Science is still in the dark on how to combat AIDS

    Last year some 33 million people died of AIDS, including 75,000 in Latin America. Every day somewhere in the world 6,800 people contract the disease. Yet "the most promising vaccine prospects have failed" to stop the advance of the disease, according the a report in Scientific American (11-2008). In Latin America it is estimated that two million people have AIDS and the United Nations puts infected persons in Argentina at 120,000.

   Infection can only occur during sexual relations, including oral sex if there are any open lesions in the mouth, according to experts. However, it has been proven that there is absolutely no possibility of contracting the disease as a result of hugging, kissing, sharing glasses or other kitchen utensils, used clothing or shoes, sheets, at swimming pools, due to contact with sweat or tears; likewise, insects cannot transmit the disease. Therefore, discriminatory practices against AIDS victims have no substance.The most effective way to prevent contagion is the use of preservatives, safe sex or abstention.

    "Twenty-five years after isolating HIV, we still have no effective vaccine," says David I. Watkins in a Sientific American article entitled "The Vaccine Search Goes On." He laments that "we in the field have realized that if none of the classical methods of making vaccines works against this virus, then we need a new one--some unusual creative approach that has yet to be imagined or some new insight into the virus itself that might reveal a vulerability."

    That is, researchers have to  go back to the basics. The problem is that to devise vaccines and new treatments for HIV it you need solid knowledge of the virus´s life cycle. It invades host cells and then commands their machinery to make more copies of itself. Watkins explains: "First, a protein called Envelope on the virus must bind to CD4 and CCR5 proteins on the cell surface. As the virus fuses with the cell, it empties its contents into the cytoplasm. A viral enzyme, reverse transcriptase, then copies the virus´s RNA genome into double-stranded DNA, often making errors that generate diversity in the virus copies. Another viral enzyme, integrase, inserts the copy into the host DNA. Cell machinery transcribes the viral genes back into RNA (including RNA that can serve as templates for proteins) that travels to the cytoplasm, where ribosomes produce the encoded proteins. Viral RNA and proteins then move toward the cell membrane, where they gather into a budding virus particle. In the immature new virus copy, the HIV protease enzyme modifies viral protein chains, enabling the particles, or ´virions,´to mature into a form that is ready to infect a new cell."

   So, scientists are wracking their brains while the disease easily escapes attempts to harass it. Few experts expect to see an effective vaccine in less than a decade and even then there may be no clear solution to the problem. That would appear to be a powerful argument to employ protection, in spite of the frequently voiced objection of conservatives and certain religious groups to the use of preservatives.