“HIV” stands for Human Immunodeficiency Virus. To understand what that means, let’s break it down:
HIV is a lot like other viruses, including those that cause the "flu" or the common cold. But there is an important difference – over time, your immune system can clear most viruses out of your body. That isn't the case with HIV – the human immune system can't seem to get rid of it. That means that once you have HIV, you have it for life.
We know that HIV can hide for long periods of time in the cells of your body and that it attacks a key part of your immune system – your T-cells or CD4 cells. Your body has to have these cells to fight infections and disease, but HIV invades them, uses them to make more copies of itself, and then destroys them.
Over time, HIV can destroy so many of your CD4 cells that your body can't fight infections and diseases anymore. When that happens, HIV infection can lead to AIDS, the final stage of HIV infection.
However, not everyone who has HIV progresses to AIDS. With proper treatment, called “antiretroviral therapy” (ART), you can keep the level of HIV virus in your body low. ART is the use of HIV medicines to fight HIV infection. It involves taking a combination of HIV medicines every day. These HIV medicines can control the virus so that you can live a longer, healthier life and reduce the risk of transmitting HIV to others. Before the introduction of ART in the mid-1990s, people with HIV could progress to AIDS in just a few years. Today, a person who is diagnosed with HIV and treated before the disease is far advanced can have a nearly normal life expectancy.
No safe and effective cure for HIV currently exists, but scientists are working hard to find one, and remain hopeful.
“AIDS” stands for Acquired Immunodeficiency Syndrome. To understand what that means, let’s break it down: A – Acquired – AIDS is not something you inherit from your parents. You acquire AIDS after birth. I – Immuno – Your body's immune system includes all the organs and cells that work to fight off infection or disease. D – Deficiency – You get AIDS when your immune system is "deficient," or isn't working the way it should. S – Syndrome – A syndrome is a collection of symptoms and signs of disease. AIDS is a syndrome, rather than a single disease, because it is a complex illness with a wide range of complications and symptoms. As noted above, AIDS is the final stage of HIV infection, and not everyone who has HIV advances to this stage. People at this stage of HIV disease have badly damaged immune systems, which put them at risk for opportunistic infections (OIs). You are considered to have progressed to AIDS if you have one or more specific OIs, certain cancers, or a very low number of CD4 cells. If you have AIDS, you will need medical intervention and treatment to prevent death. For more information, see CDC’s HIV/AIDS Basics.