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P24 antigen + VIH1+2 test

Question: 

I had a risk behavior so I want to know as much as possible i can.

6-7 Days after the relation, i went to MD and he told me that i have to wait to take hiv test, but in case i couldnt i should take P24 antigen test + VIH1+2 test.

I dont know wich generation the test was, bur the results are:

VIH 1 + 2 NEGATIVE
Technic: Antingen-Antibody reaction

Ag. P 24 NEGATIVE
Technic: WESTERN-BLOT

With this information: is it possible to know wich generation of test the lab performed?
Ag.P 24 is reliable?

I understand that i have to wait to have another test. but with those a made mean something? or do not at all.

Regards

Answer: 

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, and on the accuracy of some tests you've had since then. We're happy to answer your question for you.

You likely had the DUO/COMBO test (a 4th generation test) and the RAPID test (a 3rd generation test). Here is a bit more information on these tests:

Test Name
Method
Window Period
Conditions
Rapid or “Point-of-Care” Blood or oral swab test that looks for antibodies. Up to 95% of infections are detectable within 4-6 weeks post exposure. Most people develop detectable antibodies in 21-25 days. The rapid test is a type of 3rd Generation test. Two forms available: finger prick blood sample or oral swab. Oral swab test is most common in the U.S. but due to false positives in Canada it is not approved and blood collection is more likely. Many places in the U.S. and abroad may charge a fee for rapid testing. Conclusive at 3 months post exposure.
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 both of these tests are considered conclusive, meaning their results are taken as accurate, 3 months post exposure. You've had these tests only 1 week after the encounter you're concerned about, so they have been done much too soon to be meaningful in any way. You'll have to go for further testing at 3 months to know your status conclusively.

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

Trevor

AIDS Vancouver Helpline/Online
helpline.aidsvancouver.org