Aa
DNA TESTING... Teak or knowledgable person...
I tested negative 2 abn 5 weeks, and I scheduled a DNA test for next Tuesday Sept. 4. This will be at 7 weeks.
Would a DNA test be useless at the point in time?
I know that it is usually used to monitor viral loads, but won't it tell me definitively if I have HIV?
If my symptoms are from HIV wouldn't my viral load be high, and if I had symptoms at 5 weeks wouldn't I have antibodies?
Would a DNA test be useless at the point in time?
I know that it is usually used to monitor viral loads, but won't it tell me definitively if I have HIV?
If my symptoms are from HIV wouldn't my viral load be high, and if I had symptoms at 5 weeks wouldn't I have antibodies?
A few years back I had a DNA/PCR test done. My Doc who is one of the leading HIV experts in the Mid West told me they are the best for early detection. He said its all about the cost and that's why anti body tests are the standard period. Now that they have made the anti-body test so sensitive the last few years it is no longer necessary to get a DNA test unless you can't wait 4/6 weeks.
The porn industy uses the DNA test all the time. I think their last statistic was 1 false POZ in 5 years; enough about that hey?
The porn industy uses the DNA test all the time. I think their last statistic was 1 false POZ in 5 years; enough about that hey?
This is actually interesting, because this is not the first time that I hear about the PCR tests being used more outside of the US. I also didn't realize how cheap they were overthere - here a test like that must cost a few hundred dollars! I must admit that these tests are used so rarely here, that I myself know very little about them. I'll just throw my two cents over why I think doctors here don't like them, preferring ELISAs:
1) By its nature, a PCR is a tricky test, where a slightest error on the part of a lab tech can lead to big mistakes. Without going into details, a PCR is an amplification reaction, so any mistakes are amplified a thousand-fold - not so with an ELISA.
2) HIV has unbelievable genetic diversity, so it is harder to be sure that the PCR primers will match up with all HIV strains out there. On the other hand, ELISA looks for antibodies to viral structures, which are less variable than the genetic sequences. Besides, all the WWs are obsessed with things like HIV-2 - well, I don't think NAT tests detect any HIV-2 for example.
3) A fair number of infected people have no detectable RNA in their blood, but they still could infect other people and eventually progress to AIDS themselves. Unlike RNA, antibody is always detectable.
Bottom line is that the antibody test is all you need, people! The only people who need NAT are guys like porn stars, who could infect a dozen partners in a few weeks before seroconversion. So, unless you are in porn, wait out your 6-12 weeks and get a normal antibody test.
1) By its nature, a PCR is a tricky test, where a slightest error on the part of a lab tech can lead to big mistakes. Without going into details, a PCR is an amplification reaction, so any mistakes are amplified a thousand-fold - not so with an ELISA.
2) HIV has unbelievable genetic diversity, so it is harder to be sure that the PCR primers will match up with all HIV strains out there. On the other hand, ELISA looks for antibodies to viral structures, which are less variable than the genetic sequences. Besides, all the WWs are obsessed with things like HIV-2 - well, I don't think NAT tests detect any HIV-2 for example.
3) A fair number of infected people have no detectable RNA in their blood, but they still could infect other people and eventually progress to AIDS themselves. Unlike RNA, antibody is always detectable.
Bottom line is that the antibody test is all you need, people! The only people who need NAT are guys like porn stars, who could infect a dozen partners in a few weeks before seroconversion. So, unless you are in porn, wait out your 6-12 weeks and get a normal antibody test.
COMMUNITY LEADER
I just reported you cuz you did not end your comments today with your favorite line "always wear a jimmy"
I can also vouch about what o_g had to say, at least regarding DNA/RNA PCR tests in Asia. The are used often, recommended without any second thoughts, and in my opinion not too expensive. On the cheap the can cost around 60 USD, on the expensive they can cost 150 USD.
To the average person in Thailand that is expensive, but to most westerners living in Thailand... that amount of money is peanuts.
My results listed no numbers etc... it just saud negative.
any how, that is how things are done on this side of the pond. I hope I don't get reported for that!
To the average person in Thailand that is expensive, but to most westerners living in Thailand... that amount of money is peanuts.
My results listed no numbers etc... it just saud negative.
any how, that is how things are done on this side of the pond. I hope I don't get reported for that!
COMMUNITY LEADER
For the former part of your comment, I admit my ignorance and stand corrected, for the later part I completely understand that and have mentioned that above.
PCR tests in the US including RNA screening test are not approved standing alone tests for diagnostic purposes. They must be followed up with a antibody test. The tests are expensive in the US and have a higher risk of false positives.
Looking at things for as long as I have been, I get a feeling that doctors in the U.S. for some reason are hesitant to give a go ahead to DNA PCR test for people with exposures. But, come to Europe and Asia, go to any HIV specialist, he is going to recommend either a DNA or RNA PCR. Moreover, the pathology labs who carry out these tests go a step further in saying that no further test is even needed after the PCR's. Moreover, the path labs even in the USA recommend DNA PCR.
Again, Teak, I am not justifying their use. I am providing iformation from my 1st hand experience.
Now, there is a difference between the 2 PCR's.
RNA PCR which essentially is the viral load test is most efficient to detect infection (Qualitative RNA PCR not quantitative) within 1st 2 weeks after the risk/exposure. Beyond, that point, DNA PCR is superlative and once positive remains positive for life. The reason being that HIV resides in thymus, where the white blood cells are created. DNA PCR looks for infection in WBC's and strictly for infection detection purposes, even if the person is undetectable on viral load (RNA PCR) test, the infection can be determined on DNA PCR.
These are my 2 cents. Not to say,I recommend these 2 tests for anybody as antibody test is golden rule.
Again, Teak, I am not justifying their use. I am providing iformation from my 1st hand experience.
Now, there is a difference between the 2 PCR's.
RNA PCR which essentially is the viral load test is most efficient to detect infection (Qualitative RNA PCR not quantitative) within 1st 2 weeks after the risk/exposure. Beyond, that point, DNA PCR is superlative and once positive remains positive for life. The reason being that HIV resides in thymus, where the white blood cells are created. DNA PCR looks for infection in WBC's and strictly for infection detection purposes, even if the person is undetectable on viral load (RNA PCR) test, the infection can be determined on DNA PCR.
These are my 2 cents. Not to say,I recommend these 2 tests for anybody as antibody test is golden rule.
Mike, for you information my VL has never been in the millions. I don't know of to many people that have had their VL in the millions. In the hundreds of thousands but not millions. Mike if one has an undectable VL they can still be positive, that has nothing to do with antibodies detection. That is the reason for HAART medication is to get one VL down to undectable so that their body can produce more CD4s.
COMMUNITY LEADER
Correction:
4. There is a rare possibility of having an undetectable viral load even though one's infected and that possibility is ruled out by a negative antibody at the 8th week.
4. There is a rare possibility of having an undetectable viral load even though one's infected and that possibility is ruled out by a negative antibody at the 8th week.
COMMUNITY LEADER
If a person has a risk and he'd gotten a DNA PCR at the 28th day along with a negative antibody at 8 weeks, he'd be in the clear.
Why?
1.PCR would looks for the viral DNA
2. Once infected the viral load is in millions (since the virus replicates in millions every day)
3. These viral load tests are very sensitive and looks for as low as 10 copies of DNAor RNA / ml of blood whereas in an infected individual the viral load should be in 6/7 digits (bare minimum)
4. There is a rare possibility of having an undetectable viral load even though one's infected and that possibility is ruled out by a negative at the 8th week.
I hope this helps !
Why?
1.PCR would looks for the viral DNA
2. Once infected the viral load is in millions (since the virus replicates in millions every day)
3. These viral load tests are very sensitive and looks for as low as 10 copies of DNAor RNA / ml of blood whereas in an infected individual the viral load should be in 6/7 digits (bare minimum)
4. There is a rare possibility of having an undetectable viral load even though one's infected and that possibility is ruled out by a negative at the 8th week.
I hope this helps !
so...if a person had a risk 28 days ago and they went and got a PCR DNA backed up by a antibody test @ 28 days...the chance of them being +ve would be virtually rare?
I dunno. I have such LITTLE knowledge about PCR DNA, RNA, etc.
I dunno. I have such LITTLE knowledge about PCR DNA, RNA, etc.
COMMUNITY LEADER
Sorry for keeping the language a little confusing, that's what I meant "these levels will NOT become NONE detectable over time" = " these levels will never be undetectable" (unless on ART)
you state:
"But on the other hand PCR DNA tests are best used from 28 days on, but as early as 2 weeks, b/c these levels will not become none detectable over time. "
I had read a comment on here...which sticks in my head,....from Dr. H that said...
"Once the PCR DNA is positive,.it is positive for life".
That meaning of course if the person was infected with HIV.
Am I reading your quote right? Just a thought.
B.
"But on the other hand PCR DNA tests are best used from 28 days on, but as early as 2 weeks, b/c these levels will not become none detectable over time. "
I had read a comment on here...which sticks in my head,....from Dr. H that said...
"Once the PCR DNA is positive,.it is positive for life".
That meaning of course if the person was infected with HIV.
Am I reading your quote right? Just a thought.
B.
COMMUNITY LEADER
Nucleic Acid Test (Polymerase Chain Reaction) :
1. PCR (NAT) tests directly look for the virus in the body unlike the Antibody test which looks for the body's response to the infection
2. PCR tests can tell you if your body is infected as early as 72 hrs after the exposure
3. PCRs are lately approved for diagnostic purpose however doctors may order for NATs if they feel that one is going through ARS since it enables appropriate treatment by early detection of the virus
4. Theoritycally PCR can detect the virus as early as 72 hrs after the infection and the detection just keeps getting better along with the time since the HIV virus replicates itself in millions every day which means viral load keeps increasing every single day after the infection. For practical purposes one should wait atleast for 10 - 12 days aftr the exposure in order to get a PCR test
5. Comparisn RNA PCR / DNA PCR:
Another type of test is an RNA test, which detects the HIV virus directly. The time between HIV infection and RNA detection is 9-11 days. These tests, which are more costly and used less often than antibody tests
http://www.cdc.gov/hiv/topics/testing/resources/qa/be_tested.htm#wait
But RNA (viral loads) can become not detectable in some (meaning not many) cases when the body finally fights back. But on the other hand PCR DNA tests are best used from 28 days on, but as early as 2 weeks, b/c these levels will not become none detectable over time.
So in short less then a month or during ARS, PCR RNA tests is best (9 -11 days after the exposure) but after a month a PCR DNA test would be best, but at this point an Elisa test would work just as good and without the risk of false positive which would make most people here go crazy.
6. RNA PCR is for early detection, test at the 14 th day after the exposure backed up by an antibody test at the 6-8th week is good enough to rule out HIV.
DNA PCR at the 28th day after the exposure backed up by an antibody test at the 6-8 th week is good enough to rule out HIV
Both are NAT tests and are highly sensitive.
7.Drawback(very very unlikely though)
In some HIV positive individuals there are cases of undetectable viral load however a hypersensitive viral load test ( sensitivity - 50 copies / ml, 10 copies / ml) are good enough to detect the presence of the virus in the body.
8.Misconception about the PCR test (False Positives)
False positive rates have drastically dropped and every positive PCR is confirmed with another PCR for confirmatory reason, this eliminates the possibility of false positives, they are very reliable after 28 days, your result would be conclusive, however just for your own peace if mind back it up with a confirmatory test at the 8th week and move on.
In a nutshell, if you have the money to spend RNA / DNA PCR is a great test but one has to back it up with an antibody yest for confirmatory reasons only.
As per my research, Most of the experts haven't seen a negative PCR result changing ahead.
1. PCR (NAT) tests directly look for the virus in the body unlike the Antibody test which looks for the body's response to the infection
2. PCR tests can tell you if your body is infected as early as 72 hrs after the exposure
3. PCRs are lately approved for diagnostic purpose however doctors may order for NATs if they feel that one is going through ARS since it enables appropriate treatment by early detection of the virus
4. Theoritycally PCR can detect the virus as early as 72 hrs after the infection and the detection just keeps getting better along with the time since the HIV virus replicates itself in millions every day which means viral load keeps increasing every single day after the infection. For practical purposes one should wait atleast for 10 - 12 days aftr the exposure in order to get a PCR test
5. Comparisn RNA PCR / DNA PCR:
Another type of test is an RNA test, which detects the HIV virus directly. The time between HIV infection and RNA detection is 9-11 days. These tests, which are more costly and used less often than antibody tests
http://www.cdc.gov/hiv/topics/testing/resources/qa/be_tested.htm#wait
But RNA (viral loads) can become not detectable in some (meaning not many) cases when the body finally fights back. But on the other hand PCR DNA tests are best used from 28 days on, but as early as 2 weeks, b/c these levels will not become none detectable over time.
So in short less then a month or during ARS, PCR RNA tests is best (9 -11 days after the exposure) but after a month a PCR DNA test would be best, but at this point an Elisa test would work just as good and without the risk of false positive which would make most people here go crazy.
6. RNA PCR is for early detection, test at the 14 th day after the exposure backed up by an antibody test at the 6-8th week is good enough to rule out HIV.
DNA PCR at the 28th day after the exposure backed up by an antibody test at the 6-8 th week is good enough to rule out HIV
Both are NAT tests and are highly sensitive.
7.Drawback(very very unlikely though)
In some HIV positive individuals there are cases of undetectable viral load however a hypersensitive viral load test ( sensitivity - 50 copies / ml, 10 copies / ml) are good enough to detect the presence of the virus in the body.
8.Misconception about the PCR test (False Positives)
False positive rates have drastically dropped and every positive PCR is confirmed with another PCR for confirmatory reason, this eliminates the possibility of false positives, they are very reliable after 28 days, your result would be conclusive, however just for your own peace if mind back it up with a confirmatory test at the 8th week and move on.
In a nutshell, if you have the money to spend RNA / DNA PCR is a great test but one has to back it up with an antibody yest for confirmatory reasons only.
As per my research, Most of the experts haven't seen a negative PCR result changing ahead.
If it was unprotected vaginal or anal then yes you still need to go back and get retested.
Got the PCR DNA and the ELIZA test today at 45 days. If it comes back negative should I still go back at 12 weeks and if it comes back positive what should I do then besides curl in a ball for a while?
I have had around 4 DNA PCR tests no big deal. Neve have I had a false positive or positive result for that matter.
I followed them up with an anitbody test latter. I used the DNA test like Prozac more than anything.
I followed them up with an anitbody test latter. I used the DNA test like Prozac more than anything.
Yes, I agree. As usual, Teak and I are discussing matters completely unrelated to the original post :)))
reagardless,...I would not suggest the PCR at all for someone who is at risk....would you not agree?
Is not an antibody test is for?
B.
Is not an antibody test is for?
B.
I looked it up real quick, and the bDNA PCR actually detects HIV RNA not DNA. It is used for viral load tests, like you said. But the DNA PCR used for HIV testing actually detects proviral DNA and that is probably what tg4nrg is about to pay for.
In other words a bDNA PCR is NOT a DNA PCR.
So, tg4nrg, my advice stays the same, including the first sentence :)
In other words a bDNA PCR is NOT a DNA PCR.
So, tg4nrg, my advice stays the same, including the first sentence :)
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