HIV and AIDS 101 - The Basics
What is HIV?
HIV stands for Human Immunodeficiency Virus. It’s similar to other viruses, such as colds and the flu, with one important difference—the human body cannot get rid of HIV. That means once a person has HIV, he or she has it for life.
HIV affects specific cells of the immune system (called CD4 cells). Over time, HIV can destroy so many of these cells that the body can’t fight off infection anymore.
What are the stages of HIV?
HIV is a progressive disease, meaning it advances or worsens over time. If a person is infected with HIV and doesn’t get treatment, it will eventually overwhelm his or her immune system and lead to acquired immune deficiency syndrome (AIDS).
The stages of HIV are:
For more information visit the Stages of HIV page.
What is AIDS?
AIDS stands for Acquired Immune Deficiency Syndrome. It is the final stage of HIV infection. People in this stage of the disease have badly damaged immune systems and are vulnerable to other infections, called opportunistic infections. These are infections that occur because of a weakened immune system. People are diagnosed with AIDS when they have one or more specific opportunistic infections, certain cancers, or a very low number of CD4 cells, which are important parts of the immune system.
People are generally diagnosed with AIDS when they have both a low CD4 count and one or more opportunistic infections.
For more information on Opportunistic Infection, please see CDC's brochures on Opportunistic Infection.
How is HIV spread?
There is no cure for HIV, but you can prevent HIV infection. HIV is transmitted from one person to another:
To reduce your risk of getting HIV
More detailed information about preventing HIV can be found in the Prevention section of this website.
Who is at risk for HIV?
Anyone can be infected with HIV. However, certain groups of people are disproportionately affected by HIV. This means that these groups have more HIV infections than other groups, even though their overall group size is small. In the United States these groups are disproportionately affected by HIV: gay/bisexual and other men who have sex with men (MSM), blacks/African Americans, and Hispanics/Latinos. Women—including those who are pregnant—also face risk. Those who abuse intravenous drugs and other substances are also at high risk.
If you think you are at high risk for exposure, or you have sex partners who may be, you should be tested for HIV at least once each year. Everyone between ages 13 and 64 should be tested at least once as part of routine health care.
Gay, Bisexual, or Other Men Who Have Sex with Men (MSM)
Other relevant statistics for MSM
To learn more about these statistics, visit CDC’s page on HIV among Gay, Bisexual and Other Men Who Have Sex with Men (MSM).
Other relevant statistics for blacks/African Americans
To learn more about these statistics, visit CDC’s page on HIV among African Americans.
Other relevant statistics for Hispanics/Latinos
To learn more about these statistics, visit CDC’s page on HIV among Hispanics/Latinos.
Women who are infected with HIV typically get it by having sex with a man who is infected or by sharing needles with an infected person.
Pregnant women who are HIV-positive can work with their health care providers to ensure their babies do not contract HIV during pregnancy, delivery, and/or after delivery (through breast milk). It is possible for a mother to have HIV and not spread it to her baby, especially if she knows about her HIV status early and works with her health care provider to reduce the risk.
Out of 50 pregnant women with HIV, the risk of them passing HIV to their babies is approximately:
Remember that HIV also can be spread through breast milk, so mothers with HIV should not breast-feed their babies.
Intravenous Drug Users (IDUs)
Can you tell if a person has HIV by looking at them?
No. Not everyone with HIV looks sick, and many people have it but don’t know they’re infected.
Is there a cure for HIV?
No. Many researchers continue to work to find a vaccine that will prevent HIV infection, as well as treatments that may one day cure HIV. There are, however, medications that can help many people infected with HIV live with the disease, stay as healthy as possible, and prolong their lives. It is important that individuals get tested for HIV, and start medical care and treatment as soon as possible to have the greatest effect.
Hasn't Magic Johnson been cured of HIV?
No. Irving “Magic” Johnson announced he was infected with HIV in 1991. Like many Americans living with HIV, Mr. Johnson takes medication each day to reduce the amount of HIV in his body. For some people, HIV medications work so well that HIV is “undetectable” in a blood test. This does not mean that they no longer have HIV; it just means that the blood test cannot detect HIV because the numbers of viruses in the blood are so low. This reduction in the amount of HIV in the body is good news and can keep people living with HIV from getting sick. But if Mr. Johnson stopped taking his medication, it is likely that he would see the levels of HIV in his body rise and his health would eventually be at risk.
Are the HIV cures I read about on the Internet real?
No. There is no cure for HIV infection. Some people have claimed to have discovered a cure for HIV and attempted to sell these cures to people living with HIV. Many of these fake “cures” can do additional physical and mental harm to people living with HIV and prevent them from seeking proven treatments and support that can extend their lives.
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Content source: Centers for Disease Control and Prevention
Page maintained by: Prevention Communication Branch, Division of HIV/AIDS Prevention
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