Patients with chronic fatigue syndrome (CFS) and their healthy family members (living together in the same house) are recruited in the study. CFS has been diagnosed in Tampere University Hospital and the diagnosis is based on thorough clinical assessment fulfilling the Institute of Medicine 2015 criteria. Patients microbiota is analyzed (microbiological analysis, mediators of inflammation) and results are compared with their family members.~Via colonoscopy, up to 40 patients with CFS are randomized to receive either a faecal transplant from a healthy donor (treatment group) or his/her own feces (placebo group). Products are blinded, investigators and patients are blinded. Patients' health related quality of life and ability to work or study are assessed (baseline, 1 and 6 months after the procedure).
Gut microbiota of 1) patients with chronic fatigue syndrome and 2) their healthy family members are analyzed.~Up to 40 patients with chronic fatigue syndrome are randomized to receive either 1) a faecal transplant from a healthty donor or 2) their own feces via colonoscopy. Patient's health related quality and ability to work are assessed (baseline, 1 and 6 months after the procedure)