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4generation chemiluminescence lab test for vih 1 & 2 antigen p24 help


hi, I need help. 9 weeks ago I had a relationship risk on bleeding during sex. At 63 days (9 weeks) I do an HIV test 1 & 2 (antibody and p24antigen) by chemiluminescence fourth generation by extraction of blood of my vein. It is my result conclusive? This is better than a elisa or is the same?


Hi there, and thanks a lot for contacting the AIDS Vancouver Helpline for your HIV/AIDS related health information. It seems you're concerned about the possibility of HIV transmitting during an encounter. We're happy to answer your question for you.

If we had more details about your exposure we could perhaps provide a more accurate risk estimate, but we encourage you to check out our risk assessment page to get a better idea of the risks involved in your situation.

Here is a bit more information about the test you've had:

Test Name
Window Period
4th Generation EIA Blood test that looks for antibodies AND p24 protein antigens. Commonly referred to as the "combination," "combo" or "DUO" test. P24 protein is detectable immediately after infection but only for the first few weeks. The antibody (ab) test has a window period of 4-12 weeks post exposure. This test is widely available in North America. Most HIV specialists consider this test to be conclusive at 6 weeks but official HIV testing guidelines still recommend re-testing at 12 weeks for conclusive results. Conclusive at 3 months post exposure.

You'll see in the chart that this test is considered conclusive, meaning the results are taken as accurate, at 12 weeks (3 months) post exposure. You've had the test done at 9 weeks, so while it is a really good indicator of your present status the results were not conclusive. You'll need to go for confirmatory testing at 12 weeks post exposure to know your present status conclusively. In terms of window periods, there is no difference in Canadian guidelines between the ELISA (3rd generation) and the 4th generation test, so you'd need to wait at least 12 weeks for both tests.

Thanks a lot for contacting the AIDS Vancouver Helpline with your question, we hope it has been answered fully.


AIDS Vancouver Helpline/Online