1995. Severe Influenza; Greece 2016-2017: Vaccine Failures in Type A Influenza and Risk Factors for Poor Outcome
Session: Poster Abstract Session: Clinical: Respiratory Track
Saturday, October 7, 2017
Room: Poster Hall CD

We examined risk factors for influenza related death in severe cases in Greece during the 2016-17 influenza season. We also analyzed influenza vaccination data in this severely affected patient cohort.


A national severe influenza surveillance system supported by the Hellenic CDC monitors all laboratory-confirmed influenza cases admitted to ICU &/or in-hospital deaths of influenza patients. Each case is followed up daily, with a structured questionnaire until discharged from the hospital. We evaluated risk factors for death using univariate & multivariate analyses.


A total of 288 cases were recorded until week 18/2016 (median age 72 yrs, 63.2% male, 89.9% high risk pts with comorbidities for whom flu immunization was indicated). 24.7% of severe influenza cases were reported as obese (BMI>30 kg/m2). Influenza A was noted in 86.5% with AH3N2 typed in 99.9 % of cases. AH3N2 influenza was noted in older individuals compared to B influenza (mean age 68 yrs vs 55.5 yrs respectively, p<0.01). 108/279 (37.5%) deaths were recorded (median age 74.5 yrs, 45.7% male, 9 pts still hospitalized in week 18th2017). In multivariate analyses, risk factors for death were: presence of ARDS [OR: 2.1; 95%CI 1-4.6, p=0.05], presence of multi-organ dysfunction (MODS) [OR: 25.4; 95%CI 7.9-81.4, p<0.001, adjusting for concomitant ARDS], and the presence of an immunocompromising condition [OR: 2; 95% CI 1-4.2, p=0.05]. Intubated patients, with severe influenza, awaiting ICU bed placement, had significantly poorer outcomes (OR for death 2.6; 95%CI 2.1-3.2, p<0.001). 63/231 (27.2%) of cases with available data reported vaccination with the seasonal vaccine. Vaccination did not protect against MODS (OR: .99; 95%CI .7-1.5, p=1) or death (OR: 1.04; 95%CI .8-1.2, p=0.9). Among influenza A affected pts, 58/203 (28.6%) were vaccinated compared to 5/28 (17.9%) pts with B influenza (chi-square 1.4, p=0.2).


ARDS, MODS and the presence of an immune compromising condition were risk factors for death in a AH3N2 predominant season in Greece. Vaccination failures were most frequently noted in type A influenza affected patients. Vaccination did not protect against MODS or death in this severe influenza cohort. Surge capacity issues and hospitalization outside the ICU was associated with a higher risk for death.

Theodore Lytras, MD, MPH1, Agoritsa Baka, MD1, Anastasia Andreopoulou, MSc1, Elisavet Mouratidou, RN, MSc1, Ourania Kalkouni, MD1, Theano Georgakopoulou, MD, MPH, PhD1 and Sotirios Tsiodras, MD, MSc, PhD, FIDSA2,3, (1)Hellenic Center for Disease Control and Prevention, Athens, Greece, (2)4th Department of Internal Medicine, University General Hospital Attikon, National and Kapodistrian University of Athens Medical School, Athens, Greece, (3)4th Department of Internal Med., Med. Sch. of Natl. and Kapodistrian Univ. of Athens, “Attikon” Univ. Hosp., Athens, Greece


T. Lytras, None

A. Baka, None

A. Andreopoulou, None

E. Mouratidou, None

O. Kalkouni, None

T. Georgakopoulou, None

S. Tsiodras, None

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