A virus is an infective agent that typically consists of a nucleic acid molecule in a protein coat. It is too small to be seen by light microscopy and is able to multiply only within the living cells of a host. One virus that has received global attention over the last thirty years or so is the HIV/AIDS virus. This virus attacks the body’s immune system, which in turn stops the body’s ability to be able to fight off illness. Thus, people who contract HIV/AIDS are susceptible to death by sicknesses that a healthy individual is able to recover from easily.
The cause of acquired immune deficiency syndrome (AIDS) is human immunodeficiency virus type 1 (HIV-1). HIV-1 is not just one virus, but comprises four distinct lineages each with very different frequency and each resulting from an independent cross-species transmission event. The groups are named M, N, O, and P; M is the most widespread form and constitutes about 98% of HIV infection around the globe (Sharpe 2010 2487). Groups N, O, and P are rare, and largely restricted to Cameroon and surrounding countries. The forth and most recent P group strain of HIV-1 is closely related to the gorilla viruses and has most likely resulted from gorilla-to-human transmission (Sharp & Hahn 2489). The HIV virus blocks the functions of tetherin in the human body. Tetheirn is a mammalian host protein with a recently discovered antiviral activity. Tetherin dimers appear to form ‘tethers’ between virus envelopes and the cytoplasmic membrane of the cell, preventing the release of those viruses. HIV-1 has adapted over time in attempts to counteract tetherin, which has yielded different results and caused the formation of M, N, O, and P. Only in the case of HIV-1 group has adaptation been fully successful (Sharp& Hahn 2487).
Using evolutionary comparisons, scientist found the probable source of HIV, which is connected to the adaptation of a different virus- SIV simian immunodeficiency virus. The primary symptom of AIDS in humans is a reduction in the number of T-cells, which then reduces the host’s defenses against secondary infections (Sharp& Hahn 2490). The same results are seen in SIV in chimpanzees and apes. Over many decades of observation, scientists have discovered that the death rate for chimpanzees who are infected with SIV is ten times that of an otherwise healthy chimp. It has also been recorded that fertility rates are significantly reduced in SIV-positive females, both in terms of their birth rate and the survival of their offspring (Sharp& Hahn 2490). The source of HIV-1 group M, the main pandemic AIDS strain affecting humans, has been traced to a virus infecting a specific central subspecies of chimpanzees who live in a remote area in the southwest corner of Cameroon, Africa. The likeliest route of chimpanzee-to-human transmission would have been through exposure to infected blood and body fluids during the butcher of bushmeat. After infection, main waterways served as a way for...