MPO and COVID-19: The highest values of NET markers were found in the plasma of severe COVID-19 patients, which showed significant differences from HI in the analysis of NE (45.3 ng/ml vs 12.88 ng/ml, p < 0.000001), MPO (90.85 ng/ml vs 11.91 ng/ml, p < 0.000001), and cirDNA (116 ng/ml vs 5.76 ng/ml, p < 0.000001).