1. Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neonatology and NICU, Milan, Italy
2. University of Milan, Department of Clinical Sciences and Community Health, Milan, Italy
3. Fondazione IRCCS Policlinico San Matteo, Microbiology and Virology Department, Molecular Virology Unit, Pavia, Italy
4. ASST Papa Giovanni XXIII, Neonatology and NICU, Bergamo, Italy
5. Fondazione MBBM, S. Gerardo Hospital, Neonatology and NICU, Monza, Italy
6. Del Ponte Hospital, Neonatology and NICU, Varese, Italy
7. University of Insubria, Department of Pediatrics, Varese, Italy
8. Fondazione IRCCS Policlinico San Matteo, Neonatology and NICU, Pavia, Italy
9. Bolognini Hospital, Neonatology and NICU, Seriate, Italy
10. Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Microbiology and Virology Unit, Milan, Italy
11. University of Pavia. Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, Pavia, Italy