College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road No. 211, Chengdu, 611130, Sichuan, China.
Chengdu Animal Disease Prevention and Control Center, Chengdu, 60041, Sichuan, China.
Braz J Microbiol. 2024 Mar;55(1):901-910. doi: 10.1007/s42770-023-01187-9. Epub 2023 Nov 24.
Sichuan is a significant aquaculture province in China, with a total aquaculture output of 1.72 × 10 tons in 2022. One of the most significant microorganisms hurting the Sichuan aquaculture is Aeromonas hydrophila, whose genotype and antibiotic resistance are yet unknown. This study isolated a total of 64 strains of A. hydrophila from various regions during September 2019 to June 2021 within Sichuan province, China. The technique of Multi-Locus Sequence Typing (MLST) was used for the purpose of molecular typing. Meanwhile, identification of antibiotic resistance phenotype and antibiotic resistance gene was performed. The findings of the study revealed that 64 isolates exhibited 29 sequence types (ST) throughout different regions in Sichuan, with 25 of these ST types being newly identified. Notably, the ST251 emerged as the predominant sequence type responsible for the pandemic. The resistance rate of isolated strains to roxithromycin was as high as 98.3%, followed by co-trimoxazole (87.5%), sulfafurazole (87.5%), imipenem (80%), amoxicillin (60%), and clindamycin (57.8%). Fifteen strains of A. hydrophila exhibited resistance to medicines across a minimum of three categories, suggesting the development of multidrug resistance in these isolates. A total of 63 ARGs were detected from the isolates, which mediated a range of antibiotic resistance mechanisms, with deactivation and efflux potentially serving as the primary mechanisms of antibiotic resistance. This study revealed the diversity of A. hydrophila genotypes and the risk of antibiotic resistance in Sichuan, providing reference for scientific and effective control of A. hydrophila infection.
四川是中国重要的水产养殖省份，2022 年水产养殖总产量达到 1.72×10^8 吨。危害四川水产养殖业的最重要的微生物之一是嗜水气单胞菌，其基因型和抗生素耐药性尚不清楚。本研究于 2019 年 9 月至 2021 年 6 月期间从中国四川省不同地区共分离出 64 株嗜水气单胞菌。采用多位点序列分型（MLST）技术进行分子分型。同时，进行了抗生素耐药表型和抗生素耐药基因的鉴定。研究结果表明，64 株分离株在四川不同地区表现出 29 种序列型（ST），其中 25 种为新发现的 ST 型。值得注意的是，ST251 是导致此次流行的主要序列型。分离株对罗红霉素的耐药率高达 98.3%，其次是复方新诺明（87.5%）、磺胺嘧啶（87.5%）、亚胺培南（80%）、阿莫西林（60%）和克林霉素（57.8%）。15 株嗜水气单胞菌对至少三类药物表现出耐药性，表明这些分离株存在多药耐药性。从分离株中检测到 63 种 ARGs，介导了多种抗生素耐药机制，失活和外排可能是抗生素耐药的主要机制。本研究揭示了四川嗜水气单胞菌基因型的多样性和抗生素耐药的风险，为嗜水气单胞菌感染的科学有效控制提供了参考。
