Phenotypic and Genotypic characterization of hypervirulent strains of Clostridium difficile of human and porcine origin

                        pigs


Clostridium difficile, particularly the hypervirulent strains, have been shown to be of importance to swine and human medicine.  Hypervirulent strains have caused multi-state outbreaks in humans in recent years (McDonald et al., 2005.). Though this organism has been identified commonly in piglets, its zoonotic significance and food safety significance has not been elucidated.  The main objectives of this project are:

  • To determine whether piglets infected with C. difficile remain carriers at nursery to finishing and can potentially serve as a source of the organism to other pigs in the farm to processing continuum
  • To assess the food safety significance of C. difficile and conduct phenotypic and genotypic analyses of C. difficile isolates using toxinotyping (PCR-RFLP) and DNA fingerprinting (primarily PFGE).
  • Conduct detailed molecular characterization of the regulator gene, tcdC to determine the likelihood of strains of porcine origin to cause CDAD in humans.  
                         C. difficilegene tcdC
The findings in the proposed project could result in identification of a new risk factor and transmission route for C. difficile. It will also contribute to better understanding of Clostridium difficile associated disease (CDAD) and will be beneficial to both pork consumers, by increasing food safety, as well as pork producers, by reducing piglet diarrhea often known to be caused by this organism.

IDMEL Personnel:

Pamela Fry (Master's Student)
Wondwossen A. Gebreyes (Principle Investigator)

Other Collaborators:

Siddhartha Thakur (North Carolina State University)
Keith Kaye (Duke University)
Christopher Woods  (Duke University)

Source of Funding:

National Pork Board