Fecal implants are probably the only effective way to recover human indigenous colonies. 60% of the stool's weight is intestinal flora. The flora recycle a lot. So, stool is rich in intestinal bacterias. Each individual gut microbiota is unique, it is like a finger print. But, the main bacterial colonies are the same for everybody. Native bacterias implant and multiply in the human gut. This could be a single solution for most of us.