Isolation and molecular characterization of methicillin-resistant staphylococci from horses, personnel and environmental sites at an equine hospital in Turkey.

The research article examines the prevalence of methicillin-resistant staphylococci in racehorses, veterinary staff, and environmental surfaces at an equine hospital in Turkey. The study also investigated specifics like species distribution, antibiotic resistance, resistance genes, the type of staphylococcal chromosomal cassettes and clonality of these samples.

Identification and Frequency of MRS

• The study focused on determining the occurrence of methicillin-resistant staphylococci (MRS) among racehorses, veterinary personnel, and environmental surfaces at an equine hospital in Turkey.
• The study involved 209 racehorses, 13 personnel, and 14 environmental sampling sites.
• The researchers identified MRS using 16S rRNA sequencing, a crucial tool in microbial identification, and typing was done using pulsed-field gel electrophoresis (PFGE), a lab technique often used in epidemiology studies for tracking the source of an outbreak.
• The findings revealed a high incidence of MRS among horses (48.3%), clinic staff (92.3%), and environmental samples (71.4%).

Species Distribution

• Out of the 123 MRS isolates, the majority were identified as Staphylococcus lentus (118 instances).
• The remaining five were identified as S. sciuri (3 instances), S. intermedius (1 instance), and S. fleuretti (1 instance).

Antibiotic Resistance

• All isolated MRS were found to be resistant to methicillin but susceptible to vancomycin, quinupristin-dalfopristin, and rifampicin, three other kinds of commonly-used antibiotics.
• The research also found that single or various combinations of resistance genes were detected among the MRS isolates, suggesting different levels of resistance.

Staphylococcal Chromosomal Cassette (SCCmec) and Clonality

• SCCmec type II was identified in all the isolates, suggesting a common resistance mechanism among them.
• Using PFGE patterns, the researchers found similarities among MRS isolated from horses, humans, and environmental samples, indicating potential cross-transmission.

Possible Transmission of MRS

• The simultaneous presence of MRS in both horses and humans suggests the potential for cross-transmission between the two groups.
• However, the study does not definitively conclude whether the transmission is from human to animal or vice versa.