- HIV AIDS Myths and Facts Slideshow Pictures
- Take the HIV/AIDS Quiz
- AIDS Retrospective Slideshow Pictures
- Find a local Doctor in your town
- HIV (human immunodeficiency virus) testing facts
- What is the human immunodeficiency virus (HIV)?
- What are the different types of HIV testing?
- How long does it take to get results back from an HIV test?
- Is counseling offered with HIV testing?
- How accurate is an HIV test? What is the window period for an HIV test?
- Is HIV testing necessary for pregnant women?
- Where can people find free HIV testing locations?
- Where can people find more information about HIV testing?
Quick GuideHIV AIDS Facts: Symptoms and Treatments
What is the human immunodeficiency virus (HIV)?
HIV is short for human immunodeficiency virus. This is the virus that causes the acquired immunodeficiency syndrome or AIDS. HIV is a complicated virus. It reproduces primarily in specialized cells of the body's immune system called CD4 lymphocytes. During HIV replication, the CD4 cells are destroyed. As more and more cells are killed, the body loses the ability to fight many infections. If the number of CD4 cells in the bloodstream falls below 200 per cubic millimeter, or if some other special health conditions occur, the person is defined as having AIDS. These special health conditions include infections and cancers that take advantage of the suppressed immune system. Regardless of the CD4 count, people with HIV infection carry the virus and can spread it to others through unprotected sex or contact with blood or some other body fluids.
Undiagnosed HIV infection is responsible for continued transmission, even in up to one-third of transmissions in the U.S. Of 1.2 million estimated cases in individuals over 13 years of age as of December 2012 (U.S. Centers for Disease Control and Prevention [CDC] estimates). Thus, an HIV test is important to diagnose those who are newly infected, to identify previously unrecognized infections, and to relieve the minds of those who are not infected. HIV testing is also used to reduce the risk of transmission during pregnancy, blood transfusions, and tissue transplantation.
The CDC recommends a routine HIV test for adolescent and adult patients aged 13 to 64 in all health care settings, of all women during pregnancy, and the newborns of HIV-positive women. Thus, HIV testing is considered part of routine medical practice, similar to tests that screen for other diseases. In 2006, the CDC recommended eliminating written HIV-specific consent for testing in health care facilities in order to reduce unwarranted stigma and encourage screening. HIV test consent is included with general medical consent forms, and patients are informed that HIV testing will be performed as routine unless they decline (opt-out screening). As of January 2015, all states but Nebraska had adopted routine opt-out HIV testing.
People who are at high risk for acquiring HIV should be tested at least annually. Sometimes, health care professionals request or require testing as part of evaluation and treatment for other conditions, such as women undergoing treatment with assisted reproductive technologies for infertility or treatment of viral hepatitis. There is increasing concern that not enough people are being tested. Events such as National HIV Testing Day have been used to raise awareness and increase participation in testing.
In some cases, HIV testing may be required by law. This occurs for blood that is used for transfusions, organ donors, and military personnel. States may select additional populations for mandatory testing, such as prisoners or newborns.