4th gen ELISA VS ECLIA

Hello is the accuracy of ELISA and ECLIA the same? Most people say all combi/duo hiv tests are 95% conclusive after 4 weeks

[mqm]

4th generation combo tests look for BOTH antigen AND antibodies.What can cause the window period to increase? If a person does not do drugs,IV,PEP,not a transplant patient,is healthy.He should get accurate results after 4 weeks right?

[mqm]

But no matter how advanced the tests get,Teak will always tell you to get a retest after 3 months.

[Teak]

Those are the manufacturer's  and the FDA guidelines.

http://www.cdc.gov/globalaids/Resources/pmtct-care/docs/TM/Module_6TM.pdf
Page 11
#4
  In an adult, a positive HIV antibody test result means that the person is infected, a person with a negative or inconclusive result may be in the “window for 4 to 6 weeks but occasionally up to 3 months after HIV exposure. Persons at high risk who initially test negative should be retested 3 months after exposure to confirm results

UK Fourth Generation  Testing
http://www.bhiva.org/documents/Guidelines/Testing/GlinesHIVTest08.pdf
Post testing
Page 11
The need for a repeat HIV test if still within the window period after a specific exposure should be discussed. Although fourth generation tests shorten the time from exposure to seroconversion a repeat test at three months is still recommended to definitively exclude HIV infection.

[mqm]

"occasionally" the repeat test is just to remove all the doubts you have

[Teak]

If you do not like the  correct information you've received here feel free to take it to a different website.

[mqm]

Dr. Jose Gonzalez-Garcia, MD, MRCGP, PhD
HIV 1 and 2 antibodies and p24 antigen test (HIV DUO or HIV Combi test)

This HIV test is licensed in the EU for use after 28 days after a possible exposure. It is probably much better than this and will probably identify the majority of newly infected HIV positive individuals at between 14 and 21 days. This HIV test is referred to as a fourth generation HIV test. Certainly in our clinic we have had many new diagnoses of patients using this HIV DUO test combination in that time frame.

The HIV DUO test relies on the principle that when HIV first establishes itself in the body it will start to replicate rapidly and almost as a by-product of this replication a core protein - the HIV p24 antigen - is produced in huge amounts from around 10 days or so after first infection and before or during the time when antibodies to HIV are being formed. The p24 antigen will then stay at a very high level for the first few months after infection and later decline in line with the decline in HIV viral load as referred to above. It will though never completely disappear and will run a variable course of detection through the rest of the illness.

So in general, p24 antigen is formed slightly before antibodies are forming allowing us to close the gap between infection to detection time - the HIV window period. As time goes on, then the majority of newly infected HIV positive people will form antibodies to HIV 1 or 2 by 28 days. In combination then, looking for both the HIV 1 p24 antigen and also HIV 1 and 2 antibodies will allow for much earlier detection of HIV than looking for HIV antibodies alone.

[mqm]

And I'm sure I am part of the "majority"

[Teak]

There are no tests marketed or sold that can give a conclusive negative test result earlier than 3 months.

" Dec 06, 2011 To: jjllmm
Hello,
Thank you very much for your post and welcome to our forum.  I am afraid that it is going to be me answering your question, and not my colleague, Dr Sean.
It is certainly quite unfortunate that you had contracted herpes type 2 in this unprotected sexual encounter.  The negative test that you had at 8 weeks is certainly highly reassuring and a very good indication as it is possible to detect the HIV antibodies already at that stage.  However current UK guidelines still recommend to have a final test at 12 weeks for it to be considered final and fully conclusive.  Having said all that, and speaking out of my own clinical experience, I have never come across anyone testing negative at 8 weeks and then positive at 12 weeks.  Therefore I am very confident that you are HIV negative.
Best wishes,
Dr José "

[manik_45]

What is the latestt you seen turns pozs after negative reault?
Im not trying to post on some1 s post but its just right time
Thank you sir

[mqm]

Manik perfect question.Even I haven't heard of anyone turning positive after 5 weeks SPECIALLY on a 4th gen combo test!

[Teak]

You don't hijack other people's threads to ask questions post your questions in your thread.

[Teak]

* Anyone who continues to post excessively, questioning a conclusively negative result or no-risk situation, will be subject to action by MedHelp. Conclusively negative results or a no-risk situation will be based upon the criteria established by MedHelp’s doctors. Action will be taken as follows:
    * After excessive posting, a warning will be issued by MedHelp
    * Continuing to post regarding the negative result / no risk situation will result in a 3 day suspension
    * Continuing to post upon your return will result in a permanent ban.

[nursegirl6572]

The following is an excellent explanation from our own Dr. HHH about the reasons behind why different window periods are cited by different people:


"The confusion about seroconversion time (window period) comes from three main sources.

First, failure to understand that not all HIV tests are the same.  Older antibody tests took longer than current ones, but not all web sites or public health agencies have caught up with the difference.  Also, testing often now includes direct tests for the virus, such as PCR for HIV DNA and tests for p24 antigen.  For the combination of such a test plus antibody testing (e.g., the "4th generation", "duo", or "combi" test), the window period is only 4 weeks.  By that time, all infected people will have a positive result on one or both components of the two tests.

Second, legal conservatism.  Some agencies lean over backward to take no chance of telling someone they don't have HIV if they may be infected.  Their legal departments advise going even further than scientifically necessary in their advice about window periods.  That's where you may see advice about 6 months, even though all antibody test manufacturers claim their tests are 100% reliable by 3 months.

Third, regulatory issues.  A company producing a new HIV test may validate it by studying blood from a few thousand persons, of whom some are known to have HIV and others are known not be infected.  For those with HIV, the company's research team may decide to only study persons with infection known to be present 3 months or more.  The test may in fact detect everyone infected for 6 weeks or even less.  But since they have only studied those infected for 3 months or more, the US Food and Drug Administration (FDA) requires them to say a negative result may not be reliable until 3 months have passed.

For the antibody tests, the last issue is the most confusing.  Everything known about the speed with which antibody develops in response to a new HIV infection, and the ability of the tests to detect that antibody, indicate that the tests will pick up virtually all new infections by 6 weeks, and certainly by 8 weeks.  But because of the regulatory standards, the manufacturer may not claim 100% reliability until 3 months.  And given the manufacturers' stance, it's easy to understand why physicians, clinics, health departments, or other agencies feel they need to stick with 3 months in their formal advice.

I hope this helps clarify these issues.  For more information, see these threads as well (read them all -- the main information is in the follow-up comments).

http://www.medhelp.org/posts/show/1347755
http://www.medhelp.org/posts/show/1177982

Best regards--   HHH, MD




This paragraph from above explains nicely why we, on this forum, maintain our advice that a 3 month test is still necessary:

For the antibody tests, the last issue is the most confusing.  Everything known about the speed with which antibody develops in response to a new HIV infection, and the ability of the tests to detect that antibody, indicate that the tests will pick up virtually all new infections by 6 weeks, and certainly by 8 weeks.  But because of the regulatory standards, the manufacturer may not claim 100% reliability until 3 months.  And given the manufacturers' stance, it's easy to understand why physicians, clinics, health departments, or other agencies feel they need to stick with 3 months in their formal advice.

Until the formal guidelines change, our advice will not.  Like Teak said, you are free to believe any advice you receive.

[RainLover71]

The HIV DUO test is excellent at the 4 week mark and is extremely unlikely to change at 12 weeks.It has indentified many new HIV infections at this time frame.It is the test of choise in Australia,Uk and most of europe.Your figures are wrong about the DUO at 4 weeks,it's 99.89% accurate,not 95%.

[mqm]

My ECLIA 4th gen test result was negative at 5 weeks 3 days.Can that be considered conclusive? I am circumcised as well.

[mqm]

I also have a very strong immune system(judging by howmuch protein I eat everyday) and I also did not do PEP.

[mqm]

Nursegirl says its conclusive at 8 weeks.Why does everyone have different opinions about this test's accuracy?.Some people say antigens remain in your blood for a very long time and some say they completely decline by the 3rd week.

[nursegirl6572]

I didn't say it was conclusive at 8 weeks, that was a quote from our Dr. HHH.  Go back and carefully reread my post.  I offered a quote from Dr. HHH that very thoroughly explains the differing advice when it comes to the window period and why WE on this forum, stick to the official guidelines set by the CDC and testing manufacturers of 3 months.

[mqm]

according to the guide lines its not conclusive but according to common sense,it IS even after 4 weeks.

[nursegirl6572]

We could go round and round forever about this.  The fact is, the official guidelines have not changed, they remain at 3 months.  With the advances in testing, and with newly infected people testing positive early on, ANY negative result along the way is a good thing.

WE cannot decide for you what you are comfortable with.  If you feel that your test was sufficient proof for you that you are not infected, then that's fine, that's YOUR decision to make.  On THIS forum, we maintain that a follow up test at 3 months is the conclusive result, therefore, our advice won't change.

We can't keep going back and forth about this.  I've posted an excellent quote from Dr. HHH that explains the discrepancy in advice regarding the window period.  That's all we can do.  

[bangloren428]

is eclia test at after 42 day of exposure is reliable?

[LIZZIE LOU]

an antibody test is conclusive at 3 months post exposure

[manolis27]

Im very afraid. Today Ill take the last drug (PEP)... What about my situation? Both for p24, antibodies and of course pcr? please tell me exactly what you know...

The 23st day i started have a red neck without temperature, it finished after 7-8 days. I have to notice that i have it sometimes in the year. its not very new for me that neck.

But 2 days now, i feel my right hand heavy sth like the bllod is not "run" well....

I wait for all your experience

[nursegirl6572]

Your conclusive result can be obtained at 3 months after your last dose of nPEP....which will be three months from today.

If you need more info or have more questions, please start your own thread.