Department of infectious and tropical diseases, Toulouse University Hospital, place du Docteur-Baylac TSA 40031, 31059 Toulouse cedex 9, France; Paul Sabatier Toulouse III University, 31330 Toulouse, France; Inserm U1043 - CNRS UMR 5282, Toulouse-Purpan pathophysiology center, 31173 Toulouse cedex, France. Electronic address: