Aa
comparing tests
I'm a 25 year old white male with unprotected vag exposure to csw in south-am and wanna know the best tests to take.
Dna pcr 2 days after exposure- neg
Rna pcr 12 days after exposure- neg
Dr Hook told me before odds are strongly on my side
the doctors on this forum are always saying antibody/p24 combo test is basicaly 100% accurate at 4 weeks.
1- is there a reason you prefer antigen test versus a pcr test in combo at 4 weeks? Is it because of cost? Is antigen somehow at 4 weeks?
2 - I know antibody and pcr tests together at 4 weeks is also extremely strong evidence but is it virtually 100%?
3- what is the difference betteen rna and dna pcr in terms of results? Is one better to take within a certain window than the other?
4- are all antibody tests basically 100% accurate at over 6 weeks (oral swab, quick test, blood test etc)?
5- for me, given I have tests already at 12 days, would dna-pcr/antibody be virtually 100% at 4 weeks? Can I stop taking tests then and relax? Is there a way the virus can stay hidden/dormant beyond the 4 weeks and not be picked up by testing?
Not knowing your status is torture and I want peace of mind asap. thank you
Dna pcr 2 days after exposure- neg
Rna pcr 12 days after exposure- neg
Dr Hook told me before odds are strongly on my side
the doctors on this forum are always saying antibody/p24 combo test is basicaly 100% accurate at 4 weeks.
1- is there a reason you prefer antigen test versus a pcr test in combo at 4 weeks? Is it because of cost? Is antigen somehow at 4 weeks?
2 - I know antibody and pcr tests together at 4 weeks is also extremely strong evidence but is it virtually 100%?
3- what is the difference betteen rna and dna pcr in terms of results? Is one better to take within a certain window than the other?
4- are all antibody tests basically 100% accurate at over 6 weeks (oral swab, quick test, blood test etc)?
5- for me, given I have tests already at 12 days, would dna-pcr/antibody be virtually 100% at 4 weeks? Can I stop taking tests then and relax? Is there a way the virus can stay hidden/dormant beyond the 4 weeks and not be picked up by testing?
Not knowing your status is torture and I want peace of mind asap. thank you
MEDICAL PROFESSIONAL
You are welcome. Take care. EWH
It's hard to control the worry given th danger I may be in after being an idiot on one night but thanks for the long and detailed info. This site is a great place for advice
MEDICAL PROFESSIONAL
Welcome back to the Forum. You are really worrying too much. Here are the answers to your questions.
1. The combination p24 antigen/HIV antibody test has been studies for HIV screening and diagnosis in FDA approved studies and found to be highly accurate. The PCR test has not been studied for this purpose. In general we do not recommend HIV PCR testing for diagnosis is HIV infection for several reasons. While the PCR is likely to become positive more quickly than other antibody detection tests (i.e. usual blood tests), at the present time the blood tests are becoming more and more sensitive and detecting infection earlier and earlier so that the time difference in detection between PCR test and antibody detection tests is becoming smaller and smaller and at present is, in general only a week or two. In addition the time course over which the PCR tests become positive is less well described than for the blood tests and, as a result, it is difficult to make a definitive statement on what a negative PCR test means at any time within a few weeks of exposure to a HIV infected or possibly infected partner. PCR tests are also more expensive than regular antibody tests. Finally and most importantly, the false positive rate for PCR tests (i.e. a positive result in persons who do not have HIV) is higher than for blood tests. Each of this on this Forum have seen a number of people who were worried needlessly because of false positive tests. For all of these reasons, we rarely recommend testing for HIV diagnosis using PCR.
2. As a generalization for both you and other readers, you must realize that we VERY frequently get questions asking if different types of exposures or prevention measures are 100% effective. The answer to that is that this is scientifically impossible. For a variety of complex mathematical reasons far too complex to go into here, all one can do with well conducted scientific studies is estimate probabilities. By definition, any estimate, cannot be 100% certain. On the other hand, when Dr. Handsfield or I say that something is very close to no risk or of minimal risk, or use any other term to indicate a very small risk, that means "close to zero" in a world where zero cannot be attained.
3. No, RNA and DNA PCR tests have similar performance characteristics and sensitivity. We do not recommend either one for diagnostic testing.
4. No, all antibody tests are essentially completely reliable at 8 weeks, not 6. In some instances when the risk before testing is very, very low, the mathematical difference between a 6 and 8 week test is insignificant.
5. Yes, the combination of tests you describe would be just as good as a DUO test at 4 weeks as long as you do not get a false positive result, just more expensive.
6. The bleeding does not make a difference. EWH
1. The combination p24 antigen/HIV antibody test has been studies for HIV screening and diagnosis in FDA approved studies and found to be highly accurate. The PCR test has not been studied for this purpose. In general we do not recommend HIV PCR testing for diagnosis is HIV infection for several reasons. While the PCR is likely to become positive more quickly than other antibody detection tests (i.e. usual blood tests), at the present time the blood tests are becoming more and more sensitive and detecting infection earlier and earlier so that the time difference in detection between PCR test and antibody detection tests is becoming smaller and smaller and at present is, in general only a week or two. In addition the time course over which the PCR tests become positive is less well described than for the blood tests and, as a result, it is difficult to make a definitive statement on what a negative PCR test means at any time within a few weeks of exposure to a HIV infected or possibly infected partner. PCR tests are also more expensive than regular antibody tests. Finally and most importantly, the false positive rate for PCR tests (i.e. a positive result in persons who do not have HIV) is higher than for blood tests. Each of this on this Forum have seen a number of people who were worried needlessly because of false positive tests. For all of these reasons, we rarely recommend testing for HIV diagnosis using PCR.
2. As a generalization for both you and other readers, you must realize that we VERY frequently get questions asking if different types of exposures or prevention measures are 100% effective. The answer to that is that this is scientifically impossible. For a variety of complex mathematical reasons far too complex to go into here, all one can do with well conducted scientific studies is estimate probabilities. By definition, any estimate, cannot be 100% certain. On the other hand, when Dr. Handsfield or I say that something is very close to no risk or of minimal risk, or use any other term to indicate a very small risk, that means "close to zero" in a world where zero cannot be attained.
3. No, RNA and DNA PCR tests have similar performance characteristics and sensitivity. We do not recommend either one for diagnostic testing.
4. No, all antibody tests are essentially completely reliable at 8 weeks, not 6. In some instances when the risk before testing is very, very low, the mathematical difference between a 6 and 8 week test is insignificant.
5. Yes, the combination of tests you describe would be just as good as a DUO test at 4 weeks as long as you do not get a false positive result, just more expensive.
6. The bleeding does not make a difference. EWH
I should add I was bleeding after exposure due to sensitive glans
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