School-aged children, Respiratory infection, Mycoplasma pneumoniae, Viral metagenomics, Respiratory virome, Infectious and parasitic diseases, RC109-216

Abstract Background Mycoplasma pneumoniae (MP) is a common pathogen for respiratory infections in children. Previous studies have reported respiratory tract microbial disturbances associated with MP infection (MPI); however, since the COVID-19 pandemic, respiratory virome data in school-aged children with MPI remains insufficient. This study aims to explore the changes in the respiratory virome caused by MPI after the COVID-19 pandemic to enrich local epidemiological data. Methods Clinical samples from 70 children with MPI (70 throat swab samples and 70 bronchoalveolar lavage fluid (BALF) samples) and 78 healthy controls (78 throat swab samples) were analyzed using viral metagenomics. Virus reads were calculated and normalized using MEGAN.6, followed by statistical analysis. Results Principal Coordinate Analysis (PCoA) showed that viral community diversity is a significant difference between disease cohorts and healthy controls. After MPI, the number of virus species in the upper respiratory tract (URT) increased obviously, and the abundance of families Poxviridae, Retroviridae, and Iridoviridae, which infect vertebrates, rose evidently, particularly the species BeAn 58,085 virus (BAV). Meanwhile, phage alterations in the disease cohorts were predominantly characterized by increased Myoviridae and Ackermannviridae families and decreased Siphoviridae and Salasmaviridae families (p