According to a recent assessment by the World Health Organization (WHO), next-generation influenza vaccines that offer broader and longer-lasting protection than current seasonal formulations could significantly reduce the worldwide impact of influenza.

The new WHO Full Value of Improved Influenza Vaccine Assessment (FVIVA), published alongside an article in the journal Vaccine, examines the public health, economic, and policy implications of next-generation influenza vaccines. It also outlines potential barriers to their global adoption. Together, these analyses provide evidence to inform investment decisions, shape policies, and guide introduction strategies—strengthening seasonal influenza programmes while reinforcing pandemic preparedness efforts.

Globally, seasonal influenza causes about one billion infections each year. Of these, an estimated 3 to 5 million cases result in severe illness, and between 290,000 and 650,000 deaths occur due to respiratory complications.

Although existing influenza vaccines reduce disease burden, their effectiveness varies depending on the season, the product used, and the population receiving it. Protection generally lasts for only one season. Twice annually, WHO convenes experts from the Global Influenza Surveillance and Response System to recommend the viral strains to be included in upcoming vaccines. While 143 countries report having seasonal influenza vaccines available, most doses are used in upper-middle- and high-income countries.

The FVIVA estimates that if improved, next-generation, or universal influenza vaccines become available and widely used between 2025 and 2050, they could prevent up to 18 billion influenza cases and save as many as 6.2 million lives worldwide. The greatest benefits would likely be seen among groups at higher risk of severe disease, including older adults, young children, and pregnant women.

“This assessment highlights the wide-ranging advantages that enhanced influenza vaccines could deliver across diverse settings,” said Dr Philipp Lambach, WHO technical lead for the project. “It offers a shared evidence base for stakeholders involved in vaccine investment, policy development, and research, helping to accelerate progress in vaccine innovation.”

The findings further indicate that in many countries, next-generation influenza vaccines could remain cost-effective or even generate cost savings. In addition, higher vaccine uptake contributes to lower antimicrobial use. Current influenza vaccination is estimated to prevent around 10 million unnecessary antibiotic doses each year. Between 2025 and 2050, improved influenza vaccines could avert up to 1.3 billion defined daily doses of antibiotics, making a substantial contribution to global efforts to combat antimicrobial resistance.

The overall impact of enhanced influenza vaccines will vary depending on national circumstances, including disease burden, health system capacity, vaccine pricing, and programme delivery considerations. Factors such as safety, effectiveness, duration of protection, temperature stability, and shelf life will also play a key role in adoption decisions, particularly in low- and middle-income countries.

The Full Value of Vaccine Assessment framework is intended to promote informed dialogue among governments, researchers, manufacturers, and partners. It offers a comprehensive overview of the potential benefits of improved vaccines, as well as the scientific, economic, and practical considerations linked to their development and implementation.

The FVIVA supports WHO’s Global Influenza Strategy 2019–2030 and aligns with WHO’s preferred product characteristics for next-generation influenza vaccines. These priorities reflect advances in scientific understanding and lessons learned during the COVID-19 pandemic.

In December 2025, WHO issued updated preferred product characteristics to guide the creation of safer and more effective influenza vaccines. The aim is to develop vaccines that provide broader and longer-lasting protection beyond a single flu season, improve defense against severe illness, and are suitable for use in low- and middle-income countries. The guidance also emphasizes the importance of technologies that can be transferred to manufacturers in these countries to enable regional production capacity.

The FVIVA was developed through close collaboration between WHO and international experts specializing in improved, next-generation, and universal influenza vaccines. As of February 2026, 46 next-generation influenza vaccine candidates are in clinical development, utilizing a range of technological platforms, according to the Influenza Vaccines Research and Development Roadmap.

Additional analyses are available in a supplement published in the journal Vaccine.

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