Feb. 9, 2005 - Routine, voluntary HIV testing coupled with treatment could bring the U.S. AIDS epidemic to the brink of extinction.
That suggestion comes from respected AIDS researcher Samuel A. Bozzette, MD, PhD in a Feb. 10 New England Journal of Medicine (NEJM) editorial.
Bozzette's bold calculation is based on two independent NEJM studies showing that routine HIV testing would be far more helpful than previously thought. Using different techniques, the studies came up with nearly identical findings. They make a strong case for an aggressive attack on AIDS in the U.S., says Yale researcher A. David Paltiel, PhD, co-leader of one of the studies.
"We wired together all those forms of data that describe what this disease can do to people in order to find out what people can do to this disease," Paltiel tells WebMD. "A third of the people with HIV in this country -- fully 280,000 Americans -- are unidentified. They are not getting care. They are not getting counseling on how to prevent transmission. And we find that we can provide those things affordably and effectively."
Douglas K. Owens, MD, senior investigator at the VA Palo Alto Healthcare System, led the second study.
"We found that HIV screening provides a very substantial benefit, both for the infected person and for the community, because of decreased HIV transmission," Owens tells WebMD. "The benefit is so substantial that it makes economic sense -- more sense than we previously understood -- to screen for HIV in groups where HIV prevalence is low. And we are talking about voluntary screening."
Some 40% of the estimated 950,000 Americans with HIV get sick before they find out they're infected with the AIDS virus. By then, their bodies are crawling with infectious virus and their immune systems are badly damaged.
It's obvious that getting earlier testing and treatment would be a big help for these people. But it would also be a big help for the country at large. People who know they are infected aren't as likely to spread the infection. That's because they tend to get counseling on safer sex and drug-use behavior. It's also because they get treatment with AIDS drugs, which dramatically reduce the amount of infectious virus in the body.
Bozzette's calculation is that routine HIV testing and treatment can greatly slow the spread of AIDS. The effect can be great enough for a single medical advance - say, a vaccine that is only 50% effective - to wipe out AIDS in America.
"For any epidemic to perpetuate itself, each infected person has to infect at least one other. The closer you are to driving that number below 1, the closer you are to extinguishing the epidemic," Bozzette tells WebMD. "So if you can identify people who are transmitting HIV and reduce the probability they are going to transmit, it makes it easier to move to that point. Then let's say we get a partially effective HIV vaccine that cuts transmission by half. Well, if you have already reduced transmission substantially, that may be enough."
Can routine HIV testing really work? The idea is to link testing to routine health care. Anyone seeing a doctor, whether for a checkup or for emergency care, would be offered an HIV test. One-time screening would be enough for populations with very low HIV infection rates. For everyone else, testing every three to five years would be needed.
Note that people would be offered an HIV test. It would be routine, but voluntary. Is there any reason to believe that enough people would agree to be tested?
Yes, says Harvard researcher Rochelle P. Walensky, MD, MPH, co-leader with Paltiel of one of the studies. Working with the Massachusetts Department of Health, Walensky has already set up routine HIV testing programs.
"Early on the acceptance rate was not high," Walensky tells WebMD. "Acceptance was lower than for prenatal HIV testing programs. A mom is more likely to accept testing when her baby is involved. But what we found is that, over time, the acceptance rate increases. So if we had routine, voluntary HIV testing, at first it would be a bit of a culture shock, then it would become normal."
Walensky notes that many people are surprised to find out that their doctor isn't already testing them for HIV - a dangerous misconception that routine, voluntary testing would fix.
Paltiel stresses that just because routine HIV testing is cost-effective doesn't mean it is free.
"It is expensive to test and counsel and treat people for HIV disease," Paltiel says. "It is efficient. But you do not get health for free. It costs to implant defibrillators for heart patients, or to screen for diabetes. And it's the same for HIV. It triggers a whole path of expensive drugs."
The U.S. has a program for ensuring that people with HIV infection have access to the drugs they need. But funding for that program already is stretched to the breaking point. Testing would add to those costs - because it doesn't do any good to find people with HIV if you aren't going to treat them.
"My feeling is momentum for widespread, routine HIV testing is going to build," Bozzette says. "People will begin to recognize that finding AIDS cases is not as cost-efficient as finding recent HIV infections. And by preventing HIV transmission, we have a chance in this country to draw a circle around the AIDS epidemic. We can reduce the probability that future generations will suffer the way this generation has."