How Did AIDS Evolve in Africa Essay Example | Topics and Well Written Essays - 1500 words

How Did AIDS Evolve in Africa - Essay Example In New York and California a number of men developed infections and cancers that resisted all known methods of treatment. The Human Immunodeficiency Virus was discovered soon after. (AVERT, 2009) However, while HIV was recognized only in the 1980s, there were several samples which, having only been recently analyzed, pre-dated this discovery. The samples, dated at the time they were taken, are as follows: 1. Dated 1959: Plasma sample, adult male from (the presently denominated) Democratic Republic of the Congo. The analysis here suggests the earliest known infection to have occurred in the 1940s or early 1950s. (Zhu, Tuofu, Korber & Nahinias, 1998) HIV is a lentivirus that attacks the immune system. The word â€Å"lentivirus† means â€Å"slow virus† because of the length of time it takes for the disease to manifest its ill effects on the human body. They are part of the larger classification of viruses known as retroviruses. Lentiviruses are found in many species of animals, but the one closest to the HIV is the Simian Immunodeficiency Virus (SIV), a strain that affects monkeys. It is accepted by a large number of experts that the HIV descended from the SIV because some strains of SIV appear closely similar to the two strains of HIV, the HIV-1 and HIV-2. The less virulent of these strains, the HIV-2, corresponds to a strain of SIV that is found in a species of monkey indigenous to western Africa, the sooty mangabey or white-collared monkey. The origins of the HIV-1 was more difficult to trace, but in 1990 a group of scientists found evidence that linked this strain to a sub-species of chimpanzees that inhabited m ostly west-central Africa. (AVERT, 2009) The Hunter Theory. Viral transfer can occur between species; when the transfer occurs between animals and humans, a â€Å"zoonosis† is said to have taken place. In the case of the HIV,