HIV is one of the most common immune-suppressing diseases affecting many people across all different countries. As an immunodeficiency virus, HIV can have delayed symptoms and reveal itself in later stages where it leads to rapid deterioration of health and sudden death.
It is advisable to frequently test for HIV to detect the virus as early as possible. Early detection can help in management and control, preventing the severe symptoms and ailments associated with AIDS, the latter stage manifestation of the infection.
There are three main HIV tests available, and while all of them can be used to detect the virus, each is specifically designed to detect a given type or stage of infection.
It is important to note that tests can be falsely positive or negative. They can also be impossible to interpret (intermediary).
For such reasons, it is advisable to test from time to time. Those between 14 to 65 years old and sexually active fall within the high-risk group and should get tested at least once per year.
What Are The HIV Tests Available?
There are three main tests used to detect HIV infection. These include Antibody tests, RNA tests, and Combination tests.
1. HIV Antibody Tests
HIV antibody screening is the most popular test offered in most clinics, hospitals and mobile testing vans. The body produces specific type antigens when attacked by the HIV. The presence of more of these antigens can suggest infection.
HIV antibody testing can be done in a laboratory or using a rapid test. The latter is more popular in clinics and mobile vans as it produces results within 30 minutes or less.
Such HIV tests are conducted using blood and oral fluid (not saliva). While oral fluids can be used in the test, they often contain fewer antibodies than blood. They usually use an enzyme-linked assay known as EIA or ELISA.
Antibody tests may reveal falsely negative tests, especially when conducted during the window period before the body has produced antibodies to counter the infection.
Rapid testing kits are available for testing centers and care facilities. Those who have had antibody tests should get retested a few months later or consider a follow-up testing using antibody differentiation.
2. RNA Testing
HIV has an RNA that is different from that found in the human body and tests have been developed to detect this kind of HIV RNA.
PCR (polymerase chain reaction) test detects HIV RNA. It is often used in the IQ screening of newborns to identify if maternal antibody from positive mothers crossed the placenta into the child.
RNA HIV tests are favorable within four weeks of suspected infection before the antibodies develop. Nonetheless, RNA testing is quite expensive and is never routinely used to test for infection in most public places.
However, they are quite effective as they detect HIV directly and can show infections that are only ten days old when the virus appears in the blood stream. Although they are costly, your doctor may order one as follow up if the antibody test was positive.
3. Combination HIV Tests
Combination tests mainly involve the detection of specific antibodies and protein materials that have an association with HIV.
Most such tests are designed to detect antibodies produced to counter HIV-1 and HIV-2. They also identify a unique protein called p24. This protein forms a large part of HIV core.
Combination HIV tests are very effective as they can detect the virus within one week of infection. Antibodies can take several weeks to form even with the virus present in the blood.
A combination test can detect the p24 protein and uses a chemiluminescence reaction that emits light registered on a detector following detection of either antibody or p24.
Although there are several recommended combination tests, only one (Architect-HIV-Ag/Ab-Combo-Assay) has been approved. If the tests are positive, your doctor will recommend a repeat of the procedure to confirm infection.
There are other tests available including the use of home kits, and while these may be convenient for some people, they are not always recommended as some people have had false negative results with such methods. However, they do offer privacy and usually a toll-free number to call with questions or for counseling. Use it as a starting point, then if needed get tested again.
Some will suggest to test for HIV in professional medical facilities such as doctor’s office, clinic, mobile testing van and scheduled testing tents.
This is because professional doctors can recommend other tests to clarify any issues and help you get an accurate result as well as advice on how to handle and deal with either positive or negative result.