Why mosquitoes are after us?

This is with reference to the report “Dengue outbreak feared in Jeddah” (Nov. 26). One wonders how such a small insect can cause panic among people.
According to scientific studies, a chemical vapor exuded from human skin is the key reason why mosquitoes turn from feeding on animals to sucking human blood. Sulcatone is an important ingredient in the distinctive human odor. Mosquitoes, according to scientists, learned to recognize it many thousands years ago as a sign that they were near a source of food.
Researchers found that the present-day black-bodied mosquitoes that feed on the furry skin of forest animals do not show any preference for sulcatone, but the brown mosquitoes living in and around villages in Africa are highly attracted to the scent. These mosquitoes have evolved to love the way we smell like the way we humans respond to the aromas of “kabsa” or “biryani.”
Anyway, we provide the ideal lifestyle for mosquitoes. We always have pools of water in our streets for them to breed in and we live in large groups. Some of the familiar diseases mosquitoes usually spread are malaria, Chikungunya, yellow fever and dengue against which many countries in Asia have declared war. Dengue is a serious arboviral disease of the Americas, Asia and Africa. It has very uncomfortable symptoms and has become more serious both in frequency and mortality in recent years. — S.H. Moulana, Riyadh