IMO, current standard tests for herpesviruses don't mean much for PWME. To get a feel for the problems with herpesvirus tests, read this chart about HHV-6 tests: http://www.hhv-6foundation.org/patients/hhv-6-testing-for-patients. Tests for other herpesviruses can have similar problems. These tests were not designed to detect reactivated infections, particularly in people with immune abnormalities. As I understand it, the main reason EBV was dismissed years ago was that some patients' tests indicated that they had never been infected with EBV (negative IgG) and therefore EBV could not be the cause of ME. It was not considered that 1) those patients could be not producing enough antibodies to be detectable because of an immune deficiency, or 2)one of several herpesviruses might cause ME, not only EBV. HHV-6, for example is looking like a likely candidate. IMO, herpesvirus tests are close to worthless for PWME. And it's extremely difficult to get a doc to prescribe a potentially dangerous antiviral like Valcyte without some evidence of an infection. Valtrex is pretty safe, though, so you might convince a doc to prescribe it, but not for the length of time usually needed for PWME.