Labour is calling on the government to bring in emergency laws to “stamp out dangerous” anti-vaccine content online.
In a letter, Labour said there should be financial and criminal penalties for social media firms that do not remove anti-vaccine fake news.
It comes after this week’s news that the world’s first effective Covid vaccine – made by Pfizer and BioNTech – had seen positive early results.
The government said it took the issue “extremely seriously”.
It said it had “secured a major commitment” from social media companies Facebook, Twitter and Google to tackle anti-vaccine content.
Suspicion of vaccines has been around almost as long as modern vaccines themselves.
But in recent years, the anti-vaccination – or “anti-vax”- movement has gained traction online. Social media has been blamed for allowing unfounded claims about vaccines to spread more easily.
In 2019, the UK lost its measles-free status designated by the World Health Organization – and there has been a marked decline in vaccination rates for all 13 diseases covered in jabs for children.
Since the pandemic, anti-vaccination campaigners have moved their focus to the coronavirus.
In the letter to Culture Secretary Oliver Dowden, Labour said there were dedicated anti-vaccination groups online with hundreds of thousands of followers who were “churning out disinformation” on the issue.
Shadow culture secretary Jo Stevens and shadow health secretary Jonathan Ashworth said the “spread of disinformation online presents a real and present danger” to the take-up of any potential vaccine.
“This is literally a matter of life and death and anyone who is dissuaded from being vaccinated because of this is one person too many,” said Ms Stevens.
Last week, the government announced that social media companies had agreed a package of measures – including that no company should be profiting from Covid vaccine fake news – and promising to act more quickly to respond to content flagged to them by the government.
But Labour warned that the measures don’t go far enough and has questioned why anti-vax groups are not being closed down.
“The announced collaboration with social media companies last week was welcome but feels grossly inadequate with a promise by them to remove only the content which is flagged by government and which generates profit,” said Labour.
Labour called for emergency legislation that would see financial and criminal penalties for a continued failure to act, and said they would vote for it.
On Monday, news of a potential vaccine made headlines after preliminary results from Pfizer and BioNTech showed their vaccine could prevent more than 90% of people from catching Covid.
The vaccine is one of 11 vaccines that are currently in the final stages of testing. Pfizer and BioNTech companies now plan to apply for emergency approval to use the vaccine by the end of November and a limited number of people may be given the vaccine this year.
The UK has bought enough doses for 20 million people.
But it will not be released for use in the UK until it passes final safety tests and gets the go-ahead from the MHRA – the Medicines and Healthcare products Regulatory Agency.
The head of the MHRA said this week it will not lower its safety standards despite the need to get a Covid vaccine quickly.
Earlier this year, Prime Minister Boris Johnson called people who oppose vaccinations “nuts”.
And this week, he said he had “no inhibitions” about getting one, adding: “Anti-vax is total nonsense, you should definitely get a vaccine.”
The government said: “Letting vaccine disinformation spread unchecked could cost British lives.
“We take this issue extremely seriously and have secured a major commitment from Facebook, Twitter and Google to tackle it by not profiting from such material, and by responding to flagged content more swiftly.
“We continue to work closely with social media firms to promote authoritative sources of information so people have access to vaccine facts not fiction.”