The cover of a recent issue of Science magazine, the voice of the American Association for the Advancement of Science, heralds as the scientific breakthrough of the year the acceptance of HIV treatment with antiretroviral drugs, ARVDs, as an effective regimen for the prevention of the disease. Promoted by what has been described as a splashy World AIDS Day event attended by three U. S. Presidents, business magnates and rock stars, this conclusion was based on the results of a study of 1,763 couples where only one of the partners tested positive for the HIV virus. All those who tested positive included in the study were characterized as having intact immune systems. The study design was to give half of the group of infected individuals ARVDs and withhold this treatment from the other half until their immune system was seriously compromised. The results of the study demonstrated a significant lowering of the rate at which the HIV free partner in the couple became infected and at the same time improved the health status of the infected partner as demonstrated by blood tests. One of the lead investigators, Myron Cohen of the University of North Carolina Medical Center, characterized the findings as unambiguous.
This human experiment is applauded while at the same time we have to deal with details of an experiment in the 1940's involving more than 1,300 Guatemalans who were intentionally exposed to sexually transmitted disease. A recent Presidential Commission report has made 14 recommendations to increase the protection of those who volunteer for federally funded research. This is not a trivial task in view of the more than 18 federal agencies conducting or funding more than 55,000 thousand studies involving human subjects.
An unmentioned caveat and potentially significant issue is the finding reported in the same issue of Science magazine that even when antiviral drugs reduce HIV to undetectable blood levels, active live virus can be demonstrated in tissue. This finding highlights the difficulty in eliminating the virus from the body. A prominent HIV/AIDS scientist has concluded that it is risky to rely on blood levels to reach a conclusion about the effects of therapy.
Another problem with the study findings is highlighted by the current experience with the ARVs which are currently being administered to more than 6 million patients, at a time when almost 3 million are estimated to be newly infected world wide each year. This number is very inexact since, using current testing methods, very early infections are frequently not ascertained at a time when an individual is potentially a far more contagious disease vector. This early, heightened communicability of virus with rapid transmission accelerates the propagation of the epidemic. The issue of continued consistent drug use is another factor in the effective use of ARVs. Problems of developing drug resistance and drug toxicity complicate this already complex problem. The multifactorial nature of the HIV/AIDS epidemic makes it very difficult to extrapolate the results of a relatively small clinical trial to what might be experienced in a population wide prevention/treatment program.
HIV/AIDS was first reported in 1981. At that time, the projected increase in the incidence and prevalence of disease proved to be widely off the mark. The estimated size of the epidemic in the United States for many years was much larger than was actually experienced. The risk factors for the disease, identified over time, were sequentially being a homosexual male, IV drug user or prostitute -- although at the time, we had no idea of the source of this infection that in thirty years is estimated to have infected more than 60 million people worldwide. A variety of theories have been proposed concerning exactly how of this pandemic began. While it is widely accepted that the epidemic originated in Africa, it is also thought that the combination of urbanization, prostitution, increasing global travel, the treatment of sexually transmitted diseases and the use of medical injections provided the conditions for the spread of the disease around the world.
Regardless of its origins, forty years after the beginning of the epidemic, we still do not have an effective strategy for preventing the further spread of the disease or a regimen that does any better than make it a chronic condition with a natural history that often includes many significant complications that are enormously expensive to manage and frequently lead to disability and death.