Detection and characterization of Shiga toxin-producing Escherichia coli in pigs and pig carcasses in Argentina

COLELLO, ROCÍO; RUIZ, MARÍA JULIA; SANZ, MARCELO, E; ETCHEVERRÍA, ANALÍA I.; PADOLA, NORA L.

Boston

Simposio; 9 th Internacional Symposium on Shiga Toxin (Verocytotoxin) Producing Escherichia coli Infections (VTEC 2015).; 2015

VTEC 2105

Detection and characterization of Shiga toxin-producing Escherichia coli in pigs and pig carcasses in ArgentinaColello, R1; Ruiz M J1; Sanz M E1; Etcheverría A I1; Padola N L1.1Laboratorio de Inmunoquímica y Biotecnología, Centro de Investigación Veterinaria de Tandil (CIVETAN), CONICET, CICPBA, Facultad de Ciencias Veterinarias, UNCPBA, Pinto 399 (7000), Tandil, Argentina.Introduction: Shiga toxin-producing Escherichia coli (STEC) are an important cause of foodborne illnesses worldwide that can cause gastrointestinal disease in humans, particularly infections that result in life threatening complications such as hemolytic-uremic syndrome.This study reports the prevalence of STEC in pigs and pig carcasses and the characterization of the isolates.Methods: From May 2012 to November 2013 different samples were taken from two pig farms and two boning rooms from Argentina.Three hundred and eighty samples were collected, from which 275 corresponded to rectal swabs, 26 to samples of feed, 48 to fecal samples and 31 pig carcasses (each part of the carcasses was individually processed taking a total of 144 samples). They were characterized by multiplex PCR to detect vt1, vt2,vt2eeae, ehxA and saa and then were serotyped.Results and discussion: Of the total of samples, 2.86 % of rectal swabs and 22.58 % of carcasses were STEC positive. From positive samples, 40 isolates could be characterized, from rectal swabs 37.5% of the isolates carried stx1/stx2 genes, 37.5 % possessed stx2e and 25% carried stx2. In carcasses we detected samples positive for stx1/stx2 54.16%, stx2 25%, stx2e 12.5%,stx1 4.1%. One isolate from carcasses carried the eae gene combined with stx2 and stx2e and three combined with stx2. The 29 strains were typed into 13 Escherichia coli O groups (O1, O2, O8, O15, O20, O35, O69, O78, O91, O121, O142, O157 and O180) and 11 were considered O nontypable. Implications: Results of the present research highlight the presence of STEC and it is important because implies serious health risks to consumers. This highlights the urgent need for the authorities to assess and identify strategies to reduce microbiological hazards, and implement control measures at all stages of the food chain to specifically reduce the presence of STEC in pigs.