Bibliography: This is my first Biology paper. My major is Psychology. I attend an university in Maryland part-time. I am a college Sophomore. I work in Communications.

UNDERSTANDING THE AIDS VIRUS

Will I live to see tomorrow? Is there a hope for the future? These are probably the most commonly asked questions among AIDS patients today. This paper delves into the heart of the AIDS topic by giving a detailed definition of the virus, risk factors associated with transmission, and the best treatment methods studied by the Centers for Disease Control, the National Institutes of Health, and other research organizations.

AIDS. The word alone strikes fear into every sexually active individual. Why is this? The reason is that everyone can relate to the consequential symptoms of the disease, but not everyone knows the real meaning of AIDS. AIDS is an acronym for "Acquired Immunodeficiency Syndrome." The Centers for Disease Control defines AIDS as the presence of at least one of several opportunistic diseases, along with infection by the human immunodeficiency virus (HIV). An opportunistic disease is described as a disease that has an opportunity to occur because the immune system has been weakened. Examples of opportunistic diseases would be Pneumocystis carinii pneumonia, Kaposiís sarcoma, or toxoplasmosis. The combination of such diseases, plus HIV, deplete the complex natural defense system protecting the body from infection by viruses and microorganisms. The definition of AIDS has also been expanded to include a CD4+ T cell count less than 200 cells per cubic millimeter (mm3) of blood.

AIDS is characterized by the progressive loss of the CD4+ helper cell, a type of white blood cell that helps the body fight off certain infections. This cell is also known as the T, T-helper, and T4 cells. The CD4+ cells are white blood cells that stimulate B lymphocytes to produce antibodies, lead to a severe reduction of functions of the bodyís immune system (immunosuppression), neurological complications, and opportunistic infections that rarely occur in persons with intact immune function. Although the precise causes leading to the destruction of the immune system have not been fully discovered, the detailed studies of epidemiology, virology, and immunology support the conclusion the HIV is the underlying cause of AIDS; hence HIV invades and destroys the CD4 cells.

Primary HIV infection is often associated with as abrupt decline of CD4 cells in the peripheral blood. The decrease in circulating CD4 cells during primary infection is probably due to two factors: 1) depletion by HIV, and 2) to redirect cells to the lymphoid tissue and other organs. The median period between the infection of HIV and the onset of clinically apparent disease is approximately 10 years in western countries, according to prospective studies of homosexual men. This period also applies to HIV-infected blood transfusion recipients, injection drug users, and adult hemophiliacs.

In 1981, clinical investigators in New York and California observed among young, previously healthy, homosexual men a strange clustering of cases of rare diseases, notably Kaposiís sarcoma (KS) and opportunistic infections such as Pneumocystis carinii pneumonia (PCP), as well as cases of unexplained, persistent lymphadenopathy. It soon became evident that these men had a common immunologic deficit- the impairment in cell mediated immunity, resulting from a significant loss of CD4 cells. The widespread development of KS and PCP in young people with no previous history of disease was
unusual. After detailed studies and searches of autopsy records, medical history books, and tumor recordings, results showed that KS and PCP had only occurred at very low levels in the United States previously.

KS, Kaposiís sarcoma, is a skin neoplasm that affected older men, cancer, or transplant patients undergoing immunosuppressive therapy. Before AIDS became a big issue, the only reports of KS in the United States were 0.02 to 0.06 per 100,000 population. In addition, the disease was generally found in certain parts of Africa among younger individuals. By 1984, men in San Francisco were found 2,000 times more likely to develop KS! By 1994, at least a whopping 36,693 patients with AIDS had been reported. This shows how fast the spread of the disease takes place.

PCP, Pneumocystis carinii pneumonia, a lung infection caused by a pathogen, was extremely rare before 1981. Taken from a survey in 1967, only 107 cases had been reported and documented in medical literature. In that same