What is human immunodeficiency virus (HIV)? HIV is a virus that
attacks and gradually weakens your immune system. HIV infects
CD4+ cells, a type of white blood cell. As HIV-infected CD4+
cells are destroyed or impaired, the immune system becomes less
able to fight infection and disease. HIV infection can progress
to AIDS. What increases my risk for HIV? Most people get HIV by
having unprotected sex with someone who has HIV. Another common
way of getting the virus is by sharing needles with someone
infected with HIV when You have an increased risk of developing
HIV through sexual contact if you: - Have unprotected sex (do
not use condoms). - Have multiple sex partners. - Are a man who
has sex with - Have high-risk partner(s) (a man or woman who has
multiple sex partners or injects drugs, or a man who has sex
with men). - Have or have recently had a sexually transmitted
disease, such as People who are also at increased risk of
developing HIV - Those who inject drugs or steroids, especially
if they share needles