In our previous columns, we highlighted life-course immunization as a cost-effective way to improve health, support health system sustainability, and promote economic prosperity. At a global level, effective vaccination may help mitigate health risks such as infectious diseases and antimicrobial resistance (AMR), that both have significant impact on health and wellbeing as well as on the global economy.
As the global population continues to age, prevention of disease becomes more important for easing pressure on health systems and ensuring their sustainability. Similarly, as retirement age increases and people work to older age, immunization across the life course is becoming more relevant to workforce productivity.
Unfortunately, a new study by the UK-based Office of Health Economics (OHE) shows that while substantial progress has been made in childhood immunization globally, the value of adult immunization programs often remains overlooked. It also found that access to adult vaccinations is inconsistent across countries, with limited inclusion in routine immunization schedules. The OHE is the world’s oldest independent health economics research organization that works in partnership with universities, government, health systems, and the pharmaceutical industry to research and respond to global health challenges.
Commissioned by the International Federation of Pharmaceutical Manufacturers & Associations (IFPMA), the study assessed and synthesized the evidence for the broad, socioeconomic value of adult immunization programs, focusing on influenza, pneumococcal disease, herpes zoster, and respiratory syncytial virus (RSV) programs in 10 countries.
The OHE researchers conducted a literature review of evidence published in the PubMed database from 2017 to 2023 and supplemented search results using a snowballing approach. They then used a published Value of Vaccines framework to structure their assessment.
The study found that adult immunization is highly effective in preventing diseases, their complications, and associated deaths, particularly in older adults and those with chronic health conditions. Moreover, adult immunization programs potentially produce additional health benefits by protecting unvaccinated individuals.
The study revealed an extensive evidence base showing that adult immunization programs are highly cost-effective and can result in net cost savings to healthcare systems. For example, recent studies in Australia and Germany have highlighted that vaccine programs for influenza and pneumococcal disease not only produce health benefits but also yield financial gains by averting hospital inpatient and emergency care.
Programs to expand uptake can also be very cost-effective, perhaps as result of economies of scale, given the low variable costs compared to fixed costs associated with delivering immunization programs. Evidence from Germany and France, for example, indicates that expanding adult immunization programs for herpes zoster and influenza, respectively, may increase their overall cost-effectiveness.
The study found that adult immunization programs can potentially provide a positive return on investment in the form of both increased tax revenues and productivity, outweighing the costs of the programs to governments many times over.
The burden of vaccine-preventable diseases, and the benefits of adult immunization programs, are particularly concentrated in more socioeconomically disadvantaged sub-populations. The study noted that expanding adult immunization schedules to include younger adults can reduce inequity in the distribution of vaccine-preventable diseases. It also found that adult immunization programs can reduce the likelihood of unnecessary prescribing of antibiotics for respiratory illness, and novel antimicrobial vaccines can help to protect against the progression of AMR.
While there is growing evidence of the broad societal value of vaccination, the study found many gaps in the recognition of the value of adult immunization. No evidence was identified relating to macroeconomic effects, the enablement value to other interventions, or effects on the quality of life of caregivers.
According to the study, these gaps can be explained by the methodological challenges involved in collecting and analyzing evidence of broader value, and in part by the “narrow” decision-making frameworks which are typically used to evaluate immunization programs. Given a lack of transparency and lack of standardized evidence appraisal methods, the evidence which does exist is not consistently or comprehensively recognized in decision-making about adult immunization policy.
The evidence uncovered by the study supports the critical role of optimizing adult immunization programs in addressing major health and societal challenges while aligning with critical global agendas such as the UN Sustainable Development Goals (SDGs), the WHO Immunization Agenda 2030 (IA2030), and the UN Decade of Healthy Ageing.
However, the research also clearly shows that many dimensions of the value of adult immunization programs are currently underrepresented in academic literature. Without such evidence, the full value of vaccination programs is likely underestimated by policy- and decision-makers, risking suboptimal investment decisions, the study concluded.
Teodoro B. Padilla is the executive director of Pharmaceutical and Healthcare Association of the Philippines (PHAP). PHAP represents the biopharmaceutical medicines and vaccines industry in the country. Its members are in the forefront of research and development efforts for COVID-19 and other diseases that affect Filipinos.
