A method of diagnosing a subset of Epstein Barr Virus, Myalgic Encephalomyelitis Chronic Fatigue Syndrome (ME/CFS) patients through a multi-prong clinical/serological analysis is provided wherein Epstein Barr Virus Abortive Lytic Replication (EBV) is determined by detecting the presence of BMRF1 in serum antibody assays. A method of treating patients diagnosed with Epstein Barr Virus Abortive Lytic Replication (EBV), Myalgic Encephalomyelitis Chronic Fatigue Syndrome (ME/CFS) with specific antiviral nucleosides is also provided, to alleviate the condition.