Let’s be clear. Vaccines are one of the most cost-effective and successful technologies to save lives ever developed. They save between 2 to 3 million lives every year, constitute a sound and broad-ranging investment in a country’s future workforce and productivity and, when vaccination rates are high enough, protect the non-vaccinated in a population through the effects of herd immunity.

Universal childhood immunisation programmes around the world are also drivers for addressing inequality by focusing on the benefits of health equity; reducing the negative effects of childhood illness through immunisation has been shown to positively affect a child’s ability to attend school and attain higher education levels, which can give them the opportunity to lead more productive lives. Investing in the health of children and youth leads to greater future investment in human capital as investors are more likely to focus on environments that do not carry a heavy disease burden.

So, given the benefits and the scientific consensus on the efficacy and safety of vaccines, why is the anti-vaxxer movement growing so fast?

Well, the truth – as in so many cases – is a bit more nuanced. First, just how big is the impact of the anti-vaxxer voice? In developed nations, there is a definite mis-match between the perceived size of the anti-vaxxer movement and the actual number of vaccine exemptions being granted, which remains very low – highlighting something of an attitude-behaviour gap. This is reflected in studies by the Vaccine Confidence Project, which show rather high levels of vaccine scepticism in European countries – notably France and Poland – that nevertheless have an overall high uptake of vaccines. Looking worldwide, vaccine hesitancy is only one of a number of factors that can have adverse effects on uptake – and other familiar factors such as costs, budgets, delivery and education all remain far more significant issues affecting vaccination numbers. For instance, in January 2019 the All-Party Parliamentary Group on Vaccines for All released their 10-year forecast report on the state of global vaccines and health, drawing attention to the fact that a growing percentage of under-immunised children now live in middle-income countries and in failed states – two categories of developing countries whose immunisation programmes are not comprehensively supported by the current ODA architecture.

And yet, in their list of ten global issues threatening the world in 2019, the WHO ranks vaccine hesitancy alongside other well-established threats such as Ebola, HIV and Climate Change. Why has this issue been raised to such importance, when, as mentioned previously, vaccine price, quality and supply coverage remain massive constraints on achieving immunisation coverage? I think, here, there is a certain level of incredulity amongst the scientific community and most world leaders that the anti-vaxxer movement should even be a thing. But in a political debate landscape that is being co-opted and exploited on so many levels by populist rhetoric, it is a thing, and it is growing – even if the absolute numbers are still relatively small. Italy has had one of Europe’s strongest anti-vaxxer movements, indulged by a round of U-turns on vaccination policy by their populist coalition government. In France, the birthplace of none other than Louis Pasteur, a pioneer of vaccination, Marine Le Pen was strongly opposed to plans to make 11 vaccines mandatory for all young children. In the US, although overall vaccination rates are high, there are significant and growing clusters of non-medical exemptions (NMEs) being granted. Hot spots of refusal are also a contagion in themselves; and the use of NMEs spreads outward from locus areas of high use. There have been very well-publicised outbreaks of measles in both Italy and the US in recent years, and whether these can be directly attributed to this anti-vaxxer movement is a moot point but the symmetry is worrying. And the issue does not just affect the US and Europe. In Japan, young females are turning away from HPV vaccination following negative press coverage in popular media. In Pakistan and Nigeria, Polio is stubbornly resistant to eradication due in part to system-wide socio-cultural opposition to vaccination programmes there.

Another reason why this needs to be seen as a truly global problem is that for some time now, vaccine refusers and questioners have been able to connect via social media networks and drive public anxieties through a negative mix of misinformation, distrust in experts and officials and strong beliefs in alternative medicines. This has become so extreme that even Facebook (a platform normally not known to make a move on such matters) has announced that it will no longer carry anti-vaccination adverts and will address some of the algorithms that inflate and group misleading information. But this problem cannot be addressed by just a series of technical fixes. New champions are needed to communicate the benefits and importance of vaccination on a more profoundly human and emotional level, that is accessible to all members of the global community. We probably need to frame it as a greater collaborative effort. As Italian virologist Roberto Burioni puts it: “being vaccinated isn’t an act of self-protection, but an expression of one’s responsibility to society”.

Above all, we need to listen to people’s concerns and frame our arguments in favour of vaccination in a way that connects with people. Here, I am reminded of the moving letter written by the children’s author, Roald Dahl, about the death of his daughter Olivia from measles in 1964. I still remember being read this letter when I was myself a child, during a school assembly. It was written before the MMR jab was introduced in the UK in 1988, and was intended to communicate in a frank and direct way with a population that was uneasy about the introduction of this new medical programme. Thirty years later, despite the successes of such programmes, coverage levels are dipping again. Dahl was world-famous for his vivid, colourful and, at times, scary use of language. If he was here now, I wonder what he would say.