2631. Influenza-Associated Intensive Care Unit Hospitalizations and Deaths in Children, During 2010–2019 in Greece

Abstract Background The clinico-epidemiological characteristics of children with severe influenza-related intensive care unit (ICU) admissions in Greece during 2010–2019 are described. Methods All laboratory-confirmed influenza cases (real-time PCR), in children 0–16 years old, admitted to Pediatric ICUs throughout the country, are reported using a mandatory notification system to the National Public Health Organization of Greece. Case fatality rates (CFR) were analyzed according to age and presence of comorbidities. Results From October 2010 to April 2019, 131 influenza cases [7.2/100,000 children, 65 (49.6%) girls] with PICUs admissions were recorded. The majority of cases (n = 78; 60%) occurred in the age group 0–4 years-old [31 (24%) children were < 12 months-old]. Sixty-five (49.6%) children had underlying comorbidities (22 neurological disease, 12 congenital syndromes, 7 cancer, 5 chronic respiratory, 19 other). The most common diagnosis was febrile ARDS and 67 (51.14%) had severe pneumonia (40% viral, 7% bacterial). Seventy-five (57.2%) children required invasive ventilation. Influenza A accounted for 102 (77.86%) of cases; out of 86 (84.31%) subtyped, 68 (79%) were AH1N1pdm09, and 18 (21%) were AH3N2. Influenza B accounted for 29 (22.13%) of cases. All children received oseltamivir. Median length of stay was 10 days (range 1–90). A total of 32 deaths was recorded (CFR 24.4%, total rate: 1.76/100,000 children); 13 (40.1%) deaths occurred in children with no known co-morbidity. Mortality rates were higher in children aged > 4 years (18/53, 33.9% vs. 14/78, 17.9%, P = 0.04) while there was a trend for children with comorbidities (19/65, 29.2% vs. 13/66, 19.69%, P = 0.1). Only 4% of children were previously immunized against influenza. Conclusion AH1N1pdm09 accounted for the vast majority of severe cases and influenza associated deaths in children in Greece over the last 10 years. Severe disease occurred also in children with no comorbitidies. Longitudinal clinico-epidemiological data should be considered in shaping the national immunization program. Disclosures All authors: No reported disclosures.