It is also known as the "early HIV test" or "RNA test". This test looks for the genetic material of HIV in the blood. Ninety-nine percent of these tests will be positive 6 weeks after a person gets HIV. The 4th generation EIA test is the standard HIV laboratory screening test used in BC. This p24 antigen shows up in the blood soon after a person gets HIV. The antigen, or viral protein, used to detect HIV is called p24 antigen. The 4th generation Enzyme Immunoassay Test (EIA) test is a combined antigen / antibody test. The HIV Confirmatory Assay (Immunoblot test) is an antibody test used to confirm a preliminary positive HIV result.
The point-of-care (or rapid) HIV test is an antibody tests offered in some locations in BC. Up to 95% of people will have antibodies after 6 weeks, and 99% of people will have antibodies after 3 months.
The window period for antibody tests is between 3 weeks and 3 months. It takes time for the body to make antibodies after it is exposed to HIV, and different people make antibodies at different rates. Antibodies are proteins made by the immune system when the body is exposed to an infection. As HIV testing technology improves, window periods may become more specific or even get shorter. Different HIV tests have different window periods. Window periods are based on averages or statistics from studies.