Abstract
Pneumonia is a leading cause of morbidity and mortality in children, with bacterial pathogens being important etiologic agents. Most microbiome studies in pneumonia use technologies with limited taxonomical resolution and few include lung aspirate or blood samples. In this study, we assessed the microbial communities of the nasopharynx, nasopharynx/oropharynx, induced sputum, lung aspirate and blood, and recovered metagenome-assembled genomes from the same sites using shotgun metagenomics sequencing of samples from children with severe and very severe pneumonia in The Gambia. Our data show that Proteobacteria and Firmicutes were the most common phyla across the body sites, and this was largely driven by S. pneumoniae, H. influenzae/aegyptius and M. catarrhalis. Furthermore, we observed species overlap of blood and respiratory samples with average Jaccard similarity index values ranging from 34% to 58%. We recovered 60 medium and 35 high-quality MAGs in these niches including 11 S. pneumoniae , 10 H. influenzae strains and a limosilactobacillus with less than 95% Average Nucleotide Identity to any known species in GTDB-TK. We also showed that the resistomes in our MAGs were highly species specific with more than 70% of the detected AMR genes found exclusively in a single species.