VOA标准英语2011--WHO Says TB Blood Test Inaccurate

WHO Says TB Blood Test Inaccurate¹

The World Health Organization is urging many low and middle income countries to ban the use of currently-available commercial blood tests to detect active tuberculosis². This is the first time WHO has issued an explicit³ negative policy recommendation against a practice widely used in tuberculosis care. It is based on two recent studies that found the commonly-used test to be unreliable and misleading -- and even a possible contributor to TB transmission.
Tuberculosis kills 1.7 million people a year, around the world. In India, where the blood tests covered by the recommendation are widely used, the government says more than two million new people are infected every year.
In fact, the studies that prompted the WHO action were done in India, where researchers argued the blood tests have contributed to increasing the number of TB infections in the country.
They blamed the inaccuracy of the test for this outcome, saying an undetected, and untreated, case means the infected person can continue to infect others.
Dr. David Dowdy⁴ of the Johns Hopkins School of Public Health was a lead researcher in one of the two studies.
“These tests are actively⁵ doing people harm by causing them either to take medicines that they don’t need or delaying the diagnosis⁶ that they actually do need to get better,” Dowdy said.
Dowdy says that the traditional sputum smear⁷ microscopy test is still the cheapest and most effective way of diagnosing TB.
But since the sputum test is time-consuming, he says, the blood tests are often preferred because they are simple, straightforward⁸ and quicker to run.
Experts also say the blood tests are a multimillion dollar business in developing countries. The WHO says more than a million of the tests are carried out each year, even though they are not approved by any recognized regulatory body.
“What these tests do is they measure antibodies in the blood against TB so any time anyone has been infected with TB at any time in their life they will develop antibodies against TB. But the problem is that one person’s antibodies are not going to be the same as the other person. And we don’t have a test yet that can detect antibodies across the board,” Dowdy said.
After the WHO issued its guidelines, the Indian government issued a statement urging doctors and labs not to rely on these imprecise diagnostic tests.
It may take some time, though, before the realities on the ground change in a country as vast as India.
However, experts in the field have welcomed the WHO announcement and the Indian government's response.

1 inaccurate   

adj.错误的，不正确的，不准确的

参考例句：

• The book is both inaccurate and exaggerated.这本书不但不准确，而且夸大其词。
• She never knows the right time because her watch is inaccurate.她从来不知道准确的时间因为她的表不准。

2 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。

3 explicit   

adj.详述的，明确的；坦率的；显然的

参考例句：

• She was quite explicit about why she left.她对自己离去的原因直言不讳。
• He avoids the explicit answer to us.他避免给我们明确的回答。

4 dowdy   

adj.不整洁的；过旧的

参考例句：

• She was in a dowdy blue frock.她穿了件不大洁净的蓝上衣。
• She looked very plain and dowdy.她长得非常普通，衣也过时。

5 actively   

adv.积极地，勤奋地

参考例句：

• During this period all the students were actively participating.在这节课中所有的学生都积极参加。
• We are actively intervening to settle a quarrel.我们正在积极调解争执。

6 diagnosis   

n.诊断，诊断结果，调查分析，判断

参考例句：

• His symptoms gave no obvious pointer to a possible diagnosis.他的症状无法作出明确的诊断。
• The engineer made a complete diagnosis of the bridge's collapse.工程师对桥的倒塌做一次彻底的调查分析。

7 smear   

v.涂抹；诽谤，玷污；n.污点；诽谤，污蔑

参考例句：

• He has been spreading false stories in an attempt to smear us.他一直在散布谎言企图诽谤我们。
• There's a smear on your shirt.你衬衫上有个污点。

8 straightforward   

adj.正直的，坦率的；易懂的，简单的

参考例句：

• A straightforward talk is better than a flowery speech.巧言不如直说。
• I must insist on your giving me a straightforward answer.我一定要你给我一个直截了当的回答。