Fight Against AIDS - Help From a Missing Link

More ground has been gained in the fight to combat AIDS/HIV. Researchers involved in a study on chimpanzees that has spanned nine years feel they may have found what some call the “missing link” in HIV as it has evolved through the years. This link helps form a relation between the virus that infects but does not kill many monkeys in the wild and the virus that has killed millions of people worldwide. In their almost decade-long study, the link that was found is contained in the virus that has been causing the chimpanzee population to dwindle at a rapid rate.

Aside from man, chimpanzees are the only other primate that actually get sick and die because of the virus that is similar to the human-equivalent, HIV. As chimpanzees have already been placed on the endangered list, this new trend is troubling. On the flip side, by researching this virus, scientists and physicians might be able to produce more efficient treatments or a vaccine to help protect humans. The primate version of HIV is SIV, otherwise known as simian immunodeficiency virus; however, most primates that contract SIV never get ill from it or show any symptoms. The lead author of this new study, Beatrice Hahn, a medical professor at the University of Alabama in Birmingham, states that “if we could figure out why the monkeys don’t get sick, perhaps we could apply that to people.”

Over the course of the study, researchers studied chimpanzees located in Tanzania at the Gombe National Park. Those chimpanzees that had contracted SIV were up to 16 times more likely to die than those chimpanzees that were SIV-free. Research from necropsies of those chimpanzees that had been infected revealed that, much like humans living with AIDS, their T-cell counts were extremely low. This strain of SIV, researchers noted, was as close a strain to the human version of the virus that they had found. Dr. Daniel Douek, an AIDS researcher at the National Institute of Allergy and Infectious Diseases, states, “From an evolutionary and epidemiological point of view, these data can be regarded as a ‘missing link’ in the history of the HIV pandemic.”

Douek went on to hypothesize that the cell receptors on certain primates like apes and monkeys have perhaps undergone some type of evolution which allows them to survive despite contracting the virus. Unfortunately, chimpanzees’ cell receptors seem to not have evolved in the same manner which accounts to their succumbing to the disease. One big reason for this is that chimpanzees have only recently started becoming infected which could explain why they have not yet adapted. Hahn believes that humans and chimpanzees first contracted the virus by digesting monkey meat that was infected. In addition, both chimpanzees and humans spread the virus through sexual encounters.

Michael Wilson, an anthropology professor from the University of Minnesota, and a co-author on the study notes that the African chimpanzee population is decreasing due to many factors, including disease, hunting and a loss of space. Because of this, it is difficult to determine how large a part SIV is contributing to that decrease in population. Wilson states, “It is a concern. The last thing these chimps need is another source of mortality.”