Swift Jacob M, Foster Derek M, Rogers Anna T, Sylvester Hannah J, Griffith Emily H, Jacob Megan E
1 Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University , Raleigh, North Carolina.
2 Department of Statistics, College of Sciences, North Carolina State University , Raleigh, North Carolina.
Foodborne Pathog Dis. 2017 Mar;14(3):160-166. doi: 10.1089/fpd.2016.2213. Epub 2017 Jan 11.
Small ruminants have been implicated in outbreaks of Escherichia coli O157:H7 at livestock exhibitions throughout the United States. Additionally, goat meat or milk may serve as a reservoir for foodborne transmission of the organism. These associations highlight the public health importance of an effective strategy to reduce E. coli O157:H7 shedding in goats. We examined the efficacy of the SRP vaccine in goats orally challenged with E. coli O157:H7. Mixed-breed goats (n = 14) were randomly allocated into vaccinated and unvaccinated treatments (n = 7 per treatment). Goats were housed with a vaccinated and unvaccinated animal in each pen. Feces were collected for 3 weeks, then at necropsy, gastrointestinal contents were collected to determine the concentration of E. coli O157:H7. Three isolates per positive sample were saved and evaluated by pulsed-field gel electrophoresis (PFGE) to assess strain persistence over time. The mean concentration of E. coli O157:H7 in the feces of goats was numerically reduced in the vaccinated treatment; however, it was not statistically significant. In addition, the total number of days goats were fecal positive for E. coli O157:H7 were not different between vaccinated and unvaccinated treatments. Pulsotypes of isolates revealed that goats initially shed two of the four challenge strains of E. coli O157:H7, after which there was a distinct shift to two different strains. Further work is needed to evaluate cost-effective intervention strategies that reliably reduce E. coli O157:H7 shedding in goats, particularly those that may reduce the risk of transmission at public events, including petting zoos and fairs.
在美国各地的牲畜展览会上，小型反刍动物被认为与大肠杆菌O157:H7疫情爆发有关。此外，山羊肉或羊奶可能是该生物体食源性传播的储存宿主。这些关联凸显了制定有效策略以减少山羊体内大肠杆菌O157:H7排泄量的公共卫生重要性。我们研究了SRP疫苗对经大肠杆菌O157:H7口服攻毒的山羊的有效性。将混种山羊（n = 14）随机分为接种疫苗组和未接种疫苗组（每组n = 7）。每只围栏中饲养一只接种疫苗的山羊和一只未接种疫苗的山羊。收集粪便3周，然后在尸检时收集胃肠道内容物，以确定大肠杆菌O157:H7的浓度。每个阳性样本保存3个分离株，并通过脉冲场凝胶电泳（PFGE）进行评估，以评估菌株随时间的持续性。接种疫苗组山羊粪便中大肠杆菌O157:H7的平均浓度在数值上有所降低；然而，差异无统计学意义。此外，接种疫苗组和未接种疫苗组山羊粪便中大肠杆菌O157:H7呈阳性的总天数没有差异。分离株的脉冲型显示，山羊最初排出了大肠杆菌O157:H7的四种攻毒株中的两种，之后明显转变为另外两种不同的菌株。需要进一步开展工作，以评估能可靠减少山羊体内大肠杆菌O157:H7排泄量的具有成本效益的干预策略，特别是那些可能降低在包括宠物动物园和集市在内的公共活动中传播风险的策略。
