Bifidobacteria, from mother to child


Bifidobacteria are among the first bacteria to colonize the intestine in newborns, and are transmitted from the mother during birth and breastfeeding.


Italian researchers have demonstrated precisely that by describing this bacterial group in 25 mother-child pairs. The genus Bifidobacterium plays an important role in establishing the intestinal flora, innate immunity, and the functioning of the mucosa. To understand how these bacteria colonize newborns’ gastrointestinal tracts, researchers analyzed their presence in the mother’s fecal flora at the time of birth and in the newborn’s stool at one week and one month after birth, and in the breast milk. They confirmed a true vertical transfer, with strains present in the mother found in the baby’s gastrointestinal flora. Furthermore, breastfeeding seemed to facilitate that colonization. The milk effectively served as a vehicle for bifidobacteria like B. bifidum that can metabolize the sugars present in it, allowing other species of bifidobacteria to implant themselves in the intestine by consuming the sugar by-products. Lastly, the researchers noted that this transfer also applied to bifidophages, bacteriophages that specifically target the Bifidobacterium genus already described in adults and infants, and which may contribute massively to shaping the intestinal microbiota of the latter.


Duranti S et al. Maternal inheritance of bifidobacterial communities and bifidophages in infants through vertical transmission. Microbiome (2017) 5:66