HSV-1 Equivocal Results

[question22461]

I have some questions regarding HSV-1.  I had oral sex with a man who did not have any cold sores what so ever, but still, just to be safe I got tested.  I was tested for all STDs, everything was negative except for HSV-1 igm ratio 1:80, igg .92.  The test was performed at one month and a few days after exposure (I was not aware at the time it is best to wait 3 months).  My doctor told me I was positive for HSV-1, but that it was a good idea to get retested at the 3 month mark.  She said my igm suggested that the virus was new and that is why the igg number is low.  I did some research of my own online, and these are the questions I have.

1. Is there a formula to how igg levels increase?  For example if at one month after possible exposure, my level is .92, could we then assume that is will be double that in one more month?
2. Is 3 months from possible exposure long enough to wait to be tested
3.  I have been reading online that there is a range of equivocal results that my Dr. did not mention before (She also said greater than .89 was positive as opposed to .90) :

Negative: HSV 1 IgG Index of 0.90 or less are seronegative for IgG antibody to HSV 1.
Equivocal: HSV 1 IgG Index of 0.91 - 0.99 is equivocal. Sample should be retested.
Positive: HSV 1 IgG Index of 1.00 or greater are seropositive

Would I fall into the "equivocal" range?  If so, what if I test equivocal again?  I have been reading that is possible.  Can you assume negative if the results continue to be equivocal?
4.  Do low igg levels= low symptoms and low transmission?
5.  If I had never been exposed to HSV-1, would my test have been at 0?  Does everyone carry some level of igg antibodies?
6.  My Dr. mentioned she had seen people exposed to only a small amount in the early stages go to negative igg levels, but that is rare?  Is it possible to only be exposed to the virus in a small amount and still be negative?

[Terri Warren, RN, Adult Nurse Practitioner]

1.  No there is no formula, you should assume nothing about being positive or negative at this time.
2.  Three months is fine.  If your value goes down, you should be reassured about your negativity.  
3.  0.92 is equivocal, not positive, not negative, but kind of in between
4.  You can't assume anything at this time.  
5.  No, the test results are very rarely zero.  They most often have some value as they are compared to a control that has some value.  
6.  Nope, that doesn't make sense to me AT ALL.  That's like being exposed to a little sperm, so you are only slightly pregnant?  I don't think so.

Terri

[dmnich2]

A related discussion, herpes testing was started.

[Terri Warren, RN, Adult Nurse Practitioner]

92 is not a high value at all.  You may or may not be in the process of serconverting, there is no way to know from this one test, unfortunately.  Yes, it is certainly possible to move into the negative range if you are not infected.  I would consider the IgM test not useful until proven otherwise by a positive IgG.  It is certainly possible to get HSV 1 from oral sex, yes.  A test taken one month post exposure is really not reliable, either way, I am afraid.  You will really have to retest.  You can retest sooner than 4 months, and if it is much lower or much higher, it would certainly give you more information.

Terri

[question22461]

Hi Terri,

Thank you so much for your help.  Is it normal to test so high (igg .92) after only one month of possible exposure?   Is it even possible to go down to the negative range after testing at this number?  I read that these tests can be off as much as 1 whole value each time.  Also, I have read that igm tests are often times inaccurate.  Would this particular number (1:80) mean that the virus is a new infection?    How likely is it to get HSV-1 from oral sex?  And lastly, is there any accuracy to an HSV test taken only one month after exposure?

Thank you.