The term ‘microbiome’ refers to the collective genomes of these microorganisms. The microbiome is often referenced instead of the microbiota, probably because much of our understanding of these bodily inhabitants has been derived from 16S rRNA and metagenomics, which have provided information for the genomic study of these microorganisms (many of which have proven difficult to isolate and culture). The human microbiota is estimated to contain 10–100 trillion microbial cells, and the intestinal microbiota accounts for the largest and most diverse population. Side effects may include a risk of infections, therefore the donor should be screened. FMT involves restoration of the colonic microflora by introducing healthy bacterial flora through infusion of stool via colonoscopy, enema, orogastric tube, or by mouth in the form of a capsule containing feces from a healthy donor, which in some cases is freeze-dried. Fecal transplantation is performed as a treatment for recurrent C. difficile colitis. C. difficile colitis, a complication of antibiotic therapy, may be associated with diarrhea, abdominal cramping and sometimes fever. If you are over the age of 65 and/or have chronic illnesses, you may be at higher risk for having more severe infection. Diagnosis is based on a stool DNA test that detects the organism.