HIV that Causes AIDS - Essay Example

Insert HIV CAUSE AIDS AIDS is an abbreviation for Acquired Immunodeficiency Syndrome or acquired immune deficiency syndrome, which refers to the last stage of HIV infection, whereby immunity is weakened and increases the risks of infections. AIDS is caused by Human Immunodeficiency virus, HIV, which is a virus that attacks the T-cells in the bodys immune system People with HIV/AIDS frequently suffer from complex illnesses referred to as opportunistic infections. An infected person has a low count of CD4 cells, several opportunistic infections and may also be diagnosed with different types of cancers. HIV is contained in an infected persons body fluids such as Breast milk, Blood, semen and vaginal fluids and is passed from an infected person through sexual contact and blood to blood contact. The virus may also be passed from an infected mother to the child during pregnancy, delivery and breastfeeding. HIV was first discovered in Western Africa in the 1980s and currently HIV/AIDS has no cure though with medication to slow down its advancement, the infected person can live healthier and longer (Wagner, 2008) Kochs postulates are methods set to determine the relationship between the disease and the causative agent. Robert Koch summarized the postulates into four criteria as: • The disease causing agent is present in all situations of the disease. • The pathogen can be isolated and kept in a pure culture • The pathogen should cause infection even in a different culture. • The pathogen should be retrievable from the vaccinated and similarity to the original shown. According to Robert Koch, a pathogen that caused a disease had to fulfil the postulates though currently, it has been accepted that certain species cause disease despite the fact that they do not conform to the postulate standards (Cohen, 1994) The pathogen is present in all the situations of the disease HIV fulfils Koch postulates to be the direct cause of AIDS. Several studies have shown that HIV or HIV antibodies are present in the larger percentage of the infected people around the world. The virus is found in every infected person. The major types of situations whereby HIV is present all the AIDS situations are: high prevalence of the virus or HIV antibodies among the vulnerable groups for AIDS. The vulnerable groups include gay men, contaminated blood transfusion recipients, intravenous drug users and haemophiliac. Studies of groups of male homosexuals and intravenous drug users have shown that, only the gay men and intravenous drug users who had the HIV developed immunodeficiency and AIDS despite their behaviour being similar in the groups. Also, according to the Multicentre AIDS Cohort study, which monitored 2,713 gay and bisexual men who were HIV positive for their health, it showed that only one man had a low count of CD4 cells, but he was under a cancer therapy done to weaken his immunity. Immune deficiency is not present in those who test HIV negative despite being blood, donors, blood transfusion recipients and injected drug users. Recent Group studies of haemophiliacs show the link between HIV infection and death rate. The studies show an increase in mortality among those with HIV compared to those without the virus despite the degree of haemophilia. Screening has completely eliminated AIDS from haemophiliacs and blood Transfusion recipients. AIDS defining conditions in HIV negative people show that Immune deficiency can be developed in man through other ways other than Inducement. Low immunity could be due to hereditary disorders and certain drugs (Cohen, 1994) Third and fourth postulate According to Koch, the pathogen must be isolated from the materials that are causing the disease for proper testing of his third and fourth postulates. Numerous HIV isolates have been done for HIV positive patients and a larger percentage of the HIV negative, and the virus grown in laboratory models, vitro. The isolations have been made from blood plasma, seminal fluids, amniotic fluids, brain, breast milk, cerebrospinal fluid, saliva, urine, blood cells and bone marrow. Studies of electron microscopic images show particles with the same size, structure, proteins, density, behaviour and shape as the retroviruses. HIV genomes collected from around the world are kept in the Los Alamos database, each with the same genes. Genetic similarities and differences have been used to determine the family tree of the HIV groups, types, subtypes and the hybrids known as recombinant forms. Individuals exposed to a particular similar source have genetically similar HIV strains and anyone with the HIV genetic material also has the HIV antibodies. With reference to the successful isolations and culture of HIV, it is true that HIV causes AIDS. The pathogen should cause infection even in a different culture. The postulate states that exposing or infecting an animal should cause the same disease. Experimental transmission to HIV negative humans beats logic, making the verification difficult making the postulate a controversy with respect to HIV and AIDS but accidental examples show that the postulate is valid. A laboratory accident led to the infection of three laboratory workers who were working with the same strain of HIV, and are now being monitored for clinical disease. The workers were not exposed to the other risk factors for AIDS; homosexuality, intravenous drug use and transfusion recipients. Also in another tragedy, a Florida dentist transmitted HIV to six patients. Kimberly Bergalis claimed to have no risk factors and believed her infection came from her profession. Analysed results of HIV isolated from the dentist and patients supported the dental transmission. Five of the patients did not have HIV risk factors other than the visits to the dentist for the dental procedures. The dentist and three of the patients have since died from AIDS, and one has developed AIDS. In another situation HIV-2 caused AIDS in baboons. The HIV-2 is less pathogenic in humans and its cases have been reported in Western Africa and India. HIV-2 replicates and forms persistent viraemia when introduced into yellow baboons. A recent report showed that three of five baboons infected with HIV-2 had a low CD4 cell count and a pathology similar to AIDS. These observations show the transmissibility of AIDS by human HIV strain to an animal model. In the journal of virology, it is shown that a chimpanzee infected with HIV ten years earlier also developed AIDS defining opportunistic infection. Before the opportunistic infection developed the HIV RNA viral load increased, and the CD4 cell count of the Chimpanzee also decreased. Different cultures from the chimpanzee tested positive for HIV, showing recoverability of the organism. A second healthy chimpanzee was infected with the blood and later, the HIV viral load increased, and the CD4 cell count decreased. The simian immunodeficiency virus also caused AIDS in monkeys. Reports also show that Simian Immunodeficiency virus strains when developed in a different culture and transferred as a tissue culture cause AIDS (Novembre, 1997) The Simian Immunodeficiency virus was discovered to cause an immunological reaction across Asian macaques in USA primate centres in 1985. Simian Immunodeficiency virus recovered from several primate species have been classified in terms of prevalence, pathogenesis and the genome sequence analysis. The Simian Immunodeficiency virus is closely similar to HIV with the same ten functional genes and a high DNA sequence similarity. Studies of HIV and Simian Immunodeficiency virus group have shown that Human immunodeficiency viruses are products of a Simian virus ancestor. These reports proved that the postulate of the pathogen causing infection in a different culture is valid. The Koch postulates establish the connectivity between Human immunodeficiency syndrome and the Acquired immunodeficiency syndrome. Its also widely accepted by scientists that the HIV and AIDS fulfil the Koch postulates. Based on the available evidence, we should stop arguments on whether HIV causes AIDS and focus on finding a cure for AIDS. Works cited Cohen, J. "Fulfilling Kochs postulates." Science 266.5191 (1994): 1647-1647. Novembre, F.J. and others. Development of AIDS in a chimpanzee infected with human immunodeficiency virus type 1. Journal of Virology 71(5): 4086-4102. May 1997. Wagner, Viqi. AIDS. Farmington Hills, MI: Greenhaven Press, 2008. Print. Read More