VOA慢速英语2009-Health Report - New Test Could Speed Tuberculosi

This is the VOA Special English Health Report.

Tuberculosis¹ killed one million three hundred thousand people around the world in two thousand seven. In addition, almost half a million people who were infected with tuberculosis and with H.I.V. also died. Those were listed as H.I.V. deaths.

An estimated one-third of all people are infected with tuberculosis. But the body's natural defenses are usually strong enough to prevent an active case. Even so, the bacteria remain in the body. If the immune system weakens at any point, they begin to spread and then attack.
　
A doctor at a clinic in South Africa looks at a patient's X-ray as part of a TB exam

The bacteria that cause TB usually settle in the lungs. They spread through the air when the person coughs or sneezes or even sings and talks.

One of the most important things is to identify cases quickly -- especially drug-resistant² cases, which are increasing. The patients need to be kept away from other people and begin treatment as soon as possible.

Multidrug resistant tuberculosis, or MDR-TB, will not get better with antibiotics³ normally used for tuberculosis. So doctors must use stronger, "second line" drugs when the first ones fail. Extensively drug-resistant tuberculosis, or XDR-TB, will not respond to any of those drugs but might still be treatable.

Now, researchers say they have found a much faster way to identify drug-resistant TB. The study's lead author is Graham Hatfull at the University of Pittsburgh in Pennsylvania. He says current tests can sometimes take weeks in rural and poor areas of the world. By that time, the patient may already be dead.

The scientists used viruses called bacteriophages to speed the process. These viruses attack bacteria. The researchers injected them with a gene⁴ that produces a green glow of light. They also injected some with first line antibiotics and others with second line drugs.

Then they combined the bacteriophages with TB bacteria. If the bacteria glow, it means they are drug resistant. The researchers say a clinic worker could identify the glow with equipment available in many clinics. Test results would not have to wait for the bacteria to grow in a laboratory far away.

For now, the test itself needs more testing. But Professor Hatfull is hopeful this will take months and not years.

Researchers from the Albert Einstein College of Medicine in New York also took part in the study, financed by the Howard Hughes Medical Institute. The findings appear in the journal PLoS ONE, published by the Public Library of Science.

And that's the VOA Special English Health Report, written by Caty Weaver⁵. I'm Steve Ember.

1 tuberculosis   

n.结核病，肺结核

参考例句：

• People used to go to special health spring to recover from tuberculosis.人们常去温泉疗养胜地治疗肺结核。
• Tuberculosis is a curable disease.肺结核是一种可治愈的病。

2 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。

3 antibiotics   

n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )

参考例句：

• the discovery of antibiotics in the 20th century 20世纪抗生素的发现
• The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。

4 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

5 weaver   

n.织布工；编织者

参考例句：

• She was a fast weaver and the cloth was very good.她织布织得很快，而且布的质量很好。
• The eager weaver did not notice my confusion.热心的纺织工人没有注意到我的狼狈相。