[Question #4852] HSV2 Conundrum- one test negative and one positive

26 months ago
My new partner took the 10 test STD panel a month or so ago, which included the IGG test for HSV1 and HSV2. His results were negative except for the HSV2 IGG which came back positive with a very high 18.9 count of antibodies. Since he has never had any symptom and never been with anyone else who has ever had a symptom or told him about such a disease, he was very surprised. He then went on to get the DNA test (PCR) and received a negative result. Is the DNA test much more accurate than the IGG one and how does one explain that first result? Would he need a third test to confirm he does not have the disease or can he rely on this last one? 
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
26 months ago
The PCR test should only be done from a lesion  - some clinicians mistakenly use the PCR blood test which is useless.  The blood test looks for virus in the blood, which almost NEVER happens.  The IgG with an index value of 18.9  indicates that he is both infected and potentially infectious to others.  I don't believe that he needs another test to confirm his infection.  He will give off virus even when he has no symptoms at all.  This happens on about 10% of days in a person who is infected but has no symptoms.

Terri
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26 months ago

Thank you for your response. Just a few follow ups on your answer. 


  1. First of all, is it possible that the IGG can be showing that value to something else (I.e. cross reactivity, Varicella).
  1. The IGG test was done via Labcorp, and I’ve heard there might be false positives ? Is that true? Would a Western Blot test be more conclusive? 
  1. Regarding your answer that the PCR blood test shouldn’t be used on asymptomatic patients, do all the experts share that opinion? Because I’ve seen clinical trials where PCR blood test was used on asymptomatic patients and found more positives than IGG testing. Plus why would it be offered by many doctors and health labs as a blood test vs a culture if not at all relevant? I’m a little confused. 
  1. Can you explain viral shedding a bit more? Is shedding usually a phenomenon that occurs without symptoms and when there’s no evidence of it in the blood ? How does that happen? 
  2. What can we do to lower the risks? Condoms? Oral dam? Do antivirals lower the risk completely? And how long after taken do they work?
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
26 months ago
Sorry, Shelly, we've been traveling without internet
1.  No, not with a value that high
2.  False positive normally happen when the index value falls between 1.1 and 3.5.  I have seen higher ones but nothing this high
3.  Yes, all experts share that opinion.  PCR from blood might be used for an infant, for example, where disseminated infection is possible.  It should be use as an alternative to culture, not from blood
4.  Shedding is just giving off the virus from the body and happens with and without symptoms.  This is a skin and nerve disease, the nerve can bring the virus to the surface of the skin where it is then given off from the body.
5.  He can take daily antiviral medicine and use condoms when having sex with you. He should take it five days in advance for greatest safety, but it alone does not eliminate transmission to you.  Condoms reduce transmission by 96%

Terri
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