Prevalence and Genetic Characterization of Methicillin-Resistant Staphylococcus aureus Isolated from Pigs in Japan

Autor: Michiko Kawanishi, Mari Matsuda, Hitoshi Abo, Manao Ozawa, Yuta Hosoi, Yukari Hiraoka, Saki Harada, Mio Kumakawa, Hideto Sekiguchi
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Antibiotics, Vol 13, Iss 2, p 155 (2024)
Druh dokumentu: article
ISSN: 2079-6382
DOI: 10.3390/antibiotics13020155
Popis: We investigated the prevalence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in pig slaughterhouses from 2018 to 2022 in Japan and the isolates were examined for antimicrobial susceptibility and genetic characteristics by whole-genome analysis. Although the positive LA-MRSA rates on farms (29.6%) and samples (9.9%) in 2022 in Japan remained lower than those observed in European countries exhibiting extremely high rates of confirmed human LA-MRSA infections, these rates showed a gradually increasing trend over five years. The ST398/t034 strain was predominant, followed by ST5/t002, and differences were identified between ST398 and ST5 in terms of antimicrobial susceptibility and the resistance genes carried. Notably, LA-MRSA possessed resistance genes toward many antimicrobial classes, with 91.4% of the ST398 strains harboring zinc resistance genes. These findings indicate that the co-selection pressure associated with multidrug and zinc resistance may have contributed markedly to LA-MRSA persistence. SNP analysis revealed that ST398 and ST5 of swine origin were classified into a different cluster of MRSA from humans, showing the same ST in Japan and lacking the immune evasion genes (scn, sak, or chp). Although swine-origin LA-MRSA is currently unlikely to spread to humans and become a problem in current clinical practice, preventing its dissemination requires using antimicrobials prudently, limiting zinc utilization to the minimum required nutrient, and practicing fundamental hygiene measures.
Databáze: Directory of Open Access Journals