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What is HIV?

What is HIV?

HIV stands for the human immunodeficiency virus:

H - Human. This virus infects human beings.

I - Immunodeficiency. This virus attacks a person's immune system. The immune system is the body's defense against infections, such as bacteria and viruses. Once attacked by HIV, the immune system becomes deficient and doesn't work properly.

V - Virus. A virus is a type of germ too small to be seen even with a microscope.

HIV is a virus. Some viruses, such as the ones that cause colds or flu, stay in the body for only a few days. HIV, however, never goes away. A person who is infected with HIV is said to be "HIV positive." Once a person is HIV positive, that person will always be HIV positive.

What does the virus do?

All viruses must infect living cells to reproduce. HIV takes over certain immune system cells that are supposed to defend the body. These cells are called CD4 cells, or T cells.

When HIV takes over a CD4 cell, it turns the cell into a virus factory. It forces the cell to produce thousands of copies of the virus. These copies infect other CD4 cells. Infected cells don't work well and die early. Over time, the loss of CD4 cells weakens the immune system, making it harder for the body to stay healthy.

Pop question: True or false: CD4 cells are the cells in the body that fight HIV.

Answer: TRUE. CD4 cells are the cells in the body that fight HIV. They are part of the body's immune system.