The debilitating long-term illness affects millions worldwide—including over 400,000 sufferers in the UK—but is poorly understood and has long lacked reliable diagnostic tools.

With 96% accuracy, the new test offers new hope for those living with the condition—which is often misunderstood and misdiagnosed. It is hoped that the breakthrough could pave the way for a similar blood test to diagnose long COVID.

Lead researcher Prof Dmitry Pshezhetskiy, from UEA’s Norwich Medical School, said, “ME/CFS is a serious and often disabling illness characterized by extreme fatigue that is not relieved by rest. We know that some patients report being ignored or even told that their illness is ‘all in their head.’ With no definitive tests, many patients have gone undiagnosed or misdiagnosed for years.