The Potential Global Health Impact and Cost-effectiveness of Next-generation Influenza Vaccines: A Modelling Analysis
Lucy Goodfellow, Simon R Procter, Mihaly Koltai, Naomi R. Waterlow, Johnny A. N. Filipe, Carlos K. H. Wong, Edwin van Leeuwen, Rosalind M. Eggo, Mark Jit.
Abstract
Next-generation influenza vaccines (NGIVs) are in development and have the potential to achieve substantial reductions in influenza burden, with resulting widespread health and economic benefits. The prices at which their market can be sustained and which vaccination strategies may maximise health impact and cost-effectiveness, particularly in low- and middle-income countries, are unknown, yet such an understanding could provide a valuable tool for vaccine development and investment decision-making at a national and global level. To address this evidence gap, we projected the health and economic impact of NGIVs in 186 countries and territories.
Introduction
Globally, seasonal influenza is a substantial cause of respiratory illness, morbidity, and mortality, causing 291,243–645,832 deaths annually and significant economic impact through healthcare costs, costs to the individual, and productivity losses. The burden varies between countries and wider geographical regions, due to variation in circulating influenza strains and subtypes, population age structure, and current vaccination programmes and coverage. Furthermore, the timing and regularity of influenza epidemics ranges widely around the world, as does the quality and reliability of influenza surveillance data.
Materials and Methods:
We used a modelling framework consisting of four steps (Fig 1A) to assess the future impact and cost-effectiveness of NGIVs in 186 countries and territories (hereafter referred to as just countries). The steps were: (1) epidemiological inference model (infer current influenza transmission parameters in regions with similar transmission dynamics), (2) vaccination model (project age- and vaccination status-specific populations in each country), (3) epidemic model (simulate future influenza epidemics), and (4) economic model (estimate cost-effectiveness).
Discussion
We found that using NGIVs could have a dramatic impact on global influenza burden and be cost-effective in some parts of the world even if prices are higher than most other vaccines in the routinely recommended schedule, however affordability is likely to be a barrier to adoption in lower income countries based on WTP thresholds calculated from the efficiency of current health expenditure in countries. Vaccinating children aged under 18 years old with currently licensed vaccines could prevent 37% of influenza infections (1.33 billion infections) when compared to no influenza vaccinations; this increased to 53% using minimally improved vaccines and 83% using universal vaccines.
Acknowledgments
WHO Technical Advisory Group for the Full Value of Influenza Vaccines Assessment and project team: WHO FVIVA Technical Advisory Group members: Jon Abramson, Salah Al Awaidy, Silvia Bino, Rebecca Jane Cox, Luzhao Feng, Jodie McVernon, Harish Nair, Anthony T Newall, Punnee Pitisuttithum. WHO FVIVA project team members: Philipp Lambach, Mitsuki Koh, Joseph Bresee, Stefano Malvolti, Carsten Mantel, Sara Sá Silva, Adam Soble, Carlo Federici. Next-generation influenza vaccine impact modelling contributors: Paula Barbosa, Shawn Gilchrist, Dafrossa Lyimo, Rajinder Suri, Joseph T Wu. We also thank Eduardo Azziz-Baumgartner and Kathryn Lafond for helpful discussions. Two members of WHO FVIVA project team work for the World Health Organisation (PL and MK). The authors alone are responsible for the views expressed in this publication and they do not necessarily represent the decisions, policy or views of the World Health Organisation.
Citation: Goodfellow L, Procter SR, Koltai M, Waterlow NR, Filipe JAN, Wong CKH, et al. (2025) The potential global health impact and cost-effectiveness of next-generation influenza vaccines: A modelling analysis. PLoS Med 22(6): e1004655. https://doi.org/10.1371/journal.pmed.1004655
Editor: Rebecca F. Grais, Pasteur Network, FRANCE
Received: September 17, 2024; Accepted: June 3, 2025; Published: June 30, 2025.
Copyright: © 2025 Goodfellow et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All input data is from publicly available sources and can be found at at https://doi.org/10.5281/zenodo.15535351.
Funding: LG, SRP, NRW, RME and MJ were funded through the Task Force for Global Health (grant numbers INF-CDC-R2R; INF-CDC-PV3, INF-CDC-PV4, www.taskforce.org) in collaboration with Partnership for Influenza Vaccine Introduction (PIVI, www.pivipartners.org), Ready2Respond (www.ready2respond.org), Wellcome Trust (www.wellcome.org), Centers for Disease Control and Prevention (CDC, www.cdc.gov), and by the World Health Organization (grant number 2305-IAI-PDR-Flu-Vac, www.who.int). JF and CW were funded by AIR@InnoHK administered by Innovation and Technology Commission, Government of Hong Kong Special Administrative Region, China, as part of the Laboratory of Data Discovery for Health (D24H, www.d24h.hk). EvL, RME, and MJ were also supported by the National Institute for Health Research (NIHR) Health Protection Research Unit (HPRU) in Modelling and Health Economics, a partnership between UKHSA, Imperial College London, and LSHTM (grant number NIHR200908, www.nihr.ac.uk). The views expressed are those of the authors and not necessarily those of the UK Department of Health and Social Care (DHSC), NIHR, or UKHSA. The funders had no other role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
