HIV Antibody Tests
A human immunodeficiency virus (HIV) can lead to acquired immunodeficiency syndrome (AIDS). It is a lentivirus (a member of the retrovirus family). Its symptoms can often be mixed up with those of other viral infections like influenza.
There are tests of different kinds which are available in laboratories as well as certain other home tests. Following is the information on the available tests:
Enzyme-linked immunosorbent assay (ELISA)
This is the most commonly used test to identify the HIV antibody. This is a blood test where antibodies bind to very specific antigens to form antigen-antibody complexes. The resulting enzymes change indicating the presence and the amount of the antibody in a person. A technician from a laboratory takes a blood sample in a phial from a vein using an aseptic technique (i.e., the inside of your elbow and such areas are cleaned before a sterile needle is inserted). The vial containing the blood sample is labeled and sent to a laboratory for analysis. The sample is placed under the microscope along with a control sample to indicate the change or reaction that occurs in the patient’s sample. The analysis identifies the concentration of the substance present in the blood of the patient.
Since a blood sample has to be drawn for this test it is necessary to inform the health care personnel in case of any blood pressure issues, clotting problems or any other condition you may have that could affect the process of drawing blood from your veins.
Western Blot Assay
A second-tier test method, the western blot assay for antibodies, was administered for detecting specific antibodies, or confirmatory assay for the detection of antibodies for HIV. This is the test that is done as a next step in case of positive reaction to the ELIZA test. It is a highly specific test to further evaluate a positive or borderline reaction to the ELIZA test.
Two other tests that perform the same functions as the Western blot tests but with different procedures are an indirect immunofluorescence assay and a line immunoassay.
Follow either one of the above tests; if there is a positive reaction, a second ELIZA test must be administered to confirm the results.
Precautions to heed before taking the HIV Tests
Window Period
This is the time it takes for an affected person to react to the virus by creating HIV antibodies. During this period antibodies in the blood cannot be detected by any of the tests. This period may last anywhere between 3 weeks to 6 months at the most. Therefore if you have tested negative during this time, it would be advisable to recheck after this period.
HIV testing done as early as possible will help you gain time in providing the requisite care that is needed for the symptoms of HIV.
There are certain home tests that are available over the counter. It is advisable that the results of these tests are not taken as the final word in identifying the virus; rather it is advisable to counter-check it professionally.