HIV test

HIV (human immunodeficiency virus) is a viral sexually transmitted infection usually caught during unprotected vaginal or anal sex with an infected sexual partner. HIV can also be transmitted through blood by sharing needles. Also, a mother can pass it on to her baby during pregnancy or in breast milk.

HIV attacks your immune system, weakening your ability to fight infections and illness. If untreated, it may lead to the development of acquired immune deficiency syndrome (AIDS).

When should you take an HIV home test?

You should take an HIV test if you are at risk of HIV infection. This may be if you have had unprotected sex or possible exposure to HIV in another way.

What does the HIV test check for?

The HIV test will look for HIV antibodies and p24 antigens in the blood. HIV antibodies are produced by the immune system when you have a HIV type 1 or type 2 infection. P24 antigen is a protein from the HIV virus, found during the initial HIV infection.

How to use an HIV home test kit

Our finger-prick HIV blood test can be taken from 4 weeks after exposure, in your own home. The test should be repeated at 12 weeks post-exposure to confirm the results. We’ll send you everything you need, including instructions and a pre-paid return envelope for your blood sample.

Are at-home HIV test kits reliable? What you should know

At-home HIV screening kits are reliable, however:

• There is a small chance of false positive or negative results
• Self-tests may not be reliable for the detection of recent infections
• Follow-up testing is required after a reactive result, especially if you think the results are not accurate
• Certain health conditions and medicines can affect results
• Oral fluid samples may be less reliable than blood samples

What is the difference between rapid and mail-in HIV home test kits?

Rapid HIV home test kits use a finger prick or oral fluid sample and provide results within minutes. Mail-in HIV home test kits use a sample of blood that is sent to a lab for testing. Results are normally available within 2 to 5 days.

Frequently asked questions about HIV tests

How accurate are HIV home test kits compared to lab-based testing?

HIV tests are not 100% accurate. Around 0.5% of people not infected will have a false positive result. False HIV-negative results are most common during the first few weeks after HIV infection. After 3 months, HIV tests are more than 99.97% accurate. Many HIV tests give a negative result to 99% of people who do not have HIV.

What is the window period for detecting HIV using a home test?

The window period is the time between exposure and when a test can detect the infection. This will depend on the type of HIV test and how the sample is collected.

• Nucleic acid lab tests can detect HIV 10 to 33 days after exposure
• Antigen/antibody blood tests can detect HIV 18 to 45 days after exposure
• Antigen/antibody rapid tests can detect HIV 18 to 90 days after exposure
• Antibody tests (rapid or self-test) can detect HIV 23 to 90 days after exposure
• HIV self-test tells you your HIV status 90 days ago

A single HIV test 4 weeks after exposure is normally enough for most people to detect an infection. Individuals with high-risk behaviour may need more frequent testing.

How long does it take to get results from a rapid HIV self-test?

Your HIV self-test results will be available within one working day of receiving your sample at the laboratory.

Can HIV home test kits detect both HIV-1 and HIV-2?

Yes. The HIV test will look for HIV antibodies produced by the immune system when you have an HIV type 1 or type 2 infection.

What should I do if my HIV test result is positive?

If your HIV diagnosis is HIV positive, the lab will conduct further tests. If you think you have recently been exposed to HIV and need post-exposure prophylaxis, visit your nearest sexual health clinic or A&E, to speak to a healthcare provider as soon as possible for HIV treatment.