Chronic fatigue syndrome (CFS), also referred to as myalgic encephalomyelitis (ME), is a medical condition characterised by long-term fatigue and other persistent symptoms that limit a person’s ability to carry out ordinary daily activities.  Other symptoms may include difficulty with thinking or memory, difficulty with sitting or standing, muscle pain, headache, tender lymph nodes in the neck or armpits, recurring sore throat, digestive issues, night sweats, or sensitivities to foods, chemicals, or noise.  Symptoms may develop gradually or suddenly, and are often worsened by normal physical or mental activity.