A group from University Hospital Arnau de Vilanova and Santa Maria, Spain, etc. has reported that miRNA profiles could be good markers for COVID-19
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8149473/
The expression levels of circulating miRNAs were compared between ward and ICU patients. Ten of 41 miRNAs were differentially detected.
Multivariate predictive models were constructed to discriminate ward patients from ICU patients, and the obtained AUC reached 0.89 (95% CI: 0.81-0.97) which was comparable to, or even higher than, that observed for the contemporaneous test proposed as biomarkers of COVID-19 severity, such as leukocyte counts (AUC=0.72), D-dimer (AUC=0.87) or CRP AUC=0.72).
Additionally, it was studied whether the circulating miRNA signature constitutes a predictor of mortality in critically ill patients or not. Six miRNAs (miR-16-5p (FC=0.69), miR-92a-3p (FC=0.78), miR-98-5p (FC=0.56), miR-132-3p (FC=0.69), miR-192-5p (FC=0.66) and miR-323a-3p (FC=0.66)) showed significant suppression in patients who did not survive the ICU stay. The multivariable analysis selected a signature based on two miRNAs (miR-192-5p and miR-323a-3p) that was could be a predictor of mortality during the ICU stay [AUC = 0.80 (0.64-0.96)].