HIV stands for human immunodeficiency virus. It harms your immune system by destroying the white blood cells that fight infection. This puts you at risk for serious infections and certain cancers. AIDS stands for acquired immunodeficiency syndrome. It is the final stage of infection with HIV. Not everyone with HIV develops AIDS.
HIV most often spreads through unprotected sex with an infected person. It may also spread by sharing drug 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-like symptoms. These may come and go within two to four weeks. Severe symptoms may not appear until months or years later.
A blood test can tell if you have HIV infection. Your health care provider can do the test, or you can use a home testing kit. Or to find free testing sites, call the national referral hotline at 1-800-CDC-INFO (1-800-232-4636 in English and en español; 1-888-232-6348 - TTY).
Strategies to reduce the risk of HIV infection include not having sex, limiting your number of sexual partners, never sharing needles, and using condoms the right way every time you have sex. People who are at high risk may take HIV prevention medicines.