Thirty years ago, the first five cases of what is now known as the acquired immune deficiency syndrome were reported in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report. The amount of knowledge gained since then has been extraordinary, and the pace at which research findings have been translated into lifesaving treatments and tools of prevention is unprecedented, although much remains to be done with regard to delivering the fruits of this research to the people who need them most.
The discovery of the human immunodeficiency virus as the cause of AIDS in 1983-84 was followed by an understanding of how HIV leads to AIDS; the natural history and epidemiology of the disease; the creation of a diagnostic blood test; and the development over the years of more than 30 antiretroviral drugs.
The approval of the first protease inhibitors in 1995-1996 paved the way for powerful, multi-drug antiretroviral therapy. The many combination regimens now available using different classes of antiretroviral drugs have dramatically improved the quality of life and extended the life expectancy of people with HIV. An HIV-infected person properly treated with this combination therapy, and provided other needed care and services, now can expect to live for decades after being diagnosed.
Antiretroviral treatment regimens also can prevent HIV infection. When given to pregnant HIV-infected women and their newborns, these drugs have been enormously successful in preventing mother-to-child transmission of HIV. Moreover, just three weeks ago, a rigorous, controlled clinical trial conducted in nine countries confirmed another potent way to apply treatment as prevention. The study results were striking: Among more than 1,700 heterosexual couples in which one partner was HIV-infected and the other was not, starting combination antiretroviral therapy immediately in the infected partner when blood tests indicate his or her immune system is still strong resulted in a 96 percent reduction in HIV transmission to the uninfected partner, compared with deferring treatment until the same tests showed the immune system to be weaker.
This recent report confirms that combination therapy not only benefits the infected individual but also can reduce the risk of transmitting the virus to others. By confirming that this type of therapy can do double duty as treatment and prevention, this study has energized the medical, public health and activist communities. In addition to its role in protecting babies from infection, “treatment as prevention” to block sexual transmission now can be added to our toolkit of proven HIV prevention interventions, which also includes behavioral modification, condom distribution, the provision of clean needles and syringes to injection drug users, medically supervised adult male circumcision, and other approaches.
Meanwhile, other recent progress in HIV research gives us hope that we soon will have additional prevention tools. Notably, a once-a-day pill combining two antiretroviral drugs was shown to reduce the risk of HIV acquisition in men who have sex with men, and an antiretroviral-based, vaginally-applied gel did the same for heterosexual women.
Although a protective HIV vaccine remains elusive, we are encouraged by the recent demonstration that a vaccine tested in Thailand provided modest protection against HIV. Researchers now are examining blood samples and data from the Thai trial to determine how the vaccine prevented HIV infections, information that will help guide efforts to improve on those results.
Scientists also are pursuing many other research avenues, including structure-based vaccine design. With this approach, researchers characterize in exquisite detail key molecules on the HIV virus and use these structures to design new components for next-generation HIV vaccine candidates.
Entering the fourth decade of HIV/AIDS, our task is to build on these advances and deliver scientifically validated interventions to everyone who needs them, in the United States and abroad. Six in ten HIV-infected people in developing countries who need combination antiretroviral therapy are not receiving it, which puts their health and that of their sexual partners at risk.
Domestically, access to treatment and care also is not optimal. A recent analysis estimated that of the 1.1 million people living with HIV in the United States, approximately 20 percent are unaware of their infection. And within the entire group of infected people, only about 19 percent have a viral load that has been driven to undetectable levels by combination therapy. Both at home and globally, greater numbers of HIV-infected individuals need to be identified early in the course of their disease through expanded voluntary HIV testing programs and linkage to appropriate care and antiretroviral treatment.
In addition, prevention programs using proven tools must be dramatically “scaled up,” refined, improved and made more cost-effective. At the same time, we must continue to develop additional effective prevention strategies.
We also must find innovative approaches to curing HIV/AIDS by eradicating or permanently suppressing the virus in infected people, thereby eliminating the need for lifelong antiretroviral therapy. In this regard, important new research is being undertaken by the National Institutes of Health and other organizations. In addition, a robust research effort is critical to address the malignancies, cardiovascular and metabolic complications, and premature aging associated with long-term HIV disease and/or antiretroviral therapy.
Despite these challenges and the huge burden of this modern-day plague, we now look at the fight against HIV/AIDS and our chances of prevailing with considerably more optimism than we previously have felt. With the medical and public health tools now or soon-to-be available, controlling and ending the global HIV/AIDS pandemic are feasible goals.
Unfortunately, we are in a difficult situation of considerable global constraints on resources to support this goal. Every effort must be made to efficiently apply existing resources so that proven interventions are delivered in the most cost-effective manner. In addition, public-sector, commercial and philanthropic commitments to HIV/AIDS research and implementation of proven findings must be sustained and strengthened with the investment of additional resources to ensure that HIV treatment and prevention services are universally available to the people who need them, wherever they live.
With a global commitment, we can control and ultimately end the HIV/AIDS pandemic. On this commemoration of the 30-year anniversary, let us recommit ourselves to that goal.