While countries in Western Europe have some of the highest vaccination rates in the world, they are still pushing to convince the final chunk of people holding out.
For some European capitals, it's the carrot of vaccine passes; for others, it's the stick of making jabs mandatory.
Austria, for instance, has mandated vaccination from February 1, regardless of age or professional activity. Greece and Italy have mandated that people over the age of 60 and 50 respectively must be vaccinated or face fines.
German Chancellor Olaf Scholz on Wednesday backed mandatory vaccination in the country, which lawmakers are expected to debate later this month. Currently, the country has put restrictions on the unvaccinated, with proof of vaccination or recovery from COVID required to enter bars, restaurants and most cultural and leisure venues. France, which already has a health pass in force, is expected to change it along the lines of Germany's later this month.
But behavioural scientists are wary of the impact such measures could have.
"I think if you make those regulations too strict, then the real anti-vax people, which is a minority, will become more resistant," Julia van Weert, Professor at the University of Amsterdam's Faculty of Social and Behavioural Sciences, told Euronews.
"And I think this is the danger in the long term," she added. "It's going to split society and also in the long term, on other topics, there can be bigger fights and more polarisation."
'Piss off' unvaccinated people
The upcoming change in legislation in France — where about 91% of adults are fully vaccinated, as are 79% of children aged 12 to 17 — has had people descending in the streets.
More than 105,000 people marched across the country on Sunday against the "vaccine pass" — four times more than did on 18 December.
President Emmanuel Macron may have spurred them on. He stated earlier this month "the unvaccinated, I really want to piss them off".
But that kind of language could be counter-productive, say experts.
Professor Martyn Pickersgill, Chair of the Sociology of Science and Medicine at the University of Edinburgh, told Euronews he's "concerned that Macron’s comment risks re-entrenching distrust and disengagement from public health measures, rather than motivating people to engage with vaccination".
However, Macron might claim the French government's strategy has been successful so far. It drove people to get vaccinated by making it mandatory for health care professionals to get the jab and rolled out its COVID health pass, which attests that its holder had either been fully vaccinated, had previously recovered from the disease or recently tested negative. It's a strategy Paris has credited for the health care system's ability to resist an unprecedented surge of infections recently.
In vaccine information we trust?
COVID passes have widely been seen as being successful in getting people to get vaccinated. A study of its impact in Denmark, Israel, Italy, France, Germany, and Switzerland released by The Lancet medical journal in December found that they led to increased vaccinations 20 days before implementation in anticipation, with a lasting effect up to 40 days after.
Yet, despite the restrictions to people's day-to-day lives, some still choose to forgo vaccinations.
According to an EU Barometer released in May 2021, the key reasons for not getting vaccinated against COVID-19 are the belief that the vaccines have not yet been sufficiently tested and worries about the side effects.
The survey, which polled more than 26,000 people over the age of 15 across all 27 of the bloc's member states, also found that the sources EU citizens trust most to give them reliable information on COVID-19 vaccines are health professionals and national health authorities (61% and 44% respectively).
The EU and national governments came a distant third at 20% and 19% respectively, ahead of regional and local authorities and the media (14% and 11%).
"Trust, open communication, and partnerships are essential features of all public health campaigns. Importantly, trust cannot be simply demanded: rather, the trustworthiness of politicians making public health policy needs to be clearly demonstrated," Pickersgill stressed
"The benefits and risks of vaccination must be clearly and openly communicated, otherwise people understandably feel that information is being withheld from them – fuelling distrust," he added.
Not all unvaccinated are anti-vaxxers
Van Weert, meanwhile, warned against generalising the minorities in Western Europe that have not yet got the vaccine as anti-vaxxers and said instead they are "a heterogeneous group of people" comprising communities where misinformation spreads more rapidly. These can be people from lower socio-economic backgrounds, students and migrants but also people who have doubts because of their own medical history and need their concerns addressed specifically.
" I think governments should first do all the efforts that are possible to reach those people before they come with (other) restrictions," she said, calling for more "personalised strategies" involving important stakeholders or key figures in communities.
"It's better if they are reached, for instance, by people that are independent of governments and doctors can play an important role here," she said, as can religious figures including imams and priests.
She flagged for instance the success of a "hesitation hotline" in the Netherlands that unvaccinated people call to discuss their concerns with medical professionals. The service receives an average of 1,000 calls per day.
Will making vaccines mandatory work?
For Van Weert, the impact of making vaccines mandatory in Western Europe is likely to be limited.
"What I know from research is that the added value of making it mandatory is higher when the vaccination rates are lower," she said.
They are also highly unlikely to sway those who are ideologically opposed to the vaccine, she added.
"Anti-vax people, they are so convinced they won't be convinced by anything. I think you better leave those people alone for a while and don't pay all that attention to them all the time. The more they are stigmatised, the less willing they will be to get the vaccination in the end," she concluded.
Pickersgill was also cautious about their impact, telling Euronews that "it’s possible that mandates will ‘work’ exclusively in the sense that they might force some people who were concerned about the effects of vaccines to uptake an offer of vaccination."
"However, this could come at the expense of fuelling public distrust and providing a focal point for resentments that could undermine the wider public health response," he argued.
More than 69% of the EU/EEA population is now fully protected against the risk of severe disease but there are big disparities across the 31 countries of the region.
Denmark and Portugal have fully immunised more than 82% of their population while Austria, Belgium, Finland, France, Ireland, Italy, Germany, the Netherlands, Norway and Spain have rates between 70-78%. Eastern countries, however, have not been quite as successful. Bulgaria has not yet managed to fully vaccinate a third of its population while rates in Romania and Slovakia are below 50%.
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