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.