Date Full Report Received07/22/2009
Date Abstract Report Received07/22/2009
Funded ByNational Pork Board
We investigated the role of pigs in carrying important strains of C. difficile and the main goal was to determine the prevalence and compare strains of human and porcine origin. Samples were collected from swine farms in Ohio and North Carolina at farrowing, nursery, and finishing stages. The organism was found in 74.5% of farrowing piglets, 0.45% within nursery pigs, and 0% within finishing pig. A low level of multi-drug resistance was found, although most samples were ciprofloxacin resistant. The majority of isolates were found to be toxigenic. While none of the pigs were found to carry the hypervirulent epidemic strain of human health significance (NAP-1), 82.5% (161/195) were found to carry C. difficile strains which are Toxinotype V, a strain previously known to cause disease in humans and isolated from various other animal sources. Pulsed Field Gel Electrophoresis (PFGE) DNA fingerprinting show a high level of diversity among isolates of swine origin, with clustering among farms. The results also show a subset of Toxinotype V strains of swine origin with 100% similarity to human isolate. While it is encouraging that C. difficile was not found at the finishing stage of production indicating the absence of food safety concern, the occurrence of hypervirulent strains in swine similar to those of human origin could be significant.