AIDS has spread throughout the world. There seems to be two worldwide patterns in the spread of AIDS, which is not contracted by casual contact. A 1959 blood sample from central Africa contained the first known human infection. Researchers discovered that the common form of AIDS, caused by HIV-1, jumped from chimpanzees to human beings in the region of Gabon in western Africa. Homosexual men and intravenous drug users primarily spread the disease and are the groups at highest risks in parts of the country like, Australia and western Europe. In the United States in 1988; the only area in which infections are increasing is throughout heterosexual sex. It can also be transmitted from a mother to her unborn child and unprotected sex (Tamarin, 502).
HIV is a retrovirus, a unique group of RNA viruses, which was first diagnosed in 1981 among young male homosexuals in the United States. It is called a retrovirus because they contain an enzymatic activity referred to as reverse transcriptase, which synthesizes a DNA copy of an ssRNA genome. A typical retrovirus consists of an RNA genome enclosed in a protein capsid ( Mckee & Mckee, 604).
The Aids virus attacks helper T cells, a particular protein on the surface of these T cells, called CD4, is a receptor for the HIV virus coat protein, gp120 it secondary receptor, the protein CCR5, is also needed for the virus to gain entry into the cell. HIV also attacks macrophages. With destruction of the T cells, a person’s immune system loses the ability to fight off common diseases. Persons develop the disease frequently victim to opportunistic diseases. Such as Pneumonia and Kaposi’s Sarcoma, a rare cancer found in people taking immunosuppressive drugs. These conditions collectively became known as the acquired immune deficiency syndrome (Tamarin, 502).
In the reproductive cycle of the retrovirus HIV, the infective process begins when the virus binds to a host cell. Binding which occurs between viral surface glycoproteins and specific plasma membrane receptors, initiates a fusion process between host cell membrane and viral membrane. Subsequently, the viral capsid is released into the cytoplasma and the viral reverse transcriptase catalyzes the synthesis of a DNA strand that is complementary to the viral RNA. This enzymatic activity also catalyzes the conversion of the single-stranded DNA into a double stranded molecule. The double stranded DNA version of the viral genome is then translocated into the nucleus where it integrates into a host chromosome. The integrated proviral genome, acting like a prophage, is replicated each time the cell undergoes DNA synthesis. The mRNA transcripts produced when the viral genome is transcribed direct the synthesis of numerous copies of viral proteins (McKee& McKee, 604&605).
There are some techniques in AIDS prevention but the one that is most effective but rarely practiced is abstinence. Some others are listed below:
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Barrier Methods- Physical or Chemical substances, which prevent pregnancy and/or block the spread of STD’s including HIV. They do not however include hormonal contraceptive methods.
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Condoms- Safe sex
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Spermacides- Gels, creams, foams, or films that can be inserted into the vagina. One of the most widely used spermacide is Nonoxynol (N-9).
- HIV Self-Test Kit
There is no cure for AIDS. Treatment seeks to suppress symptoms (e.g., antibiotics for the infections) and slow viral reproduction. Mortality rates have decreased since 1995 because of the introduction of a treatment protocol called highly active antiretroviral therapy (HAART) that consists of combinations of drugs from the following categories: (1) nucleoside reverse transcriptase inhibitors (NRII’s) .
(2) Non- nucleoside reverse transcriptase inhibitors (NNRII’s) and protease inhibitors (e.g., indinavir). Both NRII’s and NNRII’s inhibit vDNA synthesis catalyzed by reverse transcriptase. Protease inhibitors are a class of drugs that prevent the processing of viral protein that is required for the assembly of new virions. Because the viral genome mutates frequently, developing an AIDS vaccine is problematic (McKee& Mckee, 605)!
