Submitted to: International Association for Food Protection
Publication Type: Abstract Only
Publication Acceptance Date: 4/2/2002
Publication Date: 5/30/2002
Citation: Feder, I.E., Gray, J.T., Pearce, R., Bush, E., Fratamico, P.M., Wallace, F.M., Cray, P.J., Perrine, R., Dudley, R.L., Luchansky, J.B. 2002. National animal health monitoring system swine 2000: a surveillance study of escherichia coli 0157 in swine. International Association for Food Protection. P. 87. P120.
Technical Abstract: As part of a national surveillance system (National Animal Health Monitoring System Swine 2000) to monitor the presence of pathogens in swine, 2526 swine fecal samples were collected from 57 sites in the top 17 swine producing states to investigate the natural occurrence of Escherichia coli 0157 in healthy swine. Ten grams of feces were placed into brilliant green bile broth for a six-hour enrichment and incubated at 37oC. One ml aliquots were removed and added to a suspension of E. coli 0157 antibody coated immunomagnetic beads. Beads processed by immunomagnetic separation were plated onto sorbitol MacConkey (SMAC) agar and cefixime/tellurite SMAC agar. Non-sorbitol fermenting colonies were tested for the presence of beta-glucuronidase and the ability ferment lactose using Escherichia coli broth containing 4-methylumbelliferyl-beta- D-glucuronide (MUG) and MacConkey broth, respectively. Lactose positive and MUG negative colonies were tested for 0157 latex agglutination. The 0157 latex agglutination positive isolates were tested for the presence genes encoding for the 0157 somatic antigen, Shiga toxins 1 and 2, intimin protein, hemolysin, and the H7 flagellum by PCR analysis. Of the 2526 samples tested, 102 E. coli 0157 isolates were recovered and were positive by PCR for the 0157 gene. Of these isolates, none were positive for the H7 flagellum or any of the virulence factors by PCR. The E. coli 0157 genotype was found in the feces of healthy swine. However, none of the isolates obtained in this study contained the virulence pattern associated with pathogenic E. coli 0157:H7.