By Mary Kay Radnich, Tests.com Contributing Writer
Human immunodeficiency virus (HIV) is the virus that causes acquired immune-deficiency syndrome (AIDS) in people. HIV directly attacks the immune system by destroying T-cells, a type of white blood cell that the body needs to fight disease. As T-cells are destroyed, it becomes more difficult for the body to fight off infection. A person is considered to have AIDS when certain diseases or cancers are present or they present a very low T-cell count.
Anyone who falls into a high risk category for HIV/AIDS should be tested. This includes people who have shared syringes and injection paraphernalia with others, anyone who has had unprotected anal, vaginal or oral sex with men who have had sex with other men, and those having sex with anonymous or multiple partners. Those who have exchanged sex for drugs or money, or who have a diagnosis of tuberculosis or hepatitis are also at risk for HIV infection. Anyone having a blood transfusion between the years of 1978 to 1985 is at risk, as is anyone who has had sexual intercourse with anyone participating in the above behaviors.
Types of HIV/AIDS Tests
The most common type of test to diagnose HIV is a blood test that is based on the presence of antibodies in the blood stream, which the body produces in response to the HIV infection. This screening test is known as the enzyme immunoassay, or EIA. The EIA can also be used on other body fluids such as urine or oral fluid. This test is also known as the ELISA – the enzyme-linked immunosorbent assay test.
In the case of oral fluid tests, oral fluid such as oral mucosal transudate (OMT) which contains more antibodies than saliva is collected from the cheek or gums using a specialized collection device. The fluid is then subjected to an EIA antibody test to determine results.
In the case of oral fluid tests, oral fluid (but not saliva) is collected using a specialized collection device. The fluid is then subjected to an EIA antibody test to determine results.
Urine may also be collected and subjected to a similar EIA antibody test. The urine test for HIV is not as accurate as the blood or oral fluid test.
There is a rapid test which can be performed on either blood or oral fluids. This EIA type of test gives results in about 20 minutes.
A home test system, the Home Access HIV-1 Test System, has been developed. This collection system provides the patient with the ability to obtain the blood sample privately and then mail it to the medical lab. A reference number providing anonymity is provided with the kit, along with a telephone number, so that the patient can call for counseling anytime during the process as well as for obtaining the test results. This is the only home test that has received FDA approval. Kits range in price from $45 to $60.
There is a type of RNA testing for HIV that directly finds genetic material from the virus. This testing is used to check the blood supply for infected blood as well as being capable of finding HIV genetic material in the bloodstream even before antibodies are produced.
All reactive screening tests must be confirmed with a follow up test.
How HIV/AIDS Tests Work
Typically a patient who is at risk for HIV/AIDS locates a testing site (check out Tests.com’s HIV/AIDS Test Directory for more), where, blood or other body fluid will be taken from the patient and processed through a medical laboratory. The patient is then contacted with the results. If a rapid test is used, the results are available in about 20 minutes.
If a home collection kit is used, the patient will use the enclosed lancet to prick a finger, and place the blood sample on a card which is then mailed to the lab. Results are then obtained via telephone.
There are no special risks inherent with the HIV/AIDS tests, as long as proper infection control procedures are followed by the health care provider administering the test.
HIV/AIDS Test Results
An HIV test is considered to be positive when the presence of HIV antibodies is confirmed or, in the case of the RNA test, the presence of the virus’ genetic material is confirmed.
Test results from the Home Access HIV-1 Test System which is mailed to the lab are available about 7 days after the test is mailed. The results of HIV testing from your health care provider are usually available one to two weeks after the test is taken. Be sure to follow up with your health care provider if you have not received a reply within this time period.
All initial HIV/AIDS tests showing a positive result are subject to a follow up test for confirmation.