The good news about herpes testing is that more and more clinicians are learning about blood testing that can identify those who are infected but don’t know it. The bad news is that they are often ordering a poor test called IgM blood antibody testing. The IgM test, with other viruses, comes up early in the infection and goes away when another antibody, called IgG comes up subsequently.
However, with herpes, there are significant issues with the IgM test. It can’t accurately distinguish type 1 from type 2, so a person could be told they have brand new genital herpes when all they have is old cold sore infection. It also can’t accurately distinguish herpes simplex virus from other herpes viruses, like chicken pox. And about a third of people infected with HSV 2 make new IgM with a recurrence, so it really can’t tell old from new infection, which is often why clinicians order the test.
PLEASE, if you’ve been diagnosed with herpes by a blood antibody test, get a copy of your results, and make sure they are IgG results, not IgM results. If you were positive by IgM and not by IgG, and at least 3-4 months have passed since your test, ask for an IgG test. If its negative, then the IgM was wrong.
And when you do this, let your clinician know the IgM is not a reliable test for herpes antibody. If it were me, I wouldn’t pay for that test, period. Be proactive about your herpes status – be certain your diagnosis is correct.