http://www.unknowncountry.com/news/?id=4640

Why do mosquitoes bite some people much more than others? This is merely annoying to those of us living in the West, but to people living in places like Africa, where malaria is rampant, it can mean the difference between life and death. Now scientists have discovered why mosquitoes like some of us much more than others. All humans produce smells which attract these insects, but people who don't get bitten as often produce another smell which masks these scents. If bugs like you, how can you avoid getting bitten? Hang around someone whom the bugs DON'T like to bite.

BBC news reports that researchers want to reporduce this masking smell, because it could be tthe world's most effective mosquito repellant. Scientists have discovered that when herds of cattle contain a large numbers of cows that produce these masking smells, fewer mosquitoes bother the entire herd, even if some of the cows that DO NOT produce this substance.