What Does “AIDS” Mean?
AIDS stands for Acquired Immune Deficiency Syndrome:
Acquired means you can get infected with it.
Immune Deficiency means a weakness in the body’s system that fights diseases.
Syndrome means a group of health problems that make up a disease.
AIDS is caused by a virus called HIV, the Human Immunodeficiency Virus. If you get infected with HIV, your body will try to fight the infection. It will make “antibodies” — special molecules to fight HIV.
A blood test for HIV looks for these antibodies. If you have them in your blood, it means that you have HIV infection. People who have the HIV antibodies are called “HIV-Positive.” Fact Sheet 102 has more information on HIV testing.
Being HIV-positive, or having HIV disease, is not the same as having AIDS. Many people are HIV-positive but don’t get sick for many years. As HIV disease continues, it slowly wears down the immune system. Viruses, parasites, fungi and bacteria that usually don’t cause any problems can make you very sick if your immune system is damaged. These are called “opportunistic infections.”
How Do You Get AIDS?
You don’t actually “get” AIDS. You might get infected with HIV, and later you might develop AIDS. You can get infected with HIV from anyone who’s infected, even if they don’t look sick and even if they haven’t tested HIV-positive yet. The blood, vaginal fluid, semen, and breast milk of people infected with HIV has enough of the virus in it to infect other people. Most people get the HIV virus by:
having sex with an infected person;
sharing a needle (shooting drugs) with someone who’s infected;
being born when their mother is infected, or drinking the breast milk of an infected woman.
Getting a transfusion of infected blood used to be a way people got AIDS, but now the blood supply is screened very carefully and the risk is extremely low.
What Happens if I’m HIV Positive?
You might not know if you get infected by HIV. Within a few weeks after being infected, some people get fever, headache, sore muscles and joints, stomach ache, swollen lymph glands, or a skin rash for one or two weeks. Most people think it’s the flu. Some people have no symptoms. Fact Sheet 103 has more information on the early stage of HIV infection.
The virus will multiply in your body for a few weeks or even months before your immune system responds. During this time, you won’t test positive for HIV, but you can infect other people.
When your immune system responds, it starts to make antibodies. When this happens, you will test positive for HIV. After the first flu-like symptoms, some people with HIV stay healthy for ten years or longer. But during this time, HIV is damaging your immune system.
One way to measure the damage to your immune system is to count your CD4+ cells. These cells, also called “T-helper” cells, are an important part of the immune system. Healthy people have between 500 and 1,500 CD4 cells in a milliliter of blood. Fact Sheet 124 has more information on CD4 cells.
Without treatment, your CD4 cell count will most likely go down. You might start having signs of HIV disease like fevers, night sweats, diarrhea, or swollen lymph nodes. If you have HIV disease, these problems will last more than a few days, and probably continue for several weeks.
