VOA慢速英语2011--The Long Search for a Malaria Vaccine

Health Report - The Long Search for a Malaria¹ Vaccine²

 

健康报道 - 疟疾疫苗的长期攻坚之旅

This is the VOA Special English Health Report.

这里是美国之音慢速英语健康报道。

Malaria control efforts currently depend on things like chemically treated bed nets and spraying against mosquitoes. But scientists keep trying to find other ways to prevent the disease.

当前疟疾控制主要依赖于消毒蚊帐和喷药灭蚊等措施。但科学家一直在尝试寻找其它途径来预防疟疾。

A number of vaccines³ remain under development. Most contain genetically⁴ engineered versions of a few proteins from the Plasmodium parasite⁵. Plasmodium is the organism that causes malaria. Those modified proteins are designed to get the body's defenses to launch an immune response against the Plasmodium. But the parasite contains thousands of proteins.

大量疫苗仍在研发阶段，其中多数包含疟原虫部分蛋白质的转基因版本。疟原虫是导致疟疾的生物体。这些改良过的蛋白质的作用是让人体免疫系统对疟原虫做出免疫反应。但这种寄生虫包含数千种蛋白质。

Another experimental vaccine includes a deactivated⁶ version of the entire parasite. Robert Seder is a researcher at the National Institute of Allergy⁸ and Infectious Diseases, near Washington.

另一种实验性疫苗包含整个寄生虫（蛋白质）的无活力版本。Robert Seder是华盛顿附近的美国过敏与传染病研究所的一名研究员。

ROBERT SEDER: "So instead of picking out one or two or three genes⁹, you have the potential for what we call breadth -- generating an immune response that would be broad rather than narrower. And so that would be a good thing."

ROBERT SEDER：“所以我们不是挑选出两三种基因，而是拥有广度的潜能，能够产生广泛免疫反应。所以这将是一个好消息。”

Radiation is used to weaken the parasite so it cannot make people sick or get spread by a mosquito. To make the vaccine, scientists use the parasite at a time in its growth when the organism is called a sporozoite.

辐射被用于削弱寄生虫，使其不能致病或通过蚊虫传播。为了制造这种疫苗，科学家使用了在其生长过程中被称为孢子虫阶段的寄生虫。

A child suffering from malaria sleeps under a mosquito net while a mother feeds her child, also suffering from malaria, at a hospital in Kenya in 2009

This idea has been known since the nineteen sixties. But Mr. Seder says a discovery by a researcher at a vaccine company cleared the way for progress.

这个想法自上世纪60年代以来就被人熟知。但Seder先生表示，一位疫苗公司研究人员的发现为这一进程扫清了障碍。

ROBERT SEDER: "The major breakthrough here was that my collaborator¹⁰, Stephen Hoffman at Sanaria, developed a method where he could isolate¹¹ the sporozoites and purify them so that they could administer it as a vaccine to humans. And no one thought that that was possible."

ROBERT SEDER：“这一重大突破是我的合作者，来自Sanaria公司的Stephen Hoffman研制出的一种新方法。在这种新方法中，他可以隔离孢子虫并将其净化，这样他们可以将其用于人类疫苗。此前没人认为这是可能的。”

But no one knew either if the weakened sporozoites would activate⁷ the immune system to protect against malaria. So researchers tested it on volunteers and found that it was safe -- there were only minor¹² side effects. But it was not very effective. Only two out of forty-four volunteers were protected when bitten by malaria-infected mosquitoes.

但也没有人知道，这种弱化孢子虫是否会激活免疫系统以预防疟疾。因此，研究人员在志愿者身上进行了测试，并发现它是安全的，但不是非常有效。44名志愿者中，只有2人在被疟疾感染蚊虫叮咬时得到了预防。

To find out why, the researchers tested the vaccine on laboratory animals. They decided¹³ that the problem was the way the vaccine had been given to the volunteers. It was injected into the skin, to simulate the bite of a mosquito. Mr. Seder says it would have been more effective if it had been given directly into the blood.

为了找出原因，研究人员在实验室动物身上对疫苗进行了测试。他们认为问题出在给志愿者注射疫苗的方式上，疫苗是模拟蚊虫叮咬被注入皮肤。Seder先生表示，如果疫苗直接注入血液会更加有效。

However, vaccines are generally given by mouth or injected into the skin or muscle. Having to inject it into the blood could make vaccination¹⁴ programs more difficult if the vaccine is approved for general use. Mr. Seder says it is also too soon to know how much the vaccine would cost.

然而，疫苗通常是口服或注射到皮肤或肌肉。如果疫苗被批准使用，注入血液会使疫苗接种程序更为困难。

For now, more testing is needed. A report on the study appeared in the journal Science.

现在需要进行更多测试。研究报告发表在《科学》杂志上。

And that’s the VOA Special English Health Report. You can find more stories about the fight against malaria at voanews.cn. I'm Steve Ember.
___

Contributing: Art Chimes

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 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。

3 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。

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 deactivated   

v.解除动员( deactivate的过去式和过去分词 )；使无效；复员；使不活动

参考例句：

• \"The brain can be deactivated. It can be yours to command.\" “大脑计算机可以被停止。如果你下达命令的话。” 来自互联网
• He successfully deactivated a nuclear reactor in a laboratory before meltdown. 他成功停用一个核反应堆在实验室之前崩溃。 来自互联网

7 activate   

vt.使活动起来，使开始起作用

参考例句：

• We must activate the youth to study.我们要激励青年去学习。
• These push buttons can activate the elevator.这些按钮能启动电梯。

8 allergy   

n.(因食物、药物等而引起的)过敏症

参考例句：

• He developed an allergy to pollen.他对花粉过敏。
• The patient had an allergy to penicillin.该患者对青霉素过敏。

9 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

10 collaborator   

n.合作者，协作者

参考例句：

• I need a collaborator to help me. 我需要个人跟我合作，帮我的忙。
• His collaborator, Hooke, was of a different opinion. 他的合作者霍克持有不同的看法。

11 isolate   

vt.使孤立，隔离

参考例句：

• Do not isolate yourself from others.不要把自己孤立起来。
• We should never isolate ourselves from the masses.我们永远不能脱离群众。

12 minor   

adj.较小(少)的，较次要的；n.辅修学科；vi.辅修

参考例句：

• The young actor was given a minor part in the new play.年轻的男演员在这出新戏里被分派担任一个小角色。
• I gave him a minor share of my wealth.我把小部分财产给了他。

13 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

14 vaccination   

n.接种疫苗，种痘

参考例句：

• Vaccination is a preventive against smallpox.种痘是预防天花的方法。
• Doctors suggest getting a tetanus vaccination every ten years.医生建议每十年注射一次破伤风疫苗。