A study found that 404,000 people are living with the illness, two thirds more than previously thought, with a 50-fold variation in diagnosis rates

Researchers at the University of Edinburgh analysed NHS records from 62 million people to come up with the best estimate yet of the prevalence of ME, also known as chronic fatigue syndrome (CFS).

They concluded that 404,000 people are living with the illness, a figure that is two thirds higher than previously thought, and many are being “completely overlooked”.

Professor Chris Ponting, from the University of Edinburgh’s Institute of Genetics and Cancer, the study author, said: “The NHS data shows that getting a diagnosis of ME/CFS in England is a lottery, depending on where you live and your ethnicity. The data backs up what many people with ME/CFS say: that they feel invisible and ignored.”