Essay Hiv-Aids

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HIV/AIDS

Inhoud
What is HIV/AIDS and how does it work?3
How can HIV/AIDS be treated?4
Natural immunity for HIV4

What is HIV/AIDS and how does it work?
HIV is a chronic, potentially fatal disease, caused by the Human Immunodeficiency Virus(HIV). HIV is a sexually transmitted infection. It can also be spread by breastfeeding, blood on blood contact with someone who is already infected and childbirth. When a fetus is in his placenta, it cannot get infected. However, when giving birth to a child, the mother’s blood gets to infect the blood of the baby. One can carry this virus without having any symptoms or becoming ill. This means that one who has HIV doesn’t immediately have AIDS. If the virus is left undiagnosed and/or untreated it can attack the human immune system. if this happens HIV progresses to AIDS. [1][2] HIV is a retrovirus. Human genes are primarily encoded by DNA. The genes of a retrovirus are encoded by RNA instead of DNA. A normal virus contains DNA, which means it can clone its self. The DNA replicates by using enzymes of the host cell. This way the virus can replicate thousands of its self. The virus molecules leave the host cell and infect other cells. [3] Unlike normal viruses, HIV only contains RNA. Therefore, retroviruses cannot replicate themselves like normal viruses do. HIV always fuses with T-cells. These cells are a group of white blood cells known as lymphocytes. For a HIV-cell to fuse with the cell, it requires the presence of certain receptors on the cell surface. In this case, CD4 - receptors and co-receptors such as CCR5 or CXCR4. When the cell fuses with the T-cell, it releases two RNA-strands and 3 different replication enzymes. Integrase, protease and reverse transcriptase. Reverse transcriptase begins the reverse transcription of the viral RNA-strands. In this process, one RNA-strand is transcribed to a RNA-DNA double helix. Now the integrase cuts the 3’ at each end of the DNA. This causes the DNA to remain two...
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