MPO and COVID-19: As observed with other pathological conditions (e.g., sickle cell disease) (Ansari et al., 2021), NET levels are increased in COVID‐19 patients, with sera from COVID‐19 patients being shown to trigger NET release from control neutrophils and containing increased myeloperoxidase‐DNA (MPO‐DNA) complexes and citrullinated histone H3 levels, which correlated with disease severity (Veras et al., 2020; Zuo et al., 2020).