Final answer:
Chronic fatigue syndrome is the condition described, recognized as a chronic and contested illness with no single known cause and managed through a multifaceted approach.
Step-by-step explanation:
The condition being referred to in the question is chronic fatigue syndrome (CFS). This condition is often considered a contested illness because some medical professionals question whether it is a distinct disease or a collection of symptoms with multiple underlying causes. CFS is characterized as a chronic disease that persists over a long period and is associated with extreme fatigue that doesn't improve with rest and may worsen with physical or mental activity. Although there's no single known cause for CFS, it is understood that it may be triggered by various factors such as viral infections, stress, genetic predisposition, or a combination of influences. Management of CFS typically involves a multifaceted approach that can include medication, lifestyle changes, and psychological support.