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Researchers Work on Malaria-Resistant Mosquitoes

andyg 于2007-07-01发布 l 已有人浏览
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&raquo Download Audio(mp3) By Nancy Steinbach 2007-7-1 This is the VOA Special English Development Repo

» download audio(mp3)
by nancy steinbach
2007-7-1

this is the voa special english development report.

scientists say they have made more progress in developing malaria-resistant mosquitoes. the idea is to release genetically engineered insects like these into mosquito populations as a way to control the disease.

malaria is spread by mosquitoes

each year more than three million people become infected with malaria. at least one million die, mostly young children and pregnant women in africa. malaria is also a problem in asia and south america.

the parasites that cause malaria enter people's blood when they are bitten by the mosquitoes that carry the organisms. the parasites travel to the liver where they divide and grow. after a week or two, they invade red blood cells and reproduce thousands of times. they can destroy major organs.

people die from malaria because they are not treated or treatment is delayed. drugs can prevent the parasites from developing in the body. but experts still say the best way to prevent malaria is not to be bitten by a mosquito.

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