Fewer people in the UK and US would definitely take a coronavirus vaccine than is required for herd immunity, and misinformation could push these levels further away from that goal, a new study has suggested.
Researchers found that before being exposed with misinformation, 54% of those surveyed in the UK said they would definitely accept a vaccine, with 41.2% in the US agreeing.
After being shown online misinformation, that number dropped by 6.4 percentage points in the UK and by 2.4 percentage points in the US.
Some experts estimate a Covid-19 vaccine will need to be accepted by at least 55% of the population to provide herd immunity while others suggest even higher numbers will be needed.
Researchers from the London School of Hygiene and Tropical Medicine, who conducted the study, say the findings can help inform Covid-19 vaccination messaging and engagement strategies to mitigate the negative impacts of misinformation.
According to the study, which is under peer-review, there have been widely circulating false stories about the virus as well as potential vaccines and treatments.
The rumours include claims that 5G mobile networks are causing the virus, that the pandemic is a conspiracy or a bioweapon and that vaccine participants have died after taking a candidate – none of which are true.
Study lead Professor Heidi Larson, from the London School of Hygiene and Tropical Medicine, said: “Covid-19 vaccines will be crucial to helping to end this pandemic and returning our lives to near normal.
“However, vaccines only work if people take them.
“Misinformation plays into existing anxieties and uncertainty around new vaccines, as well as the new platforms that are being used to develop them.
“This threatens to undermine the levels of Covid-19 vaccine acceptance required.
“Although studies have examined the effect of Covid-19 misinformation on public perception, the link between exposure to misinformation and intent to receive a future vaccination is less well known.
“This study plugs that knowledge gap.”
In the study, 3,000 respondents in each country were shown widely circulating misinformation on social media surrounding a coronavirus vaccine between June and August 2020.
The remaining 1,000 were shown information about a Covid-19 vaccine that was factual to serve as a randomised control.
Those with the highest educational attainment below postgraduate degrees, low income groups, and non-whites are more likely to reject a coronavirus vaccine, according to the study
Women were also more likely to refuse a vaccine than men, the researchers found.
However, the findings indicate more respondents in both countries would accept a vaccine if it meant protecting family, friends, or at-risk groups.
The main barriers to positive intent to vaccinate were concerns over safety and a belief that they would not be at risk of contracting Covid-19 or would not become ill if they did, the study indicated.
People who wanted to wait until others had been vaccinated were less likely to outright reject a vaccine, researchers found.
Prof Larson said: “Vaccine confidence has a significant impact on global health. Positive confidence means higher acceptance of crucial health interventions while low confidence means heightened risk perception and vulnerability to misinformation.
“Our work has shown that misinformation can change people’s minds and willingness to accept a potential Covid-19 vaccine, a decision which could threaten lives around the world.
“Reported willingness to accept a Covid-19 vaccine is already below the needed herd immunity threshold.
“Exposure to misinformation could push us even further away from that goal.”