2006年VOA标准英语-New Field Test Detects Blinding Disease Tr

By David McAlary
Washington
11 May 2006

Scientists have developed a cheap, rapid test to determine who has trachoma, the leading infectious cause of blindness in poor countries. The researchers say the new diagnostic tool is much more accurate than the currently recommended observation method and could help limit expensive treatments to only those who need them.

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Trachoma, once a scourge¹ everywhere, persists in the developing world. Lack of sanitation² and dirty faces invite the organism that inflames³ the lining⁴ of the eyelid⁵ and can lead to blindness if untreated.

The World Health Organization says trachoma affects about 84 million people, blinding about eight million. It has set the year 2020 as the target for elimination⁶.

Part of the elimination strategy includes detection, which requires a trained observer to look under the eyelid for telltale redness and white spots. Although this method is simple and cheap, it lacks precision, especially since the white spots can remain long after the infection is gone. So false diagnoses are common, according to Dr. David Mabey of the London School of Hygiene⁷ and Tropical Medicine.

Dr. David Mabey  
  
"In some communities, you would go on and on giving out antibiotics⁸ long after the infection is gone," said David Mabey. "That clearly is a waste of resources. The thing about trachoma is that it's a disease of the very poorest people in the poorest countries of the world, so the resources are very scarce."

An expensive laboratory test that detects the genes⁹ of the trachoma organism is very accurate, but unaffordable in most places. Now, Mabey and others have developed an accurate but inexpensive chemical test that gives field results in half an hour.

"So the advantage of the new test is it will tell you one way or the other whether infection is present in those communities," he said.

The new technique requires a swab of the inner eyelid and exposes it to a succession of chemicals in two small tubes. If the tested person has trachoma, the liquid in the second tube turns purple in the presence of a dipstick after 25 minutes.

In a trial of more than 600 children in remote Tanzanian villages, the dipstick test was 84 percent accurate in detecting trachoma, compared to 64 percent for the observation method. The false positive diagnoses were less than one percent with the new test, compared to 20 percent for the older method.

"It's measuring what you want to measure," said David Mabey. "Which is, is there infection present in this community?"

The study appears in the journal Lancet. The collaborators say the findings will likely lead to a new approach to trachoma control. But in a Lancet commentary, University of Melbourne doctors Hugh Taylor and Heathcote Wright say more trials are necessary to establish whether the dipstick test will be consistently more reliable than the present observation method.

1 scourge   

n.灾难，祸害；v.蹂躏

参考例句：

• Smallpox was once the scourge of the world.天花曾是世界的大患。
• The new boss was the scourge of the inefficient.新老板来了以后，不称职的人就遭殃了。

2 sanitation   

n.公共卫生，环境卫生，卫生设备

参考例句：

• The location is exceptionally poor,viewed from the sanitation point.从卫生角度来看，这个地段非常糟糕。
• Many illnesses are the result,f inadequate sanitation.许多疾病都来源于不健全的卫生设施。

3 inflames   

v.（使）变红，发怒，过热( inflame的第三人称单数 )

参考例句：

• The Captain inflames the crew with his rhetoric. 船长以他的辩才点燃了船员心中之火。 来自辞典例句
• However, the release of antibodies also inflames the bronchi and bronchioles. 然而，抗体的产生也导致了了支气管和细支气管群的发炎。 来自互联网

4 lining   

n.衬里，衬料

参考例句：

• The lining of my coat is torn.我的外套衬里破了。
• Moss makes an attractive lining to wire baskets.用苔藓垫在铁丝篮里很漂亮。

5 eyelid   

n.眼睑，眼皮

参考例句：

• She lifted one eyelid to see what he was doing.她抬起一只眼皮看看他在做什么。
• My eyelid has been tumid since yesterday.从昨天起，我的眼皮就肿了。

6 elimination   

n.排除，消除，消灭

参考例句：

• Their elimination from the competition was a great surprise.他们在比赛中遭到淘汰是个很大的意外。
• I was eliminated from the 400 metres in the semi-finals.我在400米半决赛中被淘汰。

7 hygiene   

n.健康法，卫生学 （a.hygienic）

参考例句：

• Their course of study includes elementary hygiene and medical theory.他们的课程包括基础卫生学和医疗知识。
• He's going to give us a lecture on public hygiene.他要给我们作关于公共卫生方面的报告。

8 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。

9 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