HIV is a virus that kills or damages cells of the body's immune system. AIDS stands for acquired immunodeficiency syndrome. It is the most advanced stage of HIV infection.
HIV is usually spread through unprotected sex with an infected person. AIDS may also spread by sharing needles or through contact with the blood of an infected person. Women can give it to their babies during pregnancy or childbirth.
The first signs of HIV infection may be swollen glands and flu symptoms. Severe symptoms may not appear until months or years later.
With a blood test it can be determined if a person has HIV infection.