Burden of influenza in Germany: a retrospective claims database analysis for the influenza season 2012/2013

OBJECTIVE: Seasonal influenza occurs in annual epidemics. The virus can cause severe illness and concomitant diseases with the highest risk for children, the elderly, and individuals with disease dispositions. The study objective is to assess the influenza burden in Germany. METHODS: This retrospective claims data analysis used the Health Risk Institute research database containing anonymized data of 4 million individuals. The study period comprised the influenza season 2012/2013 in which patients with documented influenza were identified. Disease frequency rates were calculated for a population with disease dispositions and a population not at high risk. Disease burden was assessed based on health-services utilization during the influenza season. Vaccine rates were calculated by identifying vaccinations. RESULTS: We observed 65,826 patients with influenza, resulting in 1,160,646 documented influenza cases after extrapolation. Overall, otitis media and pneumonia was higher in the influenza-infected population compared to the non-influenza-infected population and especially high in children. Hospitalization cost amounted to €87,202,485 with a mean stay of 7 days, and total outpatient costs were €14,947,976. Vaccination rates were <4 % for children and 37 % for patients aged >60. CONCLUSIONS: Seasonal influenza can cause severe outcomes with hospitalizations and excess costs. Especially influenza-infected children are affected by concomitant diseases with higher disease burden. Furthermore, documented vaccination rates are quite low.