Distinct Gut Microbiota in Southeastern African and Northern European Infants

BACKGROUND AND OBJECTIVE: The intestinal microbiota composition in infants reflects the early environment. Our objective was to compare the gut microbiota in 6-month-old infants living in rural Malawi with children of the same age living in urban Finland, both being breast-fed and having an age-appropriate diet typical for each area. METHODS: Malawian 6-month-old infants (n=44) were compared with Finnish infants (n=31) of the same age. In both cohorts, infant stool samples were available for microbiota characterization by flow cytometry-fluorescent in situ hybridization and quantitative polymerase chain reaction methods. RESULTS: Bifidobacteria were dominant at 6 months of age in all of the infants, although in greater proportions in Malawian (70.8%) than in Finnish infants (46.8%; P<0.001). Additional distinctions in bacterial group composition comprised Bacteroides-Prevotella (17.2% vs 4.7%; P<0.001) and Clostridium histolyticum (4.4% vs 2.8%; P=0.01), respectively. The species Bifidobacterium adolescentis, Clostridium perfringens, and Staphylococcus aureus were absent in Malawian but detected in Finnish infants. CONCLUSIONS: The gut microbiota of 6-month-old infants in a low-income country differs significantly from that in a high-income country. This may have an effect on both the energy harvest from the diet typifying malnutrition and diarrheal diseases in low-income countries and Western lifestyle diseases in high-income countries.