Tuesday, September 3, 2019

A Reading Reaction to My Brother Sam is Dead :: essays research papers

Report On AIDS   Ã‚  Ã‚  Ã‚  Ã‚  AIDS( Acquired immune deficiency symdrome) is caused by infection with the human immunodeficiency virus(HIV) which attacks selected cells in the immune system and produces defects in function. These defects may not be apparent for years. They lead to a severe suppression of the immune system's ability to resist harmful organisms. This leaves the body open to invasion by various infections.   Ã‚  Ã‚  Ã‚  Ã‚  The first cases of AIDS were reported in the early 1980s. From 1981 to 1998 more than 700,000 AIDS cases and more than 400,000 deaths have been reported in the United States. It is estimated that nearly 1 million Americans have been infected through the late 1990s but nt have yet developed clinical symptoms. In 1997 the United Nations announced that it had underestimated the spread and revised the estimate of people living with the disease from 22 million in 1996 and 30 million in 1997. The origin of the AIDS virus is uncertain but may have originated in Central Africa.   Ã‚  Ã‚  Ã‚  Ã‚  The first AIDS patients in the Americas and Europe were almost exclusively male homosexuals and bisexuals. Others received AIDS from blood transfusions, hemophiliacs and drug users or females whose male sexual partners had AIDS. Since 1989 heterosexual was found to be the fastest growing means of transmission of the virus.   Ã‚  Ã‚  Ã‚  Ã‚  American researchers named the virus that causes AIDS the human T-lymphotropic virus, typee III or HTLV-III. In the late 1980s they discovered several forms of the AIDS virus. It was renamed the human immunodeficiency virus type 1, or HIV-1. The virus enters the bloodstream and destroys certain white blood cells called T lymphocytes or T cells. The T cells play a very important role in the functioning of the immune system. The virus can affect other types of cells in the body such as macrophages. Macrophages are not killed by the virus but T cells are. Research has suggested that macrophages may carry the AIDS virus to healthy brain cells to the lymphatic system.   Ã‚  Ã‚  Ã‚  Ã‚  When the AIDS virus enters the bloodstream, the body's immune system produces antibodies to battle the microorganism. Blood tests can detect these antibodies and therefore can indicate exposure to the virus. Sometimes these tests give false readings and can only begin to give accurate results within two weeks to three months after infection. During that time an infected person may pass the virus to others. Scientists are still uncertain how the AIDS virus damges the immune system.

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