VOA常速英语2008年-AIDS Vaccine Testing on Humans Halted Because o

By Melinda Smith
Washington
24 March 2008
 

Scientists who have worked for decades to find a vaccine¹ for the HIV and AIDS infections will meet next week at the U.S. National Institute of Health in Bethesda, Maryland to chart a future course for research.  A few months ago, two human trials of a potential vaccine were halted when it appeared the drug was ineffective, and in some cases, increased the risk of getting the disease.  VOA's Melinda Smith spoke² Friday with Dr. Anthony Fauci, a leading international expert on HIV and AIDS.

Once again, the grim statistics: 12,000 new cases of HIV are diagnosed every day -- more than 25 million people have already died from AIDS.  But the good news is that many more, approximately 40 million people, are still living with HIV.

There has been a great deal of hope pinned on the outcome of two human trials of an HIV vaccine. The STEP trial had just enrolled³ high-risk patients in North and South America, the Caribbean and Australia.  The Phambili trial was just getting underway in South Africa.  To our knowledge, none of the HIV and AIDS patients shown in our video were part of either trial.

It is standard protocol⁴ to have any human trial reviewed by an oversight⁵ committee, which monitors progress and safety.  When the board assigned to monitor these trials looked at the data for the first time, it was obvious that something was not right.

"There was no indication that the vaccine was protecting against infection, and there was no indication that the vaccine was lowering the ultimate level of the virus after one person -- after a person -- got infected," says Doctor Anthony Fauci. Dr. Fauci is Director of Allergy⁶ and Infectious Diseases at the U.S. National Institutes of Health.

The review board was so concerned it recommended that both trials be stopped.  Doctor Fauci says one of the most serious concerns was how the vaccine failed to protect those patients who already seemed to have an underlying⁷ immunity⁸ to a component⁹ of the HIV virus.  That component is an adenovirus [adenovirus vector], found in the common cold.  When those patients were given the vaccine, they had a higher risk of getting infected than those who were not yet vaccinated¹⁰. 

Dr. Fauci says this finding surprised him, "That was surprising.  There was nothing that would have hinted that," he said. 

In the meantime, what can people do who might be at risk for HIV? 

Doctor Fauci says there are many drugs available to help stabilize¹¹ the infection.  For those who are not yet infected, some preventive steps have proven to be highly effective for what is still a highly preventable disease. 

"If you are careful in your sexual contacts, you wear a condom.  If you are an injection drug user, you use clean needles.  If you engage in sex with someone and you don't know what their sexual history is, you use a condom.  In situations, that in certain countries for example, abstinence or delaying sexual debut¹² works (and) in some circumstances, not all -- being faithful to your partner, knowing the HIV history of your partner.  Circumcision has proven to be quite effective to the tune¹³ of about 55 to 65 percent in men in situations who are heterosexually having sex with women.  We're not sure about whether or not it protects among gay men," he said. 

Doctor Fauci says even though the human trials were canceled, there was still valuable information that will be applied¹⁴ when human trials are attempted again.

1 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。

2 spoke   

n.（车轮的）辐条；轮辐；破坏某人的计划；阻挠某人的行动 v.讲，谈（speak的过去式）；说；演说；从某种观点来说

参考例句：

• They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
• The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。

3 enrolled   

adj.入学登记了的v.[亦作enrol]( enroll的过去式和过去分词 )；登记，招收，使入伍（或入会、入学等），参加，成为成员；记入名册；卷起，包起

参考例句：

• They have been studying hard from the moment they enrolled. 从入学时起，他们就一直努力学习。 来自《简明英汉词典》
• He enrolled with an employment agency for a teaching position. 他在职业介绍所登了记以谋求一个教师的职位。 来自《简明英汉词典》

4 protocol   

n.议定书，草约，会谈记录，外交礼节

参考例句：

• We must observe the correct protocol.我们必须遵守应有的礼仪。
• The statesmen signed a protocol.那些政治家签了议定书。

5 oversight   

n.勘漏，失察，疏忽

参考例句：

• I consider this a gross oversight on your part.我把这件事看作是你的一大疏忽。
• Your essay was not marked through an oversight on my part.由于我的疏忽你的文章没有打分。

6 allergy   

n.(因食物、药物等而引起的)过敏症

参考例句：

• He developed an allergy to pollen.他对花粉过敏。
• The patient had an allergy to penicillin.该患者对青霉素过敏。

7 underlying   

adj.在下面的，含蓄的，潜在的

参考例句：

• The underlying theme of the novel is very serious.小说隐含的主题是十分严肃的。
• This word has its underlying meaning.这个单词有它潜在的含义。

8 immunity   

n.优惠；免除；豁免，豁免权

参考例句：

• The law gives public schools immunity from taxation.法律免除公立学校的纳税义务。
• He claims diplomatic immunity to avoid being arrested.他要求外交豁免以便避免被捕。

9 component   

n.组成部分，成分，元件；adj.组成的，合成的

参考例句：

• Each component is carefully checked before assembly.每个零件在装配前都经过仔细检查。
• Blade and handle are the component parts of a knife.刀身和刀柄是一把刀的组成部分。

10 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？

11 stabilize   

vt.（使）稳定，使稳固，使稳定平衡；vi.稳定

参考例句：

• They are eager to stabilize currencies.他们急于稳定货币。
• His blood pressure tended to stabilize.他的血压趋向稳定。

12 debut   

n.首次演出，初次露面

参考例句：

• That same year he made his Broadway debut, playing a suave radio journalist.在那同一年里，他初次在百老汇登台，扮演一个温文而雅的电台记者。
• The actress made her debut in the new comedy.这位演员在那出新喜剧中首次登台演出。

13 tune   

n.调子；和谐，协调；v.调音，调节，调整

参考例句：

• He'd written a tune,and played it to us on the piano.他写了一段曲子，并在钢琴上弹给我们听。
• The boy beat out a tune on a tin can.那男孩在易拉罐上敲出一首曲子。

14 applied   

adj.应用的；v.应用，适用

参考例句：

• She plans to take a course in applied linguistics.她打算学习应用语言学课程。
• This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。