HIV is usually diagnosed by testing your blood or a sample of cells taken with a swab from inside your cheek for the presence of antibodies to the virus. Urine samples can also be tested for HIV antibodies, but the results are less accurate.
Unfortunately, these HIV tests aren't accurate immediately after infection because it takes time for your body to produce antibodies to the virus. Most people develop antibodies to the HIV virus within three to six months of infection.
Regardless of the type of screening test used, a positive result will require follow-up testing to establish an HIV diagnosis. If you test positive for HIV on both the initial and follow-up testing, it means you are HIV-positive. It usually takes a few days to a few weeks to get results of an HIV test, although some rapid HIV tests can produce results in about 20 minutes.
Rapid HIV testing
Several rapid tests offer highly accurate information within as little as 20 minutes. These tests look for antibodies to HIV using a sample of your blood, drawn from a vein or a finger prick, or fluids collected on a treated pad that is rubbed on your upper and lower gums. A positive reaction on a rapid test requires a confirming blood test.
Home HIV testing
Home testing involves two options:
- Mailing a blood sample to a testing center and calling in for your results
- Collecting an oral fluid sample at home and using a kit to test it yourself
Both methods ensure anonymity and offer confidential counseling and referral to follow-up testing sites if your test results are positive.
Early-detection HIV testing
Some tests can detect HIV infection earlier, before antibodies are detectable in standard HIV testing. These early-detection tests evaluate your blood for genetic material from the virus or for proteins that develop within the first few weeks after infection.
Tests that detect HIV infection before you've developed antibodies to the virus may cost more than standard HIV testing and may not be as widely available. You will also still need standard antibody testing later to confirm results because false-positives and false-negatives are possible.
Dec. 09, 2014
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