DEVELOPMENT REPORT - Malaria Organism

DEVELOPMENT REPORT
–
August 19, 2002: Malaria¹ Organism

By Jill Moss²

This is the VOA Special English Development Report.

Researchers in the United States have discovered that the organism that causes the disease malaria is genetically⁴
more developed, and much older, than earlier thought. Because of this, they say it will be harder to develop
medicines to prevent and treat the deadly disease.

Plasmodium falciparum (plas-MO -dee-um fall-SIP-ah-rum) is the parasite⁵ that
causes the most deadly kind of malaria. Each year, the disease kills more than two-
million people and infects more than two-hundred-million people. In the past,
doctors used the drug chloroquine (KLOR-oh-kwine) to treat malaria. However,
over the past few decades the falciparum parasite has developed resistance to the
medicine.

This resistance to chloroquine was first discovered in parts of South America and
Southeast Asia in the nineteen-fifties. Health experts believed resistance to the drug
then spread to other parts of the world. However, a new study by scientists at the National Institutes of Health
near Washington, D-C, disputes this idea.

The researchers studied the genetic³ structures of eighty -seven falciparum parasites⁶ collected from around the
world. They learned that the parasites had been developing resistance to chloroquine independently in two areas
in South America, one area in Papua New Guinea and one area in Southeast Asia.

In a second study, the scientists examined more than two-hundred genes⁷ from five falciparum parasites. The
parasites were collected in South Asia, Africa, South America, Central America and Papua New Guinea. The
researchers discovered several genetic differences among the parasites. They also learned that the parasites have
been developing separately for at least one-hundred-thousand years.

For several years, scientists have debated when malaria first developed. A few years ago, a genetic study of
falciparum parasites found the disease to be between three-thousand and five -thousand years old. The study also
found the parasites to be genetically similar. This latest research disputes those results.

Xin-zhuan Su (sin -schwan soo) led the two studies published last month in the publication Nature. He says that
new treatments to fight malaria may be possible as scientists learn more about the history of the falciparum
parasite.

This VOA Special English Development Report was written by Jill Moss.

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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 moss   

n.苔，藓，地衣

参考例句：

• Moss grows on a rock.苔藓生在石头上。
• He was found asleep on a pillow of leaves and moss.有人看见他枕着树叶和苔藓睡着了。

3 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。

4 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

5 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。

6 parasites   

寄生物( parasite的名词复数 )； 靠他人为生的人； 诸虫

参考例句：

• These symptoms may be referable to virus infection rather than parasites. 这些症状也许是由病毒感染引起的，而与寄生虫无关。
• Kangaroos harbor a vast range of parasites. 袋鼠身上有各种各样的寄生虫。

7 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