(selected excerpts below)...Within the last 5 to 10 years new ideas have been born in regard to underlying causes of the sporadic manifestation by the re-discovery of our microbial commensals as important factors of health and disease of human beings. A growing number of studies reports on altered oral or gut microbial communities in AD patients as compared to unaffected, cognitively normal age-matched controls. However, still only restricted consensus of findings arises from these studies: Ruminococcus and S24-7 seem to be occasionally decreased while Odoribacter, Blautia, and Alistipes have repeatedly been shown to be increased in gut microbiota of patients or rodent disease models (Endres, 2019)...