HIV Infection and AIDS: An Overview

red ribbon in front of  HIV picAIDS (acquired immunodeficiency syndrome) was first reported in the United
States in 1981 and has since become a major worldwide epidemic. AIDS is caused
by HIV (human immunodeficiency virus). By killing or damaging cells of the
body’s immune system, HIV progressively destroys the body’s ability to fight
infections and certain cancers. People diagnosed with AIDS may get
life-threatening diseases called opportunistic infections, which are caused by
microbes such as viruses or bacteria that usually do not make healthy people

More than 900,000 cases of AIDS have been reported in the United States since
1981. As many as 950,000 Americans may be infected with HIV, one-quarter of whom
are unaware of their infection. The epidemic is growing most rapidly among
minority populations and is a leading killer of African-American males ages 25
to 44. According to the Centers for Disease Control and Prevention (CDC), AIDS
affects nearly seven times more African Americans and three times more Hispanics
than whites. In recent years, an increasing number of African-American women and
children are being affected by HIV/AIDS. In 2003, two-thirds of U.S. AIDS cases
in both women and children were among African-Americans.


HIV is spread most commonly by having unprotected sex with
an infected partner. The virus can enter the body through the lining of the
vagina, vulva, penis, rectum, or mouth during sex.

Risky behavior

HIV can infect anyone who practices risky behaviors such as

  • Sharing drug needles or syringes
  • Having sexual contact, including oral, with an infected person without using
    a condom
  • Having sexual contact with someone whose HIV status is unknown

Infected blood