Nasopharyngeal microbial dysbiosis in COVID-19 patients revealed by 16S metagenomics

During January and February of 2021, a total of 81 nasopharyngeal swab samples were collected from four distinct patient groups in the Central Greece region. Of these, 54 samples were obtained from patients who tested positive for the SARS-CoV-2 virus (PO), while the remaining 27 samples were from individuals who tested negative (NE). The PO patients were further categorized into three groups based on clinical criteria: severe (19, SE), mild (16, MI), and asymptomatic (19, AS). Following DNA extraction, the samples underwent 16S metagenomics sequencing on the Ion Torrent S5 platform to analyze their microbiomes.Significant differences were observed in alpha and beta diversity measures, with alpha diversity decreasing as COVID-19 severity increased. Each patient group exhibited distinct microbial profiles, except for the asymptomatic group, which displayed greater heterogeneity. Significant variations in the abundance of specific phyla, families, and genera were identified.