CRP and COVID-19: Some studies have reported that vitamin D treatment could be helpful for COVID-19 prevention [140,146] or treatment because vitamin D plays an essential role as a modulator of immunocompetence [203,204,205], regulates B and T cells [141,143], reduces CRP levels [141], mortality [135,136,139], the time of hospital stay [142,143] and the need of oxygen support [142,148].