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p24 Antigen

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Also known as: p24 capsid or core antigen; p24 antigen capture assay; p24 protein; HIV antigen; HIV antigen/antibody combination testing
Formal name: p24 Antigen

At a Glance

Why Get Tested?

Most often as part of a combination HIV antibody/antigen test, to screen for infection with Human immunodeficiency virus (HIV); less commonly, as an individual test to screen for HIV after a recent exposure

When to Get Tested?

As part of a combination test, at least once if you are age 13-64 years; annually if you are at increased risk for HIV; as an individual test, soon after you think you have been exposed to HIV

Sample Required?

A blood sample drawn from a vein in your arm or by a fingerstick

Test Preparation Needed?

None