Why do mosquitoes bite

Males of all known species of mosquitoes eat only plant food - pollen and nectar of flowers. They do not trade by sucking blood, only itch nasty. But females without vampirism can not. They don't care who to bite - people or animals.
When the mating period begins, the females tout the males with their characteristic high sound. Mosquitoes catch these sound vibrations with their antennae, choose females and the mating process takes place. After fertilization, the female mosquito needs blood to breed. Even one drop of blood will give life to hundreds of mosquito eggs. And if the blood cannot be found, the females temporarily become vegetarians too, but in this case they can no longer lay eggs.
To suck blood, a mosquito pierces the skin of the victim and, before drinking, inject a substance that prevents blood from clotting. This foreign substance stimulates the victim’s immune system and edema and itching begin to develop around the site of the bite.
What is most unpleasant, mosquitoes not only bite, but also endure various dangerous diseases with bites.Doctors and biologists consider mosquitoes to be the culprits of malaria, which is prevalent mainly in tropical latitudes. Malaria mosquitoes are not much larger than normal. It is possible to distinguish such bloodsuckers by their characteristic fit - their back end is strongly raised up.
The second group of diseases carried by mosquitoes is caused by microscopic filamentous worms. Getting into the bloodstream or lymphatic system, these worms cause blood clots, blockage of blood vessels, accumulation of lymph in the limbs - "elephant disease". Such diseases are common in Africa, Asia and South America. In addition, mosquitoes carry tropical and yellow fever, various encephalitis.
Probably, many noticed that mosquitoes do not even fly to some people. This feature in the people explain the unimportant health of the lucky ones. Insects are often not associated with people who are weakened by a serious illness. Mosquitoes at a distance recognize the quality of blood.