Skip directly to search Skip directly to A to Z list Skip directly to navigation Skip directly to page options Skip directly to site content

List of Terms

Acquired Immunodeficiency Syndrome (AIDS): The stage of HIV infection that occurs when your immune system is badly damaged and you become vulnerable to infections and infection-related cancers called opportunistic illnesses.

Antiretroviral Therapy (ART): A combination of HIV medicines that keeps the virus from growing and multiplying.

CD4 Cells (also called T-cells): The “generals” of the human immune system. These are the cells that send signals to activate a person’s immune response when they detect “intruders,” like viruses or bacteria.

CD4 Count: The number of CD4 cells in your blood.

Combination Therapy: Taking more than one HIV medicine at the same time. Combination therapy is often required for ART to be effective.

Human Immunodeficiency Virus (HIV): HIV stands for human immunodeficiency virus. It is the virus that can lead to acquired immunodeficiency syndrome, or AIDS. Unlike some other viruses, the human body cannot get rid of HIV. That means that once you have HIV, you have it for life.

Immune System: The body’s defense against infection and disease.

Opportunistic Infections: Infections that occur more frequently and are more severe in individuals with weakened immune systems, including people living with HIV.

Post-Exposure Prophylaxis (PEP): PEP stands for post-exposure prophylaxis. It involves taking antiretroviral medicines as soon as possible, but no more than 72 hours (3 days) after you may have been exposed to HIV, to try to reduce the chance of becoming HIV-positive. These medicines keep HIV from making copies of itself and spreading through your body. Two to three drugs are usually prescribed, and they must be taken for 28 days.

Pre-Exposure Prophylaxis (PrEP): PrEP stands for pre-exposure prophylaxis. The word “prophylaxis” means to prevent or control the spread of an infection or disease. The goal of PrEP is to prevent HIV infection from taking hold if you are exposed to the virus. This is done by taking one pill every day.

Sexually Transmitted Diseases (STDs): Diseases spread through sexual contact with another person. They can spread from person-to-person through contact with genital fluid or through skin-to-skin contact. Some of the most common STDs include gonorrhea, chlamydia, syphilis, trichomoniasis, human papillomavirus (HPV), genital herpes, and hepatitis A, B, and C viruses.

Undetectable Viral Load: The point at which the amount of HIV in the blood is too low to be measured by today’s methods.

Viral Load: The level of HIV in the blood.

Viral Load Test: A test that determines the amount of viral load, or HIV, in the blood.