Types of HIV tests differ mainly in what they look for, how soon after an exposure they can detect HIV, where they are used, and whether a reactive result needs confirmation. Symptoms or appearance cannot tell someone their HIV status.
This is general information and does not replace individual testing advice or diagnosis. Do not start or stop HIV medicine based only on an online article or a single unconfirmed result.
What are the main types of HIV tests?
- Antibody tests look for the body's response to HIV and include many self-tests.
- Antigen/antibody tests look for both antibodies and part of the virus.
- Nucleic acid tests look for genetic material from HIV and are used in selected situations.
The names can sound technical, but the practical questions are simple: when did the exposure happen, what sample is used, and when should the result be repeated or confirmed?
What is the window period?
The window period is the time after an exposure when a test may still be too early to detect HIV. It varies by test and situation. Tell the provider the date of the most recent exposure rather than choosing a repeat date from a general chart.
What does a reactive result mean?
A reactive screening or self-test result is not the final diagnosis. Arrange confirmatory testing through a health service. A non-reactive result may also need repeating if the test was taken during the window period or if a new exposure occurred.
What if the exposure was recent?
If a possible exposure happened within the last 72 hours, contact a clinic or hospital immediately to ask about HIV PEP. Do not wait for symptoms or for the window period to end before seeking urgent assessment.
Read more about HIV self-testing and the difference between HIV and AIDS.
Frequently asked questions
Which HIV test is best?
The best test depends on timing, access, and whether urgent or confirmatory testing is needed.
Can a self-test diagnose HIV?
A reactive self-test needs confirmation at a health service.
Can medicine affect the testing plan?
PrEP or PEP use can change follow-up decisions, so tell the provider what was taken and when.
Summary
Different HIV tests have different window periods and uses. The most reliable plan combines the right test, the date of exposure, and confirmation or repeat testing when needed.
