Anthology: Deciphering AIDS Vaccines
After 25 years of battling the AIDS pandemic that has already claimed the lives of more than 25 million people, the need for an AIDS vaccine has never been greater. Last year marked the culmination of the most ambitious global program to date aimed at providing antiretrovirals (ARVs) to people with AIDS in developing countries. Although the World Health Organization’s ‘3 by 5’ program fell short of its target to place 3 million HIV-infected people on these life-saving medications by the end of 2005, the funding from this program and others—including the Global Fund to Fight AIDS, Tuberculosis and Malaria and the President’s Emergency Plan for AIDS Relief (PEPFAR)—have helped provide ARVs to 20% of individuals in need in low- and middle-income countries.
This is a significant accomplishment and the momentum it has created is helping to bring hope to many communities devastated by HIV/AIDS. Importantly, these programs are also encouraging more and more people to be tested for HIV infection. But the pandemic shows little sign of abating. There are now about 40 million people infected with HIV around the globe, and 4 million of them were infected just last year. The soaring costs of treatment may soon make it unfeasible, perhaps impossible, to provide treatment to all in need.
New technologies to prevent HIV transmission remain an imperative and an AIDS vaccine offers the greatest hope of all for reversing the pandemic. There are still many scientific obstacles to the development of an effective vaccine, but important advancements have been made. Researchers now have a clearer understanding of the earliest immunologic events in HIV infection and are actively studying long-term nonprogressors to understand the mechanisms that allow some individuals to effectively control their HIV infection without ARVs. They are also gathering new insights on how to manipulate animal models to enhance the pre-clinical evaluation of vaccine candidates. These advancements, as well as the results from around 30 ongoing clinical trials of preventive AIDS vaccine candidates in more than a dozen countries around the world, will provide researchers with important clues on how to reach the ultimate goal—an effective AIDS vaccine.