Detection of integrons class 1 and class 2 in VTEC strains isolated from pigs

Introduction and objectives: In the last 10 years, approximately 500 HUS new annual cases w ere reported in Argentina, w ith an incidence of 17/100,000 children under five years old. The production of VT1, VT2 and/or their variants is the primary virulence trait responsible for human disease. VT2e is typically associated w ith pig edema disease and has been detected only rarely in VTEC of human origin. Some studies have show n that VTEC serotypes have developed resistance to antibiotics used in human and veterinary medicine. Humans may obtain antibiotic-resistant E. coli by contact with animals, foods, or environment. The w idespread use of antibiotics creates a reservoir of resistant bacteria carrying antibiotic resistance genes. Integrons contain the genetic determinants of the components of a site-specific recombination system w hich recognize and capture the mobile antibiotic-resistance genes cassette. Integrons include a gene for an integrase (int), an adjacent recombination site (attl), and a strong promoter/s that ensure expression of the integrated cassettes.The aim of this study w as to detect integrons in VTEC strains with antibiotic multiresistance. Material & Methods: Tw enty-one VTEC strains isolated from pig faeces f rom ten farms (named A to J) f rom Argentina w ere analysed to detect integrons (int1 and int2) by PCR. Results: Out of tw enty-one analysed strains, 8 (38 %) carried integrons enconding genes. These strains belonged to 4 different farms. Conclusions: The use of antibiotics in animal production systems has determined that bacteria could develop resistance mechanisms originating strains w ith risk for human if entering a food chain. Integrons are not only associated w ith resistance to antibiotics, but also w ith the horizontal transference of resistance genes. Some studies have informed of the presence of integrons in Enterobacteriaceae and Escherichia coli in samples isolated f rom pigs, not being registered data in VTEC strains so far. In this study integrons class 1 and class 2 w ere detected in VTEC strains isolated from pigs show ing that inadequate use of antibiotic as therapeutic agents or grow ing promoter in veterinary, implies a risk for public health because the acquisition and the horizontal transference of integrons among strains. Fil: Colello, Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina Fil: Moredo, Fabiana Alicia. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina