title: Influenza surveillance during the post-pandemic influenza 2010/11 season in Greece, 04 October 2010 to 22 May 2011.
abstract: In this manuscript, we summarise the experience of Greece during the post-pandemic influenza season 2010/11 from 04 October 2010 to 22 May 2011. The spread of the disease and its impact were monitored using multiple surveillance systems, such as sentinel surveillance, virological surveillance and all-cause mortality surveillance. We also focus on the characteristics of laboratory-confirmed severe influenza cases who required admission to an intensive care unit (ICU) (n=368), and/or with a fatal outcome (n=180). The influenza-like illness rate reported from sentinel surveillance started rising in early January 2011 and peaked between 31 January and 6 February 2011. The total number of ICU admissions was higher in the post-pandemic influenza season than during the pandemic period causing a lot of pressure on ICUs. The overall population mortality rate due to influenza A(H1N1)2009 was higher than during the pandemic period (15.9 vs 13.2 fatal cases per million, p=0.087). Our data suggest that the severity of clinical illness in the first post-pandemic influenza season was comparable or even higher than during the pandemic.
authors.affiliation: Hellenic Centre for Disease Control and Prevention, Athens, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Athanasiou
authors.forename: A
authors.initials: A
authors.lastname: Baka
authors.forename: A
authors.initials: A
authors.lastname: Andreopoulou
authors.forename: G
authors.initials: G
authors.lastname: Spala
authors.forename: K
authors.initials: K
authors.lastname: Karageorgou
authors.forename: L
authors.initials: L
authors.lastname: Kostopoulos
authors.forename: S
authors.initials: S
authors.lastname: Patrinos
authors.forename: T
authors.initials: T
authors.lastname: Sideroglou
authors.forename: E
authors.initials: E
authors.lastname: Triantafyllou
authors.forename: A
authors.initials: A
authors.lastname: Mentis
authors.forename: N
authors.initials: N
authors.lastname: Malisiovas
authors.forename: T
authors.initials: T
authors.lastname: Lytras
authors.forename: S
authors.initials: S
authors.lastname: Tsiodras
authors.forename: T
authors.initials: T
authors.lastname: Panagiotopoulos
authors.forename: S
authors.initials: S
authors.lastname: Bonovas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D006115:Greece / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000472:pathogenicity*; D007251:Influenza, Human / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy / Q000821:virology; D007362:Intensive Care Units / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D058873:Pandemics; D012621:Seasons; D018571:Sentinel Surveillance; D013997:Time Factors; D055815:Young Adult