Development of Upper Respiratory Tract Microbiota in Infancy is Affected by Mode of Delivery

Abstract

Birth by Caesarian section is associated with short- and long-term respiratory morbidity. We hypothesized that mode of delivery affects the development of the respiratory microbiota, thereby altering its capacity to provide colonization resistance and consecutive pathobiont overgrowth and infections. Therefore, we longitudinally studied the impact of mode of delivery on the nasopharyngeal microbiota development from birth until six months of age in a healthy, unselected birth cohort of 102 children (n = 761 samples). Here, we show that the respiratory microbiota develops within one day from a variable mixed bacterial community towards a Streptococcus viridans-predominated profile, regardless of mode of delivery. Within the first week, rapid niche differentiation had occurred; initially with in most infants Staphylococcus aureus predominance, followed by differentiation towards Corynebacterium pseudodiphteriticum/ propinquum, Dolosigranulum pigrum, Moraxella catarrhalis/ nonliquefaciens, Streptococcus pneumoniae, and/or Haemophilus influenzae dominated communities. Infants born by Caesarian section showed a delay in overall development of respiratory microbiota profiles with specifically reduced colonization with health-associated commensals like Corynebacterium and Dolosigranulum, thereby possibly influencing respiratory health later in life.

Highlights

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  The respiratory microbiota is highly dynamic during the first six months of life.

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  The microbiota develops rapidly from a maternal/environmental-derived flora towards several niche-specific profiles.

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  Mode of delivery affects early respiratory microbiota development, especially colonization of potential protective commensals.

Birth by Caesarian section is associated with increased prevalence of respiratory diseases. We hypothesized that mode of delivery affects the micro-community of bacteria residing in the respiratory tract (microbiota), thereby influencing its ability to prevent invasion and outgrowth of potential pathogenic bacteria that can cause respiratory disease. We followed children during their first six months of life and show that the microbiota develops rapidly from a maternal/environmental-derived flora towards several niche-specific microbial profiles. Mode of delivery significantly affects respiratory microbiota development and interacts with breastfeeding, especially regarding the early presence of potential protective bacteria, which may contribute to respiratory health later in life.