VOA标准英语2012--Study Links Flu Pandemics to La Ni?a

Study Links Flu Pandemics to La Ni?a

A newly-identified link between pandemic flu and the weather phenomenon known as La Ni?a, may one day permit advance warnings of severe influenza¹ outbreaks.
Most of the time, influenza is a temporary annoyance². But every so often a super flu bug³ comes along, killing⁴ millions and sickening many more.
Jeffrey Shaman, of the Columbia University School of Public Health, notes there were four documented flu pandemics in the past century.
"When we look at those four events, we see that all four of them began directly after a La Ni?a event in the Pacific," he says.
La Ni?a is a periodic cooling of Pacific ocean waters that triggers changes in global weather patterns. Among other things, that altered weather disrupts bird migrations⁵.
Birds can carry flu virus, and when their migratory⁶ patterns change, they can come into contact with other avian species they don't normally meet - birds which might carry a different strain of flu virus.
In the process, the viruses’ genetic⁷ material can get intermingled to create new influenza strains - in a process known as reassortment.
"And it's this reassortment, this creation of new sub-types that takes place - and we think it's in the bird population - that generates, potentially, these pandemic strains that can infect humans and to which most of the world's population will be susceptible," Shaman says.
La Ni?a events happen every few years, and most are not followed by a pandemic. But because the risk of a pandemic appears to increase after a La Ni?a, the next step for researchers is to get a better understanding of how birds and the flu viruses they carry are affected⁸.
One result, Shaman says, may be the ability to improve prediction of an influenza pandemic.
"That's the thing that's exciting about it," he says. "I mean, it offers this sort of tantalizing⁹ possibility that you can say, we have a La Ni?a coming, we need to make these preparations because we know there's an increased likelihood that a pandemic flu strain could arise and infect humans."
But Shaman cautions that more research is needed before that kind of prediction becomes possible. His research paper is published in the Proceedings¹⁰ of the National Academy of Sciences.

1 influenza   

n.流行性感冒，流感

参考例句：

• They took steps to prevent the spread of influenza.他们采取措施
• Influenza is an infectious disease.流感是一种传染病。

2 annoyance   

n.恼怒，生气，烦恼

参考例句：

• Why do you always take your annoyance out on me?为什么你不高兴时总是对我出气？
• I felt annoyance at being teased.我恼恨别人取笑我。

3 bug   

n.虫子；故障；窃听器；vt.纠缠；装窃听器

参考例句：

• There is a bug in the system.系统出了故障。
• The bird caught a bug on the fly.那鸟在飞行中捉住了一只昆虫。

4 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。

5 migrations   

n.迁移，移居( migration的名词复数 )

参考例句：

• It foundered during the turmoils accompanying the Great Migrations. 它在随着民族大迁徙而出现的混乱中崩溃。 来自辞典例句
• Birds also have built-in timepieces which send them off on fall and spring migrations. 鸟类也有天生的时间感应器指导它们秋春迁移。 来自互联网

6 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。

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 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

9 tantalizing   

adj.逗人的；惹弄人的；撩人的；煽情的v.逗弄，引诱，折磨( tantalize的现在分词 )

参考例句：

• This was my first tantalizing glimpse of the islands. 这是我第一眼看见的这些岛屿的动人美景。 来自《简明英汉词典》
• We have only vague and tantalizing glimpses of his power. 我们只能隐隐约约地领略他的威力，的确有一种可望不可及的感觉。 来自英汉非文学 - 历史

10 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼