640. Severe influenza cases in season 2015-2016, Greece: surveillance and risk factors for poor outcome
Session: Poster Abstract Session: Oh, Those Pesky Viruses!
Thursday, October 27, 2016
Room: Poster Hall
Background: We examined risk factors for influenza related death in severe cases reported in Greece during the 2015-16 influenza season.

Methods: A national severe influenza surveillance system supported by the Hellenic Ctr for Disease Control & Prevention (HCDCP) monitors all laboratory-confirmed influenza cases admitted to Intensive Care Unit (ICU) &/or in-hospital deaths of influenza patients. Each case is followed up daily, with a structured questionnaire until discharged. We evaluated risk factors for death using univariate & multivariate analyses.

Results:A total of 434 cases were recorded until week 20/2016 (median age 58 yrs, 59.2% male, 77.2% high risk pts with comorbidities); the highest number ever in the six years of the system function since 2009. 36.6% of severe influenza cases were reported as obese (BMI>30), and 14% were morbidly obese. Only 25/274 (9%) of cases with available data reported vaccination with the seasonal influenza vaccine. Influenza A was diagnosed in 98.2% of cases. 196/426 (46%) deaths are recorded in available data (median age 57yrs, 45.7% male). In 98% of deaths, influenza A was diagnosed [A(H1N1)pdm09: 86.2%, untyped A: 10.2%]. 144/426 (33.8%) deaths occurred in patients with immunization indications. In multivariate analyses risk factors for death were: presence of ARDS [OR 2.3, 95%CI 1.5-3.8 p<0.001], history of cardiovascular disease [OR 1.9, 95%CI 1.2-3, p=0.006] and the presence of malignancy [OR 2.3, 95% CI 1.2-4.5 p=0.01]. Patients without underlying diseases had a higher chance of survival (OR 0.49 95% CI 0.29-.82, p =0.008). Intubated patients with severe influenza awaiting ICU bed had significantly poorer outcomes (OR for death 16.9; 95%CI 3.9-72, p=0.001).

Conclusion: ARDS, malignancy, cardiovascular disease and delay in ICU admission were risk factors for death in an A/H1N1pdm09 predominant season in Greece. Vaccination compliance remained very low in highly susceptible individuals. A preponderance of obese individuals were affected. Surge capacity issues and hospitalization outside the ICU was associated with a higher risk for death

Agoritsa Baka, MD1, Anastasia Andreopoulou, MSc2, Elisavet Mouratidou, RN, MSc3, Georgia Spala, MD4, Theodore Lytras, MD, MPH5, Ourania Kalkouni, MD2, Stavroula Koukouli, BSc5, Eirini Velioti, BSc5, Theano Georgakopoulou, MD, MPH, PhD5, Christos Hadjichristodoulou, MD, MPH, PhD6 and Sotirios Tsiodras, MD, PhD7,8, (1)Hellenic Ctr for Disease Control & Prevention (HCDCP), Marousi, Greece, (2)Epidemiology and Intervention, Hellenic Centre for Disease Control and Prevention, Marousi, Greece, (3)Hellenic Centre for Disease Control and Prevention (HCDCP), Marousi, Greece, (4)Epidemiology and Intervention, Hellenic Center for Disease Control and Prevention, Marousi, Greece, (5)Epidemiology Surveillance and Response, Hellenic Centre for Disease Control and Prevention (HCDCP), Marousi, Greece, (6)Dept of Hygiene and Epidemiology, University of Thessaly, Larissa, Greece, (7)4th Department of Internal Medicine, University General Hospital Attikon, National and Kapodistrian University of Athens Medical School, Athens, Greece, (8)Office for Scientific Advice, Hellenic Center for Disease Control and Prevention, Marousi, Athens, Greece


A. Baka, None

A. Andreopoulou, None

E. Mouratidou, None

G. Spala, None

T. Lytras, None

O. Kalkouni, None

S. Koukouli, None

E. Velioti, None

T. Georgakopoulou, None

C. Hadjichristodoulou, None

S. Tsiodras, None

Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.