The Epidemiological and Economic Burden of Vaccine-Preventable Respiratory Diseases Among Adults Aged 65 Years and Older in the Nordic Countries.

Background: Despite the increasing availability of tailored vaccines, vaccine-preventable respiratory diseases (VPRDs), including influenza, respiratory syncytial virus (RSV), COVID-19, and pneumococcal disease (PD), continue to impose a significant health and economic burden. This study assessed the epidemiological and economic burden of VPRD among adults aged ≥65 across four Nordic countries (Denmark, Sweden, Norway, and Finland). Methods: Data on incidence, hospital admissions, and mortality were obtained from national statistics (week 21, 2024-week 20, 2025) and supplemented with peer-reviewed literature. A static model was developed to quantify epidemiological and economic burden associated with VPRD during the 2024/2025 winter season. Results: During the 2024/2025 season, VPRD resulted in approximately 830,000 symptomatic cases, 60,300 hospital admissions, and 7750 deaths across the Nordic countries. COVID-19 showed the highest estimated incidence and numbers of hospital admissions, followed by influenza, PD, and RSV. Mortality was comparable between COVID-19 and influenza, followed by PD and RSV. Annual healthcare costs were approximately €1132 million, with productivity losses constituting an additional 7%. Conclusions: Despite national vaccination efforts, VPRDs remain a major health and economic burden in the Nordic countries. Strengthening immunization programs through improved vaccine uptake, broader coverage, and use of advanced vaccines may contribute to further reducing this burden.