VOA慢速英语 2008 1027a

This is the VOA Special English Development Report.

An estimated one-third of all people are infected with tuberculosis¹. Most have latent, or inactive, cases. They do not suffer coughing, increased body temperature or other signs of active TB.
　

A tuberculosis patient looks at a TB awareness2 poster in a 2007 photo

But each year, about nine million people develop active cases and two million die. TB is an ancient bacterial³ disease. It can be cured with antibiotics⁴, if patients take all their medicine. The victims, though, are mostly poor and live in developing countries.

Now, scientists have reported two new developments in tuberculosis research.

For the past century, a skin test has been the traditional way to identify latent TB. When cases are found, treatment can prevent many from becoming active. But the preventive drugs have a risk of side effects.

The skin test depends on the body's reaction to an injection of specially⁵ prepared TB protein. But the test often falsely identifies people as having latent TB if they have been vaccinated⁶ against the disease.

To avoid needless treatment, scientists have developed a blood test. This test is designed to identify patients with a high risk of developing the active form of TB.

Ajit Lalvani from Imperial College London led an international team in developing the blood test, called ELISpot (EL-ee spot). A study showed that the ELISpot blood test identifies latent TB while giving fewer false positive results.

The researchers say the ELISpot test has been recommended for use in about twenty countries worldwide. A report on the new blood test appeared last week in the Annals of Internal Medicine.

In another development, scientists have reported a step toward a better vaccine⁷ against TB. One currently used is seventy-five years old.

The new experimental vaccine contains a weakened TB bacterium⁸ from a strain of the current vaccine. The scientists say that in their study, the experimental vaccine created stronger responses against TB than the traditional one.

But the new vaccine contains an antibiotic-resistant gene⁹ that the scientists do not want released into the environment. So the vaccine will not be tested further. But research will continue on a similar one that does not contain the gene.

Daniel Hoft of the Saint Louis University School of Medicine in Missouri was lead author of a report in the Journal of Infectious Diseases.

And that's the VOA Special English Development Report. It was written by Jerilyn Watson.

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 awareness   

n.意识，觉悟，懂事，明智

参考例句：

• There is a general awareness that smoking is harmful.人们普遍认识到吸烟有害健康。
• Environmental awareness has increased over the years.这些年来人们的环境意识增强了。

3 bacterial   

a.细菌的

参考例句：

• Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
• Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

4 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。

5 specially   

adv.特定地；特殊地；明确地

参考例句：

• They are specially packaged so that they stack easily.它们经过特别包装以便于堆放。
• The machine was designed specially for demolishing old buildings.这种机器是专为拆毁旧楼房而设计的。

6 vaccinated   

[医]已接种的，种痘的，接种过疫菌的

参考例句：

• I was vaccinated against tetanus. 我接种了破伤风疫苗。
• Were you vaccinated against smallpox as a child? 你小时候打过天花疫苗吗？

7 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。

8 bacterium   

n.(pl.)bacteria 细菌

参考例句：

• The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。
• A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。

9 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。