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Aids: The Millenial Bug Essay, Research Paper
AIDS: THE MILLENIAL BUG
January 1, 2000
INTRODUCTION
At the beginning of the 20th Century it was believed by many, including the United States Patent Office, that there was nothing else to invent. Now, 100 years later at the beginning of the new millenium the ancient Egyptian philosopher is more relevant, “there is nothing new under the Sun”. While HIV/AIDS may be a new disease, there is nothing new about a novel epidemic, which can potentially or actually decimate a population. In the late middle ages, the Black, now known as the Bubonic Plague, swept through Europe killing virtually half the population. It was introduced by a single or small group of rats that came to Italy abroad a trading ship from what is now Turkey. Small Pox transmitted by trade goods from the Hudson Bay Company wiped out entire Native American tribes. There are other examples of diseases accidentally introduced to a population that had no genetic immunity to them. Not to mention NASA’s fear of an unbeatable super virus from outer space. Now as in previous diseases, one of the dangers of HIV/AIDS is not only in its plague proportions but also in the almost superstitious misunderstanding of the virus itself.
In the treatment of all illness, it is necessary to understand the emotional, economic, psychological and sometimes even political impact that is brought about by the disease. This is particularly true with a disease that is as devastating and heretofore misunderstood as HIV/AIDS.
AIDS is the punishment of God on sinners. AIDS is a plot by the CIA and the South African Government to wipe out the population of black Africa. AIDS is the result of medical experimentation during the development of the polio vaccine employing the use of rieces monkeys as guinea pigs. AIDS is this, AIDS is that; AIDS is the end of the world. There is nothing new under the Sun. As we enter a new millenium, we are still controlled by prejudice, fear and superstition. AIDS is not the end of the world, it is simply the latest challenge the medical community needs to meet. There are new things to invent including an immunization and cure for HIV/AIDS. But before that we must overcome the age-old superstitious fears of the unknown and rise above the prejudices that we harbor of, “those people”. Let us understand HIV/AIDS.
AIDS, the acronym for acquired immunodeficiency syndrome, is the end stage disease of the human immunodeficiency virus (HIV). The result of this disease is the destruction of the patient’s immune system. Since the infected person has no ability to fight off any infection because the virus is replicating in and destroying the cells that normally fight infection, he/she then becomes susceptible to all opportunistic disease. Ultimately death occurs as a result of the body’s inability to fight infection.
In the early 1980″sThe Center for Disease Control and Prevention became aware that a new “virus” was effecting certain segments of society. In 1985 researchers isolated a virus believe to be responsible for AIDS. Since that time the definition of this disease has changed many time. In 1993 the definition was expanded to include conditions more applicable to women and injecting illegal drug users. The new definition includes all HIV infected persons who have a CD4 cell count of 200 cells per microleter of blood. Also added were three clinical conditions. The current definition states that AIDS is an illness characterized by laboratory evidence of HIV infection coexisting with one or more indicator diseases. Most patients are diagnosed by these criteria.
HIV, as its name indicates is a virus and is therefore and obligate parasite. Such parasites can only replicate while inside another living cell, or host. Parenthetically, HIV carries its genetic material in RNA rather than DNA, and while in the host the virus converts RNA to DNA in order to replicate. In seeking hosts, HIV is typically attracted to cells with CD4 + molecules on their surface such as T-helper lymphocytes and similar cells. HIV reproduces at a phenomenal rate, which causes massive destruction to the host cells. Cell destruction grows geometrically as the virus replicates and seeks new host cells. Immune system breakdown primarily results from the dysregulation and destruction of T-helper cells or CD4+lymphocytes.
HIV is particularly sinister in its attack on T-helper cells since one of the functions of those cells is to recognize and alert the immune system to alien infections Initially the body’s immune system, to a certain degree combats the virus. However, since the virus virtually targets CD4+lymphatics or T-helper cells, the immune system begins to loose its ability to even recognize let alone defend the invading virus.
The immune system remains relatively healthy as long as its count of CD4 cells is greater than 500 per microliter of blood. Since CD4 + cells are designed to attack infection, they are ironically drawn to the virus where they are subsequently infected. Ultimately the infection spreads through the lymph system and lymphoid tissue becomes a reservoir for HIV replication. As the disease progresses viral particles begin to enter the blood, this results in the infection of body tissues where the virus begins to replicate in infected macrophages. Massive reproduction of HIV in these cells causes the macrophage to burst allowing HIV to infect surrounding tissues. The skin, lymph nodes, CNS, lungs and possibly even bone marrow are infected in this manner. The virus at this point is well on its way to infecting every organ and tissue in the body.
The symptoms of HIV, while highly identifiable to the patient, are general in nature and are attributable to any number of causes. Early signs are consistent with flu like viruses. They include abdominal pain, chills and fever, coughing, diarrhea, dyspnea, fatigue and headache. Later symptoms are more severe and could be consistent with other diagnosis including cancer. Some symptoms include disorders of the lymphatic system, malaise, muscle and joint pain, night sweats, oral lesions, shortness of breath, skin rash, sore throat, weight loss and disorientation. Additionally in the majority of HIV cases there are neurological manifestations as well.
In addition to symptoms preliminary diagnosis can be made by deduction in ascertaining whether or not the patient engages in high-risk behaviors. If combinations of symptoms are present and are accompanied by high-risk behaviors, then immediate clinical testing is advised.
The individual’s blood is tested with ELISA or enzyme immunoassay (EIA), antibody tests that detect the presence of HIV antibodies. If this test is positive than the same blood is tested a second time. If a second EIA test is positive a Western blot is performed. This is a more specific confirming test. Blood that tests positive to all three screenings is reported to be positive for HIV. IF the results are inconclusive or indeterminate, the tests are repeated in 4 to 6 weeks. Again, if repeated and the results remain indeterminate a culture is done to determine the viral load, this is done through testing the DNA of the individual. These tests, whether positive or negative does not confirm nor dismiss the diagnosis of AIDS. That is done according to the 1993 CDC definition of HIV. A negative test is not an assurance that the individual is free of HIV since seroconversion takes up to three months after initial infection. And if the individual continues to engage in risky behaviors, transmission of the disease is likely to occur.
At the present time it is believed that the modes of transmission of the HIV virus are clearly identified and understood. Although generally perceived by the public as a sexually transmitted disease, the method of HIV transmission is far broader than simple sexual contact. As previously stated an obligate virus HIV requires a host organism to survive. Once leaving the human body the virus is extremely fragile and cannot survive outside of a host. Thus, HIV is transferred from person to person through infected body fluids including blood, semen, cervicovaginal secretions, breast milk, pericardial, synovial, cerebrospinal, peritoneal and amniotic fluids.
It has been discovered that not all body fluids, which contain HIV, transmit the virus. These fluids include saliva, urine, tears and feces. Further, the ability for HIV to be transmitted via an infected fluid from one human to another is mitigated by a variety of variables such as duration and frequency of exposure, the amount of the virus inoculated and the virulence of the organism. The efficiency of the immune system is also a factor. Once the virus has been passed to another individual, the newly infected individual then is immediately capable of passing the virus to yet another individual. However, there are apparently cycles when the probability of transmission is greater than others. The greatest potential for transmission occurs immediately after infected and during their end stages of the disease. Nonetheless, it must be stressed that it is possible for HIV to be transmitted at anytime during the entire disease spectrum.
As a practical matter, the most common method of transmission of HIV is through sexual contact. Vaginal and anal intercourse are two of the three most common modes of HIV transmission. Throughout the world it is believed that 75% of the total AIDS cases were the result of sexual contact. Anal intercourse is the most frequent method of HIV transmission. This being the result of the frequent tearing of the rectal mucosa which allows for direct infusion of the infected semen into the blood stream.
In all cases of intercourse the receptive partner is far more susceptible than the insertive partner. This is not only true of anal and vaginal intercourse, but also for oral intercourse as well. HIV can also be transmitted through oral genital sexual contact but such cases are considered rare. The homosexual community was seriously impacted by HIV in the early days of the epidemic. This was the result of the tendency for unprotected and casual sexual encounters as well as a higher tendency for anal intercourse. The prostitution subculture was and still is seriously impacted by the HIV virus. Causes of this include their numerous and varied sexual encounters, pre-existing sexually transmitted diseases in addition to life style issues such as alcohol, smoking and illegal drug use which weakens the immune system.
Undoubtedly, the most powerful form of transmission from one human to another of the HIV virus is through direct blood transfusions employing infected blood. However, this has resulted in a miniscule number of cases. But the accidental or intentional use of contaminated injecting equipment is the third most common method of HIV transmission. The frequency of transmission being in the deliberate and repeated use of contaminated syringes by infected persons generally occurs in users of illegal drugs. These users typically share syringes and or other improvised injecting paraphernalia. While any illegal drug can be injected, heroine and cocaine are the most widely used injectable illegal drug.
Less frequent forms of HIV transmission are vertical transmission and occupational exposure. Vertical transmission occurs when a mother, either during pregnancy, at time of delivery, or after birth (through breast-feeding) infects an infant. Occupational exposure is considered to be rare but does occur. Studies ending in 1996 found 52 documented cases and another 111 cases of possible occupational transmission. These cases, by enlarge, involved health care workers who acquired the disease after percutaneous injury, mucocutaneous exposure and exposure through open wounds. Most of these cases involve puncture wounds from needle stick type injuries.
In addition to health care workers, at risk personal include police officers, fire fighters, military personal and prison employees.
Since often the infectious contact is the result of elective human behavior, there are strategies for preventing the continued spread of HIV virus. At the center of these strategies is education which must be world wide, multileveled, intercultural and, of course, non-judgmental. Modifying behavior through education would include teaching safe sex practices, including stressing the proper and consistent use of effective condoms. Similarly for the person who continues to use injected drugs, the use sterile needles must be taught. Deactivation of HIV requires only a 30-second exposure to 100% bleach. Instruction in the cleaning methods used to deactivate HIV should be done.
Education without resources can only achieve marginal results. Therefor, although problematic and controversial it is necessary after education to provide easy and in most cases free access to condoms, sterile needles, early HIV testing and follow up medical treatment.
As discussed, while most but not all HIV transmission is the result of risky behavior, there are other causes of transmission as well. Prevention then must entail education, discipline and procedures to minimize infection through transfusion and safety procedures to prevent accidental transmission to people engaged in certain occupations such as health care workers. On this last point herein lies another controversy which is beyond the scope of this paper. That subject deals with what level should a person who is living with the HIV infection have his/her medical and or other records reflect that fact. At what point is the individual’s right to privacy negated, if ever, in regards to the individuals who are charged with caring for the infected person.
The public at large uses interchangeably the terms HIV and AIDS. This sloppy inaccuracy is one of the basis for the gross misunderstanding of the disease. HIV is divided into two categories; type I, which is found throughout the world and has resulted in most of the reported cases of infection, and type 2, which is localized to Western African coastal nations and areas outside of Africa which have commercial and cultural relations with that region. HIV infection ultimately leads to the disease of AIDS. But it is not AIDS in and of itself.
Within one to three weeks of initial exposure seroconversion occurs. This is the detectable development of HIV antibodies. While the virus is usually detectable, acutely veril and can be passed along, the infected person shows few or no symptoms. From the initial exposure period or roughly from two to six months flu like symptoms will appear in the infected person. The individual will begin to develop antibodies to fight the infection. The individual will frequently appear to be acutely ill. Well before the end of the first year the HIV infection will become asymptomatic. (It should be noted that during this period of time the disease is not dorment but is systematically destroying t-helper cells). During this phase, which will last perhaps into the eighth year of infection, the infected individual will manifest no symptoms of disease. But, nonetheless, will be infectious. Between the eighth and tenth year of infection symptoms of HIV disease will manifest.
After ten to fourteen years HIV disease advances into its terminal stage which is known as AIDS. This stage is epitomized by the body’s inability to fight any infection. Thus any infection is potentially fatal to the AIDS patient. In no way to make light of the subject, it is reminiscent of the turn of the century novel by HG Wells, “War of the Worlds”. In this first science fiction story that deals with an alien invasion of earth by undefeatable machines, human bacteria proves lethal to these unstoppable forces. Similarly, the most mundane infection is a potential lethal agent to the AIDS patient. However, some opportunistic infections are more frequently associated with AIDS patients than others. Of these opportunistic infections the most frequently encountered are those that are respiratory in nature, particularly pneumoncystic carinii pneumonia and Kaposi’s sarcoma. Interestingly, prior to the discovery of HIV/AIDS these two diseases were extremely rare and the dramatic increased occurrence of chronic ailments lead to the discovery of HIV/AIDS. While respiratory system diseases or organisms are most typical other OI can, with fatal consequences strike AIDS patients. The OI can attach any of the body’s systems including the integumentary, gastrointestinal and neurologic systems. For any of these diseases a variety of diagnostic tests are appropriate and similarly with each disease a variety of treatment regimes have been established. However, there is no cure for AIDS. This is not to say that in the early stage of the disease the OI may be successfully resolved. But in the final analysis the OI that strikes the late stage AIDS patient will at some point become fatal.
There are several drugs that are available for the treatment and management of opportunistic disease associated with AIDS. Prophylactically used these medications have contributed to the decrease morbidity associated with HIV infection. The individual must take these medications throughout their lives to attempt to control the opportunistic disease as the body’s immune system degenerates. These drugs are more effective if used in combination with each other, combination therapy has become the standard of care. These “cocktails” are more effective than single drug therapy. Since patients have become resistant to many drugs over the long periods of time they must take them, studies have shown that combinations of antiviral drugs may reverse the resistance that has taken place. However, the side effects of these medications are severe, at best.
Nucleoside Analogues: zidovudine is the drug of choice to be used initially in combination therapy. Side effects of headache and nausea usually resolve within one month. Other side effects can be more serious such as granulocytopenia, thrombocytopenia, seizures, bone marrow suppression and anemia. Some of these side effects only occur after long term use. This class of drugs inhibits replication of HIV virus by incorporating into cellular DNA thereby terminating the cellular DNA chain.
Didanosine, which is in the same classification and acts the same as zidovudine but is used in patients who cannot tolerate zidovudine. Life threatening side effects are pancreatitis, peripheral neuropathy, seizures, CAN depression, leukopenia, granulocytopenia, thrombocytopenia and anemia. Other treatable side effects are nausea and vomiting, diarrhea, abdominal pain, constipation, stomatitis, liver abnormalities, oral thrush and many more usually resolve in a month. These drugs must be taken around the clock to maintain a therapeutic blood level.
Non-nucleoside Reverse Transcriptase Inhibitors (NNRTIS) a class of drugs which binds directly to reverse transcriptase and blocks RNA, DNA conversion causing a disruption of the enzyme site. Nevirapine is used in combination therapy along with other antiviral drugs. Side effects include but are not limited to; rash, thrombocytopenia, fever, headache, nausea, hepatitis, myalgia, etc. The patient must be instructed to report any rash immediately since a rash may progress to Stevens-Johnsons syndrome, which may result in death.
Delavirdine is in the same class of drugs as nevirapine. This drug interferes with DNA synthesis that is needed for viral replication. Some side effects of the drug are; fatal metabolic encephalopathy, blood dyscrasias and acute renal failure. Common side effects are nausea and vomiting, headache, vaginitis, rash and elevated LFT’s. Again, this drug is used in combination therapy.
Protease Inhibitors, another class of drugs inhibits HIV protease, which prevents the maturation of the infectious virus. Saquinavir is generally well tolerated because of low absorption rate. This is used in combination with nucleoside analogues, NNRTIS and other protease inhibitors. Side effects are; pain, rash, diarrhea, buccal mucosa ulceration, abdominal pain, nausea, parathesia, headache and hyperglycemia. This drug should not be used in children, pregnancy, lactation and with caution in patients with liver disease.
The patients must understand that adherence to the drug regimes is extremely important since inadequate adherence can lead to drug resistance and ultimately drug failure. There is little question that early detection is essential to optimum therapeutic management. An obvious benefit of early detection would be corrective treatment of other sexually transmitted diseases, tuberculosis and immunization against the onset of OD and viruses.
Lastly, it must be recognized that often life style issues and high-risk behaviors have seriously damaged and weakened the AIDS patient’s immune system and health prior to onset of AIDS.
Therefore, along with medication life style adjustment is an intricate part of AIDS treatment. Cessation of risky behavior, abstinence from alcohol, tobacco and illegal drugs is essential aspects of the treatment program. Additionally, it is believed that an interdisciplinary approach incorporating acupuncture, massage therapy and other non traditional remedies may be useful if only in raising the mental attitude of the patient. Interestingly AIDS may be the vehicle for western medicine to entertain more seriously the various treatments of non-traditional therapies, if only to underscores the relationship between health and a positive attitude.
CONCLUSIONS
In 1985 AIDS was viewed as an immediate death sentence, and a horrific one at that, to the infected person. There was apocalyptic terror that this epidemic could wipe out mankind. Now, although there is still no cure for AIDS, education and other aggressive actions are stemming the spread of the disease. On an individual basis, the length and quality of life of people living with the AIDS virus is dramatically increasing. Medicine will ultimately conquer AIDS and with the confidence of having done so, medical practitioners will be better prepared and equipped to meet the next plague when and if it comes.