Prevalence and antimicrobial resistance of Acinetobacter baumannii in the livestock industry in South Korea under a One Health perspective
Yeon Soo Chung, Eun Jung Sohn, Hyeonwoo Cho, Beomsoon Jang, Miru Lee, Soo‐Jin Yang, Kun Taek Park
Abstract
The emergence and global spread of the antimicrobial-resistant Acinetobacter baumannii pose a significant public health challenge. Despite extensive research on clinical isolates, data on A. baumannii outside of hospital settings, particularly in livestock, remain limited. This study aimed to investigate the prevalence, antimicrobial resistance, and molecular characteristics of A. baumannii within the livestock production chain in South Korea, including farms, slaughterhouses, and markets. A total of 2940 samples were collected from pig- and cattle-associated sources, including animals, workers, carcasses, meat, and environmental sources. A. baumannii was isolated from 3.1 % of pig-associated samples ( n = 50) and 7.0 % of cattle-associated samples ( n = 92), with the highest prevalence observed during slaughter. None of the pig-associated isolates showed resistance to the tested antimicrobials, whereas 8.7 % ( n = 8) of the cattle-associated isolates showed resistance to one or two antimicrobial agents. Multi-locus sequence typing using the ‘Oxford’ scheme revealed 64 distinct sequence types (STs) among the isolates, of which 42 were novel STs first reported in this study. Notably, the STs of four antimicrobial resistant A. baumannii isolates (ST2292, ST3476, ST3477, and ST3482) were genetically related to international human clinical clones. Although A. baumannii appears to be a transient colonizer rather than a primary resident of livestock, its presence in the food production chain poses transmission risks to humans via occupational exposure or food supply. These results highlight the necessity of a One Health-based surveillance to track the emergence of novel A. baumannii strains in the livestock sector. Research into genomic epidemiology, environmental reservoirs, and transmission dynamics remains warranted to gain deeper insights into the role of A. baumannii in the interconnected human-animal-environment interface.