1 Department of Clinical and Experimental Medicine, University of Florence, Florence, Italy.
2 Department of Clinical and Experimental Medicine, University of Florence, Florence, Italy; Division of Infectious Diseases, Careggi University Hospital, Florence, Italy.
3 Department of Clinical and Experimental Medicine, University of Florence, Florence, Italy; Division of Infectious Diseases, Careggi University Hospital, Florence, Italy. Electronic address: lorenzo.zammarchi@unifi.it.