The true impact of vaccines may be significantly under-rated as researchers have tended to look only at the direct benefits of immunisation programmes. Professor David Bloom of the Harvard T.H. Chan School of Public Health says this approach is too narrow.
Bloom, an expert in economics and demography, told a Pfizer-sponsored symposium at the European Public Health Conference in Vienna that population ageing means the broad positive effects of immunisation are set to become even more important.
“The value of vaccines goes well beyond their utilitarian health benefits,” he said. “The full social and economic benefits are estimated to yield a return of between 12% and 18% – a great return by any standard.”
Even those striking figures may understate the total impact. Ensuring that children make it to adulthood unlocks a lifetime of productivity while maintaining good health later in life translates into gains: not only can healthy older adults work longer, they make valuable social contributions by volunteering, and by taking care of grandchildren and one another.
Bloom also pointed to other positive aspects of adult vaccination such as ‘herd effects’ that reduce the presence of disease in communities. Vaccines also curb the risk of other illnesses that can follow infection with flu and pneumococcal disease. For example, the risk of developing pneumonia is greater after infection with flu which means flu vaccines can indirectly reduce the risk of pneumonia.
Is demography destiny?
One of the reasons vaccines have been receiving too little attention from economists is that the case for universal childhood immunisation was already a no-brainer. The health gains alone are so compelling – and the vaccines so safe, effective and affordable – that there was little for academics to argue over.
Now, with more sophisticated vaccines becoming available and ‘life-course vaccination’ entering the public health lexicon, it is time to build a more robust case for immunisation. The ageing population in particular has pulled elderly immunisation into the spotlight.
Bloom outlined the demographic trends that will shape our future. All European countries will see double-digit growth in the proportion of people aged over 65 in their populations: “By 2045 more than half of Europe’s population will be in countries that are older than Japan is today.”
He said that until two decades ago demographers were primarily anxious about the rapid population growth that was taking place globally. Today, rather than worrying about the absolute number of people on the planet, the focus has shifted to the proportion of older people in society.
However, Bloom said he remained optimistic that the world would adapt to this demographic challenge, just as it did when the global population jumped from three billion to six billion during the 20th century. As long as new technologies and strategies for managing the change are embraced, demographic doomsday forecasts need not materialise.
“There is some alarm about the share of global population that will be aged 65 years and older,” he said. “Elderly vaccination could be part of the solution.”
Lessons from education
It is almost beyond question that investing in early education is good value. In countries, rich and poor, universal education has been the gift that keeps on giving: helping to equip people with the skills they need to improve their lives and be economically productive. It can also be a powerful force for social equality.
However, until the tail end of the 20th century, the case was not so cut and dried. Economists at the World Bank studied the rate of return on schooling by reviewing 150 top quality research studies on the topic. They looked at how beneficiaries of education fared later in life in terms of earnings and other indicators, and concluded that investing in education delivered returns of around 10%-20%.
“From then on, they couldn’t avoid the realisation that more investment was needed in education,” Bloom recalls. “We need to take a page from that playbook; we need to do for vaccines what has been done for education. We will then see vaccines elevated to the level of education as an instrument of progress and human betterment.”
For new vaccines, this could mean adding broad economic indicators to clinical trials which normally focus on vaccine safety and effectiveness. For older vaccines, following up on people who participated in previous studies could unlock a wealth of data by finding how their lives turned out. Clinical trial participants are already randomised so, once the data is collected, it would be relatively straightforward to figure out whether those who were vaccinated were healthier and wealthier than those who were not.
Bloom says this needs to be done country by country and vaccine by vaccine so there is no time to lose. The payback will be a fuller picture of how vaccines influence our lives – which is currently absent. “The inattention to the full economic benefits of vaccines is quite stunning,” he said. “Under-evaluation goes hand-in-hand with under-investment in vaccines and research, implying that society is not allocating resources efficiently.”
Not only is the impact of vaccines under-estimated, the risk of some vaccine-preventable diseases is also severely underrated, according to a European survey. In Europe, there are an estimated three million cases of pneumonia every year, resulting in one million hospitalisations and 120,000 deaths. Yet most Europeans know surprisingly little about the disease.
The PneuVUE study, carried out by Ipsos MORI, surveyed over 9,000 people aged over 50 years in nine countries. It found that 88% of people claimed to know what pneumonia is – but just 44% knew that some forms of pneumonia are contagious and 20% did not identify the disease as being a lung infection.
Dr Jane Barratt, Secretary General of the International Federation on Ageing, described the PneuVUE study as one of the most important she had been involved in, adding that adult vaccination against flu and pneumococcal disease can help older people to retain autonomy.
Barratt, who also leads the World Coalition on Adult Vaccination, said vaccination was an important part of her work advocating for older people, and she called on other organisations to join her in putting it on the health policy agenda. “It’s time that diabetes organisations and those working with people who suffer from lung conditions join the conversation too,” she told Vaccines Today.