While some are doubling down on their rejection of vaccines, the scale of the Covid-19 crisis is eroding resistance in others

The coronavirus pandemic may be prompting some anti-vaxxers to question their views, experts say, but others are doubling down – and vaccine hesitancy, amplified by some celebrities, could seriously undermine a future inoculation programme.

According to the World Health Organization (WHO), 70 candidate coronavirus vaccines are being developed, with three already in clinical evaluation. The world’s small but vocal anti-vaccination community seems divided on how to respond.

“The extremists, the belief-driven groups who reject vaccination on principle, whose aim is to disrupt and polarise, they’re not changing, in fact they’re capitalising,” said Heidi Larson, director of the London-based Vaccine Confidence Project (VCP).

Some high-profile personalities with big social media followings have also expressed scepticism. Novak Djokovic, the world No 1 tennis player, suggested on Facebook that his opposition to vaccines might prevent his return to the sport, saying he “wouldn’t want to be forced by someone to take a vaccine” to travel.

The outspoken British rapper M.I.A. also drew widespread criticism for tweeting: “If I have to choose the vaccine or chip I’m gonna choose death”, while the Australian actor Isabel Lucas was dropped as ambassador for a girls’ charity after saying she did not “trust the path of vaccination”.

M.I.A (@MIAuniverse) If I have to choose the vaccine or chip I'm gonna choose death - YALA

However, Larson said there was also evidence that people who were “less sure for some reason, who maybe have issues with just one particular vaccine – the MMR jab for their children, for example – may behave differently in the context of this pandemic”.

The VCP has launched an 18-month study with local partners around the globe, conducting national polls and examining online conversations about the coronavirus to try to measure attitudes towards a future vaccine.

Larson said that after analysing more than 3m social media posts a day between January and March, she was confident the vast majority of people were “eager for a coronavirus vaccine, and as soon as possible”.

Facebook Twitter Pinterest World no 1 Novak Djokovic said his opposition to vaccinations could prevent him from returning to tennis. Photograph: Simon M Bruty/Getty Images

There will, however, be resistance. The anti-vaccination movement has been growing globally in recent years, fuelled partly by a long-discredited paper by the disgraced British doctor Andrew Wakefield, who fraudulently claimed a link between the measles, mumps and rubella (MMR) vaccine and autism in children.

According to the WHO, which identified “vaccine hesitancy” as one of the top 10 health threats to the world last year, depending on the disease between 75% and 95% of the population must be vaccinated to ensure herd immunity.

A 2018 Wellcome Trust survey of attitudes to vaccines globally found eight in 10 people (79%) somewhat or strongly agree vaccines are safe, while 7% somewhat or strongly disagree. Numbers vary around the world, with 72% in North America and 73% in northern Europe agreeing vaccines are safe, but only 59% in western Europe and 40% in eastern Europe.

The scale and gravity of the global coronavirus crisis may, however, be eroding vaccine resistance. A recent VCP survey in the world’s most immunisation-averse country, France, where 33% do not view vaccines as safe, found only 18% of respondents would refuse a coronavirus vaccine.

A poll in the UK in mid-March found about 7% of people would reject a coronavirus vaccine, while a second survey in early April – by which time the Covid-19 death toll was beginning to rise fast – showed the percentage had dropped to 5%.

In Russia – where according to the Wellcome Trust only 62% of people agree vaccines are effective – there are signs that concerns over the coronavirus crisis have caused conflict among anti-vaxxers and medical sceptics.

The administrator of The Truth about Vaccines, one of the largest social media groups dedicated to the issue, expressed frustration about the lack of discipline among its 100,000 members.

“You know what surprises me?” the anonymous administrator posted. I’m surprised by the reaction of vaccine opponents in this group. Many … believe there’s a coronavirus epidemic in Russia. That people are sick and dying from coronavirus.”

In Italy, Claudio Simion of the leading anti-vaxxer group Comilva said a vaccine was not the only solution and “may be a way to calm people”, but added: “We are not hostile towards vaccines out of principle”.

Elsewhere, however, the pandemic appears to have hardened anti-vaxxer attitudes. In the US, prominent figures in the movement have seized on Covid-19 to reinforce their arguments and push conspiracy theories.

Del Bigtree, the producer of Vaxxed, the 2016 “documentary” written by Wakefield, has put together an hour-long presentation – still available on Facebook and YouTube – that argues that Covid-19 is a set-up by the pharmaceutical industry to enrich itself.

Robert Kennedy Jr, the son of the assassinated Democratic leader, accused Bill Gates and top public health officials on Twitter of plotting to produce a vaccine with “unique and frightening dangers”.

Scott Ratzan, of the City University of New York’s school of public health, said he was alarmed by the results of a poll in New York City showing that only 53% of residents were sure to take a coronavirus vaccine and 29% would refuse.

“What if large numbers of people decide not to vaccinate themselves or their children?” Ratzan said. “Right now, barely half of New Yorkers tell us they’ll do that. If that is the case, we won’t be able to protect our community against a new wave.”

Larson said the timing of the vaccine’s release, forecast for some time in 2021, could be critical, with many likely to be deterred by any suggestion it might have had been rushed and not properly tested.

On balance, Larson said, she was not convinced the coronavirus would have a direct impact on anti-vaccination sentiment. But she did foresee a possible indirect impact, with coronavirus fears leading to the delay of measles vaccinations in 24 countries and their cancellation in 13 others, prompting concern from both the WHO and Unicef.

If vaccine hesitance does decrease after the Covid-19 crisis, Larson said, it would likely be as a result of “outbreaks of other diseases such as measles increasing because parents are afraid to take their infants to health centres during the pandemic”.

Additional reporting by Ed Pilkington, Andrew Roth and Angela Giuffrida