. People who say mosquitos don't bother them are actually still being bitten their bodies just don't treat the bite as an allergan.