Aids Essay Research Paper AidsAcquired Immune Deficiency

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Aids Essay, Research Paper Aids Acquired Immune Deficiency Syndrome (AIDS), suppresses the immune system related to infection with the human immunodeficiency virus (HIV). A person infected with HIV gradually loses immune function along with certain immune cells called CD4 T-lymphocytes or CD4 T-cells, causing the infected person to become vulnerable to pneumonia, fungus infections, and other common ailments. With the loss of immune function, a clinical syndrome (a group of various illnesses that together characterize a disease) develops over time and eventually results in death due to opportunistic infections (infections by organisms that do not normally cause disease except in people whose immune systems have been greatly weakened) or cancers. In the early 1980s deaths by

opportunistic infections, previously observed mainly in organ transplant recipients receiving therapy to suppress their immune responses, were recognized in otherwise healthy homosexual men. In 1983, French cancer specialist Luc Montagnier and scientists at the Pasteur Institute in Paris isolated what appeared to be a new human retrovirus?a special type of virus that reproduces differently from other viruses?from the lymph node of a man at risk for AIDS. Nearly simultaneously, scientists working in the laboratory of American research scientist Robert Gallo at the National Cancer Institute in Bethesda, Maryland, and a group headed by American virologist Jay Levy at the University of California at San Francisco isolated a retrovirus from people with AIDS and individuals having

contact with people with AIDS. All three groups of scientists isolated what is now known as human immunodeficiency virus (HIV), the virus that causes AIDS. Infection with HIV does not necessarily mean that a person has AIDS, although people who are HIV-positive are often mistakenly said to have AIDS. In fact, a person can remain HIV-positive for more than ten years without developing any of the clinical illnesses that define and constitute a diagnosis of AIDS. In 1996 an estimated 22.6 million people worldwide were living with HIV or AIDS?21.8 million adults and 830,000 children. The World Health Organization (WHO) estimates that between 1981, when the first AIDS cases were reported, and the end of 1996, more than 8.4 million adults and children had developed AIDS. In this same

period there were 6.4 million deaths worldwide from AIDS or HIV. About 360,000 of these deaths occurred in the United States. Clinical Progression of AIDS The progression from the point of HIV infection to the clinical diseases that define AIDS may take six to ten years or more. This progression can be monitored using surrogate markers (laboratory data that correspond to the various stages of disease progression) or clinical endpoints (illnesses associated with more advanced disease). Surrogate markers for the various stages of HIV infection include the declining number of CD4 T-cells, (the major type of white blood cell lost because of HIV infection). In general, the lower the infected person?s CD4 T-cell count, the weaker the person?s immune system and the more advanced the

disease state. In 1996, it became evident that the actual amount of HIV in a person?s blood?the so-called viral burden?could be used to predict the progression to Aids, regardless of a person?s CD4 T-cell count. With advancing technology, Viral Burden Determinations are quickly becoming a standard means of patient testing. An infected person?s immune response to the virus?that is, the person?s ability to produce antibodies against HIV? can also be used to determine the progression ofAids; however, this surrogate marker is less precise during more advanced stages of AIDS because of the overall loss of immune function. Within one to three weeks after infection with HIV, most people experience nonspecific flulike symptoms such as fever, headache, skin rash, tender lymph nodes, and a