What is the mechanism by which the AIDS virus causes deficiency of immune system of the infected person?
Solution and Explanation
AIDS (Acquired Immuno Deficiency Syndrome) is caused by the Human immunodeficiency virus (HIV) via sexual or blood-blood contact. After entering the human body the HIV virus attacks and enters the macrophages. Inside the macrophages the RNA of the virus replicates with the help of enzyme reverse transcriptase and gives rise to viral DNA. Then this viral DNA incorporates into the host DNA and directs the synthesis of virus particles. At the same time HIV enters helper T-lymphocytes. It replicates and produces viral progeny there. These newly formed progeny viruses get released into the blood attacking other healthy helper T- lymphocytes in the body. As a result the number of T-lymphocytes in the body of an infected person decreases progressively thereby decreasing the immunity of a person.
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Notes on human health and disease
Concepts Used:
HIV and AIDS
What Is HIV?
HIV is a virus that attacks cells that help the body to fight infection and making a person more vulnerable to other infections and diseases. It is spread by contact with certain bodily fluids of a person with HIV. It is most commonly during the unprotected sex or when share injection or drugs equipment.
What Is AIDS?
It is the late stage of HIV infection that occurs when the body’s immune system is badly damaged because of the virus.