Influenza surveillance during the post-pandemic influenza 2010/11 season in Greece, 04 October 2010 to 22 May 2011.

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.

Factors influencing influenza vaccination rates among healthcare workers in Greek hospitals.

Influenza vaccination rates are generally low among healthcare workers (HCWs) worldwide. In September 2005, the Hellenic Center for Disease Control and Prevention conducted a nationwide campaign to promote influenza vaccination in hospital HCWs. During the 2005-2006 influenza season, the overall vaccination rate among HCWs was 16.36% (range: 0-85.96%). The self-reported vaccination rate during the previous season was 1.72%, indicating a 9.5-fold increase. Compared with physicians, significantly fewer technical personnel were vaccinated, whereas administrative personnel were more likely to receive the vaccine. Among clinicians, rates for internal medicine departments exceeded those of surgical departments by a factor of 2.71 and laboratory medicine departments by a factor of 2.36. Multivariate analysis showed lower vaccination rates in large hospitals (>200 beds) than in smaller hospitals and lower rates in hospitals with specialist services (intensive care unit, psychiatry or dermatology) than in general hospitals. Factors associated with higher rates included working in northern Greece, in a paediatric or an oncology hospital, or in a prefecture with avian influenza H5N1 activity. In conclusion, in Greece influenza vaccination rates among HCWs remain low, but the implementation of a nationwide campaign had a considerable impact. Efforts should focus on hospital- and HCW-associated factors to increase vaccination uptake.