First report of swine-associated methicillin-resistant Staphylococcus aureus ST398 in Lithuania

Area of Science:

• Veterinary Microbiology
• Antimicrobial Resistance
• Food Safety

Background:

• Methicillin-resistant Staphylococcus aureus (MRSA) is a significant public health concern.
• Livestock, particularly pigs, can act as reservoirs for MRSA strains.
• Understanding MRSA epidemiology in food-producing animals is crucial for One Health approaches.

Purpose of the Study:

• To investigate the prevalence and characteristics of MRSA in pigs in Lithuania.
• To identify the specific MRSA strains, their genetic profiles, and antibiotic resistance patterns.

Main Methods:

• Nasal samples were collected from pigs on multiple farms in Lithuania.
• MRSA isolates were identified and characterized using microbiological and molecular techniques.
• Antibiotic susceptibility testing and genotypic analysis for resistance genes were performed.

Main Results:

• Four MRSA isolates belonging to ST398, spa type t011, and SCCmec V were identified.
• All isolates were resistant to tetracycline (tetK, tetM genes) and erythromycin (ermB gene).
• One isolate exhibited resistance to trimethoprim/sulfamethoxazole, carrying the dfrK gene.

Conclusions:

• This study reports the first detection of livestock-associated MRSA in pigs in Lithuania.
• The identified MRSA strains possess concerning antibiotic resistance profiles.
• Findings highlight the need for surveillance of MRSA in Lithuanian livestock.