Respondents who said they get a great deal or fair amount of information on the pandemic from certain online sources, including social media, are more likely to have conspiracy suspicions, the study found.

Meanwhile, those from ethnic minority backgrounds are particularly likely to report believing conspiracy-related statements, according to researchers.

Around 25% of people from an ethnic minority background believed the only reason a coronavirus vaccine is being developed is to make money for pharmaceutical companies, compared with 13% of white people.

People from ethnic minorities were twice as likely (22%) as white people (11%) to report believing that some vaccines cause autism in healthy children.

These concerns are reflected in the finding that people from ethnic minorities (15%) are half as likely as those from white ethnic groups (31%) to say they would like to be vaccinated immediately.

Professor Bobby Duffy, director of the Policy Institute at King’s College London, said addressing this mix of “underlying beliefs, misleading information and harmful behaviour” was a challenge for public health.

“While they might seem outlandish, conspiracy suspicions and beliefs are far from harmless speculation – especially in the midst of a deadly pandemic,” he said.

“Our findings show that although conspiracy thinking is limited to a minority of the population, something which is important to emphasise, levels of belief are particularly high among certain groups, such as the vaccine-hesitant.

“Addressing this mix of underlying beliefs, misleading information and harmful behaviour is a key public health challenge.”