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Anonymous
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New HIV test Coming Window will be 12 days.
      #203962 - 08/18/06 12:15 PM

What will losers like Aids2Hiv say when this test comes out ? Just proves that the newer generation tests are more accurate than what the 13 week nazis are still saying. The Elisa test out there right now can detect HIV Antibodies in 21 days making the window 3-5 weeks but what will the 13 week nazis say about the newer test coming out ? I have some news for you nazis we already have newer tests it is called the 3rd generation and even the 4th Generation. Your information is old and outdated.

New HIV Test 25 Times More Sensitive Than Current Tests, Study Says
June 15, 2004

A new HIV test that identifies "tiny amounts" of p24 protein inside HIV is 25 times more sensitive than current HIV tests, according to a study published in the July issue of the American Journal of Clinical Pathology, the Wall Street Journal reports. The Real-Time Immuno-PCR test combines parts of traditional antibody testing with polymerase chain reaction, which "amplifies" small amounts of the virus. Currently, most viral load tests can identify 50 copies of HIV; however, the new test can detect the virus when only two copies of HIV are present, according to study co-authors Janet Barletta and Daniel Edelman of the University of Maryland School of Medicine Institute of Human Virology, the Journal reports. Study co-author Niel Constantine said he hopes that the technology used in the new test produces results faster than current tests, which can detect HIV in blood 12 days after a person has been exposed to the virus, according to the Journal. The test still must undergo long-term studies to gain FDA approval, the Journal reports. Constantine said that his research group also is developing a "simpler, cheaper system" to monitor HIV-positive people in the developing world who are on antiretroviral therapy, according to the Journal. He said that the portable HIV monitor -- which is being developed with a $200,000 grant from the Doris Duke Charitable Foundation through a partnership with Norway-based Bionor -- is battery-operated and could be used in settings "without reliable power or sophisticated labs," the Journal reports (Chase, Wall Street Journal, 6/15).


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AIDS2HIV
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Post deleted by Becky new
      #203966 - 08/18/06 12:31 PM



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Anonymous
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Re: New HIV test Coming Window will be 12 days. new
      #203970 - 08/18/06 12:53 PM

don't waste your time with A2H he is stuck on stupid.

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AIDS2HIV
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Post deleted by Becky new
      #203972 - 08/18/06 01:09 PM



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Anonymous
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Re: New HIV test Coming Window will be 12 days. new
      #203973 - 08/18/06 01:45 PM

That article from 2004 was talking about the 4th generation test. It is well established that combining the P24 antigen along with the ELISA reduces the window period. Massachusetts uses this test which is why they have dropped the window down to 6 weeks.

Also A2H, you are incorrect in your statement that the world uses the 3 month time frame. Most countries in Europe have used an 8 week window since the early 2000's. That's not surprising since Europeans don't get caught up in the puritanical aspects of morality.

This whole disagreement is nothing new. It was just as nasty back when the debate was between 3 months and 6 months, but times do change and science progresses. Once we get our puritanical president out of office we may very well see the window period officially lowered once again.

It IS a matter of better testing sensitivity, not how the human body works, with only small variances we all work the same.

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Anonymous
Unregistered

Re: New HIV test Coming Window will be 12 days. new
      #203981 - 08/18/06 02:33 PM

massachusetts does not use the 4th generation test. more bad info. they use a 3rd gen test. a 4th gen test at 6 weeks is a 3rd gen test. 4th are only good 1-3 weeks after infection. once again massachusetts does not use a 4th generation test.

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Anonymous
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Re: New HIV test Coming Window will be 12 days. new
      #204008 - 08/18/06 04:57 PM

"4th are only good 1-3 weeks after infection."

Wrong. The 4th generation is a COMBINATION TEST. It will pick up either the P24 OR antibodies.

While you are correct that P24 antigens can only be detected between 1-3 weeks after infection you totally ignore the ELISA component of the test. What cause the P24 antigen to disappear is the appearance of HIV antibodies. So if some is infected they would test postive on the P24 part of the test early on, or if they took the test slightly later, they would test postive on the ELISA part of the test.

And you want to talk about wrong information.

Since 2002 when this was written more advances have been achieved in HIV diagnoistics.
*****************************************
From http://www.mf.uni-lj.si/acta-apa/acta-apa-02-1/poljak.html

Retrospective evaluation of the Vidas HIV DUO test for simultaneous detection of anti-HIV antibody and p24 antigen
M. Poljak, D. Babič and K. Seme


Keywords
anti-HIV antibody;
p24 antigen detection;
simultaneous Vidas HIV DUO test

Summary
A fourth generation screening assay Vidas HIV DUO (bioMerieux, Lyon, France) which permits a simultaneous detection of anti-HIV-1/2/O antibodies and HIV-1 p24 antigen was evaluated on 927 serum samples with previously determined anti-HIV-1/2 status in a retrospective manner. The Vidas HIV DUO yielded sensitivity, specificity, positive and negative predictive value of 100%, 99.27%, 94.69% and 100%, respectively. The Vidas HIV DUO is a highly specific and sensitive anti-HIV screening assay, suitable for the implementation in the routine laboratory diagnostics of HIV infection.



Introduction
Current laboratory diagnosis of human immunodeficiency virus (HIV) infection is mainly based on the detection of anti-HIV antibodies (1). Since the introduction of anti-HIV screening assays in 1985, their performance has continued to improve. Recently, fourth generation screening assays which permit the simultaneous detection of anti-HIV antibody and HIV-1 p24 antigen have been developed. They are reported to reduce the diagnostic window by at least 6 days compared to third generation assays in cases with symptomatic infections (2-5). Five commercially available fourth generation anti-HIV screening assays are available at the moment: Vidas HIV DUO (HIV4) (bioMérieux, Lyon, France), Vironostika HIV Uni-Form II Ag/Ab (Organon Teknika, Boxtel, Netherlands), Enzymun-Test ® HIV Combi (Roche Boehringer Mannheim, Penzberg, Germany), Enzygnost HIV Integral (Dade Behring, Mannheim, Germany) and Genscreen plus HIV Ag-Ab (Biorad, Hercules, USA). According to the results of the first evaluations of the fourth generation HIV screening assays, they represent an important step towards earlier serologic diagnosis of HIV infection (2-5).

Because of an extreme genome variability of HIV-1 and HIV-2, each new anti-HIV screening test or even its variant should be evaluated in local settings before approval is granted by the government and the test is introduced in a routine work (1). Thus, the aim of the present study was to evaluate a fourth generation anti-HIV screening assay Vidas HIV DUO (bioMerieux, Lyon, France) on serum samples with previously determined anti-HIV-1/2 status, which were carefully selected from the collection of the Slovenian AIDS Reference Center.


Materials and methods
A total of 927 serum samples with previously determined anti-HIV-1/2 status were retrieved from the files of the Slovenian AIDS Reference Center. Serum samples were collected between 1985 and 1998, tested routinely for the presence of HIV-1/2 antibodies and stored at -20 0C.

All serum samples were previously tested for the presence of anti-HIV-1 and anti-HIV-2 antibodies using at least two different screening enzyme immuno assays in a routine manner. All repeatedly reactive serum samples were supplementary tested with confirmatory Western blot tests. The Western blot results were interpreted according to American Red Cross standards (6).

726 samples were anti-HIV-1/2 negative (they were all obtained from subjects with high risk of HIV infection, none of these samples was obtained from blood donors), 98 samples were anti-HIV-1 positive (51 serotyped as subtype B, five as subtype C, four as subtype A, one as subtype D and one as subtype E, 36 samples were not serotyped) and 9 samples were anti-HIV-2 positive (all obtained from subjects arriving from Central Africa). The most important group of samples consisted of 94 samples which tested anti-HIV reactive in one or more screening assays and anti-HIV-1/2 indeterminate using confirmatory Western blot tests. All these 94 samples were finally determined as anti-HIV-1/2 negative in follow-up testing.

All 927 serum samples included in a retrospective evaluation were tested in August 1998 using the fourth generation assay Vidas HIV DUO (bioMerieux, Lyon, France), according to manufacturer's instructions as described previously (6).


Table 1. Results of the retrospective evaluation of Vidas HIV DUO assay.



Anti-HIV status


Vidas HIV DUO
Negative Positive Total
Nonreactive
814 0 814
Reactive
6a 107 113
Total
820 107 927

a All 6 serum samples belonged to the group of 94 anti-HIV-1/2 indeterminate serum samples which were finally determined as anti-HIV-1/2 negative in follow-up testing (VIDAS HIV DUO false positive results).

Results
A total of 113 serum samples tested initially Vidas HIV DUO positive and 814 tested Vidas HIV DUO negative. After a final evaluation 107 serum samples were defined as Vidas HIV DUO true positive, 6 samples as false positive and 814 as true negative, yielding a sensitivity of Vidas HIV DUO of 100% and specificity of 99.27% (Table 1). All 6 Vidas HIV DUO false positive serum samples belonged to the group of 94 anti-HIV-1/2 Western blot indeterminate serum samples which were finally determined as anti-HIV-1/2 negative in follow-up testing. The positive predictive value of Vidas HIV DUO was 94.69% and the negative predictive value 100%.


Discussion
Recently, the fourth generation of HIV screening assays in which HIV p24 antigen detection is combined with anti-HIV-1, anti-HIV-2 and anti-HIV-1 group O detection have been developed. Comparative evaluations of the fourth generation HIV screening assays performed on the seroconversion panels have shown that the fourth generation HIV screening assays reduced the diagnostic window of HIV infection by an average of 7 days in comparison to the third generation HIV screening assays and that they permit an earlier diagnosis of HIV infection than third generation screening assays, by detecting p24 antigen which may be present in samples from individuals with recent HIV infection prior to seroconversion (2-5, 6-10).

The results of our retrospective evaluation showed 100% sensitivity and a very high specificity of 99.27% of Vidas HIV DUO assay, which is in accordance with the results of earlier evaluations (2, 3, 5, 8). The positive predictive value of the Vidas HIV DUO was very high (94.69%), which was the result of a low number of false positive results and a high prevalence of HIV infection (11.54%) in the artificially created population that was tested in our study. Namely, the number of false positive results decreases with the increase of prevalence of infection and accordingly the positive predictive value of the assay increases.

Since the fourth generation HIV screening assays combine two different test principles in one assay, the potential for nonspecific reactivity might be expected to be higher than with the third generation antibody assays. However, the results of our study did not confirm this presumption. Namely, the false-positivity rate of Vidas HIV DUO (6.3%) found in our study among 94 samples which tested anti-HIV reactive in one or more screening assays and anti-HIV-1/2 indeterminate using confirmatory Western blot tests was lower than that of our third generation enzyme immuno assays evaluated on the same samples previously (false-positivity rates ranged from 8.1% to 16.2%, data not shown).


Conclusions
In conclusion, the Vidas HIV DUO is a highly sensitive and specific anti-HIV screening assay. It is completely automated, cost effective, saves technician's time and is therefore suitable for implementation in the routine laboratory diagnostics of HIV infection.





References

Gürtler L. Difficulties and strategies of HIV diagnosis. Lancet 1996; 348: 176-179.
Gürtler L, Mühlbacher A, Michl U, Hofmann H, Paggi GG, Bossi V, Thorstensson R, Villaescusa RG, Eiras A, Hernandez JM, Melchior W, Donie F, Weber B. Reduction of the diagnostic window with a new combined p24 antigen and human immunodeficiency virus antibody screening assay. J Virol Methods 1998; 75: 27-38.
van Binsbergen J, Keur W, Siebelink A, van de Graaf M, Jacobs A, de Rijk D, Njiholt L, Toonen J, Gürtler LG. Strongly enhanced sensitivity of a direct anti-HIV-1/-2 assay in seroconversion by incorporation of HIV p24 Ag-detection: a new generation Vironostika HIV Uni-Form II. J Virol Methods 1998; 76: 59-71.
Weber B, Fall EHM, Berger A, Doerr HW. Reduction of diagnostic window by new fourth-generation human immunodeficiency virus screening assays. J Clin Microbiol 1998; 36: 2235-9.
van Binsbergen J, Siebelink A, Jacobs A, Keur W, Bruynis F, van de Graaf M, van der Heijden J, Kambel D, Toonen J. Improved performance of seroconversion with a 4th generation HIV antigen/antibody assay. J Virol Methods 1999; 82: 77-84.
C.D.C. Interpretation and use of the Western blot assay for diagnosis of human immunodeficiency virus type 1 infections. Morb Mortal Wkly Rep 1989; 38 (S-7), 1-7. 7. Yerly S, Simon F, Perrin L. Early diagnosis of HIV first infections: combined screening assay (p24 antigen and HIV antibodies). Schweiz Med Wochenschr 1999; 129: 319-22.
Brust S, Duttmann H, Feldner J, Gürtler L, Thorstensson R, Simon F. Shortening of the diagnostic window with a new combined HIV p24 antigen and anti-HIV-1/2/O screening test. J Virol Methods 2000; 90: 153-65.
Leperche S, Maniez-Montreuil M, Courouce AM. p24 Ag/anti-HIV combined tests in early HIV-1 infection. Transfus Clin Biol 2000; 7: Suppl 1:18-24.
Ly TD, Edlinger C, Vabret A, Morvan O, Greuet B. Contribution of combined detection assay of p24 antigen and anti-human immunodeficiency virus (HIV) antibodies in diagnosis of primary HIV infection by routine testing. J Clin Microbiol 2000; 38: 2459-61.




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Cobal
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Reged: 07/23/06
Posts: 136
Re: New HIV test Coming Window will be 12 days. new
      #204009 - 08/18/06 04:58 PM

Like A2H mentioned you failed to take into account the body needs time to respond before the test can detect the infection. He is not denying that the test may indeed be more sensitive, but without antibody production or viral replication you have nothing to test for.

Edited by Cobal (08/18/06 10:00 PM)

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Anonymous
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Re: New HIV test Coming Window will be 12 days. new
      #204012 - 08/18/06 05:01 PM

I maybe wrong on the 4th gen test being a combo test but I am not wrong on what Massachusetts uses they don't use a combo test. they use a standard antibody test. I have called them and talked to them.

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Anonymous
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Re: New HIV test Coming Window will be 12 days. new
      #204014 - 08/18/06 05:07 PM

They told me they did.

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Anonymous
Unregistered

standard new
      #204022 - 08/18/06 05:53 PM

I have also called the hotline and asked what test they use and was told a standard elisa test same as any other clinic in any other state.

When having a standard HIV antibody test, there must be at least six weeks time between the time a person was last at risk for contracting HIV and the time that he/she gets a test done. Some people call this the "window period". The HIV test is looking for antibodies, which are the body’s response to having HIV in it. For most people, it takes six weeks for the body to produce enough antibodies for a standard HIV antibody test to be accurate.

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RevAnn
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Reged: 08/17/06
Posts: 245
Loc: fort myers, florida
Re: standard new
      #204037 - 08/18/06 08:24 PM

Being from MA myself, I can tell you the Quest Diagnostics uses the newest tests available. However if you are calling just the clinic themselves, they would not generally know this. Also, your Dr can request the PCR/DNA test. My Dr would only trust the newest testing available, so he had all his labs sent to Quest.

--------------------
Namu-Myoho-Renge-Kyo

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Anonymous
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Re: standard new
      #204061 - 08/19/06 07:46 AM

Even if one test with a PCR, an ELISA still must be used for follow up. Neither PCR has been FDA approved for diagnostics as a stand alone test.



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Anonymous
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Re: New HIV test Coming Window will be 12 days. new
      #204081 - 08/19/06 11:45 AM

It's beed studied you idiots just don't get it. the average time it takes is 21-25 days. what do you think they studied lab rats ? rat boi eric ?

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nomoreworry4me
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Reged: 12/24/07
Posts: 127
Re: New HIV test Coming Window will be 12 days. new
      #235508 - 01/21/08 06:35 PM

For HIV - first test between 9-12 weeks (by that time about 95% of positives come back positive). Then test at 6 months, and then at one year (by one year 99.9% of positives are positive).

For STDs - it depends which one you are referring to - some are blood tests and some are swabs. If you know that you have exposed, just tell your doctor and she will treat you even before the test come back. In general, I would go with a 4-6 week rule - by then the bacteria or viruses would have time to replicate.


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