HIV / AIDS is one of the most prevalent and devastating diseases in the world today. It has already killed millions throughout the world, especially in developing countries like Africa. I chose this topic due to the importance of HIV for world heath issues and because of the larger social issues that this virus has for many countries. The statistics over the last decades are evidence of the growth and devastating effect of this virus. The total number of recorded deaths due to HIV / AIDS, between 1981 and 2003, was a staggering 20-million. The number of children in Sub-Saharan Africa who were orphaned by the end of 2003 was an estimated 12-million. Later figures indicate that the situation in Africa is not improving, with these figures increasing in 2004, especially among women in Africa. "By December 2004 women accounted for 47% of all people living with HIV worldwide, and for 57% in sub-Saharan Africa." (World HIV and Aids Statistics)
HIV / AIDS infect not only individuals but entire societies. " ... Aids migrated to man in Africa, it mutated into a complex plaque with ... social, economic and political dynamics that ... accelerate the virus' progress. (Death Stalks a Continent)
The Term HIV / AIDS refers to Acquired Immune Deficiency Syndrome, which is caused by the HIV virus. HIV refers to the Human Immunodeficiency Virus. AIDS itself refers to the complex of diseases that result from the HIV attack and intrusion on the human defense or immune system. The term syndrome means a "group of health problems that make up a disease." An individual is HIV positive when the body creates antibodies to fight the HIV virus. "When you get a blood test for HIV, the test looks for these antibodies. If you have them in your blood, it means that you have HIV infection. People who have the HIV antibodies are called "HIV-Positive." (What Is AIDS
There is therefore a connection but also a difference between being HIV positive, or having the HIV virus, and having AIDS.
Being HIV-positive, or having HIV disease, is not the same as having AIDS. Many people are HIV-positive but don't get sick for many years. As HIV disease continues, it slowly wears down the immune system. Viruses, parasites, fungi and bacteria that usually don't cause any problems can make you very sick if your immune system is damaged. These are called "opportunistic infections." (ibid)
Infection from the HIV virus is caused though direct transmission from person to person in a number of possible ways. The most common ways in which the virus is transmitted is though social contact with an infected person; though contaminated needles; and though transmission to a baby from an infected mother or though infected mother's milk. Infection through blood transfusions has also been recorded. However, in most countries blood transfusions are now more strictly controlled and screened and the risk of this mode of infection is extremely low.
The HIV Virus functions in the body by attaching to living cells. This relates to the fact that the virus cannot produce without parasitically attaching itself to a living cell in the body. The virus mainly targets an immune cell known as a lymphocyte; or more specifically "a CD4 helper cell, a type of T-cell." (Pieribone, D.)
The T-cell's are a vital part of the immune system as they facilitate the body's response and ability to combat many potential fatal infections. Without T-Cells the body is unable to provide the necessary degree of protection against opportunistic infections. The HIV's life cycle in effect reduces the amount of T-cells within the human body, which in turn results in greater susceptibility to infection. The process though which this occurs is not completely understood. (ibid) The HIV virus will in effect "hijack the T-Cells Cellular machinery" (ibid) and will then reproduce thousands of copies of the virus, which will invade more T-cells, further reducing the resistance of the body and increasing the propensity for opportunistic disease and full- blown AIDS. There are many steps before the process of viral duplication of the HIV virus is completed. An example of part of this complex process is as follows.
Once HIV comes into contact with a T-cell, it must attach itself to the cell so that it can fuse with the cell and inject its genetic material (a blueprint for making more HIV) into it. Attachment is a specific binding between proteins on the surface of the virus and proteins that serve as receptors on the surface of the T-cell. Normally, these receptors help the cell communicate with other cells. Two receptors in particular, CD4 and a beta-chemokine receptor (either CCR5 or CXCR4), are used by HIV to latch onto the cell. On the surface of the viral envelope, two sets of proteins (also known as antireceptors) called gp120 and gp41 attach to CD4 and CCR5/CXCR4. (Pieribone, D)
Initially, after a few weeks, once the amount of HIV in the blood increases there can be flu-like symptoms, but this is not the case with every infected individual. This initial stage is known as "acute infection." (Acute HIV Infection) Other symptoms that can indicate the presence of HIV include fever, fatigue, and rash as well as headache, swollen lymph glands, sore throat, feeling achy, nausea, vomiting, diarrhea, and night sweats. (ibid)
The infection by the HIV virus becomes AIDS when the immune system is seriously damaged and can no longer protect itself from infection. More specifically this occurs when the human body has less than "200 CD4+ cells or if your CD4+ percentage is less than 14% ... " (What is AIDS?: Aids Org) The most common opportunistic infections that the HIV patent can get include PCP (Pneumocystis pneumonia), KS (Kaposi's sarcoma), a form of skin cancer, CMV or Cytomegalovirus, as well as Candida, a fungal infection that can cause thrush. Aids related disease can also result in weight loss and brain tumors, as well as a host of other ailments. (ibid)
5. Prevention and Treatment
One of the ways that are being investigated to prevent HIV infection and to minimize its spread is based on the knowledge of how the HIV virus functions. Drugs which inhibit the virus and block its ability to gain access to the T-cells are being developed. These are known as attachment or early inhibitors.
These drugs block the interaction between the cellular receptors and the antireceptor on the virus by binding to or altering the receptor sites .... Scientists are also examining vaccines that may help the body block these receptors. (Pieribone, D.)
The only prognosis for full-blown AIDS at present is eventual deterioration of the immune system (usually five to ten years) culminating in death. There is no cure for the disease, yet there are a number of drugs on the market and in development that can retard and slow the development of the virus.
Antiretroviral treatment is at present the best way of retarding the spread of the HIV virus in the body. It is not a cure but it can help to prolong life and stop the spread of the virus. There are three main groups of anti-HIV drugs that are presently used to combat the virus. Each of these groups attacks the virus in different ways. These are the Nucleoside Reverse Transcriptase Inhibitors; the Non-Nucleoside Reverse Transcriptase Inhibitors and the Protease Inhibitors. (ibid)
Anti-HIV or antiretroviral medications are used only to control the reproduction of the virus and to slow the development of the disease. Usually treatment consists of a combination of two to three Anti-HIV medications together. It should also be noted that anti-HIV drugs do not strop the ability of the infected person to contaminate others.
The following are some of the most well-known Anti-HIV classes and medications which have been approved by the U.S. Food and Drug Administration (FDA).
NNRTI's bind to and disable reverse transcriptase, a protein that HIV needs to make more copies of itself. (Approved Medications to Treat HIV Infection) This group includes the following generic brands.
Nevirapine, under the brand name Viramune is the most well-known compound. It requires a daily dosage for adults of 200mg 2X daily. (Background Information on Fourteen FDA Approved HIV / AIDS Drugs.) Delavirdine requires a higher dosage of 400mg 3X daily, while Efavirenz requires 600mg 1X daily
'NRTIs are faulty versions of building blocks that HIV needs to make more copies of itself. When HIV uses an NRTI instead of a normal building block, reproduction of the virus is stalled." (ibid) These include numerous generic brands. One of the most well- known medications in this group is Zidovudine or AZT. The normal adult dosage is 200mg 3X daily, or 300mg 2X daily. (ibid) Another drug in this group is Didanosine or DDL. The adult dosage for this medication is 200mg 2X daily ( ibid)