Changes in the Population of Methicillin-Resistant Staphylococcus pseudintermedius and Dissemination of...

Area of Science:

• Veterinary Microbiology
• Canine Infectious Diseases
• Antimicrobial Resistance

Background:

• Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is a growing global threat to canine health.
• Understanding MRSP's temporal distribution, resistance patterns, and clinical links is crucial for managing its spread.
• Canine pyoderma, wound infections, and otitis externa are common conditions associated with MRSP.

Purpose of the Study:

• To analyze the yearly prevalence of MRSP lineages and their antimicrobial resistance phenotypes in the Netherlands.
• To investigate the association between MRSP and specific clinical conditions in dogs.
• To track the emergence and evolution of MRSP in the canine population.

Main Methods:

• Isolation and identification of MRSP from canine diagnostic samples.
• Multilocus sequence typing (MLST) to characterize MRSP lineages (sequence types and clonal complexes).
• Antimicrobial resistance profiling of MRSP isolates.

Main Results:

• The annual incidence of MRSP in canine samples rose from 0.9% in 2004 to 7% in 2013.
• CC71 emerged as the predominant MRSP lineage, with other lineages like CC258 becoming more frequent later.
• Nearly all MRSP strains exhibited multidrug resistance (MDR), though CC258 and singleton strains showed lower resistance levels.

Conclusions:

• Multidrug-resistant CC71 MRSP emerged as the dominant lineage in Dutch dogs from 2004 onwards.
• A shift towards less resistant MRSP lineages is occurring, potentially replacing the dominant CC71.
• Continued surveillance is necessary to monitor MRSP evolution and its impact on canine health.