The Human Immunodeficiency Virus (HIV) is a virus that infects the immune system. Acquired Immune Deficiency Syndrome (AIDS) is the most advanced stage of the HIV infection. HIV causes the immune system to become vulnerable to other infections. There is presently no cure or vaccine for HIV. It takes, on average, 10 years for the initial HIV infection to progress to AIDS.

The human immunodeficiency virus (HIV) can pass from one person to another in the following ways:

• by unprotected sexual intercourse with infected persons
• by using contaminated needles
• via transfusion of infected blood or blood products
• from an infected mother to her infant before or during birth
• via organ transplant from an infected donor

HIV is not found in vomit, feces, nasal secretions, tears or urine unless these fluids are visibly contaminated with blood.

HIV is not spread by casual contact. There is no risk of becoming infected with HIV by working on the same assembly line, using the same equipment, sharing locker rooms or toilet facilities or being in the same office as someone with HIV infection or AIDS.

All workers who are in contact with contaminated blood or other body fluids are at risk. Exposure to HIV in the workplace occurs through:

• skin and mucous membrane contact with blood and other body fluids of an infected person
• accidents with needles or other sharp instruments contaminated with the blood of an infected person

The Centers for Disease Control recommend using "universal precautions" to protect workers at risk from HIV exposure. This approach stresses that all situations involving contact with blood and certain other body fluids present a risk. Universal precautions outline the use of barriers to prevent workplace exposure to HIV and other viruses. These barriers include the use of:

• engineering controls such as retractable needles
• safe work practices and administrative controls
• protective equipment such as gloves, gowns or aprons, masks, and protective eye wear.