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HIV test

Infection and immunity tests · also printed as HIV 1/2 Ag/Ab, HIV antigen/antibody, HIV Ag/Ab, HIV 1 and 2 antibodies, HIV combo

Typical UK adult rangeExpected result: Negative

Negative is the expected result. A test within the window period (up to 45 days) is repeated.

What this test measures

The standard HIV test looks for both the virus's p24 antigen and antibodies against HIV-1 and HIV-2. It picks up infection from about four weeks after exposure.

Why doctors request it

Offered routinely in sexual health, pregnancy, some hospital admissions and before some treatments, and available as a self-test.

What commonly pushes it up

HIV infection
Very rarely, a false positive on screening, which is why every positive is confirmed with a second test

What commonly pushes it down

A negative result is the usual finding

Everyday reasons for a value outside the range

Results can be equivocal and are then repeated
Recent vaccination or infection elsewhere can occasionally give a weak positive

About the sample

No fasting needed.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.

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This is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.