Biology of STDs Essay Example | Topics and Well Written Essays - 1750 words

Biology of STDs - Essay Example Let us first examine an STD that remains a frightening epidemic and is usually a slow death sentence: "It is estimated that 14 million people worldwide are infected with HIV, and there were 2.5 million documented AIDS cases in early 1993" (Nye 1). "HIV attacks the type of lymphocyte known as helper T cells." (Mader 908) HIV (human immuno deficiency syndrome) is a member of the retrovirus family. It is called a retrovirus because it is in a class of viruses which literally imbed themselves into host DNA. It is important to note that any virus that alters DNA can also cause cancer. The altering of host DNA is done when the viral RNA undergoes a process which is almost inverse to DNA and RNA transcription in normal cell division. This reverse process works when an enzyme called reverse transcriptase synthesizes is used by the viral RNA to produce a DNA strand. It is this strand that ultimately becomes part of host DNA. When that host DNA is then transcribed into viral proteins from mRNA , the virus essentially is then a part of the host DNA. Once this takes place, the virus begins affecting the host's immune system. The HIV virus binds to markers on immune system cells called CD4 markers. Once an individual is infected with HIV, their immune system is progressively annihilated by the virus. The paradox of HIV is that while the immune system cells effectively destroy virus particles, the virus continues to reproduce itself such that more viral particles are produced. In addition, the immune system continues to destroy cells infected by the virus but more cells are then produced as replacements. This continues until the patient does not regenerate as many immune system cells such as T cells. Eventually, the patient becomes infected with something as simple as the common cold or flu and does not have the immune system capabilities to fight it off. This often results in death. There are in fact three stages to AIDS. They are referred to as categories A-C. From the time of infection through year 1 is represented as category A. This is a time of little to no symptoms, but the spreading the disease through sexual activity to others is likely. Category B is characterized by flu like symptoms, swollen lymph nodes and herpes-like outbreaks. This period lasts about 8 years. It is during category C that patients are considered to have "full blown AIDS" and typically fall victim to infections that become lethal. There are new drugs on the market that AIDS patients can take to prolong their life span to some degree. Not all sexually transmitted diseases are as aggressive and life threatening as HIV and AIDS but can still cause irreparable damage to the patient. An example of this is Herpes. This virus remains in the body indefinitely. There are two types of Herpes. Herpes Simplex Virus 1 and Herpes Simplex Virus 2. The fist kind of herpes is usually responsible for cold sores while the type 2 form causes genital lesions or genital herpes. Type 2 herpes is more sever and also less common. Type one herpes is spread through mucous membranes when infected partners engage in oral sex. The herpes virus usually takes between 4 and 10 days to incubate. In occurrences of breakouts, lesions form which fill with fluid. This fluid's content is cells which have been infected with the virus as well as inflammatory cells. The fluid