Thank you for the answer, Canadiangirl. I've rrad conflicting infor on it. If p24 peaks at say 16 days, is the portion of the duo test less accurate from say day 17 on as antibodies are producing and p24 isnt as "strong"? Is this that "second window" I've read about? Or is that old information?
I've seen all over that DUO can be used and effective (with follow up of course) but as a good indication as early as 10 days. I would say once your in the 14-16 day range anywhere in there looks to be pretty accurate to detect for the antigen.
If a duo is almost 100% conclusive at 28 days, and p24 is detectable on a duo as early as 14 days. Are there percentages for when p24 is detectable via a duo at say 14 days / 17 days / 21 day?
All hiv Tests are conclusive at 13 weeks (USA). Canada 12 weeks or 84 days. 6 months is no longer used.
4th generation is conclusive after 28 days, as the P24 antigens are at their peak and stay detectable for a further 2 months. The P24 protein is not affected by the immune system, compared to the antibodies which Vary slightly in response from each individual
If a person's P24 antigen cannot be detected at 3 to 4 weeks, it does NOT mean that that person is conclusively negative.
If a person's antibodies cannot be detected at 3 to 4 weeks, it TOO does NOT mean that that person is conclusively negative either.
That is what the 4th gen is supposed to do. It detects antibodies and antigens at 4 weeks, therefore, at 4 weeks it is flawed as a "stand-alone" diagnostic test.
The 4th gen at 4 weeks is an excellent indication. BUT NOT CONCLUSIVE.
Wait for 28 days or after (4-6 weeks) and test with 4th generation Duo, at this point P24 antigen will be at peak and antibodies will also be be forming. This is conclusive unless you have immune disorder or on chemo/PEP! This 3 month and 6 month is commercial
Well most people don't have HIV. Your doing the right thing by testing. You should turn out ok. There has been people on here that report full blown ARS symptoms (fever, diarrhea, rash, fatigue) following an exposure they were concerned about and turned out fine.
Your welcome. Glad to help.
Yes the Duo is accurate at 14 days since at that time the p24 antigen is detectable by the test. That's why they call it Duo or combo. It looks for the antigen and antibodies. People that were found to have HIV reported that they first tested positive for the antigen but negative for antibodies (their body hadn't formed them yet).
If it was a Duo test then its pretty much conclusive. CDC still requires one more final test 12-13 weeks even if a Duo test was used. The PCR test can detect the virus itself as early as 10 days.
No, not ARS. You can't diagnose by symptoms anyway. You had a risk and your initial test was negative (you weren't "clear" as you are still in the window period). You had a second exposure so you need to test at 4-6 weeks and confirm at 13 weeks your final result.