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Livestock associated-methicillin-resistant Staphylococcus aureus (LA-MRSA) has been emerging among pigs and pig handlers worldwide. This study aimed to determine the prevalence of LA-MRSA in pigs, workers and environment in Northern Thailand and to investigate phenotypic characteristics of LA-MRSA isolates. One hundred and four pig farms were randomly selected from the total of 21,152 pig farms in Chiang Mai and Lamphun provinces in 2012. Nasal and skin swab samples were collected from five pigs and two workers in each farm. As well, five environmental samples (pig stable floor, faucet and feeder) were collected using cotton swabs. MRSA was identified and confirmed by multiplex PCR from pooled samples of pigs, pig worker and farm environment. Phenotypic characterization of MRSA isolates were performed by Kirby-Bauer disk diffusion susceptibility test. The total of 104 pig farms and 138 workers were collected. The herd prevalence of MRSA was 8.65% (9 of 104 farms). The prevalence of MRSA in pigs, workers and the farm environment was 0.96%, 4.34% and 2.88%, respectively. Thirteen MRSA isolates were identified from eight workers, four isolates from environmental samples and one isolate from pigs. Ten of thirteen MRSA isolates were tested for antimicrobial resistance; these isolates were 100% resistant to clindamycin, cefoxitin, tetracycline, penicillin and sulfa-trimethoprim and 100% of all isolates showed multidrug resistant phenotype. This survey provided the first evidence of interrelationships for LA-MRSA among pigs, workers and the farm environment in Thailand. There was a low prevalence of MRSA in pigs, workers and the environment compared to other countries. Multi-drug resistant of MRSA isolates was observed. Further monitoring studies of MRSA in pig associated environment are required to detect changes in epidemiology and to implement effective control measures.