What is ME?

Myalgic encephalomyelitis (ME), also known as chronic fatigue syndrome (CFS), is a serious, chronic, multisystem disease that affects millions of people worldwide. Despite its prevalence, ME remains poorly understood and severely underfunded.

Key Symptoms

The hallmark symptom of ME is post-exertional malaise (PEM) - a worsening of symptoms following even minor physical or mental exertion. This can last for days, weeks, or even months.


The NICE Guideline on ME/CFS lists the following symptoms all of which should be present for a diagnosis of ME/CFS:


Severity Levels

ME affects people to varying degrees:

Approximately 25% of people with ME are severely or very severely affected.

Diagnosis and Treatment

Currently, there is no diagnostic test for ME. Diagnosis is based on clinical criteria and ruling out other conditions. The NICE guideline on ME/CFS provides the most up-to-date guidance for healthcare professionals in the UK.

There is no cure for ME, and no treatments have been proven to be effective for all patients. Management focuses on:

The Impact

Based on the research carried out by Chris Ponting and Gemma Samms, University of Edinburgh, the estimated prevalence of people with a potential diagnosis of ME across the UK is 1.35 million, with women being disproportionately affected. The disease can affect people of all ages, including children.

The impact on individuals and families is profound, with many losing their careers, education opportunities, and social connections. 

This represents a considerable health burden on the NHS as well as a significant cost to the UK economy. The most recent report on the economic impact of ME was Counting the Cost published in 2017: this estimated the cost as £3.3 billion annually based on a 0.4% prevalence. Clearly the current economic impact will be significantly higher due to the increase in prevalence and cost burden. 

Why We Need Action

Despite decades of research, people with ME continue to face:

This is why MEAction UK campaigns for better recognition, research, and care for people with ME.