COMPARISON OF THE PATHOTYPES AND VIROTYPES OF PATHOGENIC ESCHERICHIA COLI IN DISEASED PIGS IN VIETNAM AND QUEBEC, CANADA Thuy, N. Do 1 ; Darren J. Trott 2 , Éric Nadeau 3 , Clarisse Desautels 4 , and John M. Fairbrother 4 1 National Institute of Veterinary Research, Viet Nam, 2 The University of Adelaide, SA 5055, Australia 3 Prevtec microbia Inc, Saint-Hyacinthe, Quebec, Canada 4 Reference laboratory for E. coli, Faculté de médecine vétérinaire, Université de Montréal, Canada . Introduction Diseases caused by E. coli have been a recognised problem for as long as pigs have been raised. Different categories of E. coli have been associated with diarrhoeal disease in animals worldwide with enterotoxigenic E. coli (ETEC) and Shiga toxin-producing E. coli (STEC) being the most common (DebRoy & Maddox, 2001). The objective of this study was to compare the distribution of virotypes of pathogenic E. coli isolates from diseased pigs in two geographically distinct countries, Vietnam and Canada. Materials and Methods E. coli isolates obtained from diseased pigs (diarrhea, sudden death or edema disease) in 2007 and submitted to the NIVR in Vietnam or the FMV in Québec, Canada, were initially tested by PCR for the presence of defining genes of ETEC and STEC pathotypes. They were then virotyped by colony hybridisation (Ngeleka et al., 2002) for detection of the presence of 20 virulence genes most commonly found in animal pathogenic E. coli. Results Table 1: Virotypes of ETEC-STEC isolates ETEC-STEC pathotype Number of isolates Virotype Vietnam Québec ETEC-STEC F18 LT:STa:Stx2:Paa:F18 13 0 STa:STb:Stx2:AIDA:F18 4 0 STa:STb:Stx2:Paa:AIDA:F18 3 0 Other 6 0 Total ETEC-STEC F18 26 0 Other 1 4 Table 2: Virotypes of STEC isolates STEC pathotype Number of isolates Virotype Vietnam Québec STEC F18 Stx2:Paa:AIDA:F18 4 2 Stx2:AIDA:F18 4 1 Stx2:EAST1:AIDA:F18 0 8 Other 2 3 Total STEC F18 10 14 Other 4 9 Table 3: Virotype of ETEC isolates ETEC pathotype Number of strains Virotype Vietnam Québec ETEC F4 LT:STa:STb:EAST1:Paa:F4 12 5 STa:STb:EAST1:F4 8 0 LT:STb:EAST1:F4 3 14 LT:STb:EAST1:Paa:F4 2 19 Other 2 8 Total ETEC F4 27 46 ETEC F18 STa:STb:AIDA:F18 3 0 LT:STa:STb:EAST1: F18 0 2 Other 3 1 Total ETEC F18 6 3 ETEC F5-F41 STa:Paa:F5 17 9 Other 0 4 Total ETEC F5-F41 17 13 Other LT:STa:STb:EAST1: Paa 7 0 Other 13 63 Total 20 63 Discussion Our results demonstrate that the most important pathotypes associated with diarrhea, ETEC F4, ETEC F18, and ETEC F5, and edema disease, STEC F18, are present in both countries. On the other hand, typing using additional virulence genes permitted further discrimination of the isolates, which demonstrated that distinct virotypes predominate in each country. Interestingly, the ETEC-STEC F18 pathotype, was very frequently observed in Vietnam, but was not identified in isolates from Quebec. Thus, virotyping is a valuable tool for monitoring the geographical distribution of virotypes worldwide and the emergence of new pathogenic variants. We are presently setting up a database for the global surveillance of animal pathogenic E. coli. References DebRoy, C. & Maddox, C. W. (2001). Animal Health Research Reviews 2, 129-140. Ngeleka M, Brereton L, Brown G, Fairbrother JM. 2002. Avian Dis 46:143-152. COMPARISON OF THE ANTIMICROBIAL RESISTANCE OF PATHOGENIC ESCHERICHIA COLI IN DISEASED PIGS IN VIETNAM AND QUEBEC, CANADA Thuy, N. Do 1 ; Darren J. Trott 2 , Éric Nadeau 3 , Clarisse Desautels 4 , and John M. Fairbrother 4 1 National Institute of Veterinary Research, Viet Nam, 2 The University of Adelaide, SA 5055, Australia 3 Prevtec microbia Inc, Saint-Hyacinthe, Quebec, Canada 4 Reference laboratory for E. coli, Faculté de médecine vétérinaire, Université de Montréal, Canada . Introduction Escherichia coli is an important cause of a wide range of diseases in production animals and humans worldwide, including pigs. In certain cases, animals are a reservoir of infection for humans, either by direct contact, contamination of the environment, or via contaminated food. The objective of this study was to compare the distribution of antimicrobial resistance of pathogenic E. coli isolates from diseased pigs in two geographically distinct countries, Vietnam and Canada, with differing antimicrobial use. Materials and Methods E. coli isolates obtained from diseased pigs (diarrhea, sudden death or edema disease) in 2007 and submitted to the NIVR in Vietnam or the FMV in Québec, Canada, were initially tested by PCR for the presence of defining genes of ETEC and STEC pathotypes. They were then virotyped by colony hybridisation (Ngeleka et al., 2002) for detection of the presence of 20 virulence genes most commonly found in animal pathogenic E. coli. The isolates were examined by the disk diffusion test to identify antimicrobial resistance. Results Table 1: Prevalence of antimicrobial resistance in pathogenic E. coli isolates % of resistance Antimicrobial Canada (n=124) Vietnam (n=50) Ceftiofur 5 0 Ampicillin 67 42 Apramycin 12 0 Spectinomycin 46 4 Gentamycin 7 14 Enrofloxacin 0 20 Florfenicol 12 32 Trim-Sulfa 48 82 Neomycin 23 18 Tetracycline 95 92 Figure 1: Prevalence of antimicrobial resistance in porcine pathogenic E. coli isolates from Vietnam and Canada Discussion The antimicrobial resistance profiles generated can be considered to be representative of each geographical region. Some interesting similarities and differences were demonstrated between the two data sets. Overall, very high rates of resistance were found to tetracycline in isolates from both countries, Canada and Vietnam (95 and 92%, respectively). Interestingly, all the Vietnamese isolates were sensitive to ceftiofur and apramycin, whereas no resistance was recorded for enrofloxacin with the Canadian isolates. The similarities and differences in antimicrobial resistance between the two countries could be attributed to variation in veterinary antimicrobial regulation and usage between Canada and Vietnam. This was definitely the case for tetracycline, ampicillin, and sulfa drug use in both countries, and ceftiofur and apramycin use in Canada, and enrofloxacin use in Vietnam. Frequent usage of agents in the past, such as chloramphenicol in Vietnam and nitrofurantoin in Canada also was associated with resistance. Other factors may include the distribution of serotypes and pathotypes between the two countries, and differences in farrowing shed management. References Ngeleka M, Brereton L, Brown G, Fairbrother JM. 2002. Avian Dis 46:143-152. 0 10 20 30 40 50 60 70 80 90 100 Ceftiofu r Ampicil li n A pr amycin Gentamycin Neomycin Enrofloxacin Florfenicol S p ectinomycin Tr i m‐Sulfa Tetracy cline C anada Vietnam . in both countries, and ceftiofur and apramycin use in Canada, and enrofloxacin use in Vietnam. Frequent usage of agents in the past, such as chloramphenicol in Vietnam and nitrofurantoin in. COMPARISON OF THE PATHOTYPES AND VIROTYPES OF PATHOGENIC ESCHERICHIA COLI IN DISEASED PIGS IN VIETNAM AND QUEBEC, CANADA Thuy, N. Do 1 ; Darren J. Trott 2 ,. Fairbrother JM. 2002. Avian Dis 46:143-152. COMPARISON OF THE ANTIMICROBIAL RESISTANCE OF PATHOGENIC ESCHERICHIA COLI IN DISEASED PIGS IN VIETNAM AND QUEBEC, CANADA Thuy, N. Do 1 ; Darren J. Trott 2 ,