Background: In 2003, the WHO aimed for a 75% or higher influenza vaccination rate among at-risk populations. However, this target was achieved in a few groups during selected seasons in some European countries, and never in Germany. Adults with underlying conditions (UCs) are a critical negleted group for influenza vaccination. This study aimed to identify data gaps in influenza burden and vaccination coverage among adults under 60 with UCs in Germany and bridge these gaps using real-world data.
Material and methods: We conducted systematic research and analyses using German administrative and claims databases from June 2016 to April 2024. We report on epidemiology, direct care costs, indirect costs from work incapacity, vaccination coverage rates, and describe data gaps.
Results: Influenza data for high-risk populations are limited. Comprehensive data on influenza epidemiology and vaccination coverage rates (VCR) is available, though with a delay in data availability. Before and after the pandemic, individuals aged 50-59 had the highest rates of influenza-related hospitalization and ICU admission compared to younger age groups. Across all age groups and seasons, individuals with UC experienced higher rates of medically attended influenza cases, hospitalizations, and healthcare costs, with those aged 35-59 being particularly vulnerable. Vaccine coverage was higher in adults aged 35-59 compared to those aged 18-24, and in females compared to males.
Limitations: Discrepancies of vaccination status, limited data availability, and variations among the extent of UCs.
Conclusion: In Germany, recent policy measures have mainly targeted those aged 60 and above. While this elderly population experiences the highest disease-related impact, influenza can also lead to substantial healthcare resource utilization (HCRU) and costs in younger populations with chronic UCs; Facilitating vaccination access for this group, such as through pharmacies, is essential. Definition of quantifiable vaccination targets and measures to increase vaccination rates based on these targets are required.
Keywords: I; I1; I10; I11; I19; Influenza in humans; adults; economics; germany; hospitalization; influenza vaccines; risk factors; vaccination coverage.
The research analysed real-world data on the impact of influenza among adults under 60 years old with underlying medical conditions in Germany. The key findings include: Low vaccination rates: The flu vaccination rate among adults with underlying conditions, such as asthma, diabetes, and heart disease, is low.High disease burden: This group has a significantly higher risk of severe influenza complications, experiencing notable rates of illness, hospitalization, and healthcare costs due to the flu. Given the high disease burden and low vaccine coverage, there is a need for improved public health strategies to increase flu vaccine access and uptake among this vulnerable population. These findings contribute to growing evidence supporting the importance of influenza vaccination for adults with underlying medical conditions. The insights provided can inform policymakers, healthcare providers, and public health officials working to improve vaccination rates and protect the health of these vulnerable populations.