Kissling, Esther, Valenciano, Marta, Pozo, Francisco, Vilcu, Ana-Maria, Reuss, Annicka, Rizzo, Caterina, Larrauri, Amparo, Horváth, Judit Krisztina, Brytting, Mia, Domegan, Lisa, Korczyńska, Monika, Meijer, Adam, Machado, Ausenda, Ivanciuc, Alina, Višekruna Vučina, Vesna, van der Werf, Sylvie, Schweiger, Brunhilde, Bella, Antonino, Gherasim, Alin, Ferenczi, Annamária, Zakikhany, Katherina, O'Donnell, Joan, Paradowska-Stankiewicz, Iwona, Dijkstra, Frederika, Guiomar, Raquel, Lazar, Mihaela, Kurečić Filipović, Sanja, Johansen, Kari, Moren, Alain, I-MOVE/I-MOVE+ study team, EpiConcept [Paris], National Centre for Microbiology [Madrid], Instituto de Salud Carlos III [Madrid] (ISC), Institut Pierre Louis d'Epidémiologie et de Santé Publique (iPLESP), Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Sorbonne Université (SU), Department for Infectious Disease Epidemiology [Berlin], Robert Koch Institute [Berlin] (RKI), Department of Infectious Diseases [Rome, Italy], Istituto Superiore di Sanita, CIBER de Epidemiología y Salud Pública (CIBERESP), National Centre for Epidemiology. CIBERNED. Carlos III Institute of Health, Madrid, Centro de Investigacion Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III [Madrid] (ISC)-Instituto de Salud Carlos III [Madrid] (ISC), National Centre for Epidemiology [Budapest], Public Health Agency of Sweden, Health Protection Surveillance Centre (HPSC), National Institute of Public Health - National Institute of Hygiene [Poland], National Institute for Public Health and the Environment [Bilthoven] (RIVM), Instituto Nacional de Saùde Dr Ricardo Jorge [Portugal] (INSA), Cantacuzino Institute [Romania], Réseau International des Instituts Pasteur (RIIP), Croatian Institute of Public Health [Zagreb] (CIPH), Génétique moléculaire des virus à ARN ((U-Pasteur_ 2 / UMR_3569)), Institut Pasteur [Paris]-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), National Reference Centre for Influenza [Berlin], European Centre for Disease Prevention and Control (ECDC), Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU), Istituto Superiore di Sanità (ISS), Génétique Moléculaire des Virus à ARN - Molecular Genetics of RNA Viruses (GMV-ARN (UMR_3569 / U-Pasteur_2)), Institut Pasteur [Paris] (IP)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), European Centre for Disease Prevention and Control [Stockholm, Sweden] (ECDC), Instituto de Salud Carlos III (ISC), CIBER de Enfermedades Neurodegenerativas (CIBERNED), National Institute of Public Health – National Institute of Hygiene [Varsovie], Instituto Nacional de Saúde Doutor Ricardo Jorge [Lisboa], European Centre for Disease Prevention and Control, Kissling, Esther, Valenciano, Marta, Pozo, Francisco, Vilcu, Ana-Maria, Reuss, Annicka, Rizzo, Caterina, Larrauri, Amparo, Horváth, Judit Krisztina, Brytting, Mia, Domegan, Lisa, Korczyńska, Monika, Meijer, Adam, Machado, Ausenda, Ivanciuc, Alina, Višekruna Vučina, Vesna, van der Werf, Sylvie, Schweiger, Brunhilde, Bella, Antonino, Gherasim, Alin, Ferenczi, Annamária, Zakikhany, Katherina, O Donnell, Joan, Paradowska-Stankiewicz, Iwona, Dijkstra, Frederika, Guiomar, Raquel, Lazar, Mihaela, Kurečić Filipović, Sanja, Johansen, Kari, Moren, Alain, and D'Agaro, Pierlanfranco