IgG test is the most accurate and reliable on the Market, if there are antibodies in her system and it has been longer then four months since exposure then it will show up, Herpes can take up to 2-25 days to show symptoms, some people never have any. Has she been exposed to Chicken Pox or anyone with Shingles which is Herpes Zorter, the adult form of chicken pox? I would ask the doctor to be more specific in diagnoses. I hope this helped you.. Take Care and best wishes to your child. :)