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HIV
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HIV

The human immunodeficiency virus (HIV) is a frequently mutating retrovirus that attacks the human immune system and which has been shown to cause acquired immune deficiency syndrome (AIDS).

Table of contents
1 History
2 Pathogenesis
3 Treatment
4 Common myths regarding HIV
5 External Links
6 Topics to be covered

History

HIV was discovered and identified as the agent for AIDS by Luc Montagnier of France.

A minority of scientists continue to question the connection between HIV and AIDS and even the very existence of HIV (see AIDS reappraisal).

As of 27 November 2003, there were an estimated 54,862,417 worldwide HIV infections, 30% of which were in Southern Africa.

Pathogenesis

HIV causes disease by infecting the CD4+ T cells. These are a subset of leukocytes (white blood cells) that normally coordinate the immune response to infection. By using CD4+ T cells to replicate itself, HIV spreads throughout the body and at the same time depletes the very cells that the body needs to fight the virus. Once an HIV-positive individual's CD4+ T cell count has decreased to a certain threshold, they are prone to a range of diseases that the body can normally control. These opportunistic infections are usually the cause of death.

There are several reasons why HIV is so hard to fight. First, the virus is an RNA virus, using the reverse transcriptase enzyme to convert its RNA into DNA. During that process there is a large chance of mutation. Therefore, the virus becomes quickly resistant to therapy. Second, the common notion that HIV is a killer feasting on T cells is not true. If HIV were a killer virus, it would have died out soon because there would be too little time for new infections. Now, HIV stays in the body for years, infecting people through unsafe sex, blood transfusions and breastfeeding of infants while the patient sometimes doesn't know. HIV can survive even when drugs eliminate all detectable virons in the blood. It integrates itself into the DNA of the host cell and can stay there for years, lying dormant, immune to all kinds of therapy because it is just DNA. When the cell divides and the DNA is copied, the virus is copied too. After years, the virus can become active again, seize the cell's machinery and replicate. In recent years, the notion that the CD4+ T cells decrease because of direct HIV infection has become doubted as well. The HIV coating protein readily detaches from virus particles. The blood becomes filled with these proteins, which can stick to the CD4+ T cells, gluing them together. In addition, they are recognized by the immune system, causing the immune cells to attack their own CD4+ cells. In summary, HIV is a guerrilla terrorist, keeping low and seeking shelter when threatened, but always ready to hit where it hurts.

Treatment

. AZT, a reverse transcriptase inhibitor, was the first treament for HIV]]

Patients today are given a complex regimen of drugs that attack HIV at various stages in its life cycle. These are known as antiretroviral drugs. They include:

Many problems are involved in establishing a course of treatment for HIV. Each effective drug comes with side effects, often serious and sometimes life-threatening in themselves. Common side effects include extreme nausea and diarrhea, liver damage and failure, and jaundice. Any treatment requires regular blood tests to determine continued efficacy (in terms of T-cell count and viral load) and liver function.

Common myths regarding HIV

External Links

Topics to be covered

To be written:

See also:
Other HIV/AIDS related articles in Wikipedia
HIV | AIDS
HIV test | HIV vaccine
AIDS in Africa | AIDS in America
AIDS myths and urban legends | AIDS reappraisal | AIDS conspiracy theories
NAMES Project AIDS Memorial Quilt | List of HIV-positive individuals