Transmission of ceftazidime-avibactam-resistant Escherichia coli among pets,veterinarians and animal hospital environment

Ceftazidime-avibactam (CZA) is a recently approved combination synthetic β-lactamase inhibitor used in human clinical medicine. Cases of CZA resistance in humans have already been reported, but limited research has investigated CZA resistance in pets. This study explored the prevalence and transmission of CZA-resistant Escherichia coli (CZAREC) among pets, their owners, veterinarians, and the environment in animal hospitals. A total of 5,419 clinical samples were collected from dogs and cats, along with samples from the environment (n = 5,843), veterinarians (n = 557), and pet owners (n = 368) in animal hospitals. From these samples, 760 Escherichia coli (E. coli) isolates were obtained, out of which 60 were identified as CZAREC. These included 34 isolates from the environment (9.14 %, n = 372), three from veterinarians (8.11 %, n = 37), and 23 from animals (6.82 %, n = 337). No CZAREC isolates were found in pet owners. The predominant sequence types of CZARECs were ST156 (n = 20), ST410 (n = 19) and ST101 (n = 7). Bayesian analysis revealed six clusters comprising 47 isolates from the hospital environment, pets, and veterinaries, displaying genetic relatedness of less than 100 core genome single nucleotide polymorphisms (cgSNPs) between any two isolates in each cluster. Some CZAREC isolates with high genetic similarity persisted in the same animal hospital for four to six months. Moreover, discriminant analysis of principal components indicated that most isolates from different hosts shared a genetic source in the human/dog/cat merged cluster. Overall, evidence of CZARECs transmission was found among pets, the environment, and veterinarians in animal hospitals. The findings emphasize the importance of monitoring CZARECs in the veterinary clinical setting to ensure the health of both pets and humans.

China antimicrobial resistance surveillance network for pets(CARPet),2018 to 2021

China Antimicrobial Resistance Surveillance Network for Pets(CARPet)was established in 2021 to monitor the resist-ance profiles of clinical bacterial pathogens from companion animals.From 2018 to 2021,we recovered and tested 4,541 isolates from dogs and cats across 25 Chinese provinces,with Escherichia coli(18.5%)and Staphylococcus pseudintermedius(17.8%)being the most predominant bacterial species.The Enterobacterales were highly susceptible to tigecycline,meropenem,colistin,and amikacin(70.3%-100.0%),but showed moderate resistance to ampicillin,ceftriaxone,doxycycline,florfenicol,levofloxacin,enrofloxacin,and trimethoprim-sulfamethoxazole(29.3%-56.7%).About 66.3%of Acinetobacter spp.were resistant to florfenicol,with relatively low resistance to another 11 antibiot-ics(1.2%-23.3%).The Pseudomonas spp.showed high susceptibility to colistin(91.7%)and meropenem(88.3%).The coagulase-positive Staphylococcus spp.showed higher resistance rates to most antimicrobial agents than coagulase-negative Staphylococcus isolates.However,over 90.0%of Staphylococcus spp.were susceptible to linezolid,dapto-mycin and rifampin,and no vancomycin-resistant isolates were detected.E.faecium isolates demonstrated higher resistance rates to most antimicrobial agents than E.faecalis isolates.Streptococcus spp.isolates showed low resistance to most antimicrobial agents except for doxycycline(78.2%)and azithromycin(68.8%).Overall,the tested clinical isolates showed high rates of resistance to commonly used antimicrobial agents in companion animals.Therefore,it is crucial to strengthen the monitoring of bacterial resistance in pets.By timely and effectively collecting,analyzing,and reporting antimicrobial resistance dynamics in pets,the CARPet network will become a powerful platform to provide scientific guidance for both pet medical care and public health.