Since the beginning of the pandemic, nearly 80 million people have become infected with HIV and more than 36 million have died of AIDS-related illnesses.

Basic Facts About HIV

What is HIV?

What is AIDS?

HIV stands for human immunodeficiency virus. It is the virus that causes AIDS. A member of a group of viruses called retroviruses, HIV infects human cells and uses the energy and nutrients provided by those cells to grow and reproduce.

AIDS stands for acquired immunodeficiency syndrome. It is a disease in which the body’s immune system breaks down and is unable to fight off infections, known as “opportunistic infections,” and other illnesses that take advantage of a weakened immune system.

HIV/AIDS in the U.S.

Roughly one in five new HIV diagnoses in the U.S. are among young people aged 13-24.

HIV/AIDS in the World

Approximately 4,100 people worldwide become infected with HIV every day.

Snapshots of an Epidemic: An HIV/AIDS Timeline

Our chronicle of the HIV/AIDS pandemic begins in the summer of 1981, when the first cases of a mysterious and deadly new pathogen come to light.

HIV Resources

A wide range of local, national and international organizations conduct research and provide services, information and advocacy for individuals and communities affected by HIV.