1. Departments of Paediatrics; University of Crete; Heraklion Greece
2. Department of Microbiology; Heraklion University Hospital; Heraklion Greece
3. Infectious Diseases Research Laboratory; 4th Department of Internal Medicine; National and Kapodistrian University of Athens; Athens Greece
4. Department of Paediatrics; Democritus University of Thrace; Alexandroupolis Greece
5. Department of Internal Medicine; University of Crete; Heraklion Greece