Temporal dynamics of human respiratory and gut microbiomes during the course of COVID-19 in adults

Xu, R.; Lu, R.; Zhang, T.; Wu, Q.; Cai, W.; Han, X.; Jin, X.; Zhang, Z.; Zhang, C.; Wan, Z.

SARS-CoV-2 infects multiple organs including the respiratory tract and gut. Whether regional microbiomes are disturbed significantly to affect the disease progression of COVID-19 is largely unknown. To address this question, we performed cross-sectional and longitudinal analyses of throat and anal swabs from 35 COVID-19 adults and 15 controls by 16S rRNA gene sequencing. The results allowed a partitioning of patients into 3-4 categories (I-IV) with distinct microbial community types in both sites. Lower-diversity community types often appeared in the early phase of COVID-19, and synchronous fast restoration of both the respiratory and gut microbiomes from early dysbiosis towards late near-normal was observed in 6/8 mild COVID-19 adult patients despite they had a relatively slow clinical recovery. The synchronous shift of the community types was associated with significantly positive bacterial interactions between the respiratory tract and gut, possibly along the airway-gut axis. These findings reveal previously unknown interactions between respiratory and gut microbiomes, and suggest that modulations of regional microbiota might help to improve the recovery from COVID-19 in adult patients.