A systematic review of enteric pathogens and antibiotic resistance genes in extramural urban aerosols

Abstract

SUMMARYBackgroundAerosol transport of enteric microbiota including fecal pathogens and antimicrobial resistance genes (ARGs) has been documented in a range of settings but remains poorly understood outside indoor environments.MethodsWe conducted a PRISMA-adhering systematic review of the peer-reviewed literature to summarize evidence on specific enteric pathogens and ARGs that have been measured in aerosol samples in urban settings where the risks of extramural exposure and antibiotic resistance (AR) spread may be highest. We conducted a key word search for articles published within the years 1990-2020 using relevant data sources. Two authors independently conducted the keyword searches in all aforementioned databases and conducted primary and secondary screenings before merging results. To be included, studies contained extractable data on enteric pathogens and AR in extramural aerosols, identified urban related sources if any and reported on qualitative, quantitative, or viability data that was sufficient for interpretation within the three aforementioned groups.FindingsQualitative analyses and metric summaries revealed that enteric microbes and antibiotic resistance have been consistently reported in extramural aerosols, generally via relative abundance measures, though gaps remain preventing full understanding of the role of the aeromicrobiological pathway in the fate and transport of enteric associated extramural aerosols.InterpretationWe identified remaining gaps in the evidence base including a need for broad characterization of enteric pathogens in bioaerosols beyond bacterial genera, a need for greater sampling in locations of high enteric disease risk, and a need for quantitative estimation of microbial and nucleic acid densities that may be applied to fate and transport models and in quantitative microbial risk assessment.FundingThis study was funded by the National Science Foundation under grant number 1653226. This funding source had no role in the design of this study and had no role during its execution, analyses, interpretation of the data, or decision to submit results.