Thirty years ago, in the summer of 1981, the first cases of what became known as AIDS were recognized in the United States. Within a relatively brief period of time it became clear that we were dealing with a runaway pandemic that was global in nature. We had no idea how bad it would get, but the idea of ending the pandemic was not even a consideration.

Since then, some 65 million people have been infected with the human immunodeficiency virus (HIV) and more than 30 million have died. Today, 34 million people are living with HIV and 2.7 million people were newly infected in 2010 alone. Yet, much progress has been made, none more impressive than in the treatment of HIV infection. About 30 powerful anti-HIV medications -- antiretrovirals -- are now available; these drugs given in combination can provide HIV-infected people with a near-normal life span. Global programs such as the U.S. President's Emergency Plan for AIDS Relief (PEPFAR) and the Global Fund to Fight AIDS, Tuberculosis and Malaria, as well as philanthropic organizations such as the Bill and Melinda Gates Foundation, the William J. Clinton Foundation and others have been established. They have provided life-saving antiretrovirals to millions of HIV-infected people in low- and middle-income countries at a scale unimaginable a few years ago (about 6.6 million by the end of last year).

Without question, the treatment of HIV infection is a critical tool in our response to this devastating pandemic. However, the large number of people who become infected each year, referred to as the incidence of infection, drives and sustains the pandemic. In this regard, prevention of HIV infection is critical. Prevention methods such as proper and consistent use of condoms, behavioral modification, prevention of mother-to-child transmission of HIV and needle and syringe exchange programs for injection drug users have significantly decreased new infections. However, they alone have not reduced incidence enough to dramatically change the trajectory of this terrible pandemic.

Fortunately, this situation recently has begun to change. Newer, additional prevention approaches are now available, such as medically supervised adult male circumcision, which has resulted in dramatic and durable reductions of more than 60 percent in HIV acquisition among heterosexual men. Topical vaginal gels containing anti-retroviral drugs have shown some promise as a female-controlled method of preventing infection; however, these results need to be confirmed. And the use of antiretrovirals in HIV-negative people may prevent infection under certain circumstances. Thus, we now have a robust combination prevention "toolkit" that can be tailored to the specific circumstances of the individuals at risk for HIV infection in a given population.

Both the prevention of HIV infection and the life-saving effects of antiretroviral treatment are critically important, but unfortunately there has been a tension between the allocation of resources for HIV prevention vs. those for treatment in strategies to end the pandemic. Recent scientific data showing that treatment, besides saving lives, can actually be considered as an important new component of the combination prevention toolkit, has removed this artificial tension. This transforming concept was solidified this year by a carefully-controlled clinical trial showing that when HIV-infected people are treated adequately with antiretroviral drugs, the likelihood that they will transmit infection to their heterosexual partners decreases dramatically. Thus, treatment has the potential double benefit of saving the life of the infected individual at the same time as preventing that person from transmitting infection to his or her sexual partner. Treatment is prevention, and the more people you treat, the more infections you will prevent.

Mathematical modeling of scaling up the proven non-treatment related prevention methods such as condom use and adult male circumcision at the same time as scaling up treatment of infected individuals (and thus preventing even more infections) indicates that a tipping point could be achieved and the trajectory of the pandemic dramatically altered. Thus, the goal of ending the HIV/AIDS pandemic is achievable.

Rather than frantically chasing a runaway pandemic, we now have the medical and public health interventions at our disposal to control and ultimately end the HIV/AIDS pandemic. It is a moral and public health imperative that we strive as a global community to deliver these services to all who need them, in rich and poor countries alike. Together, we have the opportunity to participate in an historic global health victory: the end of the HIV/AIDS pandemic.

Dr. Fauci is Director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, and Chief of the NIAID Laboratory of Immunoregulation.