Instagram says it will block hashtags used to promote misinformation about vaccines.
Anti-vaccination messages on social media may be contributing to an increase in measles cases, according to the head of NHS England, Simon Stevens.
A spokesperson for Instagram told Sky News it had already blocked the hashtags #vaccinescauseautism, #vaccinescauseaids and #vaccinesarepoison.
The firm is now extending this policy to address hashtags that seem innocent on the surface.
For example, #vaccines1234 does not contain anything alarming in its wording.
But if it is found to be used in a number of posts to promote verifiably false vaccine misinformation it will be added to the block list.
However the social media giant has confirmed it will not be banning misinformation, as it was different from disinformation spread by a movement opposed to vaccines.
Nor will it be banning any accounts that promote or sharing the material, only the material itself.
The government recently announced plans to develop laws which would require web platforms to address harmful online content or face sanctions from an online harms regulator.
Despite calls to remove anti-vaccination messages, Instagram has claimed they don’t violate its policies and the platform can only attempt to reduce how many people see them.
The Instagram spokesperson said that verifiable hoaxes regarding vaccinations were being removed from Search, Explore and hashtag pages.
The charity Unicef has analysed data which shows that more than half a million children in the UK were not vaccinated against measles over an eight-year period.
Simon Stevens, chief executive of NHS England, said: “Getting yourself and your children vaccinated against killer diseases is essential to staying healthy, and vaccine rejection is a serious and growing public health time bomb.
“With measles cases almost quadrupling in England in just one year, it is grossly irresponsible for anybody to spread scare stories about vaccines, and social media firms should have a zero tolerance approach towards this dangerous content.”
Public Health England figures show there were 913 measles cases between January and October 2018, up from 259 in the whole of 2017.
The MMR (measles, mumps and rubella) vaccine take-up among five year-olds has fallen for five years in a row, with 87.2% of children vaccinated, below the World Health Organisation recommended level of 95%.
The medical establishment and available evidence are unanimous that vaccinations work, and that their value lies in mass uptake. For example, once measles uptake exceeds 95%, even those not vaccinated are effectively protected.
Yet the anti-vaccination movement has grown in recent years and is cited as a factor in alarming spikes in measles cases in the US, France and Italy.