Air Microbiome Dynamics During the 2024 Boston Marathon

KATHERINE ARAYA, Vivian Tat, Sarah Alnemrat, Riley Watson, Madison Farnsworth, Justin Nguyen, Kostiantyn Botnar, Sean Kinahan, Shanna A. Ratnesar-Shumate, David Kimmel, Hema Narra, Christine Tomlinson, George Golovko, Kamil Khanipov, The University of Texas Medical Branch

     Abstract Number: 75
     Working Group: Bioaerosols

Abstract
Our air is a major medium for disease transmission, yet the dynamic ecosystem of microbial life that is present in the air —especially during mass gatherings— remains uncharacterized. We have collected aerosol samples from the 2024 Boston Marathon, a global event that attracted over 30,000 runners from more than 120 countries and approximately 500,000 spectators. We hypothesized the Boston Marathon induces detectable shifts in the air microbiome including the presence of antimicrobial resistance (AMR) genes. Aerosol samples before (N=4), during (N=4), and after (N=4) the marathon along the event route as well as background samples (N=7) were collected and analyzed to investigate the impact of mass human movement on the air microbiome. Bioaerosol samplers equipped with Teflon PTFE filter collected at a rate of 100 liters per minute for 24 hours at each location. DNA was extracted and isolated from the air filters using Zymo Biomics DNA miniprep kit and sequenced using Oxford Nanopore MinION P2Solo flow cell. Dorado super accurate model was used for basecalling. The workflow-metagenomics pipeline which utilized the core_nt database filtered at ≥90% identity to characterize the microbial community and presence of AMR genes. Results revealed significant differences in AMR gene presence in the air microbiome before versus after the marathon indicating an unhealthier environment for humans. The data strongly suggests that large-scale human movement in civilian mass events can disrupt airborne microbial ecosystems. The study’s findings have significant implications for the development of early warning systems such as targeted nanopore air surveillance protocols and subsequent targeted interventions. Future work will focus on health outcome patterns linked to this mass gathering event and analytical frameworks to further support proactive biosurveillance in diverse contexts. All data and bioinformatic pipelines will be made publicly available.