<i>spa</i> Typing and Antibiotic Resistance Profiles of Methicillin‐Resistant <i>Staphylococcus aureus</i> Isolates From Broilers in Ilam, Iran

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant threat to public health and the poultry industry due to its resistance to β-lactam antibiotics and its potential for transmission between animals and humans. OBJECTIVES: This study aimed to characterize MRSA isolates from broilers in Ilam, Iran, utilizing spa typing and evaluating their antibiotic resistance profiles. METHODS: A total of 200 samples were collected from nasal and cloacal swabs of broilers. Bacterial isolation and biochemical tests were conducted. The presence of S. aureus was confirmed through polymerase chain reaction (PCR) targeting the femA gene. PCR amplification of the mecA gene was performed to identify MRSA. Additionally, the spa gene was amplified in all identified MRSA strains and in one representative strain of methicillin-sensitive Staphylococcus aureus (MSSA). Antibiotic susceptibility testing was conducted on all 107 S. aureus isolates. RESULTS: A total of 237 bacterial strains were isolated. Of the 107 confirmed S. aureus isolates, 9 (8.41%) were identified as MRSA. spa typing revealed five distinct types, including four for MRSA and one for MSSA. Notably, three novel spa types (t304, t567 and t1184) were reported for the first time in Iran, reflecting unique local adaptations, with t011 (40%) being the most common. CONCLUSIONS: This study underscores the genetic diversity of MRSA in poultry and highlights the urgent need for effective control measures to combat antibiotic resistance.