World AIDS Day 2007

On this World AIDS Day, we would like to commend the advances made in our knowledge of HIV/AIDS over the past year. Epidemiologic and clinical trials have confirmed that, at least in Africa, male circumcision can reduce the risk of infection by up to 60%. It remains to be proven what the impact of this intervention will be at the population level. Similar preventive approaches with women have evaluated diaphragm use. No decrease in the risk of infection of the women were noted although these studies were done when most of their male partners were using condoms. Thus, whether women, in situations where the choice of protection rests solely with them, would benefit from diaphragms remains to be determined.
 
Vaccines have always played an important role in preventing the spread of infectious diseases. Early work using an envelope protein in the VaxGen trials showed that this direction did not protect against infection or reduce the viral load of those infected. This year, the Merck HIV adenovirus 5 vaccine, evaluating the role of cell-mediated immune responses, regrettably also failed to show any effect on prevention of infection or the level of viral load after infection. In some cases, particularly in volunteers who had pre-existing antibodies to the adenovirus, a trend towards an enhanced risk of infection was observed. These findings place further emphasis on encouraging more basic research studies to develop an effective AIDS vaccine – one that elicits both anti-HIV neutralizing antibodies and cellular responses. 

HIV/AIDS in the developed world has become a chronic disease which requires long-term therapy with anti-retroviral drugs. New treatments are making the use of these anti-retroviral therapies (ART) much easier since treatment with just one pill is now available as well as strategies that reduce toxicity. Whether this chronic use of ART will lead to an increased prevalence of diseases of aging or neurologic conditions related to HIV infection is a concern. Importantly, in developing nations, therapeutic programs need to become more widespread. We believe that eventually all infected people needing treatment will receive ART through the help of wealthy countries. Testing of all individuals at risk is also essential both in developing ánd industrialized countries since early diagnosis will lead to better control and better prognosis for the infected individual.

Continual basic research studies are needed and should focus on the emergence of recombinant viruses that may be more cytopathic than parental strains, escape immune response and be resistant to ART. Moreover, attention to innate immune responses merits a high priority, particularly the role of NK cells, dendritic cells, and CD8+ lymphocytes. Maintaining this immune system’s activity assures long-term survival from the infection, and inducing this response with vaccines can elicit the most effective adaptive immune responses. We look to 2008 with anticipation of additional results from vaccine trials, better antiretroviral therapies, and further understanding of how the virus and the immune system interact to cause disease. With this knowledge, new approaches can be developed for prevention and treatment of HIV infection.
 
Jay A. Levy, M.D., Editor-in-Chief
Brigitte Autran, M.D., Ph.D.
Roel A. Coutinho, M.D.
John P. Phair, M.D.
Editors of AIDS

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Dr. Jay A. Levy, the Editor-in-Chief of AIDS, is Professor of Medicine, Research Associate in the Cancer Research Institute and the Director of the Laboratory for Tumor and AIDS Virus Research at the University of California in San Francisco (UCSF). His most recent book, HIV and the Pathogenesis of AIDS (third edition) covers all aspects of the HIV/AIDS field and is available from ASM Press.
Dr. Brigitte Autran is a physician-immunologist at the Laboratoire d'Immunologie Cellulaire, Hôpital Pitié-Salpétrière, Paris, France
Dr. Roel Coutinho is a physician-epidemiologist at the University of Amsterdam, Amsterdam, Netherlands 
Dr. John Phair is a physician with an expertise in infectious diseases. He is at Northwestern University, Chicago, Illinois