Influenza is responsible for considerable health and economic burden every year. Especially older adults are vulnerable for influenza infection and its complications due to immunosenescence and often-underlying medical conditions. Recently, the innovative quadrivalent high-dose influenza vaccine (QIV-HD) has become available in Europe. Through its enhanced immunogenicity, QIV-HD offers improved protection for older adults against respiratory as well as cardiovascular complications. We estimated the potential impact—specifically in terms of hospital admissions and related costs—of a hypothetical past switch from QIV-Standard dose (SD) to QIV-HD in The Netherlands.
Estimates of hospitalizations for the older adults vaccinated with QIV-SD were derived from the seasons 2010/2011-2017/2018. Subsequently, the number of respiratory infections and cardiovascular complications of influenza were estimated for the year 2019/2020 for both QIV-SD and QIV-HD. To calculate the overall corresponding savings, costs for hospital complications, derived from literature, were used.
When QIV-HD would have been used instead of QIV-SD during the season 2019/2020, an additional 220 hospitalizations would have been averted among older adults of 60 years and older in the Netherlands. This corresponds to savings of €1 219 779 (uncertainty interval: 1 089 813-1 348 549), of which 69% is attributable to cardiovascular-related hospitalizations.
We demonstrate that a relevant improvement in influenza vaccination among older adults in The Netherlands can be achieved by switching from the current QIV-SD to QIV-HD. Not only comes a switch from QIV-SD to QIV-HD with a significant reduction in pressure on hospital capacity but also with notable cost savings.