There are at least eight herpes virus variants that infect humans. These include: Human herpes virus 1 (HHV1) is also known as herpes simplex virus 1 (HSV1). Human herpes virus 2 (HHV2) is also called herpes simplex virus 2 (HSV2). Human herpes virus 3 (HHV3) is also called varicella-zoster virus. HHV3 causes chickenpox. Human herpes virus 4 (HHV4) is also known as the Epstein-Barr virus (EBV). Human herpes virus 5 (HHV5) is the official name of cytomegalovirus (CMV). Human herpes virus 6 (HHV6) Human herpes virus 7 (HHV7) Human herpes virus 8 (HHV8) Many of these, such as EBV and CMV, either downregulate the vitamin D receptor (VDR) or prevent vitamin D from metabolizing into the active form that stimulates that receptor. Some of these viruses are now considered to be potentially involved in Alzheimer's disease. A very powerful Taiwanese study found that patients over age 50 with particular Herpes Simplex Virus variants had a 250% higher chance of developing Alzheimer's. The stunning part of that study was that when they gave the patients common antivirals they completely reversed the disease risk. This leads me to make the observation that these very common human viruses may be co-infections that greatly lower our innate immunity, and therefore make the severity of our CFS conditions much worse. Should every CFS patient be running labs to determine their status of all eight Herpes viruses, and then treating these under medical supervision with antivirals? The hypothesis would be that with a lower viral load, the body's innate immunity will improve, thus allowing the body to fight many other kinds of bacterial and viral invaders more effectively.