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There's news today about a new and highly effective way to stop the sexual transmission of HIV. More than 30 million people around the world currently have the AIDS virus. And now, an international study shows that when people who have HIV take antiviral drugs in the early stages of their infection, it can drastically lower the chances their sex partner will get HIV.
But NPR's Richard Knox says the findings pose a big challenge at a time when private and public funding for HIV treatment is stagnating.
RICHARD KNOX: The new study is the latest in a series of important findings on HIV. A couple of years ago, male circumcision was found to slow the spread of the virus. Then, another study showed that women who applied a gel containing an HIV drug before having sex reduced their chances of getting infected by almost half.
Last fall, researchers showed gay men taking an anti-HIV drug before they got infected lowered their risk of getting the virus.
And today, Dr. Anthony Fauci, the government's top AIDS scientist, unveiled possibly the biggest news so far.
Dr. ANTHONY FAUCI (Director, National Institute of Allergy and Infectious Diseases): The findings of this study strongly indicate that treating an HIV-infected individual sooner rather than later can have a major impact on reducing the risk of HIV transmission to his or her sexual partner.
KNOX: In fact, the virus was almost totally stopped in its tracks. The study signed up nearly 1,800 couples in Africa, South America, Asia and United States. One member of each couple had HIV. The other didn't. Almost all were heterosexual. Half the couples started taking antiviral drugs right away. The others waited until the infected partner showed signs of severe damage to the immune system.
Not only did getting drugs early prevent infection almost entirely, but there were far fewer cases of serious tuberculosis among those who got early treatment. So treatment benefited both the infected person and the uninfected partner.
Dr. WAFAA EL-SADR (Columbia University): The findings from the study are truly game changers. I think the field of prevention has just been rejuvenated again.
KNOX: That's Dr. Wafaa El-Sadr of Columbia University.
Dr. EL-SADR: This data add tremendous urgency to our efforts to try to find people who are HIV infected right in our midst, in our communities, who are unaware of their HIV status.
KNOX: There are at least 200,000 Americans who don't know they're infected with HIV and can transmit it to others. The new study suggests if they could be found and persuaded to take an antiviral pill once or twice a day, the spread of HIV could be slowed down a lot.
Around the world, 30 million people are infected with HIV. Only 5 million are getting treatment.
Dr. Ken Mayer of Brown University says the new study has just added millions more to the list of who should be getting treated.
Dr. KEN MAYER (Brown University): The challenging news is that this creates an increased number of people who would benefit from treatment, so the gap between the number of people on treatment and the number of people who would benefit from treatment actually increases by these findings.
KNOX: But efforts to expand treatment have stalled. So in a sense, today's news pits those who need treatment because they're ill with HIV against those who should get it to prevent new infections. But even if the drug were freely available, it's not easy to get people to take it.
Dr. MAYER: The pill does not remove HIV, and it's not a one-time procedure. So when we talk about earlier therapy, we're talking about people making a commitment to taking medications on a regular basis for essentially the rest of their lives.
KNOX: The World Health Organization says it will put out new recommendations this summer on how to strike the balance between prevention and treatment.
Richard Knox, NPR News.