1. Department of Microbiology, Medical School, University of Athens, Athens, Greece
2. Department of Microbiology, Saint Panteleimon General Hospital, Nicea, Greece
3. Neonatal Intensive Care Unit, Saint Panteleimon General Hospital, Nicea, Greece
4. Department of Medical Microbiology, University Medical Centre Groningen, Rijksuniversiteit Groningen, The Netherlands