The head of NHS England has said “vaccination deniers” are gaining traction on social media as part of a “fake news” movement.

Simon Stevens said a parent at his own daughter’s primary school had used WhatsApp to express concern about children’s immune systems being “loaded up” with vaccines.

Speaking at a health summit organised by the Nuffield Trust, Stevens said the NHS was considering what action could be taken to help to stop the spread of anti-vaccination messages.

“One thing we are very concerned about at the moment is around... what is happening to vaccinations in this country,” he said. “Across the world, two to three million lives are saved each year by vaccination.

“But as part of the fake news movement, actually the vaccination deniers are getting some traction. Last year, for example, we saw more than triple the number of measles cases across England than we had seen the year before despite the fact that clearly vaccination works.

“We have seen a five-year steady decline in the vaccination uptake.”

He said there was a need to “win the public argument” around vaccines. “We are not being helped on this front by the fact that although nine in 10 parents support vaccination, half of them say they have seen fake messages about vaccination on social media,” he said.

Simon Stevens: ‘Two to three million lives are saved each year by vaccination.’ Photograph: Reuters

“There’s been a discussion even this week where I think Instagram has been under discussion, YouTube too.

“Frankly it’s as irresponsible to tell parents that their children shouldn’t be vaccinated as it is to say don’t bother - to your kids on their way to primary school - to look both ways when they cross the road. As a health service we’ve really got to help support parents on this.”

Stevens said parents at his daughter’s school had expressed concern about vaccines.

One message on WhatsApp from a parent at the school read:

“My kids aren’t vulnerable and I think loading up on vaccines blocks their systems from fighting disease as it should do.”

Stevens said: “We have a responsibility for the nine out of 10 to really explain it’s not just of interest for your own children but herd immunity for other children as well.

“The fact that the MMR for five-year-olds is 87.5% as against the 95% the WHO (World Health Organization) says it should be is a real problem.”

In January, the Royal Society for Public Health said social media was helping to spread “misleading and dangerous information” about vaccines.

Experts called for more to be done to challenge untruths about possible side-effects of vaccines and said social media giants should clamp down on “fake news”.

The study said social media is a “breeding ground for misleading information and negative messaging around vaccination”.

A Facebook spokesman said the company had “made significant investments in recent years to stop misinformation from spreading and to promote high-quality journalism and news literacy”.