What promotion of vaccine demand for seasonal influenza needs to look like going forward

Here's a brief I wrote a while back about how the confidence in seasonal influenza vaccine is challenged seasonally, and what an effective vaccine demand promotion approach would need look like.

Those who work in promoting demand for vaccines, health services and health technologies know how important it is to address access, health service and health behavioral factors at the same time to promote vaccine demand.

It requires having to concurrently build confidence in the health system, the health worker and the vaccine, through consistent actions of the health system in words, actions, and interventions.

Seasonal influenza is a different epidemiological and demand challenge from routine childhood vaccine-preventable diseases, so vaccine demand promotion strategies need adapting.

COVID-19 pandemic has changed how we experience a seasonal disease like influenza

The experience of the COVID-19 pandemic has had multiple impacts on populations and health systems. Challenges have included erosion of trust in science, vaccines, and health service delivery in communities. Overworked and burned out health workforces have had to contend with supply chain issues, staffing shortages, rapidly changing policies, vaccine hesitancy in their own ranks, and breakdown of the primary heath care delivery, as health systems struggled to support COVID-19 mitigation and vaccination efforts.

As the COVID-19 pandemic drew on, new unanticipated challenges emerged, including pandemic fatigue, major impacts on economic, social and educational outcomes, further polarization of societies, rapid dissemination and amplification of health mis- and disinformation. This has permanently changed how populations will perceive and interact with the health system and emergency response in future emergencies and pandemics.

These above are the lessons learned that should be incorporated in any vaccine demand planning focused on seasonal influenza (see also my recent talk on learnings from COVID-19 on vaccine demand promotion).

The changing epidemiological, vaccine, and information environment factors in seasonal influenza

Seasonal influenza has unique attributes that makes it difficult to ensure high adherence to guidance including robust vaccine uptake. These include factors such as:

• Historic flu vaccine coverage in countries with robust adult flu immunization programmes is quite low compared to childhood routine vaccinations
• Low prioritization in LMIC immunization programmes which have historically focused on children’s vaccines
• Different countries prioritize different population groups for seasonal influenza vaccine, eg pregnant women, older people, health workers, etc.
• In many countries with long-standing immunization programmes for flu, collaborating with the world of work and community-based organizations has helped bring flu shots to people’s workplaces and doorsteps, long before COVID-19 experience.
• Low risk perception contributes to low flu vaccine uptake among general populations and health workers
• Policies encouraging flu vaccination usually are not as far-reaching as those during the COVID-19 pandemic, eg vaccine mandates, making it harder to achieve high vaccine uptake or achieve herd immunity
• Changing seasonal formulation of the flu vaccine can result in varying levels of effectiveness against dominant flu strains, and therefore affecting risk perception and perception of the benefits of the flu vaccination
• Year to year, the dominant flu strain may have different levels of severity or present different symptoms in different populations, which can result in having to provide updated guidance, eg severe outcomes observed in healthy young adults this year compared to last year, which affected children and the elderly
• Respiratory pathogens and flu can cross the human-animal interface, requiring coordination with one health programmes
• Persistent mis- and disinformation about flu vaccine affects vaccine confidence, especially among vulnerable populations, eg pregnant women, minority communities, etc
• Risk comparisons and messaging around COVID-19 vaccine has collided with flu season and flu vaccine campaigns, which have complicated public health responses to twindemics

All of these challenges need active management during and off influenza season, because no matter what time of year it is, the flu season is occurring somewhere in the world, affecting community conversations and health programme responses globally.

We need a comprehensive approach to seasonal influenza vaccine demand promotion

Vaccine demand must be promoted at community level, within health systems, and at a policy level, so that people have confidence and trust in vaccines that vaccines work, are safe and are part of a trustworthy medical system. Many of the factors listed above can impact vaccine confidence and uptake and must be considered when developing effective confidence and demand strategies. High quality health service delivery, supported by adequate supply, and appropriate policies, must meet high community demand for a flu vaccine to reach high vaccine coverage and promote herd immunity and thereby reducing morbidity and mortality.

The speed and effectiveness of emergency response to an unknown respiratory pathogen or a novel influenza outbreak will be determined by a health program’s familiarity with best practices and tools for promoting vaccine demand for seasonal flu. Recent pandemics have taught us that the beginning stages of an emergency are not the time to build from scratch entirely new ways of promoting adherence to public health guidance and promoting vaccine demand.

A strong seasonal influenza programme that uses tools and strategies to address the above challenges effectively will be much better prepared to quickly adapt them to future pandemics and epidemics. An immunization progamme can use a comprehensive understanding to address these challenges to prepare for the next major seasonal flu outbreak and train up capacity for future outbreaks of other respiratory pathogens.

This is actually one of the reasons that we had developed a seasonal influenza module for the WHO/UNICEF manual on how to generate infodemic insights and recommendations. Only an adaptive delivery of services vaccines and information will support high influenza vaccine coverage, season after season. Social listening and integrated analysis for infodemic insights can help generate evidence to implement effective strategies for demand promotion.

A seasonal influenza programme needs to develop these building blocks to apply them in its work

• Learning from the past: what previous flu outbreaks and pandemics have taught us
• State of the global seasonal flu picture
• Essentials of a flu vaccination programme (includes seasonal flu surveillance, vaccine supply, vaccine development, outbreak response, policies, health worker training, microplanning)
• Health equity, vulnerable populations and seasonal flu recommendations
• Introduction of public health and social measures to seasonal flu response
• Building vaccine confidence in health workers
• Supporting health workers to effectively address flu outbreaks
• Building demand for seasonal flu vaccine
• Infodemic management for seasonal flu
• Science communication for seasonal flu
• Building partnerships with the world of work
• Cocreation of guidance and tools with vulnerable populations

Some tools in this are available from the 2021 GAVI/WHO/UNICEF/US CDC comprehensive training to promote vaccine demand and restore routine immunization (materials, videos). We're presenting the curriculum and its evaluation at the American Public Health Conference in a few weeks.

But most importantly, such tools need to be adapted to the changing nature of the vaccine, information environment and epidemiology of seasonal influenza.