The December 2014 issue of Current Opinions in Virology features a "Special Section on Roseoloviruses." Top experts in the field contributed a set of 14 reviews that span a wide range of critical topics discussed at the recent June 2014 NIH-sponsored workshop “Roseoloviruses: Unmet needs and research priorities.”
The University of Washington and the Fred Hutchinson Cancer Research Center are at the forefront of studying the role of HHV-6 and ciHHV-6 in stem cell transplant patients. We asked their view on the implications immunocompromised patients with integrated HHV-6A reactivating with their own inherited virus.
Immunocompetent adults are not supposed to get HHV-6 encephalitis or status epilepticus (SE) and HHV-6 testing is rarely performed in these patients. A new case report from Baylor suggests that testing for HHV-6 in these patients may be worthwhile.
Dr. Flamand, a professor and molecular virologist at Université Laval in Quebec city, has written an editorial calling for screening of organ donors for ciHHV-6 status and careful monitoring of recipients of ciHHV-6 donor tissues for signs of active HHV-6 infection and HHV-6 antigen-induced immune rejection. Flamand also questions whether solid organs and stem cells derived from persons with ciHHV-6 should be used in transplantation.
The inherited strain of HHV-6A in an immunosuppressed infant activated and caused hemophagocytic syndrome that was responsive to antiviral treatment. The isolated strain matched that of his ciHHV6 father.
A sequencing study led by Ursula Gompels of London School of Hygiene & Tropical Medicine, found that 95% (19/21) of Czech ciHHV-6 malignancy and inflammatory disease patients had ciHHV6A while 65% (13/20) of a German myocarditis cohort had ciHHV-6B. The authors propose that this divergence suggests different disease links for the two viruses.
A group of researchers from The Children’s Hospital of Philadelphia evaluated HHV-6 levels in pediatric patients with drug hypersensitivity syndrome (DHS) and found HHV-6 reactivation to be less common than in adult cases of DHS.
A group from University College London and the University of Zambia has reported that 20.5% of hospitalized infants were positive for HHV-6B, second only to CMV (24.3%). In contrast to previous studies, HHV-6A was found in only 0.3% of patients.
The HHV-6 Foundation in a non-profit entity founded to encourage scientific exchange between investigators and to provide pilot grants for promising scientific and clinical research on the under- appreciated viruses HHV-6A and HHV-6B. The Foundation sponsors international conferences and supports scientists and clinicians seeking to clarify the role of the two HHV-6 viruses in disease. Since the HHV-6A and HHV-6B can smolder in the brain and other organs without circulating in the peripheral blood or plasma, identifying chronic infection is a challenge.
ciHHV-6 Patient Registry
Except for transplant patients, HHV-6 plasma DNA tests are rarely positive. Any patient testing positive should rule out chromosomally integrated HHV-6, a condition that may be associated with increased HHV-6 reactivation.