PROS1 and COVID-19: These analyses, will include, amongst others the measurement of proteins induced by vitamin K absence (PIVKAs) and dephosphorylated-undercarboxylated matrix Gla protein (dp-ucMGP) and undercarboxylated osteocalcin levels to better understand the status of intra and extrahepatic vitamin K dependent proteins (VKDPs) in the COVID-19 patients.