Socio-Economic Value of Adult Immunisation Programmes

Global Demographic Transitions and Health Challenges

The world is currently undergoing significant demographic shifts, with ageing populations as the dominant trend. For infectious diseases, such as shingles and pneumococcal disease, the incidence and severity of symptoms can increase with age and are associated with a substantial hospitalisation burden amongst this population. Healthcare resource use associated with noncommunicable diseases also increases with population ageing. This necessitates readiness of health and social care systems to meet these challenges. Concurrently, the “tripledemic” of COVID-19, influenza, and RSV, along with rising rates of chronic diseases among lower age groups, places immense pressure on healthcare systems already grappling with treatment backlogs and the growing challenges of antimicrobial resistance and other pandemic threats.

Shifting Focus to Prevention – Vaccination as a Tool

Addressing these challenges requires a paradigm shift from primarily treatment-focused healthcare interventions to preventive interventions, leveraging novel technology and innovations and including vaccination as a powerful tool. A prevention mindset is often adopted in other sectors beyond healthcare (e.g. road safety and workforce health and safety) to prevent harmful health outcomes and productivity losses and promote societal well-being. Similarly, preventive public health interventions are recognised as essential in supporting healthcare systems, promoting healthier lives, and fostering productivity and societal well-being within societies. Vaccination stands as a fundamental preventive measure, integral to achieving global health goals like the UN Sustainable Development Goals (SDGs).

Adult Immunisation Gaps and WHO’s Strategic Priority
While substantial progress has been made in childhood immunisation globally, the value of adult immunisation programmes often remains overlooked. Access to adult vaccinations is inconsistent across countries, with limited inclusion in routine immunisation schedules. The WHO’s IA2030 aims to promote recommended immunisations throughout the life-course, emphasising the need to raise awareness of the benefits of adult immunisation and national strategies for life-course immunisation.

Overview of our report and methods

This report demonstrates the health and socioeconomic value of adult immunisation programmes against seasonal influenza (influenza), pneumococcal disease (PD), herpes zoster (HZ), and respiratory syncytial virus (RSV) in ten countries (Australia, Brazil, France, Germany, Italy, Japan, Poland, South Africa, Thailand, and the United States of America).

Results are based on:

1. A targeted literature review of the published evidence on the burden of these vaccine-preventable diseases in adults and the health, healthcare system, and societal benefits of immunisation.
2.  Health economic modelling to estimate the benefit-cost ratios and net monetary benefits associated with adult immunisation programmes in a sample of up to 10 countries.

The findings support the critical role of robust adult immunisation programmes in addressing major health and societal challenges while aligning with and advancing critical global agendas such as the UN SDGs, the UN Decade of Healthy Ageing (2021–2030), and the WHO Immunisation Agenda 2030 (IA2030).

The Broader Value of Adult Immunisation
Our review found significant evidence for the value of adult immunisation, which included examples from across the three overarching domains of vaccine value: value for population health, value for healthcare systems, and value for society.

The Value of Adult Immunisation for Population Health

Vaccine-preventable diseases continue to impose a substantial burden on adult populations, causing mortality and severe health consequences. Evidence shows that adult immunisation is highly effective in preventing diseases, their sequelae, and mortality, particularly in older adults and those with chronic health conditions.
The Value of Adult Immunisation for Healthcare Systems

Infections caused by influenza virus, streptococcus pneumoniae, RSV, and reactivated VZV significantly contribute to healthcare resource utilisation and associated costs. Adult immunisation programmes are highly cost-effective and can result in net cost savings for healthcare systems. Recent studies have highlighted that these programmes not only offer health benefits but also yield financial gains by averting hospital inpatient and emergency care.

The Value of Adult Immunisation for Society

Vaccine-preventable diseases impact productivity and result in a significant socioeconomic burden. Expanding adult immunisation programmes and coverage can lead to substantial productivity gains by individuals and their caregivers and economic benefits for society. Additionally, adult immunisation programmes can contribute to health and economic equity within countries, particularly benefiting vulnerable populations and underserved communities.
The research also shows that many broader elements, for example societal-economic elements such as productivity value, are currently underrepresented in the academic literature. Without such evidence, the full value of immunisation programmes is likely underestimated by policy- and decision-makers, risking suboptimal investment decisions.

The Benefit-Cost Profile and Socioeconomic Impact of Adult Immunisation

Across the ten countries, our analysis of the four immunisation programmes demonstrates that adult immunisation programmes produce benefits likely large enough to offset their costs and generally outweigh them many times over. Across all countries and disease programs, these programmes return up to 19 times their initial investment when monetising the full spectrum of benefits using the most common valuation approach as applicable to each programme. This is the equivalent of billions of dollars in net monetary benefits to society and corresponds to about $4637 for one individual’s full vaccination course.

These results, based on mostly conservative estimation methods and inputs, are proportionate with returns observed in childhood immunisation programmes – widely recognised as some of the most cost-effective interventions available to healthcare systems.

Discussion and Recommendations

The burden of vaccine-preventable diseases is projected to rise, underscoring the importance of robust adult immunisation programmes. Adult immunisation programmes produce value for society by averting death, serious disease, and productivity losses. They also support equity and the fight against antimicrobial resistance. Expanding access to a broader adult population can enhance overall cost-effectiveness and net cost savings for healthcare systems, as well as support healthcare system capacity and resilience.

However, there are significant gaps in evidence regarding the broader elements of the value of immunisation programmes, indicating a critical need for further research to prioritise and enhance adult immunisation programmes for the benefit of society and public health. Closing these knowledge gaps is vital for informed decision-making and targeted policy interventions that aim to optimise the value of adult immunisation programmes.

Key Recommendations

1. Adopt a prevention-first mindset and provide robust funding for adult vaccination programs
   Now, more than ever, healthcare systems must invest in strategies to cope with unprecedented and growing demand. Prevention must be at the heart of such strategies, and robust adult immunisation programmes are a fundamental component of effective prevention.
2. Implement and optimise adult immunisation programmes as part of a life course immunisation approach
   The burden of vaccine-preventable diseases is projected to rise, underscoring the importance of robust adult immunisation programmes. Expanding access to a broader adult population can generate more value and higher net cost savings for healthcare systems and society. Adult immunisation programmes also present a great opportunity to help our societies age well and sustainably long into the future – and deliver an excellent return on investment in the process.
3. Expand and develop the evidence base for the value of adult immunisation programmes
   There are significant gaps in evidence regarding the broader elements of the value of immunisation programmes. Further research is needed to close these knowledge gaps, which is vital for informed decision-making and targeted policy interventions that aim to optimise the value of adult immunisation programmes. More robust data collection systems, widely accepted methods, and transparent/open data access would allow more accurate quantification of these values. It is especially important to close these information gaps in middle and lower income countries.