inclusion criteria: - inclusion criteria for donors: null-gravid, with a negative history of transfusion of blood components; possibility to sign the informed consent - inclusion criteria for covid-19 infected patients: serious covid-19 infection, possibility to sign the informed consent (also through the legal tutor)

inclusion criteria: - inclusion criteria for donors: null-gravid, with a negative history of transfusion of blood components; possibility to sign the informed consent - inclusion criteria for covid-19 infected patients: serious covid-19 infection, possibility to sign the informed consent (also through the legal tutor)