Harakeh Steve, Yassine Hadi, Gharios Maya, Barbour Elie, Hajjar Shadi, El-Fadel Mutasem, Toufeili Imad, Tannous Raja
Department of Biology, American University of Beirut, PO Box 11-0236, Beirut, Lebanon.
Sci Total Environ. 2005 Apr 1;341(1-3):33-44. doi: 10.1016/j.scitotenv.2004.09.025.
The aim of this study was to characterize at the molecular level the different stains of Salmonella spp. and Escherichia coli that were isolated from meat-based fast food in Lebanon. In addition, this study evaluated the resistance of those strains to different antimicrobials that are commonly used. The foods included were Lahm-bi-Ajeen (LBA, meat pies) and Shawarma (Lebanese meat sandwiches similar to Gyros and Donairs, containing meat, vegetables, and sesame seeds-oil-based sauce). Polymerase chain reaction (PCR) was used to characterize and identify the strains of both bacteria. Salmonella species characterization was performed using rfb genes cluster genetic marker, while that of E. coli strains were carried out based on stx1, stx2, eaeA, fliC, and ehlyA virulence markers. The characterized strains were then tested for their response to various antimicrobials. The results showed that the tested foods were contaminated with Salmonella paratyphi (serogroup A) and Shiga Toxin (Stx)-producing E. coli (STX-EC). The PCR showed that 75% of E. coli tested strains was positive in PCR performed with stx1 primers, one of which was eaeA positive. Two of the tested strains were positive using PCR with fliC primers. The resistances of the various strains were evaluated using the following antimicrobials: Oxacillin, Teicoplanin, Trimethoprim/sulfamethoxazole, Gentamicin, Clindamycin, Cefotaxime, Cefuroxime, Erythromycin, and Vancomycin. Bacteria were highly resistant to one or more of the tested antimicrobials. Approximately 69% of E. coli and 77.8% of Salmonella spp. exhibited resistance. Salmonella spp. were shown to be 100% resistant to four antimicrobials: Oxacillin, Teicoplanin, Clindamycin, Vancomycin, and Erythromycin, while E. coli was 100% resistant to Teicoplanin and Trimethoprim/sulfamethoxazole. The most interesting findings were the high susceptibility of the E. coli to Gentamicin (100%). Highest resistance in the case of Salmonella spp. was seen against Cefotaxime (74%). Those two antimicrobials are commonly used for the treatment of enteric infections caused by gram-negative bacteria. The results showed that meat-based fast foods in Lebanon could be a public health hazard, especially Shawarma, as they may act as a potential vehicle for many antimicrobial-resistant pathogenic organisms. Improper hygienic standards and indiscriminate use of antimicrobials are two of the main causes for the prevalence of these pathogenic resistance strains in Lebanon. These results will emphasize the need to implement protective measures and more emphasis will be placed on the application of hygienic practices to reduce the levels of food contamination.
本研究的目的是在分子水平上对从黎巴嫩肉类快餐中分离出的不同沙门氏菌属和大肠杆菌菌株进行特征分析。此外，本研究评估了这些菌株对常用的不同抗菌药物的耐药性。所涉及的食品包括拉哈姆比阿金（LBA，肉馅饼）和沙瓦玛（类似旋转烤肉和多纳圈的黎巴嫩肉三明治，包含肉类、蔬菜和芝麻酱）。采用聚合酶链反应（PCR）对两种细菌的菌株进行特征分析和鉴定。沙门氏菌属的特征分析使用rfb基因簇遗传标记，而大肠杆菌菌株的特征分析则基于stx1、stx2、eaeA、fliC和ehlyA毒力标记。然后对特征明确的菌株进行各种抗菌药物反应测试。结果表明，所测试的食品被副伤寒沙门氏菌（血清群A）和产志贺毒素大肠杆菌（STX-EC）污染。PCR结果显示，在使用stx1引物进行的PCR中，75%的测试大肠杆菌菌株呈阳性，其中一株eaeA呈阳性。使用fliC引物进行PCR时，有两株测试菌株呈阳性。使用以下抗菌药物评估各种菌株的耐药性：苯唑西林、替考拉宁、甲氧苄啶/磺胺甲恶唑、庆大霉素、克林霉素、头孢噻肟、头孢呋辛、红霉素和万古霉素。细菌对一种或多种测试抗菌药物具有高度耐药性。约69%的大肠杆菌和77.8%的沙门氏菌属表现出耐药性。沙门氏菌属对四种抗菌药物呈现100%耐药：苯唑西林、替考拉宁、克林霉素、万古霉素和红霉素，而大肠杆菌对替考拉宁和甲氧苄啶/磺胺甲恶唑呈现100%耐药。最有趣的发现是大肠杆菌对庆大霉素的高敏感性（100%）。沙门氏菌属对头孢噻肟的耐药性最高（74%）。这两种抗菌药物常用于治疗由革兰氏阴性菌引起的肠道感染。结果表明，黎巴嫩的肉类快餐可能对公众健康构成危害，尤其是沙瓦玛，因为它们可能成为许多耐抗菌药物病原体的潜在传播媒介。卫生标准不当和抗菌药物的滥用是黎巴嫩这些耐药病原体菌株流行的两个主要原因。这些结果将强调实施保护措施的必要性，并将更加重视应用卫生措施以降低食品污染水平。
