What is AIDS & HIV?".

What is AIDS & HIV?".
AIDS (acquired immune deficiency syndrome) is a condition caused by HIV. This virus attacks the immune system, the body's "security force" that fights off infections. When the immune system breaks down, you lose this protection and can develop many serious, often deadly infections and cancers. These are called "opportunistic infections" (OIs) because they take advantage of the body's weakened defenses.

In the U.S., the Centers for Disease Control (CDC) is responsible for collecting data on the number of people with AIDS. This is not the same thing as the number of people living with HIV. Remember, AIDS includes the words "immune deficiency". Since people can live with HIV an average of 10 years—without effective treatment—before their immune systems become seriously impaired, AIDS is really just an advanced stage of an HIV infection.

The CDC uses specific criteria for determining when a person living with HIV progresses to AIDS. One thing they look at is CD4 cell counts: if a person's CD4 count falls below 200, then they have officially progressed to AIDS. Another thing they look for are OIs: if an HIV-positive individual is diagnosed with an opportunistic infection that's included on the CDC's list of over two dozen possible HIV-related OIs, then they are diagnosed with AIDS.

Many OIs can be prevented and/or treated. In fact, a lot of the AIDS research you hear about has been done to find treatments or cures for specific OIs, and not just looking for drugs to stop HIV.