1. Retrovirus Center and Virology Section, Department of Translational ResearchUniversity of Pisa Pisa Italy
2. Virology DivisionPisa University Hospital Pisa Italy
3. North‐Western Tuscany Blood BankPisa University Hospital Pisa Italy
4. Department of Molecular Medicine, Laboratory of Virology and Pasteur Institute‐Cenci Bolognetti FoundationSapienza University of Rome Rome Italy