1 Epidemiology Unit, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid, Madrid, Spain. [email protected].
2 Institute of Medical Microbiology and Hygiene, Saarland University, Homburg/Saar, Germany.
3 Université Paris Cité, Inserm, CIC 1417, F-CRIN, Innovative clinical research network in vaccinology (I-REIVAC), and Assistance Publique-Hôpitaux de Paris, CIC Cochin Pasteur, Hôpital Cochin, Paris, France.
4 Travel Medicine Department, National Public Health Organization, Athens, Greece.