SONIA PEREZ CASTRO, Amparo Larrauri, Catherine Moore, Sylvie Van der WERF, Nuria Torner, Pedro Pechirra, FALCHI Alessandra, Bruno Lina, Lisa Domegan, Cathriona Kearns, Thea Kølsen Fischer, Maria Concepcion Delgado Sanz, Francisco Pozo, Simon De Lusignan, Lidia Brydak, Santiago Melón García, Ramona Trebbien, Inmaculada Casas, Richard Pebody, Silvia Jiménez-Jorge, European Centre for Disease Prevention and Control [Stockholm, Sweden] (ECDC), University of Turku, Turku University Hospital (TYKS), 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), Centre National de Référence des virus des infections respiratoires (dont la grippe) - National Reference Center Virus Influenzae [Paris] (CNR - laboratoire coordonnateur), Institut Pasteur [Paris] (IP)-Université Paris Cité (UPCité), Specific country acknowledgements Denmark: For Denmark the test results for respiratory syncytial virus in the season 2015/16 were obtained from the Danish Microbiology Database (MiBa, http://miba.ssi.dk), which contains all electronic reports from departments of clinical microbiology in Denmark since 2010, and we acknowledge the collaboration with the MiBa Board of Representatives. France: For primary care, sentinel networks: all GPs, paediatricians and their patients for providing the samples tested. For the hospital laboratory network, RENAL: Ile de France, - Ambroise Pare, Avicenne, Bichat, Bicêtre, Henri Mondor, Versailles, Necker, Paul Brousse, Pitie Salpetrière, Robert Debré, Saint-Louis, Cochin, Trousseau-Saint Antoine-Tenon, Pontoise, Poissy and Foch. Other regions: Strasbourg, Dijon, Reims, Nancy, Besançon, Lille, Amiens, Caen, Brest, Rennes, Orléans, Tours, Rouen, Angers, Nantes, Aix-en-Provence, Annecy, Bordeaux, Chambéry, Clermont-Ferrand, Grenoble, Limoges, Lyon, Marseille, Montpellier, Nice, Poitiers, Saint-Etienne and Toulouse. Hôpitaux Militaires: HIA Begin – Dr A. MERENS, HIA Legouest – Dr Y. ROBERT, HIA Clermont Tonnerre – Dr P. LE GUEN, Hôpitaux Militaires: Bordeaux – Lyon - Marseille – Toulon. Ireland: We would like to acknowledge the Irish sentinel GP network, hospital clinicians and clinical microbiologists for taking and providing specimens to the National Virus Reference Laboratory (NVRL) for RSV testing. Latvia: Laboratory specialists A.Aniščenko, T. Kolupajeva, for performing virological analyses. The Netherlands: GPs and their patients for taking and providing specimens, clinical microbiologists from diagnostic laboratories for providing weekly diagnostics virological reports, technicians in the laboratories for performing virological analyses. Poland: All members of NIC in Poland working in years 2010-2016, Voivodship Sanitary Epidemiological Stations in Poland. Portugal: We acknowledge the Colleagues from the National Institute of Health Dr Ricardo Jorge, I.P. that contributed to the supported of the National Influenza Surveillance Program. We acknowledge to the Portuguese GP Sentinel Network, to physicians from Emergency and Obstetric Units Network, to physicians of the EuroEva project and to the Portuguese Laboratory Network for Influenza Diagnosis. Spain: We would like to acknowledge all the professionals participating in the Spanish Influenza Surveillance System. Sweden: Contributing laboratories and paediatric clinics., We express our gratitude to the European Surveillance System data management team, especially Marius Valentin Valcu, Adrian Prodan and Cátia Cunha. We thank Silviu Lucian Ionescu for calculation of barycentres. We thank Cornelia Adlhoch for supporting the data collection for RSV within TESSy. We are grateful to Tommi Kärki for the support with preparation of Figure 2. We would also like to thank Julien Beauté, Phillip Zucs and Mike Catchpole for their valuable comments. We acknowledge all the members of the European Influenza Surveillance Network for their tireless work for influenza surveillance in European Union/European Economic Area countries and for testing for RSV and including the RSV detections in the weekly reporting., European Influenza Surveillance Network members from the contributing countries Denmark: Ramona Trebbien, Hanne-Dorthe Emborg, Tyra Grove Krause and Thea K Fischer (Statens Serum Institut, Copenhagen). Estonia: Natalja Kuznetsova, Liidia Dotsenko (Estonian Health Board, Laboratory of Communicable Diseases, Tallinn) and Olga Sadikova (Estonian Health Board, Department of CD surveillance and control, Influenza Centre, Tallinn). France: Sylvie Behillil (Unité de Génétique Moléculaire des Virus à ARN, UMR 3569 CNRS, Université Paris Diderot SPC, Institut Pasteur, Paris, CNR des Virus Influenzae, Institut Pasteur, Paris), Thierry Blanchon (Sorbonne Université, INSERM, Institut Pierre Louis d’Epidémiologie et de Santé Publique (IPLESP), F75012 Paris, France), Lisandru Capai (Sorbonne Université, INSERM, Institut Pierre Louis d’Epidémiologie et de Santé Publique (IPLESP), F75012 Paris, France), F75012, Paris, EA7310, Laboratoire de Virologie, Université de Corse-Inserm, Corte), Jean-Marie Cohen (Open Rome (Organize and Promote Epidemiological Network), Paris, France, Réseau des GROG, Paris), Vincent Enouf (Unité de Génétique Moléculaire des Virus à ARN, UMR 3569 CNRS, Université Paris Diderot SPC, Institut Pasteur, Paris, CNR des Virus Influenzae, Institut Pasteur, Paris), Alessandra Falchi (EA7310, Laboratoire de Virologie, Université de Corse-Inserm, Corte), Caroline Guerrisi (Sorbonne Université, INSERM, Institut Pierre Louis d’Epidémiologie et de Santé Publique (IPLESP), F75012 Paris, France), Bruno Lina (Laboratoire de Virologie, CNR des virus influenza, Institut des Agents Infectieux, Groupement Hospitalier Nord des HCL, Lyon, Laboratoire Virpath, CIRI Inserm U1111, CNRS 5308, ENS, UCBL, Faculté de Médecine LYON Est, Université de Lyon, Lyon), Thomas Hanslik (AP-HP, Hôpital Ambroise Paré, Service de Médecine interne, F-92100 Boulogne Billancourt, France), Shirley Masse (Sorbonne Université, INSERM, Institut Pierre Louis d’Epidémiologie et de Santé Publique (IPLESP), F75012 Paris, France, EA7310, Laboratoire de Virologie, Université de Corse-Inserm, Corte), Anne Mosnier (Open Rome (Organize and Promote Epidemiological Network), Paris, France, Réseau des GROG, Paris), Clément Turbelin (Sorbonne Université, INSERM, Institut Pierre Louis d’Epidémiologie et de Santé Publique (IPLESP), F75012 Paris, France), Martine Valette (Laboratoire de Virologie, CNR des virus influenza, Institut des Agents Infectieux, Groupement Hospitalier Nord des HCL, Lyon, Laboratoire Virpath, CIRI Inserm U1111, CNRS 5308, ENS, UCBL, Faculté de Médecine LYON Est, Université de Lyon, Lyon), Sylvie van der Werf (Unité de Génétique Moléculaire des Virus à ARN, UMR 3569 CNRS, Université Paris Diderot SPC, Institut Pasteur, Paris, CNR des Virus Influenzae, Institut Pasteur, Paris). Germany: Brunhilde Schweiger, Janine Reiche, Barbara Biere (National Influenza Centre, Robert Koch Institute, Berlin) and Silke Buda (Respiratory Infections Unit, Department for Infectious Disease Epidemiology, Robert Koch Institute, Berlin). Iceland: Gudrun Erna Baldvinsdottir (Department of Clinical Microbiology at Landspitali University Hospital, Reykjavik). Ireland: Lisa Domegan and Joan O Donnell (HSE-Health Protection Surveillance Centre, Dublin), Christina Byrne, Paul O’Reilly, Joanne Moran, Allison Waters and Cillian de Gascun (National Virus Reference Laboratory, University College Dublin, Dublin). Latvia: Natalija Zamjatina and Gatis Pakarna (Riga East University Hospital, Latvian Centre of Infectious Diseases, Riga) and Raina Nikiforova (Centre for Disease Prevention and Control, Riga). Malta: Jackie Maistre Melillo and Tanya Melillo (Infectious Disease Prevention and Control Unit, Msida). The Netherlands: Adam Meijer (Centre for Infectious Diseases Research, Diagnostics and Laboratory Surveillance, National Institute for Public Health and the Environment (RIVM), Bilthoven), Anne Teirlinck (Centre for Infectious Diseases, Epidemiology and Surveillance, RIVM) and Gé Donker (NIVEL, Netherlands Institute for Health Services Research, Utrecht). Poland: Lidia B. Brydak and Katarzyna Cieślak (National Influenza Centre, Department of Influenza Research, National Institute of Public Health - National Institute of Hygiene, Warsaw). Portugal: Raquel Guiomar, Paula Cristóvão and Pedro Pechirra (National Influenza Reference Laboratory, Infectious Diseases Department, National Institute of Health Dr Ricardo Jorge, I.P., Lisbon) and Ana Paula Rodrigues (Department of Epidemiology, National Institute of Health Dr Ricardo Jorge, I.P., Lisbon). Slovenia: Katarina Prosenc (National Laboratory for Health, Environment and Food, Slovenia) and Maja Socan (Public Health Institute, Slovenia). Spain: Amparo Larrauri, Concepcion Delgado-Sanz, Jesús Oliva, (National Centre of Epidemiology, CIBERESP, Instituto de Salud Carlos III, Madrid), Silvia Jiménez-Jorge (National Centre of Epidemiology, Instituto de Salud Carlos III, Madrid), Francisco Pozo, Inmaculada Casas (National Centre of Microbiology, Instituto de Salud Carlos III, Madrid), Jose María Navarro (Hospital Virgen de las Nieves de Granada), Virtudes Gallardo (Consejería de Salud, Andalucía), Manuel Omeñaca (HU Miguel Servet), Elisa Marco (Dirección General de Salud Pública, Aragón), Santiago Melón (HU Central de Asturias), Ismael Huerta (Dirección General de Salud Pública, Asturias), Jordi Reina (Hospital Son Espases de Palma de Mallorca), Carmen Pérez González (Hospital Dr Negrín de Las Palmas de Gran Canarias), Lucas González (Dirección General de Salud Pública, Canarias), Microbiologists of the Hospital Network of Castilla La Mancha, Maria Victoria García Rivera (Servicio de Epidemiología, Consejería de Sanidad), Raúl Ortiz de Lejarazu (National Influenza Center, Hospital Clínico Universitario Valladolid), Tomás Vega (Observatorio de Salud Pública, Castilla y León), Mª Ángeles Marcos (Hospital Clínico de Barcelona), Nuria Torner (Agència de Salut Pública, CIBERESP, Cataluña), Sonia Perez Castro (CH Meixoeiro, Vigo), Juan Garcia Costa (CH Santa María Nai, Ourense), María Jesús Purriños (Dirección Xeral Saúde Pública, Galicia), Antonio Moreno Docón (Hospital Virgen de la Arrixaca), Miriam Fernández (Clínica Universitaria de Navarra), Carmen Ezpeleta (Complejo Hospitalario de Navarra), Jesús Castilla (Instituto de Salud Pública, CIBERESP, Navarra), Miriam Blasco (Hospital de La Rioja de Logroño), Carmen Quiñones (Dirección General de Salud Pública y Consumo, La Rioja), José López Barba (Hospital de INGESA), Ana Rivas (Consejería de Sanidad y Bienestar Social, Ceuta). Sweden: AnnaSara Carnahan, Sarah Axelsson, Hélène Englund, Marie Rapp and Mia Brytting (Public Health Agency of Sweden, Stockholm). United Kingdom: Richard Pebody (PHE, Colindale), Joanna Ellis (PHE, Colindale), and Maria Zambon (PHE, Colindale), Simon de Lusignan (Royal College of General Practitioners, London), Naomh Gallagher, Chris Nugent and Cathriona Kearns (Public Health Agency, Northern Ireland), Simon Cottrell and Catherine Moore (Public Health Wales, Cardiff), Jim McMenamin (HPS, Glasgow).