City health officials blasted parents after they were found encouraging their un-vaccinated kids to get the virus from each other in Brooklyn, New York.

The movement against the MMR vaccine, which protects against measles, mumps and rubella, is largely thought to stem from the work of Andrew Wakefield.

The now discredited UK doctor penned a damning research paper claiming a link between the MMR vaccine, autism and bowel disease.

The study was retracted in 2010 but the paper has had a lasting influence with the "anti-vaxxer" movement particularly taking off in America.

And the movement has sparked concern amid the current measles outbreak in New York – the largest the city has seen since 1991.

It is believed misguided parents are hosting "measles parties", encouraging their young, un-vaccinated children to spread measles with the idea that once a child has contracted it, they will be immune.