What is HIV infection?

HIV infection is a communicable disease caused by the human immunodeficiency virus (HIV) which damages the body’s immune system, the system that fights infections. Without the immune system’s protection, the body is defenseless against serious and potentially life-threatening diseases which can lead to the development of Acquired Immune Deficiency Syndrome (AIDS), the later stage of HIV infection. However, not everyone who has HIV progresses to AIDS. With proper treatment, you can keep the level of HIV virus in your body low. It involves taking a combination of HIV medicines every day. These HIV medicines can control the virus so that you can live a longer, healthier life and reduce the risk of transmitting HIV to others. Today, a person who is diagnosed with HIV and treated before the disease is far advanced can have a nearly normal life expectancy.

In the United States, HIV is spread mainly by having sex or sharing injection drug equipment such as needles with someone who has HIV.

Only certain fluids—blood, semen (cum), pre-seminal fluid (pre-cum), rectal fluids, vaginal fluids, and breast milk—from an HIV-infected person can transmit HIV. These fluids must come in contact with a mucous membrane or damaged tissue or be directly injected into the bloodstream (from a needle or syringe) for transmission to possibly occur. Mucous membranes can be found inside the rectum, the vagina, the opening of the penis, and the mouth.

HIV does not survive long outside the human body (such as on surfaces), and it cannot reproduce.

HIV is not spread by:

  • Air or water.

  • Insects, including mosquitoes or ticks.

  • Saliva, tears, or sweat. There is no documented case of HIV being transmitted by spitting.

  • Casual contact like shaking hands or sharing dishes.

  • Closed-mouth or “social” kissing

  • Toilet seats.


Today, more tools than ever are available to prevent HIV. In addition to limiting your number of sexual partners, never sharing needles, and using condoms correctly and consistently, you may be able to take advantage of newer biomedical options such as pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis.

To learn more:


HIV Transmission

HIV Prevention

HIV Testing

Basic HIV/AIDS Statistics

Basic Information on PEP

Basic Information on PrEP