Over half a million children in the UK were not immunised against measles between 2010 and 2017 - and now the number of people catching it is rocketing.
The head of the NHS in England has warned vaccine refusal is a “growing public health timebomb" with the contagious disease potentially causing brain damage, blindness and even death.
So what is fueling the decline in the number of MMR (measles, mumps, and rubella) vaccinations?
And is the anti-vax movement - the campaigners who believe that certain vaccines are not safe - to blame?
ITV News Video Producer Natalia Jorquera explains.
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