Adult immunisation is cost-effective and an excellent return on investment – for every $1 spent we see up to $19 in wider societal benefits. In this article, ILC’s Senior Health Policy Lead, Esther McNamara, sets out the evidence for investing in adult immunisation in the context of demographic change.

We all know prevention is better than cure. If you could press a button that ensured you would never contract a life-changing illness, most of us would press that button, and press it on behalf of our loved ones too. However, despite the vast benefits of immunisation we have collectively experienced in recent years, vaccines don’t always enjoy a great reputation. We can and do prevent dozens of life-changing diseases through immunisation every year, but we are also seeing resurgence of vaccine-preventable diseases that many thought were consigned to the past, including measles and whooping cough. Vaccines are too often met with scepticism when we should be celebrating what we have collectively achieved, both in delivering vaccines and enjoying healthier lives as a result of vaccines.

World Immunisation Week took place back in April 2024 to celebrate the millions of lives saved and years lived in good health thanks to vaccination programmes. The World Health Organisation celebrated 50 years of the Expanded Programme on Immunisation (EPI) which has saved over 154 million lives in that time; this is 6 lives every minute, every year, for 50 years. The Lancet has found that “for every death averted, 66 years of full health were gained on average, translating to 10·2 billion years of full health gained.” Over 10 billion years of life were lived in good health over the last 50 years, thanks to vaccinations; this is a staggering number that has been significantly under-appreciated. We have made immense progress in recent years, but it is clear that we are not cognisant of the enormous benefits we collectively enjoy from vaccination.

If we were all cognisant of the wealth of benefits that immunisation offers, we would prioritise it and expand programmes to as many people as possible across our lives. Adult immunisation has received comparatively little attention and investment when we compare it to childhood immunisation; so says the Office of Health Economics (OHE) who recently published a report setting out the socio-economic value of adult immunisation programmes. They found that each $1 invested in adult immunisation can generate a return of up to $19 for society at large. This return on investment goes beyond many other public health interventions and is equivalent to $4637 for each individual’s course of full vaccinations. An extra $4637 per adult would represent significant economic gains at the national level. In the UK, we have calculated this would mean a potential addition of up to £247 billion to the UK economy. For individuals, this would also generate benefits that we cannot measure: more time spent in good health and able to do the things we choose; spending more time with family and friends, caring, work and volunteering, hobbies, travel, and health-promoting activities.

The OHE report noted that the evidence base for investment in adult vaccines is not as comprehensive, and many health systems do not prioritise adult immunisation because the benefits are not sufficiently understood. ILC’s recent programme of work on life course immunisation cost-effectiveness also built consensus on the need for more evidence in this area, but where the evidence does exist, it points to significant cost-effectiveness at the societal level.

Through events in Japan, India, Switzerland, and the USA, ILC have convened a range of experts in health and finance to understand what needs to change to support expansion of immunisation across the life course. Both ILC and the Office of Health Economics have sought to give health and finance ministers the tools and rationale to begin and expand their investments in adult immunisation programmes: each organisation has respectively published papers setting out, in clear and accessible ways, why adult immunisation is a crucial and worthy investment. It is up to governments and international bodies to keep the momentum on immunisation, and for each of us to take up our recommended vaccines where we can; and most importantly, each of us can be advocates for immunisation within our own spheres of influence.

ILC are clear and committed advocates for immunisation, and our body of work on the subject is available on our Adult Immunisation website. We will continue to make the case for immunisation, and for prevention more broadly, through our work on immunisation and our Healthy Ageing and Prevention Index.