A nursery nurse leapt to her death after developing a sleep disorder caused “most likely” by a swine flu vaccination, a coroner has ruled.

Katie Clack, 23, began sleeping up to 19 hours per day while her mental health deteriorated after she received the vaccine in 2009.

In 2014, Ms Clack jumped to her death from a multi-storey car park in Peterborough after the condition – narcolepsy – caused her to become depressed.

Now a coroner has ruled the receipt of the vaccine likely caused the onset of the narcolepsy.