Aids 2 Essay Research Paper AIDSAcquired immune
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Aids 2 Essay, Research Paper AIDSAcquired immune deficiency syndrome, or AIDS, is adisease entity that has been recognized since 1981. It is caused byinfection with the human immunodeficiency virus, which attacksselected cells in the immune system and produces defects infunction. This leaves the body open to an invasion by variousinfections, which are therefore called opportunistic diseases, andto the development of unusual cancers. The virus also tends toreach certain brain cells. Since the first AIDS cases werereported in 1981, through mid-1991, more than 190,000 AIDScases and more than 120,000 deaths had been reported in about162 countries worldwide. Sub-Saharan Africa in particularappears to suffer a heavy Berden of this illness. So far there is nocure or vaccine that exists for AIDS, but scientists belive a man bythe name of Dr. David Ho has discovered a cure. HIV infectionand AIDS represent one of the most pressing public policy andpublic health problems world wide.Definition of AIDSthe U.S Center for disease control has established criteriafor defining cases of AIDS that are based on laboratory evidence,the presence of opportunistic diseases, and a range of otherconditions. Other complications of HIV infection include fever,diarrhea, severe weight loss, and swollen lymph nodes. WhenHIV-infected persons experience some of the above symptoms butdo not meet full criteria for AIDS, they are given the diagnosis ofAIDS-related complex, or ARC. Historical BackgroundIn the late 1970s, certain rare types of cancer and a verietyof serious infections were recognized to be occurring in increasing numbers of previously healthy persons. First formally describedin 1981, the syndrome was observed predominantly to be affectinghomosexual and bisexual men. Soon thereafter, intravenous drugusers, hemophiliacs, and recipients of blood transfusions wererecognized as being at increased risk for disease as well. Furtherstudy of AIDS patients revealed marked depletion of certainwhite blood cells, called T4 lymphocytes. Then, in 1983, a T-celllymphotropic virus was separately discovered by Robert Gallo atthe U.S National Institutes of Health and Luc Montagnier atFrance s Pasteur Institute. Modes of TransmissionResearchers have isolated HIV from a number of bodyfluids, including blood, semen, saliva, tears, urine, cerebrospinalfluid, breast milk, and certain cervical and vaginal secretions.Strong evidence indicates, however, that HIV is transmitted onlythrough three primary routes: sexual intercourse, either vaginalor anal, with an infected individual; nondigestive exposure toinfected blood or blood products; and from an infected mother toher child before or during birth. At least 97 percent of U.S AIDScases have been transmitted through one of the routes, withtransmission between homosexual men accounting for about 60percent of AIDS cases. About 21 percent of AIDS cases occur inintravenous drug abusers exposed to HIV infected throughsharing needles. The number of new cases of AIDS inreproductive age is increasing at an alarming rate. AIDS hasbecome the leading cause of death for women between the ages of20 and 40 in major cities of North and South America, WesternEurope, and Sub- Saharan Africa.