Data on influenza-like illness were collected through cross-sectional nationwide telephone surveys of 1,000 households in Greece repeated for 25 consecutive weeks (2009-2010) and were combined with data from H1N1 virologic surveillance to estimate the incidence and the clinical attack rate of influenza A(H1N1). Data on H1N1 morbidity and mortality were used to estimate ICU admission and case fatality (CFR) rates.
