HIV Facts


HIV stands for Human Immunodeficiency Virus. It is a virus that attacks the human immune system. It is the virus that causes AIDS.


AIDS stands for Acquired Immunodeficiency Syndrome. It is the result of HIV attacking the human immune system to the point where the body cannot fight off various diseases and illnesses (called opportunistic infections) that typically don’t affect a person with a healthy immune system. AIDS is the most advanced stage of HIV and can only be diagnosed by a doctor. 

There are two ways that doctors decide when a person infected with HIV is considered to have advanced to an AIDS diagnosis:

  1. From other infections: When a person’s immune system is so weakened by HIV that s/he gets one or more opportunistic infections.
  2. From certain blood tests: Doctors can perform specific tests that measure how well the immune system is working (commonly known as a CD4 Count) and how much virus is in the body (known as a viral load test).

How quickly someone with HIV advances to AIDS depends on many different factors. One important factor is how soon after HIV infection a person is diagnosed and gets into care. Also, just like any other health problem, different people’s bodies respond differently to HIV. So, it is important to get tested, get medical care if you are positive and protect yourself and your partner(s).


HIV is spread when an HIV-infected person's body fluids (blood, semen, fluids from the vagina or breast milk) enter another person’s bloodstream.

The most common way people are infected with HIV is by having unprotected sex (vaginal, anal or oral). While having unprotected sex, the virus can enter the bloodstream through linings in the mouth, anus, sex organs (the penis and vagina), or through broken skin.

Pregnant women with HIV can give the virus to their babies during pregnancy, child birth or through breastfeeding.

HIV can also be spread by sharing needles that are used for taking drugs (legal and illegal), tattooing, and piercing. Both men and women can spread HIV. A person with HIV can feel okay and still give the virus to others.


Often, people don’t think of themselves or their partners as being at risk, so they don’t worry about using protection or getting tested. But anyone can get HIV if they engage in certain activities. You may have a higher risk of getting HIV if you:

  • Have unprotected sex. This means vaginal or anal intercourse without a condom and/or oral sex without a latex barrier with a person infected with HIV.
  • Share needles to inject drugs or steroids with an infected person; or share needles used for tattooing or body piercing.
  • Receive a blood transfusion from an infected person. This is very unlikely in the U.S. and Western Europe, where all blood is tested for HIV infection.
  • Are born to a mother with HIV infection. A baby can also get HIV from the breast milk of an infected woman.

If you fall into any of the categories above, you should consider being tested for HIV.