I think that the percentage that it is a false positive is probably greater than 90%.
We believe false positives are likely the result of the test being unable to distinguish between herpes antibody proteins and other proteins. It is well known that these tests have very high rates of false positives and the center for disease control recommends that they not be done unless someone is displaying symptoms of herpes or has had a partner with herpes and wants to know if they got infected themselves.
You could do the western blot as a confirmatory test if you wish to know for sure if you are infected with HSV one and or HSV two. Both are low positive results.
Terri