EPO and COVID-19: Contrary to our results, in a study by Maira et al. [44] involving hospitalised COVID-19 patients, when patients were categorised by severity of hypoxemia on admission (PaO2/FiO2 < 150 mmHg vs. PaO2/FiO2 ≥ 150 mmHg), no difference in hepcidin and EPO was observed between groups at admission to the ward or after 7 days of hospitalisation, although the hypoxemic group had a higher level of inflammatory markers.