Both HHV-6 and specific microRNAs may correlate with neurological symptoms in COVID-19.
Herpesvirus Reactivation Common in Severe COVID-19
HHV-6 was the most common herpesvirus found when tested in nasal swabs, but EBV was the most common in plasma.
Systematic review of pityriasis rosea following COVID-19 and/or vaccination
Pityriasis rosea was reported more frequently after vaccination than during or after acute infection.
Are herpesviruses reactivated more often in acute COVID-19?
Systematic review and meta-analysis found strong evidence for EBV in the seriously ill; only 6 of 36 studies included HHV-6 testing.
EBV and HHV-6 plasma viremia is infrequent at Day 7 during acute COVID-19
Other studies have suggested that reactivation of these viruses could theoretically contribute to a hyperinflammatory state or autoimmune disorders in acute COVID-19, but this study does not provide evidence of that.
The presence of HHV-6 DNA in nasal swabs correlates with neurological symptoms in patients with severe COVID-19
40% of the patients with HHV-6 DNA had CNS symptoms, compared to 14.3% of the HHV-6 negative patients.
Reactivation of herpesviruses demonstrated in severely ill patients with acute COVID-19
EBV, CMV, and HHV-6 reactivation were found in a small cohort of severe COVID-19 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.