VOA慢速英语20060419b

HEALTH REPORT - Increasing Supplies of Malaria¹ Drug Through Genetic² EngineeringBy Cynthia Kirk

Broadcast: Wednesday, April 19, 2006

I'm Shep O'Neal with the VOA Special English Health Report.

Malaria infects as many as five hundred million people every year. And more than one million people die from the disease each year. Those who do not die become seriously ill.

Southern African countries have the largest number of malaria deaths, mostly among young children. The disease is also common in Asia.

Malaria is caused by a parasite³. Mosquitoes carry the infection from person to person. Researchers say the parasite is becoming increasingly resistant⁴ to older drugs used to treat the disease.




Artemisinin (ar-te-MIS-in-in) is the most effective treatment for malaria and the best drug for treating resistant forms. The World Health Organization says artemisinin should always be used in combination with other drugs to prevent drug resistance.

Artemisinin is made from the sweet wormwood plant found in China and Vietnam. But supplies of the plant are limited. And it takes a lot of plant material to get enough of the drug to treat one patient. Many suppliers are unable to meet the strong demand. The drug is costly⁵ to produce. Each treatment costs more than two dollars. So many people with malaria in developing countries are unable to get the drug. Jay Keasling is a chemical and biological engineer at the University of California at Berkeley. His research team has found a possible solution to the problem. They reported their research in the publication Nature. They placed genes⁶ from the wormwood plant into a yeast⁷ organism and got it to produce large amounts of artemisinic acid. This acid can be made into the drug artemisinin in just a few chemical steps. The researchers say this would end the need for a lot of plants.

Mister Keasling says chemical tests show that the genetically⁸ engineered artemisinin is structurally⁹ the same as the natural form. The new drug must be tested in animals and people to make sure it is safe and effective against malaria.

So the researchers say the drug is still about five to ten years away from final development. They say their findings could reduce the cost of the active substance in artemisinin by ninety percent. This could help save many lives.

This VOA Special English Health Report was written by Cynthia Kirk. Our reports are online at www.unsv.com. I'm Shep O'Neal.

1 malaria   

n.疟疾

参考例句：

• He had frequent attacks of malaria.他常患疟疾。
• Malaria is a kind of serious malady.疟疾是一种严重的疾病。

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 parasite   

n.寄生虫；寄生菌；食客

参考例句：

• The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
• I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。

4 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。

5 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

6 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

7 yeast   

n.酵母；酵母片；泡沫；v.发酵；起泡沫

参考例句：

• Yeast can be used in making beer and bread.酵母可用于酿啤酒和发面包。
• The yeast began to work.酵母开始发酵。

8 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

9 structurally   

在结构上

参考例句：

• The house roof was (structurally) unsound. 这屋顶（结构）不牢固。
• Pinhole on shot-hole damage is never structurally significant. 针孔和蛀洞所造成的危害对结构的影响不大。