Pupils could be banned from school if their parents refuse to give them the measles jab, the health secretary has warned.
Matt Hancock suggested he was considering the extreme move after Unicef revealed more than half a million UK kids have not had their MMR jab.
Cases of deadly measles virus have increased almost four-fold in England over the past year following a fall in uptake.
False stories suggesting vaccination causes harms have become common on the internet.
This growing “anti-vax” movement is thought to be to blame for parents not giving their children the jab.
Mr Hancock pointed the finger at social media giants such as Facebook and YouTube, telling the BBC Radio 4 today programme: “I’m not relaxed about this at all.
“One of the things I am particularly worried about is the spread of anti-vaccination messages online.
“Vaccination is safe, it’s very, very important for the public health – for everybody’s health – and we’re going to tackle it.”
He was asked on Talk Radio if children should be banned from school unless they are vaccinated.
Host Julia Hartley-Brewer asked if he’d consider meeting the Education Secretary, Damian Hinds, to discuss “following in the footsteps” of France and the US.
He replied: “I wouldn’t rule out anything but I don’t think we’re there yet.
“In America they tried to do this and the courts stopped them so it can be complicated, but really it’s people’s responsibility as a parent to do the right thing – the right thing for their own children as well as, of course, the right of the community that everybody lives in.”
Mr Hancock revealed he will meet social media firms on Monday to demand they “do more to take down lies” promoted on their sites.
He said: “I have called in the social media companies, like we had to with self-harming images a few months ago.
“I’m seeing them on Monday to require that they do more to take down lies that are promoted on social media about the impact of vaccination.”
Children should have two doses of the jab to be protected, with the World Health Organisation setting a target of 95% coverage.
Unicef estimate 169 million children worldwide missed the first dose of the measles jab between 2010 and 2017, with 527,000 in the UK.
Uptake of both jabs by the age of five has fallen in England for four years in a row, from 88.6% in 2014-15 to 87.2% in 2017-18.
There were 259 measles cases in England in 2017, rising to 966 in 2018.
Measles is a highly infectious viral illness that can lead to serious health complications, including infections of the lungs, eyes and brain. In one in 25,000 cases, brain complications can be fatal.
Babies and children with weakened immune systems are most at risk of complications. More common ones include diarrhoea and vomiting, lung infections and fits caused by a fever.
In many countries including the UK, the MMR vaccine protects against measles, mumps and rubella – or German measles.
The second dose is given to children before starting school, when three to four years old
When the Prime Minister Theresa May’s official spokesman was asked whether children who have not been vaccinated for measles should be excluded from schools, she said: “I haven’t seen anyone suggesting that.
“The overall risk of measles to the UK population is very low. The World Health Organisation said the UK achieved measles elimination status as recently as 2017.
“Overall vaccine uptake is also very high, at over 90%, but we are continuously working to drive up immunisation rates.
“We are reviewing the slight decline in uptake as part of the long-term plan for the NHS to push coverage even higher and Public Health England are developing new campaigns about the benefits of immunisation.”
A Government spokesperson said: “We ask schools to check what immunisations a child has had when they join a school but our guidance clearly states that schools cannot refuse admission or exclude a pupil because they have not been immunised.
“Overall uptake of childhood vaccinations is over 90%.
“While not compulsory, it is important everyone takes up the vaccinations they are entitled to, so we are focused on ensuring parents and children know the facts about their benefits and on working with social media companies to stop the spread of misinformation around vaccinations.
“We are also reviewing how to improve vaccine uptake overall as part of our Long Term Plan for the NHS.”
