Mashouf Rasoul Y, Hosseini Seyed M, Mousavi Seyed M, Arabestani Mohammad R
Department of Microbiology, Hamadan University of Medical Sciences, Hamadan, Iran.
Department of Microbiology, Hamadan University of Medical Sciences, Hamadan, Iran ; Brucellosis Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
Oman Med J. 2015 Jul;30(4):283-90. doi: 10.5001/omj.2015.56.
The aims of our study were to evaluate the prevalence of Staphylococcus aureus (S. aureus) strains in food samples of animal origin, examine their antibacterial susceptibility pattern, and to detect staphylococcal enterotoxin (SEs) genes and the mecA gene in isolated S. aureus strains using the polymerase chain reaction (PCR). .
A total of 1050 food samples including 671 raw milk and dairy products and 379 raw meats were collected between September 2013 and June 2014 in Hamadan, Iran. Food samples were analyzed for S. aureus identification. The antibiotic susceptibility pattern of all isolates was determined using the disk agar diffusion method followed by detecting mecA resistance gene using PCR. In addition, harboring of SE genes were determined using a multiplex PCR assay targeting nine genes. .
A total of 98 (9.3%) S. aureus strains were isolated from 1050 food samples. Of the 98 isolates examined, the most frequent resistance was observed to erythromycin (30.6%), followed by tetracycline (29.6%), gentamicin (27.6%), clindamycin (26.5%), ciprofloxacin and rifampin (24.5%), trimethoprim-sulfamethoxazole (14.3%), and cefoxitin (5.1%). All cefoxitin resistant isolates were positive for mecA. The prevalence of SEs was 77.6% (n=76). Among the genes that code classic enterotoxins, sea was the most frequent and was carried by 25.5% of isolates, followed by see in 18.4%, sed in 11.2%, sec in 5.1%, and seb in 4.1% of isolates. Among the detected enterotoxins, seg was the predominantly identified enterotoxin gene in isolates with prevalence of 35.7%. The seh gene with prevalence of 1% and sei gene with 3.1% were other detected enterotoxins with low frequencies. .
The high prevalence of SE genes detected indicates a potential risk for causing animal-originated food poisoning. The increasing prevalence of community-acquired MRSA and its emerging antibiotic resistance in foods is a serious problem for public health.
我们研究的目的是评估动物源性食品样本中金黄色葡萄球菌（S. aureus）菌株的流行情况，检测其抗菌药敏模式，并使用聚合酶链反应（PCR）检测分离出的金黄色葡萄球菌菌株中的葡萄球菌肠毒素（SEs）基因和mecA基因。
2013年9月至2014年6月期间，在伊朗哈马丹共采集了1050份食品样本，其中包括671份生乳及乳制品和379份生肉。对食品样本进行金黄色葡萄球菌鉴定分析。使用纸片琼脂扩散法确定所有分离株的抗生素药敏模式，随后通过PCR检测mecA耐药基因。此外，使用针对9个基因的多重PCR检测法确定SE基因的携带情况。
从1050份食品样本中总共分离出98株（9.3%）金黄色葡萄球菌菌株。在检测的98株分离株中，最常见的耐药情况是对红霉素（30.6%），其次是四环素（29.6%）、庆大霉素（27.6%）、克林霉素（26.5%）、环丙沙星和利福平（24.5%）、甲氧苄啶 - 磺胺甲恶唑（14.3%）以及头孢西丁（5.1%）。所有对头孢西丁耐药的分离株mecA均呈阳性。SEs的流行率为77.6%（n = 76）。在编码经典肠毒素的基因中，sea最为常见，25.5%的分离株携带该基因，其次是see（18.4%）、sed（11.2%）、sec（5.1%）和seb（4.1%）。在检测到的肠毒素中，seg是分离株中主要鉴定出的肠毒素基因，流行率为35.7%。seh基因流行率为1%，sei基因流行率为3.1%，是其他检测到的低频肠毒素。
检测到的SE基因高流行率表明存在引发动物源性食物中毒的潜在风险。社区获得性耐甲氧西林金黄色葡萄球菌的流行率增加及其在食品中出现的抗生素耐药性对公共卫生是一个严重问题。
