美国国家公共电台 NPR A Few Genetic Tweaks To Chinese Bird Flu Virus Could Fuel A Human Pandemic

 

AUDIE CORNISH, HOST:

Public health officials are increasingly worried about a strain of bird flu virus that's circulating in China. In the last nine months it's sickened more than 700 people, and about 40 percent of them died. Now a team of researchers from the U.S. and the Netherlands has new information on what might cause this virus to start spreading more widely. NPR's Nell Greenfieldboyce reports.

NELL GREENFIELDBOYCE, BYLINE¹: Right now people seem to get the H7N9 bird flu virus from, well, birds. It isn't capable of spreading from person to person to person to person. But what if that changed?

JAMES PAULSON: We're trying to just understand the virus so that we can be prepared.

GREENFIELDBOYCE: Jim Paulson is a biologist at the Scripps Research Institute. He and some colleagues recently tinkered with a piece of this bird flu, a protein that lets the virus latch² on to cells.

PAULSON: So it's not the whole virus. It's just a fragment that we can then study for its properties.

GREENFIELDBOYCE: They found that it only takes three little changes to make this protein capable of hooking on to human cells. That could help the virus start spreading between people, although Paulson cautions that other changes might be necessary.

PAULSON: There may be several other genes³ that are important for transmission that we don't know about.

GREENFIELDBOYCE: Now, one way of finding out would be to make those three changes in the actual virus in a highly secure lab and see what happens. Does it become contagious⁴ in lab animals? Well, scientists like Paulson can't do that experiment because in 2014 the Obama administration stopped all federally funded work that might make flu viruses more dangerous. That's because critics argued that scientists shouldn't be in the business of deliberately⁵ making deadly flu viruses even worse. What if a lab-made virus escaped or got stolen for use as a bioweapon?

PAULSON: I admit that - you know, that some people have real reservations about it. I mean, these are all legitimate⁶ concerns, in my view.

GREENFIELDBOYCE: That's why Paulson wants to test these mutations not in the deadly H7N9 bird flu virus itself but rather in a weakened flu virus. And that may soon be possible. Government officials are drafting a new system for how they'll review flu experiments to decide what can go forward. Carrie Wolinetz is associate director for science policy at the National Institutes of Health, which funds flu research. She says once that policy is finished the moratorium⁷ will be lifted.

CARRIE WOLINETZ: Our expectation is it will be very soon.

GREENFIELDBOYCE: It's not clear what exactly will be permitted under the new policy. And after years of debate, it seems like scientists still have reached no consensus⁸ on how to balance the risks and the benefits. David Relman is a biologist at Stanford University. He'd be OK with putting these mutations in a weakened virus, but putting them in the H7N9 virus...

DAVID RELMAN: I would be very hesitant to see them do that experiment and try it out.

GREENFIELDBOYCE: Other scientists say we have to experiment with H7N9. Ron Fouchier is a virologist at Erasmus Medical Center in the Netherlands who studies flu with U.S. funding. He says at the end of the day you need to alter the real flu virus you're worried about to know what it's really capable of. He thinks U.S. officials will agree. But even if they don't...

RON FOUCHIER: The rest of the world is moving forward with this type of experiment already. And so the U.S. can either join or not join. It's up to them. But the work will continue.

GREENFIELDBOYCE: He hopes that officials will reveal more about their plans when federally funded flu researchers meet next month in Atlanta. Nell Greenfieldboyce, NPR News.

(SOUNDBITE OF COLD CAVE SONG, "LOVE COMES CLOSE")

1 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

2 latch   

n.门闩，窗闩；弹簧锁

参考例句：

• She laid her hand on the latch of the door.她把手放在门闩上。
• The repairman installed an iron latch on the door.修理工在门上安了铁门闩。

3 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

4 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。

5 deliberately   

adv.审慎地；蓄意地；故意地

参考例句：

• The girl gave the show away deliberately.女孩故意泄露秘密。
• They deliberately shifted off the argument.他们故意回避这个论点。

6 legitimate   

adj.合法的，合理的，合乎逻辑的；v.使合法

参考例句：

• Sickness is a legitimate reason for asking for leave.生病是请假的一个正当的理由。
• That's a perfectly legitimate fear.怀有这种恐惧完全在情理之中。

7 moratorium   

n.(行动、活动的)暂停(期)，延期偿付

参考例句：

• The government has called for a moratorium on weapons testing.政府已要求暂停武器试验。
• We recommended a moratorium on two particular kinds of experiments.我们建议暂禁两种特殊的实验。

8 consensus   

n.(意见等的)一致，一致同意，共识

参考例句：

• Can we reach a consensus on this issue?我们能在这个问题上取得一致意见吗？
• What is the consensus of opinion at the afternoon meeting?下午会议上一致的意见是什么？