The human immunodeficiency virus (HIV) is believed to be the virus that causes Acquired Immunodeficiency Syndrome (AIDS), a deadly disease that affects nearly one million Americans every year (Silverstein, 1991).
HIV is classified as a retrovirus that uses RNA templates to produce DNA. For example, within the core of HIV, a double molecule of ribonucleic acid, RNA, exists. When the virus invades a cell, this genetic material is replicated in the form of DNA.
However, in order to produce this DNA, HIV must first be able to produce a particular enzyme that can construct a DNA molecule through a RNA template. This enzyme, known as RNA-directed DNA polymerase, is also referred to as reverse transcription because it reverses the typical cellular process of transcription.
The DNA molecules created by reverse transcription are then placed in the genetic material of the host cell, where they are co-replicated with the host's chromosomes. As a result, they are distributed to all daughter cells during subsequent cell divisions. The virus then produces RNA copies of its genetic material. These new HIV clones become covered with protein coats and leave the cell to find other host cells to repeat the process.
The HIV virus, like many other viruses, targets particular types of cells in the body and occupy them. HIV targets the T cells of the immune system, as well as the brain, nervous system, digestive system, lymphatic system, and other areas of the human body.
The immune system consists of specialized cells, which fight off germs in an effort to maintain a healthy body (Aronstein, 1998). The "T" cells are the brains of the operation. These tiny white blood cells identify invaders and alert soldier-type cells, which then fight various bacteria, viruses, cancers, fungi, and parasites that can damage the body.
The main goal of the HIV virus is to reproduce itself. When it attacks and invades a T cell, it converts that cell into a small virus factory. Eventually, so many new viruses are located in the cell that the T cell explodes, pushing the HIV back into the bloodstream. The virus then invades fresh T cells and repeats its mission. Eventually, the HIV virus can destroy all of an infected person's T cells.
How HIV is Spread
HIV is basically spread through the exchange of bodily fluids, such as blood and semen (Silverstein). In most cases, HIV from the bodily fluids of infected men and women enters the bloodstream of an uninfected person during unprotected sex. However, unprotected sex is not the only way that the disease is spread.
A person can be infected with HIV as a result of sharing needles or syringes, which provide direct exposure to the blood of an infected individual. Many drug users are infected this way, as they often inject needles into their veins (Folks, 1998, p. 4).
In addition, a mother who has HIV can transmit the disease to her baby, before or during childbirth, or through breast-feeding. However, research shows that only 25 to 35% of babies born to HIV-infected mothers around the world become infected this way (p. 6). Still, this method of infection is responsible for 90% of all cases of HIV in children.
HIV has also been passed along through open mouth kissing, as well as sharing fluids, toothbrushes and razors.
Detection and Diagnosis
In the 1980's, a blood test was invented that could detect traces of HIV in the bloodstream (Aronstein). The original test would show whether a person's blood held antibodies against HIV, which indicated that the person was exposed to the virus.
In the 1990's, an additional blood test was created to detect HIV antigens, enabling doctors to identify HIV even before a person's immune system had time to make antibodies.
The Center for Disease Control and Prevention's authoritative definition for the diagnoses of AIDS concludes that the CD4 T-cell count in an HIV positive person must be below 200 cells per cubic mm of blood, or there must be a clinical appearance of an initial AIDS-defining opportunistic infection, such as PCP (a type of pneumonia), oral candidiasis, pulmonary tuberculosis, or invasive cervical carcinoma (cancer in the cervix of women) (Virginia Silverstein 23).
Symptoms of HIV
During the first stages of HIV, most people experience few or no symptoms of the disease (Cohen, 1999). According to studies, the majority of people infected with HIV show temporary, gentle symptoms immediately upon affection. However, most dismiss these symptoms as a few or…