Submitted to: Feedinfo News Service
Publication Type: Other
Publication Acceptance Date: 8/2/2004
Publication Date: 8/2/2004
Citation: Dean-Nystrom, E.A. 2004. Neonatal piglets as EHEC infection models. Feedinfo News Service. Available: http://www.feedinfo.com/guest/feedinfo/strategy.aspx.
Technical Abstract: Enterohemorrhagic Escherichia coli (EHEC) O157:H7 (hereafter called 'O157') and other Shiga toxin-producing E. coli (STEC) are a major cause of bloody diarrhea (hemorrhagic colitis) in humans. Up to 10% of patients with hemorrhagic colitis due to O157 develop the hemolytic uremic syndrome (HUS), a life-threatening complication of O157 infection that is a primary cause of acute kidney failure in children in North America. The most frequently reported serotype associated with human STEC disease in North America, the United Kingdom, and Japan is O157:H7, but other pathogenic STEC serotypes (non-O157:H7 STEC) are emerging, predominantly in Europe, Australia, and South America. Cattle are important sources of STEC strains that cause disease in humans. Our long-term goal is to prevent cattle from becoming infected and transmitting O157 and other STEC to humans. Although pigs are not recognized as important sources of STEC strains associated with human outbreaks, O157 strains have been identified in swine feces and pigs are susceptible to natural STEC disease (edema disease) and experimental STEC infections. Neonatal (< 1-d-old) piglets develop neurological signs, and sometimes diarrhea, at 2 to 7 days after they are orally inoculated with O157 or non-O157 STEC strains. Experimentally-inoculated piglets are colonized by STEC bacteria (i.e., have large numbers of O157 bacteria in their intestines and feces) and have histologic lesions in their intestines, brains, and kidneys. STEC infection studies in neonatal piglets have been instrumental in the identification of factors involved in STEC colonization and STEC-mediated disease. Information from these studies provides the basis for the development of intervention strategies that reduce infections in cattle and humans and therapeutic strategies that reduce the occurrence of life-threatening STEC complications in humans.