Distribution and influencing factors of Mycobacterium in rail transit based on metagenomic analysis

With the increasing prevalence of metro systems in urban transportation, there is a growing concern about the microbial pollution risks associated with these systems. To address this issue, this study employs metagenomic sequencing technology to investigate the distribution of Mycobacterium in aerosol samples collected from metro environments. Through the analysis of various environmental factors, insights into the factors influencing Mycobacterium contamination in metro systems are provided, aiming to offer evidence to support prevention and control measures against such pollution. In this study, a total of 90 species of Mycobacterium were detected in aerosol samples with a positivity rate of 30.77% including Mycobacterium tuberculosis that accounts for over 90% of the total abundance, as well as common opportunistic pathogens such as Mycobacterium gordonae, Mycobacterium avium, Mycobacterium intracellular, and Mycobacterium lentiflavum. Through correlation analysis, it was found that the distribution of Mycobacterium is related to season, temperature, CO2, PM1, PM2.5, and PM10 concentrations. In conclusion, it is recommended to adopt measures to control temperature and airborne concentrations of CO2 and particulate matter (PM1, PM2.5, and PM10) in order to minimize the risk of Mycobacterium contamination in metro systems. By implementing these recommendations, the prevention and control of Mycobacterium pollution can be effectively enhanced in the context of urban metros.