VOA标准英语2015--Studies Support Truvada as Prevention

Studies Support Truvada as Prevention

New studies show programs that use antiretroviral drugs to prevent HIV infection are very effective. The findings were released at the Conference on Retroviruses and Opportunistic Infections in Seattle, Washington. (2/23-2/26)

Using HIV-suppressing drugs as a prevention method is called PrEP or pre-exposure prophylaxis. Supporters say it’s a powerful tool to help stop the spread of the AIDS virus.

Mitchell Warren, head of the AIDS advocacy group, AVAC, attended the conference, known as CROI.

“Over the last five years, there is a growing body of evidence that oral pre-exposure prophylaxis, or PrEP, is not just good therapy, but it’s good prevention. With the important caveat¹ that like any effective drug it only works if you take it.”

Warren said three PrEP trials proved the effectiveness of Truvada.

“That is the combination pill of tenofovir plus emtricitabine. Most of the research has been around Truvada. It’s a well established drug. We know it’s a very safe drug. It was widely used in antiretroviral therapy for people infected. So, it was the first of the drugs that have been explored for PrEP. There are other drugs being studied for PrEP,” he said.

One of the trials is called the Partners Demonstration² Project. It’s based on an earlier study in Kenya and Uganda of so-called “discordant” heterosexual couples. That’s where one partner is HIV positive and the other is not.

Warren said, “This was a project that enrolled³ new couples – a very large number of couples – in the two countries. And it was offering treatment to the HIV positive partner. But if the partner didn’t want to be on treatment – or if they were on treatment but not yet virally suppressed, which would give protection to their negative partner, as well – the PrEP was provided to the HIV negative partner as a bridge until the positive partner was virally suppressed.”

The study shows the use of PrEP reduced the risk of HIV infection by 96 percent.

Next, there’s the PROUD Study. It was done in Britain among high risk men who have sex with men, or MSM. All in the study were HIV negative.

“One of the important questions of the Proud Study was: would people change their behavior? You know, one of the big concerns over the last several years was that if everyone kind of ran to PrEP they abandon condoms. They would change their behaviors and be riskier⁴. This was another piece of great news. It showed that there was an 86 percent reduction in risk among those people who were offered and took PrEP,” said Warren.

He said the Proud Study also shows there was a similar reduction in risk from other STIs or sexually transmitted infections.

The third – called IPERGAY -- took place in France and Canada. It enrolled MSM, who reported having frequent sex. It, too, shows an 86 percent reduction in risk.

“But this was a different study,” said warren, “They were trying to see if a different dosing schedule might also be effective. Rather than telling people to take it every day, what the participants in this trial were told was to take two pills within the 24 hour period before you think you might have sex. And if you do have sex, you should then take another pill 24 hours after having sex – and then another pill 24 more hours later. So, it’s basically four pills within three days.”

He said for the findings to have an effect in the real world, there needs to be an action plan that includes resources and research agendas. He says the focus should be on those “most at risk, especially young African women.”

“One of the things about science presented at CROI is that it’s often very elegant science, but it doesn’t have any impact on the epidemic⁵ if you don’t act on the science. The drug Truvada that is used for PrEP right now is only approved for use as prevention in one country, the United States. And there is an urgency -- and frankly⁶ a moral imperative⁷ -- that the drug get registered as a preventive tool in many, many more countries,” he said.

The AVAC leader cautioned PrEP is not for everyone. Efficacy trials continue for effective vaginal gels or rings containing antiretrovirals, as well as injectable ARVs taken every two to three months. Vaccine⁸ trials also continue. 

Also at CROI, Doctors Without Borders released the findings of its HIV studies. The group, also known as MSF, said, “Among individuals not receiving antiretroviral treatment, men had twice the level of HIV virus in their blood as women at the same stage in the disease.” It says a high viral load greatly increases the risk of infection.

MSF said the findings help explain why incidence is so high among women – and that it could be critical to test and treat men even earlier. The studies were done in Kenya, Malawi and South Africa.

1 caveat   

n.警告； 防止误解的说明

参考例句：

• I would offer a caveat for those who want to join me in the dual calling.为防止发生误解，我想对那些想要步我后尘的人提出警告。
• As I have written before,that's quite a caveat.正如我以前所写，那确实是个警告。

2 demonstration   

n.表明，示范，论证，示威

参考例句：

• His new book is a demonstration of his patriotism.他写的新书是他的爱国精神的证明。
• He gave a demonstration of the new technique then and there.他当场表演了这种新的操作方法。

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 riskier   

冒险的，危险的( risky的比较级 )

参考例句：

• Now they are starting to demand higher returns on riskier assets. 而今他们开始在风险更高的资产上要求更高的回报。
• The problem with that: RIM's business is getting riskier every quarter. 不过问题也随之而来：RIM面临的业务风险正逐季增大。

5 epidemic   

n.流行病；盛行；adj.流行性的，流传极广的

参考例句：

• That kind of epidemic disease has long been stamped out.那种传染病早已绝迹。
• The authorities tried to localise the epidemic.当局试图把流行病限制在局部范围。

6 frankly   

adv.坦白地，直率地；坦率地说

参考例句：

• To speak frankly, I don't like the idea at all.老实说，我一点也不赞成这个主意。
• Frankly speaking, I'm not opposed to reform.坦率地说，我不反对改革。

7 imperative   

n.命令，需要；规则；祈使语气；adj.强制的；紧急的

参考例句：

• He always speaks in an imperative tone of voice.他老是用命令的口吻讲话。
• The events of the past few days make it imperative for her to act.过去这几天发生的事迫使她不得不立即行动。

8 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。