College of Life Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China; Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051, People's Republic of China.
J Food Prot. 2013 Dec;76(12):2063-8. doi: 10.4315/0362-028X.JFP-13-161.
Vibrio vulnificus is a gram-negative bacterium that occurs naturally in estuarine and marine water and is associated with wound infections or septicemia related to the consumption of raw shellfish in humans. The molecular characteristics and antibiotic susceptibilities of V. vulnificus strains in shrimps from retail markets in Hangzhou, People's Republic of China, were investigated in this study. Thirty-three samples were positive for V. vulnificus in 78 shrimp samples which were collected from 15 retail markets between July and August 2012; the most-probable-number values ranged from 3 to 1,600 g(-1) in these positive samples, with a median most-probable-number value of 72 g(-1). Twenty-five biotype 1 strains and eight biotype 2 strains were identified by biochemical tests, and all strains could be definitively genotyped. By 16S rRNA genotyping, 21.2% (7 of 33) were classified as genotype A, 63.6% (21 of 33) as genotype B, and 15.2% (5 of 33) as genotype AB, while by virulence-correlated gene (vcg) typing, 21.2% (7 of 33) were characterized as genotype E and 78.8% (26 of 33) were genotype C. More than 50% of those isolates were identified as the potentially virulent type vcg type C-16S rRNA B (CB). The antibiotic susceptibilities of the V. vulnificus strains to 21 antimicrobial agents were tested as well. Some strains showed resistance or intermediate resistance to cefepime (3.03%), tetracycline (6.06%), aztreonam (24.24%), streptomycin (45.45%), gentamicin (93.94%), tobramycin (100%), and cefazolin (100%). Multiple-locus variable-number tandem repeat-based fingerprinting analysis (MLVA) was successfully applied to these 33 isolates and yielded 30 patterns that clustered into two MLVA groups; with a calculated Simpson's index of diversity of 0.994, this revealed that MLVA had great discriminating power for V. vulnificus. To minimize the potential risk of V. vulnificus infections due to the consumption of raw shrimp, it is necessary to monitor the hygiene status of seafood.
创伤弧菌是一种革兰氏阴性细菌，自然存在于港湾和海洋水中，与人类食用生贝类相关的伤口感染或败血症有关。本研究调查了中国杭州市零售市场虾中创伤弧菌菌株的分子特征和抗生素敏感性。2012 年 7 月至 8 月，从 15 个零售市场采集的 78 个虾样本中，有 33 个样本为创伤弧菌阳性，这些阳性样本的最可能数范围为 3 至 1600 g(-1)，中位数最可能数为 72 g(-1)。通过生化试验鉴定了 25 株生物型 1 株和 8 株生物型 2 株，所有菌株均可明确基因分型。通过 16S rRNA 基因分型，21.2%（33 株中的 7 株）被分类为基因型 A，63.6%（33 株中的 21 株）为基因型 B，15.2%（33 株中的 5 株）为基因型 AB，而通过毒力相关基因（vcg）分型，21.2%（33 株中的 7 株）为基因型 E，78.8%（33 株中的 26 株）为基因型 C。超过 50%的分离株被鉴定为潜在毒力型 vcg 型 C-16S rRNA B（CB）。还测试了创伤弧菌菌株对 21 种抗菌药物的抗生素敏感性。一些菌株对头孢吡肟（3.03%）、四环素（6.06%）、氨曲南（24.24%）、链霉素（45.45%）、庆大霉素（93.94%）、妥布霉素（100%）和头孢唑啉（100%）表现出耐药或中介耐药。多位点可变数串联重复基因指纹分析（MLVA）成功应用于这 33 株分离株，产生了 30 种模式，聚类为两个 MLVA 组；Simpson 多样性指数计算值为 0.994，表明 MLVA 对创伤弧菌具有很强的区分能力。为了最大限度地降低因食用生虾而感染创伤弧菌的潜在风险，有必要监测海产品的卫生状况。
