Skip directly to local search Skip directly to A to Z list Skip directly to navigation Skip directly to site content Skip directly to page options
CDC Home

Glossary

AIDS: Acquired immunodeficiency syndrome. AIDS is a disease that causes a weak immune system. AIDS increases the risk of getting certain infections and cancers.

CD4 count: A blood test that measures the T-lymphocyte, or CD4+, count. These cells are part of your immune system. As your CD4 count goes down, your risk of developing infections goes up.

Chlamydia: A sexually transmitted disease caused by bacteria. If not treated with the appropriate antibiotics, chlamydia can lead to infertility (not being able to have a baby). It can be passed from mother to baby during birth.

CLIA-waived test: A test system, assay, or examination that has been cleared by the FDA for home use, or has been determined by the FDA to meet the CLIA criteria of being a simple test with an insignificant risk for an erroneous result.

Confidentiality: Pertains to the disclosure of personal information in a relationship of trust and with the expectation that it will not be divulged to others in ways that are inconsistent with the original disclosure. Confidentiality must be maintained for persons who are recommended and/or who receive HIV counseling, testing, and referral (CTR) services.

Confirmatory test: A highly specific test designed to confirm the results of an earlier (screening) test. For HIV testing, a Western blot, an immunofluorescence assay (IFA), or an RNA is used as a confirmatory test. The person is considered HIV-positive only if the confirmatory test result is positive.

EIA: Enzyme immunoassay, sometimes referred to as ELISA, is a commonly used screening test to detect antibodies to HIV.

False negative: A negative test result for a person who is actually infected.

False positive: A positive test result for a person who is actually not infected.

Genital herpes: A sexually transmitted disease caused by a virus. The sores associated with herpes are highly contagious. The virus can also be spread when no sores can be seen.

Gonorrhea: A sexually transmitted disease that affects the genital area and urinary tract. You can have gonorrhea without any symptoms.

Hepatitis B and Hepatitis C: Viruses that affect the liver. They spread through blood and other body fluids through unsafe sex or sharing needles and drug works. An infected mother can pass these viruses to her baby during birth.

HIV: Human immunodeficiency virus. HIV is the virus that causes AIDS. Having HIV doesn’t mean a person has AIDS.

Indeterminate test result: A possible result for a Western blot, which might represent a recent HIV infection or a false-positive.

Immune system: The body’s defense against infection and disease.

Nucleic acid amplification testing: A type of testing that identifies viral genes (e.g., specific sequences of nucleic acids) using gene amplification technologies such as polymerase chain reaction (PCR).

Preliminary positive test: For rapid HIV testing, a test result that is reactive by a rapid HIV test and not yet confirmed positive by a Western blot, IFA, or approved RNA supplemental test.

Rapid HIV test: A test to detect antibodies to HIV that can be collected and processed within a short interval of time (e.g., approximately 10 to 60 minutes).

Referral laboratory: An external laboratory to which a sample is submitted for a supplementary or confirmatory examination procedure and report.

RNA test: A test used to detect HIV-1 in plasma using nucleic acid amplification. The test may be used as a confirmatory test for a reactive rapid HIV test result to aid in the diagnosis of infection with the virus.

Screening test: An initial test, usually designed to be sensitive, to identify all persons with a given condition or infection.

Seroconversion: Initial development of detectable antibodies specific to a particular antigen; the change of a serologic test result from negative to positive as a result of antibodies induced by the introduction of antigens or microorganisms into the host.

Syphilis: A sexually transmitted disease. If left untreated, syphilis can cause heart and brain damage, paralysis, blindness, and possibly death.

Viral load: Refers to the amount of virus in the blood.

Works: Drug equipment such as needles, syringes, spoons, filters, cottons, water, swabs, and tourniquets.

Serodiscordant couples: A couple in which one partner has HIV and the other does not.

STDs: Sexually transmitted diseases that are spread by having sex. Examples are syphilis and gonorrhea.

Western blot: A laboratory test that detects specific antibodies to components of a virus. Chiefly used to confirm HIV antibodies in specimens found to be reactive using a screening test.

For more HIV/AIDS terminology visit the NIH AIDSinfo glossary of HIV/AIDS-related termsExternal Web Site Icon

 


 

Find an HIV testing site near you.

For additional HIV services, select the "More" tab.

Search location, such as: "Atlanta, GA", or "30033".

For more information on this widget, please visit www.aids.gov

Please contact hivwebmaster@cdc.gov with any comments, suggestions, or concerns.

Services








Syndicate This Content Podcast button Tell us what you think button CDC-INFO
USA.gov: The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Rd. Atlanta, GA 30333, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 - Contact CDC–INFO