HHV 6/HHV 7

Robin Avery, M.D., Paul Auwaerter, M.D.

MICROBIOLOGY

  • HHV-6 [Fig 1] and HHV-7 are members of the β-herpesvirus family.
  • Closely related to each other and CMV.
  • HHV-6 infects mature T-lymphocytes (CD4>CD8), monocytes, macrophages, megakaryocytes and glial cells. Remains dormant in PBMCs.
    • HHV-6 has 2 subtypes:
      • 6A: only accounts for 1-3% of disease, maybe more neurotropic.
      • 6B: appears responsible for most disease in solid organ transplant (SOT)/hematopoietic cell transplant (HCT)/immunocompromised populations.
      • Approximately 1% of the population has chromosomally integrated HHV-6 (ciHHV-6), sometimes leading to unnecessary treatment for HHV-6
  • HHV-7 infects T-lymphocytes (CD4>>CD8).

There's more to see -- the rest of this topic is available only to subscribers.

Last updated: July 4, 2022