Over the last decade, it has become clear that respiratory and intestinal tract microbiota are related to pathogenesis of respiratory tract infections (RTIs). Host and environmental factors can drive respiratory microbiota maturation in early life, which in turn is related to consecutive susceptibility to RTIs. Moreover, during RTIs, including viral bronchiolitis, the local microbiome appears to play an immunomodulatory role through complex interactions, though causality has not yet been fully demonstrated. The microbiota is subsequently associated with recovery after RTIs and can be related to persistent or long-term sequelae. In this Review, we explore the epidemiological evidence supporting these associations and link to mechanistic insights. The long-term consequences of childhood RTIs and the comprehensive role of the microbiota at various stages in RTI pathogenesis call for early life preventative and therapeutic interventions to promote respiratory health.

在过去十年中，很明显呼吸道和肠道微生物群与呼吸道感染 (RTIs) 的发病机制有关。宿主和环境因素可以推动生命早期呼吸道微生物群的成熟，这反过来又与对 RTI 的连续易感性有关。此外，在包括病毒性细支气管炎在内的 RTIs 期间，局部微生物组似乎通过复杂的相互作用发挥免疫调节作用，尽管因果关系尚未完全证明。微生物群随后与 RTI 后的恢复有关，并且可能与持续或长期后遗症有关。在这篇综述中，我们探讨了支持这些关联的流行病学证据，并与机制见解相关联。