2006年VOA标准英语-Scientists Develop Possible Bird Flu Vaccine Us

By Deborah Block
Washington, D.C.
26 June 2006
 
watch Bird Flu report

Researchers are working on developing vaccines² for bird flu before it becomes a worldwide epidemic³.  The University of Massachusetts Medical School in the United States has teamed with a British drug company to come up with a potential vaccine¹ using bird flu DNA⁴. 

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Bird Flu Virus   
  
Traditional flu vaccines use weakened flu viruses and take months to produce on a large scale.

The bird flu DNA vaccine could be easily duplicated and produced in large quantities.  DNA is a molecule⁵ found in a cell that contains a specific genetic⁶ blueprint⁷.  The DNA-based vaccine would be inserted using a pressurized gun that penetrates⁸ the skin without using needles.  

So far, it appears the bird flu virus has spread only to people who handle poultry⁹ or have eaten contaminated meat.  It has killed more than 125 people worldwide, as well as large poultry flocks in Asia, Europe and Africa.  Experts fear millions of people could die in the future if the virus combines with human flu strains and produces a new strain that is highly contagious¹⁰ to people.

Dr. Shan Lu  
  
Dr. Shan Lu is with the University of Massachusetts Medical School. "Clearly the bird flu is spreading to more places. The question is when they will jump to humans.  That is the question we don't know, but we have to prepare."

Researchers are trying to figure out how the tiny organism replicates¹¹, so it can be stopped from spreading.  Waterfowl and other migratory¹² birds can tolerate the organism, secreting¹³ it as waste into ponds, lakes and rivers.  But the virus becomes deadly to humans when it infects birds that live on land, particularly chickens.  Right now the only way to control bird flu is to slaughter¹⁴ diseased poultry.

 
Daniel Perez 
  
Daniel Perez is head of a bird flu research program at the University of Maryland.  He is unsure whether the vaccine, if proven effective, would stop a worldwide epidemic since bird flu viruses mutate, changing constantly. 

"The virus is completely unpredictable.  I think one of the biggest questions would be how many doses we have to make, how soon we have to have them, because if it [an epidemic] happens tomorrow, we don't have them," warns Mr. Perez.

The vaccine will be tested on animals soon. Human trials are expected in about six months.

1 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。

2 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。

3 epidemic   

n.流行病；盛行；adj.流行性的，流传极广的

参考例句：

• That kind of epidemic disease has long been stamped out.那种传染病早已绝迹。
• The authorities tried to localise the epidemic.当局试图把流行病限制在局部范围。

4 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

5 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

6 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。

7 blueprint   

n.蓝图，设计图，计划；vt.制成蓝图，计划

参考例句：

• All the machine parts on a blueprint must answer each other.设计图上所有的机器部件都应互相配合。
• The documents contain a blueprint for a nuclear device.文件内附有一张核装置的设计蓝图。

8 penetrates   

v.穿过( penetrate的第三人称单数 )；刺入；了解；渗透

参考例句：

• This is a telescope that penetrates to the remote parts of the universe. 这是一架能看到宇宙中遥远地方的望远镜。 来自《简明英汉词典》
• The dust is so fine that it easily penetrates all the buildings. 尘土极细，能极轻易地钻入一切建筑物。 来自辞典例句

9 poultry   

n.家禽，禽肉

参考例句：

• There is not much poultry in the shops. 商店里禽肉不太多。
• What do you feed the poultry on? 你们用什么饲料喂养家禽?

10 contagious   

adj.传染性的，有感染力的

参考例句：

• It's a highly contagious infection.这种病极易传染。
• He's got a contagious laugh.他的笑富有感染力。

11 replicates   

复制( replicate的第三人称单数 )； 重复； 再造； 再生

参考例句：

• The bluetongue virus replicates in the insect. 蓝舌病病毒在这种昆虫体内繁殖。
• The chameleon's skin replicates the pattern of its surroundings. 变色龙的皮肤可随环境的模式而改变颜色。

12 migratory   

n.候鸟，迁移

参考例句：

• Many migratory birds visit this lake annually.许多候鸟每年到这个湖上作短期逗留。
• This does not negate the idea of migratory aptitude.这并没有否定迁移能力这一概念。

13 secreting   

v.（尤指动物或植物器官）分泌( secrete的现在分词 )；隐匿，隐藏

参考例句：

• It is also an endocrine gland secreting at least two important hormones. 它也是一种内分泌腺，至少分泌二种重要的激素。 来自辞典例句
• And some calcite-secreting organisms also add magnesium to the mix. 有些分泌方解石的生物，会在分泌物中加入镁。 来自互联网

14 slaughter   

n.屠杀，屠宰；vt.屠杀，宰杀

参考例句：

• I couldn't stand to watch them slaughter the cattle.我不忍看他们宰牛。
• Wholesale slaughter was carried out in the name of progress.大规模的屠杀在维护进步的名义下进行。