the igm is falsely positive 1/3 of the time in one study. it's sensitivity and specificity also really varies a lot from brand to brand.
Hi Grace, I didn't see that thread before when I'd searched, thank you so much for directing me to it.
I will re-test in a few months to confirm the negative IgG and post the results here.
I still don't quite understand why IgM is less reliable, but my impression from that thread is there are two issues, (1) it is non-specific and can give positive even if it's just HSV-1, and (2) it just has lower accuracy and many false positives. In my case, the contradiction between results means reason #1 is not the relevant one, but reason #2 is.
I would love to know where more info on the accuracy of the different tests can be found. What percentage exactly of IgM is false positive? What does it mean if I've had two in a row IgM positive results, and a slight increase in the second (not sure if the increase is statistically significant). If I knew more about the reason IgM often gives false positive, that might help elucidate my repeated positive results.
Also I'd love to see in the literature different studies for the latency period of appearing and disappearing of the IgM and IgG antibodies in blood tests. So if anyone has these infos please post!
Thank you Grace and others!
we don't recommend the herpes igm test here.
http://www.medhelp.org/posts/STDs/Confusiion-over-other-IgM-Herpes-posts/show/248394 is a prior post by HHH that nicely explains why we don't for more reading. a + igm herpes result is pretty much meaningless.
at this point wait until 3 months after the last time you had sex and retest and go from there. the risk from protected sex is pretty low.
grace