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Aids Essay Research Paper AIDS from ChimpanzeesScientists

Aids Essay, Research Paper

AIDS from Chimpanzees?Scientists have discovered that the virus that causes AIDS started in a certain type of chimpanzee from Africa. The scientists compared HIV (human immunodeficiency virus) in humans to SIV (simian immunodeficiency virus) in chimpanzees. The tests showed that SIV crossed over the species barrier and began infecting humans. The research was done by a group of scientists from the United States, France, and Great Britain. This team of scientists believes that the virus jumped the barrier when humans in Africa handled the blood or meat of infected chimpanzees.Many people began killing that type of chimpanzee, hoping to stop the spread of the AIDS virus. But the scientists have stopped them from killing any more chimps. They need the chimpanzees to live. They need to study why the chimpanzees who carry SIV do not die from AIDS. The scientists hope that they will find a cure for AIDS and a vaccine which will prevent more humans from getting the AIDS virus.These are ways that HIV can be passed:From person to person through unprotected sex with a person who is HIV infected.From one person to another, through the sharing of needles for drugs. Sometimes, medical personnel who work with HIV-positive patients may be pricked by a needle that has been infected.From a mother to her baby, during pregnancy.Through breast-feeding, from the mother’s milk. Only about 1/3 of babies of HIV-positive mothers are infected this way. These are ways that HIV cannot be passed: From mosquito bites or insect bites. From a toilet seat in a public restroom. From going to the same school with someone who is has AIDS. From visiting or talking to a friend who is sick with AIDS. From hugging a friend who has HIV/AIDS. It is impossible to catch AIDS just by being kind to someone who has AIDS. The information provided is for educational use only. It is not intended for, and should not replace, the advice and treatment of a qualified physician. Question: Can you tell me how the AIDS virus was spread from Africa to the United States and why it spread so rapidly? HIV probably arose in Africa as a zoonotic infection that succeeded in jumping from non-human primates to man. The most likely candidate at this point is SIV, or Simian Immunodeficiency Virus. This is a virus that produces a disease very much like AIDS in monkeys, and is both structurally and genetically related to HIV. According to Laurie Garrett (”The Coming Plague”) and others, it is speculated that HIV is sort of like other emerging diseases, like Ebola, in that they have existed in animal populations for a long time, but man did not come into contact with them until humans penetrated the formerly uninhabited regions of the jungle/rain forest where these things were found. Probably there were chance infections in earlier times as well; but populations were far smaller, sparser, more separated, and travel more difficult. Today, with modern air transportation, with roads such as the Kinshasa Highway in Zaire, with rapid movement of large numbers of people into and out of Africa and around the world, these emerging diseases have exactly what they need to get started in a big way: large, high-density, non-immune populations fairly close together and a very efficient and high speed means of moving infected individuals between populations. As man encroaches on these, we encounter these (to us) new viruses. Some cannot make the jump, because we are not susceptible. Others make the jump, but do not cause illness. Some make the juocause illness. Some make the jump are immediately lethal, such as Ebola. Still others make the jump, and change to fit the new host.

A great deal has been made of “patient zero,” a gay flight attendant, who was traced by classic epidemiological methods to an early cluster of AIDS patients in the United States (detailed in “And the Band Played On” by Randy Stoltz). There were probably other “patient zeros” as well who remain unknown. Clearly, the long latency of infection and the ready spread through unprotected sexual contact, coupled with a fairly high degree of promiscuity in some segments of the gay population during the 1970s and 1980s, have had a lot to do with establishing the virus in the United States. We must remember, however, that HIV has a very different demographic distribution in Africa and parts of Asia, where heterosexual transmission is the predominant mode of transmission; and the incidence of infection is the same in men and women. Further, while homosexual and bisexual men still account for almost half of all new cases, heterosexual transmission and transmission to women are increasing rapidly and represent the fastest growing population of new AIDS cases. In addition, IV drug use, and associated prostitution are major problems and are very efficient ways to move the virus into new patients, who then move the virus.The information provided is for educational use only. It is not intended for, and should not replace, the advice and treatment of a qualified physician.Question: What is the history of AIDS?This is a young disease by historical perspective. It supposedly first appeared in humans in 1976 but was not recognized as a disease until 1981. There are numerous theories regarding the origins of the HIV virus. There is a relationship between HIV, Human Immune Deficiency, and SIV, Simian Immune Deficiency (monkeys). The disease originated in Africa, where tropical diseases and malnutrition run rampant. In Africa, the transmission has always been among the heterosexual population. In the United States, it appeared simultaneously in New York and California. Case #2, before the disease being recognized, was a gay flight attendant who had numerous partners throughout the world. Supposedly, this person helped the disease significantly spread throughout the world. In 1979, the term for the syndrome was GRID Gay Related Immune Deficiency. By 1981, people were dying from GRID in epidemic proportions, with Kaposi’s Sarcoma and PCP, Pnemocystic Carni Pneumonia. In 1982, the term AIDS came into use. In 1983, the term ARC, AIDS Related Complex, was used. This was later discarded. In 1985, antibody testing with the Elissa and Western blot was utilized. To this date, there is no cure in sight.The information provided is for educational use only. It is not intended for, and should not replace, the advice and treatment of a qualified physician.




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