Epidemiological and virological assessment of influenza activity in Europe during the winter 2005-2006 Meijer, A and Meerhoff, T J and Meuwissen, L. E. and Van Der Velden, J and Paget, W J and European Influenza Surveillance Scheme (EISS), Eurosurveillance, 12, 733 (2007), https://doi.org/10.2807/esm.12.09.00733-en