VOA慢速英语2009年-Development Report - Looking for New W

This is the VOA Special English Development Report.

Scientists are studying ways to make mosquitoes resist malaria¹-causing parasites³

Scientists continue to seek better weapons against malaria. Each year the number of cases is in the hundreds of millions worldwide. Around a million people die, most of them in Africa. Economic losses from the disease amount to an estimated one percent of the African economy each year.

George Dimopoulos is an associate professor at the Johns Hopkins Malaria Research Institute in Baltimore, Maryland.

GEORGE DIMOPOULOS: "Forty-two percent of the earth's population live in areas where malaria transmitting mosquitoes exist. All of these people are in risk of being infected with malaria. The sad thing is that the majority of people that are killed by malaria are children because there immune system is not strong enough to ward⁴ off this infection."

Malaria is caused by a parasite² called Plasmodium. The organism is injected into people through the bite of infected mosquitoes. Malaria can be treated, but in many areas the parasites have become resistant⁵ to different drugs.

George Dimopoulos and his team are studying ways to make mosquitoes resist infection by the parasite. There are hundreds of kinds of mosquitoes in the world. Most do not spread malaria. Some have immune systems that kill Plasmodium.

GEORGE DIMOPOULOS: "We are particularly interested in these type of immune reactions that are responsible for killing⁶ the malaria parasite. Because we think once we understand how they work, we could be able to manipulate the mosquito genetically⁸ and convert mosquitoes that can transmit malaria into mosquitoes that cannot transmit malaria."

The researchers have developed a way to make genetic⁷ changes in the three mosquito species known to spread malaria. The changes cause their systems to attack the parasite, blocking its development. Other researchers are working on ways to spread these genetically modified insects among mosquito populations.

Professor Dimopoulos says there is still a long way to go, but current malaria research is highly promising⁹.

A new vaccine¹⁰ is in final testing. So far it has proven effective at preventing the disease in half of those vaccinated¹¹ -- which is more than ever before.

And at the Malaria Institute at Macha in Zambia, researchers are developing an easier way to identify malaria. The test uses saliva¹² instead of blood to diagnose the infection.

Current efforts in malaria control are mainly based on the use of insecticide sprays and treated bed nets. But George Dimopoulos says malaria needs to be attacked with drugs, with vaccines¹³, with bed nets -- with whatever researchers can find.

GEORGE DIMOPOULOS: "Malaria needs to be attacked with multiple weapons. There is not one magic bullet to control this disease."

And that's the VOA Special English Development Report, written by June Simms. Transcripts¹⁴ and MP3s of our reports are at voaspecialenglish.com. I'm Steve Ember.

 

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 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。

3 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。

4 ward   

n.守卫，监护，病房，行政区，由监护人或法院保护的人（尤指儿童）；vt.守护，躲开

参考例句：

• The hospital has a medical ward and a surgical ward.这家医院有内科病房和外科病房。
• During the evening picnic,I'll carry a torch to ward off the bugs.傍晚野餐时，我要点根火把，抵挡蚊虫。

5 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。

6 killing   

n.巨额利润；突然赚大钱，发大财

参考例句：

• Investors are set to make a killing from the sell-off.投资者准备清仓以便大赚一笔。
• Last week my brother made a killing on Wall Street.上个周我兄弟在华尔街赚了一大笔。

7 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。

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 promising   

adj.有希望的，有前途的

参考例句：

• The results of the experiments are very promising.实验的结果充满了希望。
• We're trying to bring along one or two promising young swimmers.我们正设法培养出一两名有前途的年轻游泳选手。

10 vaccine   

n.牛痘苗，疫苗；adj.牛痘的，疫苗的

参考例句：

• The polio vaccine has saved millions of lives.脊髓灰质炎疫苗挽救了数以百万计的生命。
• She takes a vaccine against influenza every fall.她每年秋季接种流感疫苗。

11 vaccinated   

[医]已接种的，种痘的，接种过疫菌的

参考例句：

• I was vaccinated against tetanus. 我接种了破伤风疫苗。
• Were you vaccinated against smallpox as a child? 你小时候打过天花疫苗吗？

12 saliva   

n.唾液，口水

参考例句：

• He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
• Saliva dribbled from the baby's mouth.唾液从婴儿的嘴里流了出来。

13 vaccines   

疫苗，痘苗( vaccine的名词复数 )

参考例句：

• His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
• The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。

14 transcripts   

n.抄本（ transcript的名词复数 ）；转写本；文字本；副本

参考例句：

• Like mRNA, both tRNA and rRNA are transcripts of chromosomal DNA. tRNA及rRNA同mRNA一样，都是染色体DNA的转录产物。 来自辞典例句
• You can't take the transfer students'exam without your transcripts. 没有成绩证明书，你就不能参加转学考试。 来自辞典例句