Vaccine Hesitancy

I am an immunologist by training who developed molecular biology and virology expertise as my work evolved. I was one of the authors on the paper that first described the genome sequence of the SARS coronavirus in 2003, and I was the lead immunologist on the first licensed Ebola virus vaccine — work published in Nature Medicine that has since been used to control outbreaks in sub-Sub-Saharan Africa. I am telling you this not to establish authority but because what follows is not opinion dressed as expertise — it is expertise that has watched the same pattern repeat for fifty years.
 Vaccine hesitancy is not a product of the internet. It is not a product of social media. It is much older than both, and understanding that is essential to understanding why it is so difficult to combat. In January 1974 a small case series of 35 children was published in a British medical journal. The authors reported neurological problems in children who had recently received the pertussis — whooping cough — vaccine. The study was deeply flawed. It was a case series, not a controlled trial. It could not establish causation. Twelve of the 35 children had shown signs of neurological vulnerability before vaccination. The authors themselves acknowledged that chance temporal associations between vaccination and illness are inevitable in young children, who are vaccinated repeatedly during exactly the period when neurological conditions first become apparent. None of that nuance made it into public discourse. Vaccination rates in the UK fell from 78% to around 30% by 1978. In some areas coverage dropped as low as 9%. Three whooping cough epidemics followed. Children died. All of this happened before the internet existed. Twenty-three years later, Andrew Wakefield published a paper in The Lancet claiming a link between the MMR vaccine and autism. The paper involved twelve children. It was later found to be not merely flawed but deliberately fraudulent — Wakefield had undisclosed financial incentives and had manipulated both the data and the ethics of the study. Every co-author retracted. The Lancet retracted. Wakefield lost his medical licence. He has never retracted. The damage — a collapse in MMR vaccination rates internationally and measles outbreaks in populations that had previously eliminated the disease — persists to this day. This also happened before social media was a significant force. Both episodes exploited the same mechanism: the rational fear of a parent confronted with the possibility that something they choose to do to a healthy child might harm that child. The logic is emotionally compelling even when it is statistically illiterate. The probability that the vaccine causes harm is low. The probability that the disease causes harm is higher. But the disease is invisible until it strikes, and the vaccine is a visible act the parent takes. We are not wired to weigh invisible risks well. Then came COVID. I worked on pandemic preparedness before COVID-19 existed. What I watched happen was not a failure of science — it was a failure of the information environment in which science had to operate. Public health guidance changed repeatedly in the early months. It was supposed to. That is what evidence-based guidance does when evidence accumulates. To a scientifically literate audience, updated guidance signals a system working correctly. To a public with limited scientific literacy, it signalled chaos and incompetence. Pre-print servers — repositories of unreviewed research — allowed genuinely bad science to circulate with the visual authority of academic papers. Under normal conditions this research would never have survived peer review. Under pandemic conditions it spread globally before anyone could assess it. And into this environment came social media health influencers who never express uncertainty, carry no professional accountability, and in many cases have direct financial incentives to sell alternatives to vaccines. Foreign state actors ran coordinated disinformation campaigns targeting mRNA vaccine technology — a genuinely novel platform that was developed rapidly and was therefore genuinely unfamiliar to the public. The unfamiliarity was real. The conclusions drawn from it were not. The mRNA vaccines against COVID-19 are now among the most studied medical interventions in history. The HPV vaccine — another target of the same disinformation ecosystem — is demonstrably eliminating cervical cancer in the first cohorts of young women who received it as adolescents. The fear that drives vaccine hesitancy is not irrational. The parental instinct to protect a child is one of the most powerful forces in human psychology. What is irrational is a media and information environment that systematically amplifies that fear, provides it with false scientific credibility, and faces no accountability for the consequences. Fifty children died in the whooping cough epidemics that followed the 1974 scare. That happened without social media, without the internet, with a single flawed study and a credulous press. We now have thousands of people with financial incentives to spread health misinformation, platforms that face no liability for hosting it, and foreign governments with geopolitical reasons to undermine public health in their rivals' countries. The question is not whether this will cause harm. It already has and continues to. The question is what regulatory and structural changes would be required to make the people and platforms responsible for spreading demonstrably false health information accountable for its consequences. The views expressed here are my own and do not reflect the positions of the institutes where I have worked