The 28-Day HIV DUO test can detect the virus from 28 days after infection. It is called a "DUO" test because it combines a test for antibodies for the HIV 1 and 2 strains of the virus, with an antigen test for the p24 antigen.

How does the HIV DUO test work?

Together with an antibody test, the p24 antigen is very accurate in determining early on whether an individual has been infected with HIV. The p24 antigen is the first marker of the presence of HIV in the body. Therefore, this test can detect an infection at an earlier stage than an antibody test on its own can.

An antigen is a foreign substance that triggers the body's creation of antibodies. With an HIV infection, the p24 protein is the antigen that most commonly triggers the body's antibody response. During the first few weeks after someone becomes infected, the p24 antigen becomes detectable in their blood.

How accurate is the test?

This Better2Know HIV test is extremely accurate at 28 days and is now the test recommended by the UK's current Guidelines on HIV testing. The Better2Know test is a fourth generation test, considered 99.8% accurate at 28 days. This accuracy increases to 99.9% at 90 days, after any potential contact.

When will I receive my results?

Your Better2Know clinician will send your blood sample to our laboratory and the results are usually available the same day as the sample is received in the laboratory.