The reason the IgG test fails so often finally determined

[StayingUpbeat]

http://www.upi.com/Health_News/2015/08/11/Studies-may-lead-to-universal-test-for-oral-genital-herpes/5341439321177/

After years of the IgG blood test failing to accurately diagnose HSV in Africa investigation of the genetic diversity of IgG in HSV strains from around the world showed that the current blood test (against a single version of the IgG protein) is wildly insufficient to detect all strains of HSV-2.

To those who were told they are crazy or forced to hear that it couldn't be from a dirt-bag partner when they swab culture tested positive and he/she blood tested negative this should be an incredible vindication.

Let's hope the new IgG DNA sequences get moved RAPIDLY into the HerpeSelect to put an end to the ridiculous ambiguity of the current blood tests.

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[Bukx]

Thanks for the info !

[WilsoInAus]

This is not the correct interpretation of this paper.

The paper actually proves that the genetic variation of strains of HSV-2 is quite minimal meaning that existing tests are very accurate. The issue with the African population is a problem with false positives and not false negatives.

Any refinements to glycoproteins will improve the false positive issues, but will not dramatically alter the false negative outcomes which are exceptionally minimal.

[Voyager2]

Let's hope Quinn is correct----

"The fully mapped genomes of HSV2 strains also may lead to the development of a vaccine for the virus because researchers now have an understanding that the strains are not all that different, which may mean fewer antigens will be needed for inoculation, Quinn said."

[WilsoInAus]

That is a good aspect of the study. Although surprisingly this is not a new finding. Although perhaps not as widespread geographically, other studies have found that fewer strains for HSV-2 exist. HSV-1 on the other hand has many more strains and will be harder to vaccinate against.

[StayingUpbeat]

This is not the correct interpretation of this paper.

The paper actually proves that the genetic variation of strains of HSV-2 is quite minimal meaning that existing tests are very accurate. The issue with the African population is a problem with false positives and not false negatives.

Any refinements to glycoproteins will improve the false positive issues, but will not dramatically alter the false negative outcomes which are exceptionally minimal.

[uSER=46904]@WilsoInAus[/uSER] I apologize for referencing the article instead of the paper: http://jvi.asm.org/content/89/16/8206.full.pdf+html but you're really missing the forest for the trees here. It's finally becoming clear that a global HSV-2 antibody test with a single gG2 protein sequence is as ineffective as a universal HSV-2 vaccine with a single gD2 sequence.

Though you're correct that having a glycoprotein profile implying HSV-1 when you actually have HSV-2 is less frequent it still goes both ways. In certain HSV-2 clades the IgG serology also incorrectly identifies HSV-2 as HSV-1. If it's false positive for HSV-1 and you use a type specific IgG test looking for HSV-2 (and only HSV-2) it would simply show negative for HSV-2.

From the paper:

African subset for gG, gI, and gE contain numerous regions with enough sequence identity for the development of new (ELISAs) that would improve the diagnostic serology for HSV-1 and HSV-2.

And:

Future studies will explore whether other HSV-2 glycoproteins or gG consensus sequences are more suited for antibody detection assays.

I wouldn't expect the same group that has beat the drum for 20 years on how great the IgG antibody test is to drop a mia culpa unnecessarily. It would hurt their likelihood for funding and quite frankly for the amount of progress their work has enabled they shouldn't have to. What I happily expect will happen is that new IgG ELISA tests will include the new consensus IgG sequences and a new crop of sub-unit vaccines (that may actually work) will emerge.

People who've been told their bodies don't produce antibodies or that the partner they almost certainly caught it from is exonerated from existing serology tests should take from this study that, although good, these tests are clearly far from perfect and should be taken, at least for now, in the context of reality.

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[WilsoInAus]

Your conclusion though is still not supported by the paper. They do NOT say that IgG tests have false negatives at levels higher than previously acknowledged.

Although they have identified different strains of HSV-2, this does not mean that a person's IgG antibodies won't attack all strains of glycoprotein, which for HSV-2 does appear to be quite true given the lack of diversity in the strains.