I am no scientist, so don’t take my word for it. Recent events have shown that the tiny mosquito cannot be taken lightly as a carrier of deadly viruses, which have mutated from one host animal or bird to another, and then to mankind, causing grief, great expense and much trouble.
The latest virus which causes Influenza A H1N1 has overshadowed other viruses like, eg. those which cause dengue fever, and the much earlier Malaria. Now, presumably, medical centres in Malaysia do not keep proper records of deaths due to Malaria and the more recent dengue and chikunkunya fever. The national news seems to care about the fatalities due to A H1N1 only.
According to a report which a friend sent me, apparently mosquitoes avoid stressed out people (they do not want your problems, do they?):
(excerpts)
“Besides delivering annoying bites, mosquitoes cause hundreds of millions of cases of disease each year. As many as 500 million cases of malaria are contracted globally each year, and more than one million people die from it, according to the Centers for Disease Control and Prevention. Mosquitoes can also spread West Nile virus, dengue fever, yellow fever and other illnesses.”
Now scientists at Rothamsted Research in the U.K. have been making headway at understanding why some people can end up with dozens of bites after a backyard barbecue, while others remain unscathed. The researchers have identified a handful of the body's chemical odors—some of which may be related to stress—that are present in significantly larger concentrations in people that the bugs are happier to leave alone. If efforts to synthesize these particular chemicals are successful, the result could be an all-natural mosquito repellent that is more effective and safer than products currently available.
"Mosquitoes fly through an aerial soup of chemicals, but can home in on those that draw them to humans," says James Logan, a researcher at Rothamsted, one of the world's oldest agricultural-research institutions. But when the combination of human odors is wrong, he says, "the mosquito fails to recognize this signal as a potential blood meal."
The phenomenon that some people are more prone to mosquito bites than others is well documented. In the 1990s, chemist Ulrich Bernier, now at the U.S. Department of Agriculture's Agricultural Research Service, began looking for what he calls the "magic compounds" that attract mosquitoes. His research helped to show that mosquitoes are attracted to humans by blends of common chemicals such as carbon dioxide, released from the skin and by exhaling, and lactic acid, which is present on the skin, especially when we exercise. But none of the known attractant chemicals explained why mosquitoes preferred some people to others.
Rothamsted's Dr. Logan says the answer isn't to be found in attractant chemicals. He and colleagues observed that everyone produces chemicals that mosquitoes like, but those who are unattractive to mosquitoes produce more of certain chemicals that repel them.
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