AIDS Essay Research Paper AIDS AIDS acquired

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AIDS Essay, Research Paper AIDS AIDS (acquired immunodeficiency syndrome) is a disease caused by a virus- HIV (human immunodiciency virus). The first cases in this country came to light in the early eighties. Although the origins of AIDS remains uncertain it is thought to have emerged decades ago in sub-Saharan Africa. There is a closely related virus (simian immunodeficiency virus, or SIV) that is found among monkeys in that particular area which AIDS is thought to have evolved from (Combating AIDS 353). When the virus first emerged in the United States it was localized to the male homosexual and IV drug user communities. This localization very quickly disappeared . AIDS is becoming a global epidemic. No country is safe from it. There has been AIDS cases reported around the

world, in such places as the Caribbean, Southeast Asia, Southeast Mediterranean , and Oceania. This helps to show that AIDS knows no geographical boundries (Folks). This disease has been likened to the Black Plaque that decimated Europe during the middle ages. By April 1984, scientists had identified the virus responsible for AIDS and by March 1995 developed a blood test for it (Combating AIDS 355). This quick progress in the battle even lead Heckler, the secretary of health and human services, to say that a cure was just a few years away. Today, no cure is available and no sure treatment for AIDS symptoms is at hand. People are still contracting and dying from AIDS at an alarming rate. AIDS is a fatal disease that does not kill the patient. Its principle source of infection is

the HIV virus which is a retrovirus. This means that the protein coat contains RNA instead of DNA and when the virus injects its genetic material into the host cell, it must first cause the cell to transcribe, using a unique enzyme called reverse transcriptase, it into complementary- DNA (c-DNA) before replication can occur. The virus is spherical in shape and is made of two parts: an envelop and core. The envelop is similar to a typical cell membrane (bilipid layer) imbedded with three proteins. The core section is bullet-shaped surrounded by a protein. Inside is the genetic material, RNA, covered by another protein (Combating AIDS 354). The HIV virus attacks the human helper T-cell or CD4-lymphocyte (part of the human immune defense system). This cell normally attacks and

destroys foreign proteins and viruses. The normal CD4 T-lymphocyte is impervious to the HIV virus but if this cell produces a CD4 receptor molecule the HIV virus then has an entry into the cell. It attaches to the CD4 receptors on the cell surface. A portion of the virus then penetrates the cell membrane, fuses with it and then the HIV virus injects its core into the cell. Proteins in the core cause the receptor cell to manufacture the viral c-DNA. This c-DNA then becomes a part of the cells genetic material. When this happens what is known as a provirus is formed. This provirus can remain unexpressed for years which is why a lot of HIV positive people do not show AIDS symptoms for years. When some activator stimulates the provirus, then viral RNA and the HIV proteins are

synthesized and new HIV viruses are produced (Nowak 964). When activated, the virus causes a suppression of the immune system so that one or more “opportunistic” diseases can gain a foothold. It is one of these diseases which eventually kills the patient. An “opportunistic ” disease is one which a normal person’s immune system can successfully defend against. When something occurs that damages the immune system, then these diseases abound (Folks). One of the symptoms of full blown AIDS is dementia. This was thought to be caused by encephalitis (inflammation of the brain). New evidence suggests that the AIDS virus itself destroys neurons in the brain even though it does not infect them. In laboratory findings the level of neurons in the brains of dead AIDS patients was