Question
How reliable is the DUO HIV test?
29 May 2007. Related: All topics, HIV testing, HIV transmission.
Answer
The DUO test is an HIV test that looks for antibodies for HIV-1 and HIV-2 and also looks for evidence of the p24 protein which is on the surface of the HIV particle.
The advantage of testing for p24 is that this indicator of HIV infection can be detected earlier than with tests that only looked for HIV antibodies. Four weeks after exposure, the test is likely to detect 95% of actual infections. The other 5% would show positive within three months of infection.
A medical review of this accuracy of this test is included here.
This study reports that the test was 100% accurate if you get a negative result, and 94% accurate if you get a positive result. As with other types of HIV tests, a positive result need to be confirmed with a different test.
A negative result would only need to be confirmed with a second test if you were exposed less than three months ago. As with all antibody tests, the results relate to your HIV status three months before the test.
A case report of the DUO test taking more than 4 week to generate a positive result, emphasises the importance of confirming a negative result from any test used less than three months after the exposure risk, with a follow up test 3 months later.
The DUO test has no particluar advantages over other routine test when infection is unlikely to have been recent, because p24 is only detected for a short time after infection, and before HIV antibodies can be detected.
It is very difficult to get chlamydia from receiving oral sex. If you are giving oral sex then it is possible to get chlamydia of the throat. if you were wearing a condom then you would not have got chlamydia this way. It is possible for chlamydia to remain asymptomatic and you don’t know you have it for many years. If you did a HIV test and it was negative you do not have HIV. You should not have unprotected sex with your girlfriend until your chlamydia is cleared. Asymptomatic chlamydia in women can make them infertile if not treated.
I caught chlamydia from oral sex even though I wore a condom am I at risk of HIV? I then had a HIV duo test which was negative after twenty eight days. Do I require a second test and should I have sex with my partner? Could I have got chlamydia from oral sex? Could I have chlamydia for three years and not know?
Please see a full answer to this question by following this link.
I had an exposure I think last week. I have been told I can have a RNA test after 7 days? However this test is very expensive. My question is can I do 2 x p24 tests one at 2 weeks and one at say 4 weeks will that give me a good indication?
No, the test would not have missed it three times or at these time periods. The white patch on your tongue is not HIV-related and you should see your doctor about it.
I was involved is a dangerous act with a high risk person-I did a duo at 23 days post and after 3 months-I also tested after 8 months using a duo but have tested negative. My worry is that I have a white patch on my toungue. Could the tests be missing it?
In most cases DUO tests are accurate 4 weeks after infection, althought recommendations still say to confirm after 3 months.
8 weeks is likely to be fine with a negative result.
Is a DUO negative reliable at 8.5 weeks?
Just making statements like this is not very helpful. If you’d like to include links to the research, then of course I’ll look at these.
A general guide to sensitivity of p-24 tests, including from the manufacturers, is that they may detect HIV infection 1-2 weeks earlier than an HIV antibody test.
For most people this will be several weeks after infection, and the guide for this to be useful for population testing is estimated at 4 weeks after infection. p24 tests are not sensitive for negative results to mean anything earlier than this.
A useful overview of the p24 test, from HIV inSite is at this link
Your information is very wrong the P24 test is reliable with in one week of being exposed, this information has been validated with several HIV sources. You need to change your posting. Thank you.