One Health Approach of Enterococcal Population Structure and Antibacterial Resistance Along the Food Chain - Four PLADs, China, 2015-2022.

INTRODUCTION

Enterococci are considered opportunistic pathogens. However, they can serve as a reservoir of antibacterial resistance (ABR) traits and transfer these to humans through the food chain.

METHODS

Antibiotic susceptibility testing and multilocus sequence typing were used to characterize the ABR and population structure of 488 enterococcal isolates recovered along the food chain from four provincial-level administrative divisions (PLADs) in China.

RESULTS

() was the dominant species cultured from pig farms and retail meat, while () and were dominant in patients with diarrhea and retail fruits and vegetables, respectively. Approximately 67% of all isolates were multidrug-resistant (MDR). resistance to ampicillin and penicillin was significantly higher than that of . The isolates exhibited substantially heterologous sequence types (STs), whereas isolates were clearly divided into clonal complex (CC) CC17 and CC94 clades. isolates were mainly detected in hospitalized children and were identified as the hospital-associated CC17 clade with ampicillin and penicillin resistance. Notably, ST16 and ST65 and ST60 and ST94 detected in patients with diarrhea were also detected in farm and food samples, indicating that these STs should be closely monitored. The community-lineage CC94 clade was detected in patients with diarrhea, implying that community isolates might find their way into hospitals.

CONCLUSION

This study highlights the One Health challenges posed by enterococci important to human health and the need to implement integrated preventive measures for their control.