This fatigue very much reduces the level of physical activity as well as disables much of the cognitive functions. So called nonspecific symptoms include sore throat, muscle aches and pains, excessive sleep, malaise, fever, tender lymp nodes, muscle weakness, balance problems and nausea. CFS can only be diagnosed by autopsy or by ruling out other disorders. There exists no treatment. The disease makes many people lose their jobs.
Social benefits are hard to get because the disease is often underestimated.
Even close friends and family might give up on patients. Either because they don't understand, or because they lack the resources for taking care. In bad cases patients can't even feed themselves. The disease is said not to be fatal. That might be true for most patients, but it's hard to believe that there are no exceptions to the rule.