“It’s a mixed picture,” says Tom Quinn, director of the Johns Hopkins Center for Global Health, as he surveys the HIV/AIDS battles won and lost in 2007. With an estimated 33 million people infected worldwide, the global AIDS epidemic continues to gather momentum. In a recent interview, Quinn, MD, offers some surprising insights into the epidemic, as well as some sobering news. “How we’re doing depends on your perspective.” Christine Grillo, a writer with the Office of Communications and Public Affairs (OCPA), spoke with Dr. Quinn about global progress against the disease. OCPA: We’re more than two decades into the HIV/AIDS epidemic now. How are we doing in terms of treatment?
TQ: It’s been 26 years since the original recognition of AIDS, and probably much longer in terms of circulation of the virus. How we’re doing depends on the perspective. From the perspective of treatment, we’re making great advances. We’ve made this a chronic disease for people living in the developed world. The rollout of antiretroviral (ARV) therapy in the developing world is proceeding as expected—it could be faster, but we really have increased the number of people in treatment substantially over the last three years. So in that sense we’re making great strides. OCPA: And how about from the perspective of prevention?
TQ: The cases are continuing to escalate worldwide, with three million deaths a year and over 3 million new infections a year—from that perspective we’re losing the battle. We have made some great advances in prevention, such as circumcision. Another huge advance has been in prevention of mother-to-child transmission. We should be able to prevent mother-to-child transmission 100 percent of the time, but it has been hard to scale it up in developing countries because there’s a lack of infrastructure, a lack of funding and a lack of support for programs. So it’s a mixed picture. We have our successes, we have our failures. The ultimate perspective at this point is that we’re still losing the battle. OCPA: Recently, the UN cut its HIV/AIDS estimate from 39 million infected to 33 million infected. Is this good news?
TQ: It’s neither good nor bad news. Estimating how many people are living with HIV infection is an inexact science; the downward estimate does not reflect a decrease, but rather an improvement over previous years of estimates. Whether it is 33 million or 39 million, it is still too many infected people. OCPA: You mentioned circumcision as one of our successes. How successful is it?
TQ: In 2007, the big success is undoubtedly circumcision. Nothing can come close to it, and if we had a vaccine that can do what circumcision does, we’d be dancing in the streets. The problem is that circumcision is surgery—it requires infrastructure, scale-up and access in areas that don’t practice it routinely. [Editor’s note: The Data Safety Monitoring Board (DSMB) stopped all three circumcision trials in Kenya, South Africa and Uganda because of proven effectiveness. The trials showed a 50 to 75 percent reduced risk of infection, and over time the efficacy further improves. The World Heath Organization and UNAIDS now endorse it.] OCPA: Any other successes over the years?
TQ: There have been four major successes in the battle against AIDS. The first was screening the blood supply around the world. The second was antiretroviral therapy to prolong survival. The third was using antiretroviral therapy to block mother-to-child transmission. And I would say the fourth is circumcision. I haven’t included behavioral interventions among those four. Some of these programs have worked, but are they ranked up as high as these other four? I don’t think so. These four have changed the face of AIDS on this earth. OCPA: Ugandan President Museveni is reluctant to endorse circumcision. Have other leaders resisted? Any thoughts about how to proceed?
TQ: President Museveni has not endorsed circumcision as a major intervention for his country, but it’s not because of cultural barriers. He truly believes that circumcision detracts from his primary campaign of ABC [Abstinence, Be faithful, Condoms]. He’s concerned that men will get circumcised and then think that they are protected and engage in high-risk behavior. But Botswana has signed on, Kenya has signed on. Swaziland and the South African leaders have signed on. You really do need political support for these things to scale up. OCPA: Speaking of ABC, the “A” provision has come under quite a bit of fire. What’s your opinion of PEPFAR’s funding for abstinence education?
TQ: I think abstinence education should be encouraged in children before they begin engaging in sex. But once individuals have started sexual activity or are in a long-term relationship or are married, abstinence is no longer an option, or it’s less of an option. I actually think the most effective control programs would be those that provide funding for the whole package, A, B and C education, and I think that education programs should be decided by the cultural context and not by the fixed proscription of percentages. OCPA: In a recent lecture you mentioned that men control the spread of HIV/AIDS. Would you elaborate?
TQ: Men are the primary vectors of HIV. We know that from the truck drivers, where they would go and get infected in one town and disseminate it along the truck route and so forth; that’s been well studied. Part of it is that it’s a cultural phenomenon in many places that women are less empowered in sexual relationships, and it’s often very difficult for a woman to tell her partner to wear a condom. It’s stigmatizing for her to try and promote condoms for her partners, even in commercial sex work. While I say that men are the main vectors, it’s more an issue of empowerment: women are less empowered in sexual relationships to enact the appropriate interventions. OCPA: You said in an earlier lecture that antiretroviral therapy potentially can reduce the viral load in HIV-positive individuals and thereby reduce transmission. Is scaling up ARV therapy the solution to both treatment and prevention?
TQ: ARV therapy alone won’t be a solution to the HIV pandemic. For every person we get on the therapy, six new people get infected. Nearly half of all transmissions occur in the first year that a person gets infected, probably the first few months, when they have acute HIV. But most of them don’t even know they’re infected. And now that the virus is a treatable disease, it’s less frightening. We’re actually seeing a rise in syphilis, Chlamydia, gonorrhea, even in this country—it’s clear that high-risk activity is escalating once again, across the populations. Will ARV therapy reduce transmission? Yes. Will it reduce it enough? No. We must build both treatment and prevention programs that include counseling, testing, behavioral modifications and interventions such as needle exchange programs, being faithful and condoms. If you’re successful in both programs, you will be able to achieve a reduction in the spread. OCPA: Any words of caution about ARV therapy? You’ve mentioned the looming possibility of drug resistance.
TQ: Resistance does occur, but it’s much lower than anyone expected, because a lot of work’s gone into improving adherence. We’re seeing much lower rates of resistance in places like Africa than in the U.S. or in Europe. It wasn’t until 1996 that we really learned that we’ve got to use three drugs and they have to be used in a very adherent program. The problem is, in America, you had all those HIV-infected people going from monotherapy to dual therapy and then to triple therapy, and many were non-adherent to their drug regimens. This led to the development of resistance—so we now have a big percentage of our population that’s resistant. In Africa, we at least started with triple therapy and encouraged high adherence, which has kept resistance low. OCPA: Are there any good ideas out there about how to increase adherence to ARV therapy? Any implants or patches in the pipeline?
TQ: There’s not much to say about that. Antiretroviral therapy can’t be administered via patch or injection because their levels might drop below a critical point, which would allow resistance to develop. I’ve yet to see an implantable device with an HIV-killing drug. OCPA: In a recent talk at the Bloomberg School, you sounded pessimistic about HIV vaccine development. Are there any good candidate vaccines on the horizon?
TQ: I am pessimistic as a result of the recent vaccine trial using a Merck vaccine with an adenovirus vector that showed that the vaccine inadvertently enhanced susceptibility to HIV infection. This was a disaster of monumental proportions and a huge setback to the vaccine field because many of the subsequent vaccines in the pipeline are based on that same theory, and unless they’re altered a certain way, we’ve probably lost 5 years—and that’s very depressing. OCPA: There’s been criticism of the science that went into developing an HIV vaccine, with some going so far as to accuse the developers of arrogantly narrowing the focus to exclude other avenues of research. Any comments?
TQ: I would just say that the scientific vigor with which they pursued immunologic aspects of HIV may have unknowingly altered the course of some vaccine candidates. Basically, some investigators found some great discoveries on what we call cytotoxic T-cells and felt this was the way to build a great vaccine. Unfortunately, it left behind a more balanced approach. We need to go back to the drawing board, look at a more balanced approach, learn from our mistakes. That’s the most important lesson here: We need to know why this vaccine trial failed so that we never go down that path again. OCPA: What’s your prediction for the HIV/AIDS epidemic in the next five years?
TQ: New infections will continue to occur in many areas of the world with a continued escalation of incident cases in Eastern Europe, southern Africa and Southeast Asia. I believe that the epidemic will stabilize in many areas like the U.S., Latin America and Western Europe, but it will continue to dominate the health care sector with increasing need for treatment for those advancing to clinical AIDS. We cannot treat ourselves out of this epidemic—we need to markedly increase our prevention efforts for uninfected individuals, as well as to promote prevention for infected individuals who might transmit it to others. If we do not fully endorse every prevention modality and integrate them with treatment and care, this epidemic will only get worse. —Christine Grillo
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