Threats across boundaries: the spread of ESBL-positive Enterobacteriaceae bacteria and challenge to "One Health" concept

Shaqiu Zhang ¹ Jing Yang ¹ Muhammad Abbas ² Qian Yang ¹ Qianlong Li ¹ Mafeng Liu ¹ Dekang Zhu ¹ Mingshu Wang ¹ Bin Tian ¹ Anchun Cheng ^1*

• ¹ Sichuan Agricultural University, Ya'an, Sichuan, China
• ² University of Surrey, Guildford, South East England, United Kingdom

β-lactam antibiotics are important drugs for humans. The spread of extended-spectrum βlactamase producing Enterobacteriaceae (ESBL-PE) exists globally in multiple reservoirs and the natural environment, and poses an immense threat to public health. Plasmid incompatibility groups such as IncFIA, IncI1, IncY, IncFIB, IncN, IncFIC, IncX4, IncB/O/K/Z, IncHI1/2, and IncA/C, are carrying blaCTX-M, blaTEM, and blaSHV genes in humans, animals, and the environment. The ISEcp1 upstream and orf477 downstream of blaCTX-M genes, as well as other mobile genetic elements (MGEs) such as IS903 and IS26, are involved in capturing and mobilizing antibiotic resistant genes (ARGs). The blaCTX-M-15 gene is most common among all discussed reservoirs. The environmental reservoir and propagation mode of ESBL-PE are growing and difficult to control. The reasons include but are not limited to bacterial adaptability and horizontal gene transfer (HGT) mediated by MGEs and plasmids. Conjugation is a pathway of HGT that is almost uncontrollable. MGEs and plasmids such as Tn3, IS1380 families, IncI1, IncK and IncN are facilitating HGT of blaCTX-M genes. This review highlighted the need to monitor trends in antimicrobial resistance (AMR) in the natural environment. Therefore, policies such as antibiotic management plans, training for healthcare providers and/or patients, cautious use of antibiotics, the need for epidemiological networks, pre-travel consultations, World Health Organization (WHO) infection control and biosafety guidelines, and other intervention measures are considered desirable.