Composition characteristics of the gut microbiota in infants and young children of under 6 years old between Beijing and Japan

Background The composition of intestinal flora in Chinese and Japanese has been reported in many studies but that in infants aged 0-6 years old has not been studied yet. Methods The distribution characteristics of the fecal flora of infants in Beijing (n=84) and Japan (n=53) were analyzed using 16S rRNA gene sequencing analysis. Results This study showed the higher relative abundance of Erysipelotrichaceae_ UCG-003 and Anaerostipes in male group that of Ruminiclostridium, Eubacterium, Senegalimassilia and Senegalimassilia in female group, especially Senegalimassilia, which was not detected in male group. Defecation trait groups indicated significantly higher relative abundance of Bifidobacterium in abnormal bowel trait group than that in the normal group (P<0.05). The feeding groups' analysis showed significantly higher relative abundance of Bifidobacterium and Enterococcus and lower abundance of Bacteroides and Lacetospirillaceae in the breast-feeding group than that in the formula feeding and mixed-feeding groups. The relative abundance of Parasutterella and Ruminococcaceae_UCG-003 in the halitosis group was significantly higher than that in the normal group. The comparison of cold and fever group and normal group indicated significantly higher relative abundance of Erysipelatoclostridium and lower relative abundance of Lachnospiraceae _UCG-001 in the fever and cold group than that in the normal group (P<0.05). The regional comparison of intestinal flora of Beijing and Japan showed significant increase in the relative abundance of Bacillus, Lactobacillus, Prevotella, megamonas and Veillonella in the intestinal flora of 0-6 years old infants in Beijing. Conclusions These findings improve the understanding of intestinal bacterial and viral communities of infants from the two Asian countries.