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The Acquired Immunodeficiency Syndrome

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The Acquired Immunodeficiency Syndrome

The acquired immunodeficiency syndrome (AIDS) was initially recognized in the first half of the twentieth century and has since become a major worldwide epidemic (“Discovery Health”). Debate about the origin of AIDS has enticed considerable concern and controversy since the advent of the epidemic. It is has been proven that AIDS is caused by the human immunodeficiency virus (HIV) by stimulating the destruction and functional impairment of cells in the immune system, potentially destroying the human body’s ability to fight infection (“CDC”). While there is no cure for the AIDS epidemic, a combination of historical studies and expanding medical technology enable it to be controlled in the course of the future. Knowing where the disease came from and the development of HIV is essential in creating a vaccine and more efficient treatment against the virus.

Evidence that the AIDS disease is caused by the HIV virus include numerous international studies indicating that virtually all patients diagnosed with AIDS are HIV seropositive; they carry antibodies that depict HIV - infection. Also, modern techniques have allowed the isolation of HIV in all AIDS patients, as well as in nearly all HIV seropositive individuals with both early and late stage disease. Furthermore, a 1999 case reported to the Center of Disease Control and Prevention (CDC) accounted three laboratory employees as infected with AIDS after accidental exposure of concentrated replicas of HIV in the laboratory; in all three instances, HIV was insulated and attest to be the infecting cause of disease (“CDC”). Such examples, demonstrating HIV as the cause of AIDS, satisfy nineteenth century physician’s, Robert Koch’s, accredited postulates of disease stating that: “one, the suspected cause [HIV] must be strongly associated with the disease [AIDS]; two, the suspected agent can be isolated and propagated outside the host, and three, the transfer of the agent to an uninfected host, man, or animal, produces the disease in that host” (“Koch’s Postulate”). Thus, to find the genesis of AIDS, scientists must find the source of the HIV virus.

HIV is subdivision of a group of viruses classified as lentiviruses. Lentiviruses excluding HIV have been discovered in a broad range of nonhuman primates, scientifically referred to as simian immunodeficiency viruses (SIV); it has been universally accepted that HIV is a descendant of SIV since certain simian immunodeficiency viruses share a mutual resemblance to HIV - 1 and HIV - 2, the two types of HIV.* (“Avert”). For example, in February 1999, it was declared that a group of researchers from the University of Alabama had studied frozen tissue from a chimpanzee and found that the simian virus it carried (SIVcpz)* was almost identical to HIV - 1. The researchers contended that such evidence indicates that chimpanzees were the source of HIV - 1, and that the virus, at some point, intersected between human and simian species (Edell). However, it is not necessarily certain that chimpanzees are specifically the original cause for HIV - 1 because chimpanzees are seldom infected with the SIV virus. It has been ascertained that viruses can pass from animals to humans by the process of zoonosis (“CDC”). It has been suggested that HIV could have extended from chimpanzees as a result of human consumption.

During recent years it has become possible to determine the particular subtype of the virus. Analyzing the subtype of virus of some of the earliest known cases of HIV infection can provide indication about the time of origin and succeeding development of HIV in humans. Three of the earliest instances of HIV infection include a plasma sample taken in 1959 from an adult male subsiding in what is now Democratic Republic of Congo, tissue specimens from an African - American teenager who died in St. Louis in 1969 and a Norwegian sailor who died in 1976 (“Avert”). Studies of the plasma sample from 1959 indicate that HIV - 1 was introduced into the human race around the late 1940's. On the contrary, other scientists have interpreted that the epidemic could have begun over one hundred years ago. Furthermore, in January 2000, the results of a recent study presented at the Seventh Conference on Retro Viruses and Opportunistic Infections, suggested that the first case of HIV infection occurred around 1930 in the West African region. The study, led by Dr. Bette Korber of the Los Alamos National Laboratory, is dependent upon a complex computer simulation of HIV evolution (“Avert”). Based on such incompatible scientific findings, it is highly likely that the HIV virus crossed over to humans on more than occasion; HIV presumably emerged simultaneously in different regions of the world. More radical theories put forth about the origin of HIV include a number of conspiracies suggesting that

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