AIDS Research Holds Promise for Reducing HIV Transmission Rates
'Extraordinary advances' prompt some to dare to dream of a cure
THURSDAY, Dec. 1, 2011 (HealthDay News) -- The data may at first seem dire: More people are living with HIV/AIDS than ever before in the United States, according to the U.S. Centers for Disease Control and Prevention.
But researchers say that's actually good news because people are living with the disease through effective medical treatment, rather than dying from its relentless progress.
But even better news comes in the form of potential new treatments that could keep people from acquiring HIV in the first place -- progress that will be noted Dec. 1 as countries around the world mark World AIDS Day.
"AIDS research has brought us some extraordinary advances over the past couple of years," said Kevin Robert Frost, chief executive of amfAR, the Foundation for AIDS Research. "When you take all that and combine it with the other preventive measures we know of, we have this phenomenal toolbox at our disposal for radically reducing transmission."
These advances include new ways to prevent transmission, as well as growing evidence that early and effective treatment of HIV in those already infected actually prevents the virus from spreading to others.
Some researchers are even beginning to become excited about the prospects of finding the holy grail of AIDS research -- an actual cure for the dread disease.
"Every day . . . I hear growing enthusiasm [that] we can cure this disease," Frost said. "We think it's possible. We think we could get there."
According to the CDC's most recent tally, more than 1 million adults and children in the United States were living with HIV in 2008. That's an increase of about 7 percent from the agency's previous estimate, made in 2006. Experts at the CDC say the increase is a good sign that disease management is working, but they also point out that more people are becoming infected with HIV than are dying from HIV or AIDS.
Another sign of progress involves the transmission rate of HIV. The CDC estimates that for every 100 people living with HIV, just five end up transmitting the disease to someone else. That's an 89 percent decline in the estimated rate of HIV transmission since the epidemic's peak in the mid-1980s.
The new research that promises to reduce HIV transmission even further includes:
- Evidence that effective treatment prevents transmission. In a government study, called HPTN 052, "it became very clear that people who received early treatment [with antiretroviral medications] had a 96 percent decline in the likelihood they would infect their uninfected partners," said Dr. Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases.
- Development of medication that prevents acquisition of HIV. Another series of studies focused on the use of medications to make a person less likely to acquire HIV, known as PrEP, or pre-exposure prophylaxis. The studies found that non-infected gay or bisexual men who take antiretroviral medications daily are much less likely to become infected. "Basically, it's a pill that could prevent HIV acquisition in gay men if taken once a day," said Frost, noting that one combination drug therapy called Truvada appears to cut HIV transmission by 44 percent.
- Topical prevention for women. Experts say that a woman's chances of acquiring HIV can be reduced through the use of a topical microbicide. One study at Columbia University identified a gel containing a small amount of tenofovir, an antiretroviral medication, that reduced women's risk for HIV infection by 39 percent and risk for genital herpes by 51 percent.
- Male circumcision. Research also has found that circumcised males are as much as 60 percent less likely to acquire HIV, Fauci said. This has led world health leaders to consider promoting circumcision as prevention, particularly in third-world countries.
- Vaccine research. A long-standing quest of AIDS researchers, the development of a potential HIV vaccine, has continued, Fauci said. The largest-ever HIV vaccine trial, conducted in Thailand, reported in 2009 that people who received the vaccine were 31 percent less likely to acquire the virus. "It certainly is not ready for prime time, but it is evidence that we can protect through vaccination," Fauci said.
All of this progress has led researchers to dare to dream of what was once unthinkable -- discovering an actual cure for HIV/AIDS.
"New interest is growing around the concept of trying to cure HIV and AIDS," Fauci said. "Ultimately, get these patients off therapy so they can lead normal lives again."
However, he cautioned that talk of a cure should not be taken as a sign that doctors are near the goal. "This is an aspirational hope," he said. "We don't yet have exciting results."
Frost is concerned that the pace of these advances could flag in coming years as medical research reels from the impact of the global recession.
"The challenge is, it's all happening against the backdrop of the worst financial crisis since the Great Depression," Frost said. "We really need people to support these efforts if we're going to make a difference. Unfortunately, we're victims of our own success. As AIDS becomes more and more a chronic but manageable disease, a lot of the urgency is lost."
The U.S. National Institute of Allergy and Infectious Diseases has more about HIV/AIDS.
A companion article offers more on the emotional toll of living with HIV/AIDS.