Del Grosso M, Caprioli A, Chinzari P, Fontana M C, Pezzotti G, Manfrin A, Giannatale E D, Goffredo E, Pantosti A
Laboratory of Bacteriology and Medical Mycology, Istituto Superiore di Sanità, Rome, Italy.
Microb Drug Resist. 2000 Winter;6(4):313-8. doi: 10.1089/mdr.2000.6.313.
The emergence of vancomycin-resistant enterococci (VRE) in Europe has been ascribed to the long-time use of the glycopeptide antibiotic avoparcin as feed additive in food animals, until its ban in 1997 in EU. The pres- ence of VRE in food of animal origin is believed to represent a potential risk for the consumer. We studied the fecal carriage of VRE in broiler chickens and slaughter pigs in Italy before the avoparcin ban and eval- uated the impact of avoparcin withdrawal on the presence of VRE in raw meat products. Broilers and pigs were both found to be frequently colonized by VRE, as 36% and 24.6% of the flocks or the herds, respec- tively, were positive. Molecular typing of VRE strains by PFGE showed that animals housed in different pens within the same farm were colonized by clonally related strains. After the avoparcin ban, a decrease in the rate of VRE contamination in meat products was observed. Such a decrease was statistically significant in poultry (from 18.8% to 9.6%) but not in pork products (from 9.7% to 6.9%). The majority of VRE from all sources carried the vanA resistance gene and included Enterococcus faecium, E. faecalis, E. hirae, E. durans, and E. gallinarum. None of the strains carried the vanB gene, whereas constitutively resistant vanC-positive strains were frequently found. Our results show that avoparcin withdrawal has been successful in reducing VRE contamination in meat products. However, this measure needs to be complemented by a prudent use of glycopeptide antibiotics in human medicine.
欧洲耐万古霉素肠球菌（VRE）的出现被归因于长期将糖肽类抗生素阿伏帕星作为饲料添加剂用于食用动物，直到1997年在欧盟被禁用。动物源性食品中存在VRE被认为对消费者构成潜在风险。我们研究了在意大利禁用阿伏帕星之前肉鸡和屠宰猪粪便中VRE的携带情况，并评估了停用阿伏帕星对生肉制品中VRE存在情况的影响。结果发现肉鸡和猪都经常被VRE定植，分别有36%的鸡群和24.6%的猪群呈阳性。通过脉冲场凝胶电泳（PFGE）对VRE菌株进行分子分型表明，同一农场内不同围栏饲养的动物被克隆相关菌株定植。禁用阿伏帕星后，观察到肉制品中VRE污染率有所下降。这种下降在禽类中具有统计学意义（从18.8%降至9.6%），但在猪肉制品中没有统计学意义（从9.7%降至6.9%）。所有来源的大多数VRE携带vanA耐药基因，包括屎肠球菌、粪肠球菌、海氏肠球菌、耐久肠球菌和鹑鸡肠球菌。没有菌株携带vanB基因，而经常发现组成型耐药的vanC阳性菌株。我们的结果表明，停用阿伏帕星成功降低了肉制品中VRE的污染。然而，这一措施需要辅之以在人类医学中谨慎使用糖肽类抗生素。
