One of the many pressing issues facing governments across Europe during the battle against the coronavirus pandemic was how they could convince reluctant adults to get the jab.
A study has looked into what sort of messaging was most effective in convincing these groups, and there was a clear winner in the United Kingdom: the likelihood of being able to travel abroad.
Other countries saw different results, however, with a number of European populations not swayed by the promise of a vaccine passport.
Researchers found that in countries with populations with lower levels of basic knowledge about health and higher prevalence of conspiracy theories, unvaccinated adults were less likely to change their mind regardless of the public messaging.
COVID-19 vaccines have proved a powerful tool in protecting health services by reducing the chances of people becoming seriously ill with coronavirus. But a significant minority of the population in many European countries remain sceptical about getting vaccinated, due to a number of factors.
These include mistrust of authorities, as well as worries about the speed of vaccine development and potential side effects.
Researchers from the London School of Economics, the Technical University of Munich, and the University of Trento studied more than 10,000 unvaccinated adults in the UK, France, Germany, Italy, Poland, Spain, Sweden and Bulgaria.
There was a big variation in vaccine take-up across the eight countries at the time of the study, with hesitancy at around 61 per cent in Bulgaria and as low as 6.4 per cent in Spain.
Three messages, mixed results
During the spring and summer of 2021, the adults in the study were given information about the COVID-19 vaccines available to them, and also shown one of three messages from public health campaigns aimed at increasing vaccination rates.
One emphasised how the vaccines reduce the risk of serious illness or death.
The second showed how a vaccine passport would reopen travel abroad.
The third explained how vaccinated people were free to enjoy restaurants, cinemas, and gyms without restrictions.
All three messages were effective in convincing German adults.
In the UK, the promise of being able to travel abroad brought the number of people willing to be vaccinated up from 22 per cent to 28 per cent.
However, in all the other countries, none of the messages were effective, with unvaccinated adults in Spain and Italy becoming even less likely to get vaccinated after reading the messages.
So why did something that worked in Germany backfire in Italy and Spain?
“One plausible explanation is the difference in health literacy levels in Germany compared to Italy and Spain,” Matteo Galizzi, associate professor of behavioural science at LSE and one of the authors of the study, told Euronews Next.
People don’t all have the same ability to understand the basics of risk and risk reduction, and have different views on the benefit-risk balance of getting vaccinated depending on their own age and health, he said.
Vaccine hesitancy gender gap
One notable pattern the study picked up was the gender gap in vaccine hesitancy rates, with women more hesitant in five of the eight countries surveyed.
“In most of the countries we find a statistically significant and relevant difference between men and women in vaccine hesitancy, Galizzi said, adding that “it is one of the first times it is documented so clearly”.
He said this could potentially be attributed to two things. Firstly, the fear about side effects from vaccines, and specifically worries about effects on fertility.
Secondly, the fact that COVID-19 illness seems to affect women less seriously than men, which “could potentially be an almost rational reaction to explaining more resistance to vaccination”.
Lessons for policymakers
The researchers say the study, published in the peer-reviewed journal Science Advances, provides significant lessons for current and future vaccination campaigns.
While the European Commission has called for a coordinated vaccination strategy across the EU, the researchers cautioned against a “one-size-fits-all” approach.
Galizzi argued that while coordinated vaccination campaigns can be beneficial regarding provision of vaccines or prioritisation of certain users, “vaccination campaigns must be tailored at the level of individual countries”.
“There is no single vaccination campaign, or public health message that we have tested, that is working across all the countries,” he said.
One of the study’s key takeaways stems from the fact the acceptance of either the mRNA vaccines made by Pfizer-BioNTech and Moderna on the one hand, or AstraZeneca’s jab on the other, varied significantly from one country to the next.
It showed a third of British participants reported high levels of trust in the UK-made vaccine, compared to less than 5 per cent of German and Italian participants.
“These insights motivate an important policy lesson: COVID-19 vaccination and booster campaigns will likely be more effective if citizens can actively decide which kind of vaccine they will receive,” the study’s authors wrote.
The researchers argue public health messages focusing on the rigorous and extensive testing of vaccines, as well as transparent communication about prevalence, prevention, and treatment of possible side effects, could prove most effective in addressing the concerns of vaccine-hesitant adults.
“This study shows that public health messaging - and subtle information nudges - can shape our decisions. We now know the major reasons why some adults are hesitant to get the vaccine,” said Galizzi.
“Public health messages need to respond to these concerns, and to focus on communicating the rigorous and extensive testing of vaccines, and the extent to which risks of side effects from jabs compare to risks from COVID and long COVID," he added.