1. Leto General, Maternity & Gynecology Clinic, 11524 Athens, Greece
2. Department of Microbiology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
3. School of Medicine, University of Patras, 26504 Rio, Greece
4. Department of Medicine and Research Laboratory of Internal Medicine, General University Hospital of Larissa, 41110 Larissa, Greece
5. Laiko General Hospital of Athens and Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
6. Department of Internal Medicine and Infectious Diseases, University General Hospital of Patras, 26504 Rio, Greece