Community-based household surface sampling: A citizen science approach for recovery of multidrug-resistant Enterobacterales.

Multidrug-resistant Enterobacterales are an increasing public health concern, yet household environmental sources remain poorly defined. This study evaluated whether citizen scientists can effectively collect household surface samples using sponge sticks to detect multidrug-resistant Enterobacterales and the effectiveness of methods of bacterial recovery from household surface types. We conducted controlled laboratory experiments using extended-spectrum beta-lactamase-producing Enterobacterales and extended-spectrum cephalosporin-resistant Acinetobacter baumannii on cloth, metal, and plastic surfaces to benchmark recovery efficiency. Recovery varied by organism, with highest rates for Klebsiella pneumoniae and A. baumannii, with minimal differences across surface types. Thirteen citizen-scientists sampled their household surfaces following standardized instructions. Bacteria were recovered from most households, including 16 Enterobacterales isolates resistant to third-generation cephalosporins. Recovered species included Escherichia coli, Pantoea agglomerans, and Enterobacter cloacae complex. Antibiotic susceptibility testing and PCR revealed diverse resistance patterns, including a multidrug-resistant E. coli carrying a blaCMY AmpC cephalosporinase gene. These findings demonstrate that citizen science-based sponge stick sampling is feasible and effective for detecting multidrug-resistant Enterobacterales in household environments. This approach provides a practical method for community-based antimicrobial resistance surveillance of gram-negative bacteria, enabling identification of household environmental reservoirs of multidrug-resistant Enterobacterales that, when paired with risk factor data, can inform targeted public health interventions and future epidemiological studies. Findings can be returned to participants through accessible summaries to promote community awareness and engagement in antimicrobial resistance prevention.