A small study found a strong association between HHV-6 infection of the placenta and intrauterine growth restriction—a finding consistent with other evidence linking HHV-6 to several reproductive diseases.
HHV-6A and 7 infection of T cells downregulates the protein tyrosine phosphatase, CD45
CD45, important in T cell receptor signaling, may be one mechanism by which roseolaviruses evade immune detection and help achieve latency
Levels of HHV-6B and HHV-7 DNA in saliva may distinguish people with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome from healthy control subjects
Levels of HHV-6B and HHV-7 DNA in saliva were higher in people with ME/CFS than in health controls and tended to be higher at times symptoms were worse. Similar correlations were not seen for other human herpesviruses.
Mothers with iciHHV6 have an increased risk of spontaneous abortion
27.6% of Japanese mothers with iciHHV6 had a spontaneous abortion compared to 14.8% of controls. iciHHV6 mothers were also 6.4X more likely to have two or more spontaneous abortions.
HHV-6A/B in brain disease: proposed criteria for establishing causation
Three top experts on HHV-6A/B teamed up to write a comprehensive review and propose criteria for establishing HHV-6A/B to MS, epilepsy and Alzheimer’s disease.
Foscarnet prophylaxis improved engraftment and survival in cord blood transplant patients
Six-month overall survival was 96% in the treated group compared to 72% in the untreated group.
Japanese study supports evidence of iciHHV-6 reactivation in vivo
Surprisingly, 72% of integrated genomes were found on chromosome 22q. Solo-DR sequences of HHV-6B were left behind after excision and reactivation.
HHV-6A and the suppression of miR155 in Alzheimer’s pathology
Dysregulation of the microRNA miR155 is associated with pathophysiological progression of Alzheimer’s disease. HHV-6A has been shown to suppress miR155.
Latent HHV-6B infection of astrocytes may increase the risk of depression by activating the HPA axis
Japanese investigators show that a protein expressed by latent HHV-6B in astrocytes, results in an influx of extra-cellular calcium, triggering the onset of depression.
Fetal iciHHV-6 associated with a 3-fold increased risk of preeclampsia
A large UK study utilizing RNA sequencing metagenomics of placental samples identified HHV-6 RNA in 6.1% of pre-eclampsia cases and 2.2% of healthy pregnancies. HHV-6 was the only virus found and it was iciHHV-6 in 70% of cases.
Active HHV-6/7 infection found in subset of adult epilepsy patients
HHV-6/7 DNA was found in the plasma of 19.6% of epilepsy patients compared to none of the controls. Protein expression indicating active infection was found in 53% of the HHV-6/7 positive patients.
Does HHV-6B reactivate in COVID-19 patients?
So far only one case report has documented HHV-6B reactivation in COVID-19, but the rise in Kawasaki-like symptoms and pityriasis rosea has at least one dermatology group suspicious of HHV-6/7 reactivation.
In DRESS/DIHS, early treatment with high dose steroids may suppress HHV-6; late treatment may prolong viremia
High dose steroids given in the first week appears to prevent HHV-6 reactivation in DRESS/DIHS patients by suppressing T-cell activation and serum interleukin-2 receptor (sIL-2R) levels. In contrast, a late start of steroid therapy resulted in a persistently high viral load for at least three weeks.
One step closer to understanding HHV-6A/B chromosomal integration
The mechanisms leading to HHV-6A/B integration are a subject of intense research by several laboratories. A new paper in PLoS Pathogens provides some understanding as to how HHV-6A/B may integrate host chromosomes.
Latent HHV-6, mitochondrial fragmentation and a hypometabolic state in ME/CFS patients
A team of virologists and metabolomics specialists collaborated to demonstrate how chromosomally integrated HHV-6 can be stimulated to secrete factors that simultaneously cause mitochondrial fragmentation, a reduction in intracellular ATP reserve and an expanded antiviral defense by their neighboring cells.