Dados do Trabalho

Título

Exploring the Multidrug Resistance Landscape of Bovine-associated Staphylococcus aureus from a One Health Perspective

Introdução

Staphylococcus aureus poses a significant threat to bovine udder health, with unquestionable importance in human and veterinary medicine, due to rising antimicrobial resistance. This pathogen is a leading cause of bovine mastitis, which is responsible for up to 70% of antimicrobial use on dairy farms. Furthermore, cows are the primary animal reservoir for the emergence of S. aureus human epidemic clones, demanding a comprehensive One Health approach. Understanding the antimicrobial resistance profiles of S. aureus strains isolated from dairy herds is crucial for developing effective antimicrobial strategy.       

Objetivo (s)

Thus, this study aimed to explore the relationship between the antimicrobial resistance profiles of bovine-associated S. aureus and clonal diversity, herd origin, and host origins.

Material e Métodos

This study, approved by the UFMG Bioethics Committee, obtained 212 S. aureus isolates (197 from subclinical mastitis, 9 from clinical mastitis, and 6 from nasal swabs) from four commercial dairy herds with high S. aureus mastitis prevalence. All S. aureus isolates were identified by MALDI-ToF MS and PCR targeting the nuclease gene. S. aureus spa typing involves amplifying the polymorphic X region of the protein A gene. Methicillin-resistant S. aureus (MRSA) was identified using the disk diffusion method and PCR for the mecA and mecC genes. Susceptibility to 10 antimicrobials, including critically important ones, was determined by the Minimum Inhibitory Concentration method.  Multidrug resistance was defined as resistance to three or more antimicrobial classes (excluding ampicillin). The associations among the origins of S. aureus, herds, and multidrug resistance were explored using the Fisher exact and Chi-squared tests.  

Resultados e Conclusão

Our study reveals an alarming 19.34% of staphylococci isolates are multidrug-resistant identified in six of the 15 spa types identified. Here, spa type t267 was significantly associated with non-multidrug-resistant profile (P < 0.0001), while spa type t6861 showed a higher multidrug-resistant profile (P = 0.03). Furthermore, herds A and C exhibited a higher percentage of multidrug-resistant isolates compared to herd B (P < 0.0005). We found no association between multidrug-resistant profiles and staphylococci origin. Thus, this study underscores the need for continuous surveillance of antibiotic resistance in staphylococci to curb the spread of multidrug-resistant strains.  

Palavras Chave

Staphylococci; mastitis; antimicrobial resistance; antibiotic usage; One health.