NETs are also involved in ARDS, a common complication of COVID-19; therefore, NETs biomarkers, such as cfDNA, histones, MPO, and NE, among others, have also been described as potential forecasters of COVID-19 prognosis, specifically that associated with short-term mortality, ICU admission, mechanical ventilation, lung damage, and SOFA score. The gene discussed is MPO; the disease is COVID-19.