Isolation and characterization of non-O157 Shiga toxin-producing <i>Escherichia coli</i> from beef carcasses, cuts and trimmings of abattoirs in Argentina

Several foods contaminated with Shiga toxin-producing Escherichia coli (STEC) are associated with human diseases. Some countries have established microbiological criteria for non-O157 STEC, thus, the absence of serogroups O26, O45, O103, O104, O111, O121, and O145 in sprouts from the European Union or ground beef and beef trimmings from the United States is mandatory. While in Argentina screening for O26, O103, O111, O145 and O121 in ground beef, ready-to-eat food, sausages and vegetables is mandatory, other countries have zero-tolerance for all STEC in chilled beef. The aim of this study was to provide data on the prevalence of non-O157 STEC isolated from beef processed in eight Argentinean cattle slaughterhouses producing beef for export and local markets, and to know the non-O157 STEC profiles through strain characterization and genotypic analysis. Samples (n = 15,965) from 3,205 beef carcasses, 9,570 cuts and 3,190 trimmings collected between March and September 2014 were processed in pools of five samples each. Pools of samples (n = 3,193) from 641 carcasses, 1,914 cuts and 638 trimming were analyzed for non-O157 STEC isolation according to ISO/CEN 13136:2012. Of these, 37 pools of carcasses (5.8%), 111 pools of cuts (5.8%) and 45 pools of trimmings (7.0%) were positive for non-O157 STEC. STEC strains (n = 200) were isolated from 193 pools of samples. The most prevalent serotypes were O174:H21, O185:H7, O8:H19, O178:H19 and O130:H11, and the most prevalent genotypes were stx2c(vh-b) and stx2a/saa/ehxA. O103:H21 strain was eae-positive and one O178:H19 strain was aggR/aaiC-positive. The prevalence of non-O157 STEC in beef carcasses reported here was low. None of the non-O157 STEC strains isolated corresponded to the non-O157 STEC serotypes and virulence profiles isolated from human cases in Argentina in the same study period. The application of microbiological criteria for each foodstuff should be determined by risk analysis in order to have a stringent monitoring system. Likewise, zero-tolerance intervention measures should be applied in beef, together with GMP and HACCP. Further, collaborative efforts for risk assessment, management and communication are extremely important to improve the safety of foodstuffs.Instituto de Genética VeterinariaFacultad de Ciencias Veterinaria

Isolation and characterization of non-O157 Shiga toxin-producing <i>Escherichia coli</i> from beef carcasses, cuts and trimmings of abattoirs in Argentina

Several foods contaminated with Shiga toxin-producing Escherichia coli (STEC) are associated with human diseases. Some countries have established microbiological criteria for non-O157 STEC, thus, the absence of serogroups O26, O45, O103, O104, O111, O121, and O145 in sprouts from the European Union or ground beef and beef trimmings from the United States is mandatory. While in Argentina screening for O26, O103, O111, O145 and O121 in ground beef, ready-to-eat food, sausages and vegetables is mandatory, other countries have zero-tolerance for all STEC in chilled beef. The aim of this study was to provide data on the prevalence of non-O157 STEC isolated from beef processed in eight Argentinean cattle slaughterhouses producing beef for export and local markets, and to know the non-O157 STEC profiles through strain characterization and genotypic analysis. Samples (n = 15,965) from 3,205 beef carcasses, 9,570 cuts and 3,190 trimmings collected between March and September 2014 were processed in pools of five samples each. Pools of samples (n = 3,193) from 641 carcasses, 1,914 cuts and 638 trimming were analyzed for non-O157 STEC isolation according to ISO/CEN 13136:2012. Of these, 37 pools of carcasses (5.8%), 111 pools of cuts (5.8%) and 45 pools of trimmings (7.0%) were positive for non-O157 STEC. STEC strains (n = 200) were isolated from 193 pools of samples. The most prevalent serotypes were O174:H21, O185:H7, O8:H19, O178:H19 and O130:H11, and the most prevalent genotypes were stx2c(vh-b) and stx2a/saa/ehxA. O103:H21 strain was eae-positive and one O178:H19 strain was aggR/aaiC-positive. The prevalence of non-O157 STEC in beef carcasses reported here was low. None of the non-O157 STEC strains isolated corresponded to the non-O157 STEC serotypes and virulence profiles isolated from human cases in Argentina in the same study period. The application of microbiological criteria for each foodstuff should be determined by risk analysis in order to have a stringent monitoring system. Likewise, zero-tolerance intervention measures should be applied in beef, together with GMP and HACCP. Further, collaborative efforts for risk assessment, management and communication are extremely important to improve the safety of foodstuffs.Instituto de Genética VeterinariaFacultad de Ciencias Veterinaria

Isolation and characterization of non-O157 Shiga toxin-producing <i>Escherichia coli</i> from beef carcasses, cuts and trimmings of abattoirs in Argentina

Several foods contaminated with Shiga toxin-producing Escherichia coli (STEC) are associated with human diseases. Some countries have established microbiological criteria for non-O157 STEC, thus, the absence of serogroups O26, O45, O103, O104, O111, O121, and O145 in sprouts from the European Union or ground beef and beef trimmings from the United States is mandatory. While in Argentina screening for O26, O103, O111, O145 and O121 in ground beef, ready-to-eat food, sausages and vegetables is mandatory, other countries have zero-tolerance for all STEC in chilled beef. The aim of this study was to provide data on the prevalence of non-O157 STEC isolated from beef processed in eight Argentinean cattle slaughterhouses producing beef for export and local markets, and to know the non-O157 STEC profiles through strain characterization and genotypic analysis. Samples (n = 15,965) from 3,205 beef carcasses, 9,570 cuts and 3,190 trimmings collected between March and September 2014 were processed in pools of five samples each. Pools of samples (n = 3,193) from 641 carcasses, 1,914 cuts and 638 trimming were analyzed for non-O157 STEC isolation according to ISO/CEN 13136:2012. Of these, 37 pools of carcasses (5.8%), 111 pools of cuts (5.8%) and 45 pools of trimmings (7.0%) were positive for non-O157 STEC. STEC strains (n = 200) were isolated from 193 pools of samples. The most prevalent serotypes were O174:H21, O185:H7, O8:H19, O178:H19 and O130:H11, and the most prevalent genotypes were stx2c(vh-b) and stx2a/saa/ehxA. O103:H21 strain was eae-positive and one O178:H19 strain was aggR/aaiC-positive. The prevalence of non-O157 STEC in beef carcasses reported here was low. None of the non-O157 STEC strains isolated corresponded to the non-O157 STEC serotypes and virulence profiles isolated from human cases in Argentina in the same study period. The application of microbiological criteria for each foodstuff should be determined by risk analysis in order to have a stringent monitoring system. Likewise, zero-tolerance intervention measures should be applied in beef, together with GMP and HACCP. Further, collaborative efforts for risk assessment, management and communication are extremely important to improve the safety of foodstuffs.Instituto de Genética VeterinariaFacultad de Ciencias Veterinaria

La intervención motivacional y sus efectos sobre la entrada a tratamiento de adicción

Se presentan los resultados de un estudio de caso acerca de las vivencias de sujetos que participaron en un proceso de intervención motivacional (IM) de seis semanas de duración, que incluye la participación de terceros significativos. Se discute la importancia de incluir la llamada muestra de abstinencia en una intervención que busque motivar a la entrada a un tratamiento de adicción. Los sujetos participantes son seis adultos, con edades entre 25 y 45 años, de sexo masculino, que habían participado de un modo de intervención específico llamado intervención motivacional, que incluye la muestra de abstinencia. A partir de un análisis cualitativo de los datos, se describen los cambios producidos durante este proceso y la forma en que estos cambios facilitan que los sujetos tomen la decisión de tratarse. Los resultados muestran que la muestra de abstinencia, realizada en el contexto de una intervención con las características de la IM, tienen un efecto positivo en la decisión de los sujetos de entrar a un tratamiento. Finalmente, se remarca la importancia de ofrecer un modo de intervención que lleve a que el sujeto se sienta parte activa del proceso de cambio

La intervención motivacional y sus efectos sobre la entrada a tratamiento de adicción

The results of a case study regarding the experiences of individuals who participated in a motivational intervention (MI) process for a six week period which includes the participation of significant others are presented. The importance of including the so called sobriety sampling in an intervention that looks for motivating the entrance to an addiction treatment is discussed. The individuals who participated are six male adults aged between 25 and 45, who had already participated on a specific mode of intervention called motivational intervention (MI), which includes the sobriety sampling. The changes produced during this process are described based on qualitative analysis of the data. Results show that the sobriety sampling, in the context of an intervention with the characteristics of the MI, makes it easier for individuals to take the decision to treat themselves. Finally, the importance of offering a mode of intervention in which the subject is an active part of the process of change is highlighted.Se presentan los resultados de un estudio de caso acerca de las vivencias de sujetos que participaron en un proceso de intervención motivacional (IM) de seis semanas de duración, que incluye la participación de terceros significativos. Se discute la importancia deincluir la llamada muestra de abstinencia en una intervención que busque motivar a la entrada a un tratamiento de adicción. Los sujetos participantes son seis adultos, con edades entre 25 y 45 años, de sexo masculino, que habían participado de un modo de intervención específico llamado intervención motivacional, que incluye la muestra de abstinencia. A partir de un análisis cualitativo de los datos, se describen los cambios producidos durante este proceso y la forma en que estos cambios facilitan que los sujetos tomen la decisión de tratarse. Los resultados muestran que la muestra de abstinencia, realizada en el contexto de una intervención con las características de la IM, tienen un efecto positivo en la decisión de los sujetos de entrar a un tratamiento. Finalmente, se remarca la importancia de ofrecer un modo de intervención que lleve a que el sujeto se sienta parte activa del proceso de cambio

Evaluation of decontamination efficacy of commonly used antimicrobial interventions for beef carcasses against Shiga toxin-producing Escherichia coli

In Argentina, Shiga toxin producing Escherichia coli (STEC) serogroups O157, O26, O103, O111, O145 and O121 are adulterant in ground beef. In other countries, the zero-tolerance approach to all STEC is implemented for chilled beef. Argentinean abattoirs are interested in implementing effective interventions against STEC on carcasses. Pre-rigor beef carcasses were used to determine whether nine antimicrobial strategies effectively reduced aerobic plate, coliform and E. coli counts and stx and eae gene prevalence. These strategies were: citric acid (2%; automated), acetic acid (2%; manual and automated), lactic acid (LA 2%; manual and automated), LA (3%; automated), electrolytically-generated hypochlorous acid (400 ppm; manual), hot water (82 °C; automated) and INSPEXX (0.2%; automated). Automated application of 2% LA after 30–60-min aeration and 3% LA at 55 °C were the most effective interventions. Automated application was more effective than manual application. Decontamination of beef carcasses through automated application of lactic acid and hot water would reduce public health risks associated with STEC contamination.Fil: Signorini Porchietto, Marcelo Lisandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Costa, Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Teitelbaum, David. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Restovich, Viviana. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Brasesco, Hebe. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: García, Diego. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Superno, Valeria. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Petroli, Sandra. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Bruzzone, Mariana. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Arduini, Victor. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Vanzini, Mónica. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Sucari, Adriana. Centro Estudios Infectológicos “Dr. Daniel Stamboulian”; ArgentinaFil: Suberbie, Germán. Ministerio de Agricultura, Ganadería, Pesca y Alimento. Servicio Nacional de Sanidad y Calidad Agroalimentaria; ArgentinaFil: Maricel, Turina. Instituto de Promoción de la Carne Vacuna Argentina; ArgentinaFil: Rodríguez, Ricardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; ArgentinaFil: Leotta, Gerardo Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentin

A rapid and simple protocol for concentration of SARS-CoV-2 from sewage

The aim of this study was to set up a simple protocol to concentrate SARS-CoV-2 from sewage, which can be implemented in laboratories with minimal equipment resources. The method avoids the need for extensive purification steps and reduces the concentration of potential inhibitors of RT-qPCR contained in sewage. The concentration method consists of a single step, in which a small volume (40 mL) of sewage sample is incubated with polyaluminum chloride (PAC)(0.00045 N Al3+ final concentration). Virus particles adsorbed to the precipitate are collected by low-speed centrifugation, after which the recovered pellet is resuspended with a saline buffer. PAC-concentrated samples are stable for at least one week at 4 °C. Therefore, they may be sent refrigerated to a diagnosis center for RNA extraction and RT-qPCR for SARS-CoV-2 RNA detection if the lab does not have such capabilities. The PAC concentration method produced an average shift of 4.5-units in quantification cycle (Cq) values compared to non-concentrated samples, indicating a 25-fold increase in detection sensitivity. The lower detection limit corresponded approximately to 100 viral copies per ml. Kappa index indicated substantial agreement between PAC and polyethylene glycol (PEG) precipitation protocols (k = 0.688, CI 0.457−0.919). This low-cost concentration protocol could be useful to aid in the monitoring of community circulation of SARS-CoV-2, especially in low- and middle-income countries, which do not have massive access to support from specialized labs for sewage surveillance.Fil: Wehrendt, Diana Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Mariana, Massó. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Gonzales Machuca, Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Vargas, Claudia Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Unidad Ejecutora de Investigaciones en Producción Animal. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Unidad Ejecutora de Investigaciones en Producción Animal; ArgentinaFil: Barrios, Melina Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Campos, Josefina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: Costamagna, Damián. Autoridad del Agua. - Gobierno de la Provincia de Buenos Aires. Ministerio de Infraestructura y Servicos Publicos. Autoridad del Agua.; ArgentinaFil: Bruzzone, Luis. Aguas Bonaerenses S.A; ArgentinaFil: Cisterna, Daniel Marcelo. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: Iglesias, Nestor Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; ArgentinaFil: Mbayed, Viviana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y BioquÍmica. Instituto de Investigaciones En Bacteriología y Virología Molecular (IBaViM); Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Baumeister, Elsa. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: Centron, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Quiroga, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Erijman, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular; Argentin

Isolation and characterization of non-O157 Shiga toxin-producing Escherichia coli from beef carcasses, cuts and trimmings of abattoirs in Argentina.

Several foods contaminated with Shiga toxin-producing Escherichia coli (STEC) are associated with human diseases. Some countries have established microbiological criteria for non-O157 STEC, thus, the absence of serogroups O26, O45, O103, O104, O111, O121, and O145 in sprouts from the European Union or ground beef and beef trimmings from the United States is mandatory. While in Argentina screening for O26, O103, O111, O145 and O121 in ground beef, ready-to-eat food, sausages and vegetables is mandatory, other countries have zero-tolerance for all STEC in chilled beef. The aim of this study was to provide data on the prevalence of non-O157 STEC isolated from beef processed in eight Argentinean cattle slaughterhouses producing beef for export and local markets, and to know the non-O157 STEC profiles through strain characterization and genotypic analysis. Samples (n = 15,965) from 3,205 beef carcasses, 9,570 cuts and 3,190 trimmings collected between March and September 2014 were processed in pools of five samples each. Pools of samples (n = 3,193) from 641 carcasses, 1,914 cuts and 638 trimming were analyzed for non-O157 STEC isolation according to ISO/CEN 13136:2012. Of these, 37 pools of carcasses (5.8%), 111 pools of cuts (5.8%) and 45 pools of trimmings (7.0%) were positive for non-O157 STEC. STEC strains (n = 200) were isolated from 193 pools of samples. The most prevalent serotypes were O174:H21, O185:H7, O8:H19, O178:H19 and O130:H11, and the most prevalent genotypes were stx2c(vh-b) and stx2a/saa/ehxA. O103:H21 strain was eae-positive and one O178:H19 strain was aggR/aaiC-positive. The prevalence of non-O157 STEC in beef carcasses reported here was low. None of the non-O157 STEC strains isolated corresponded to the non-O157 STEC serotypes and virulence profiles isolated from human cases in Argentina in the same study period. The application of microbiological criteria for each foodstuff should be determined by risk analysis in order to have a stringent monitoring system. Likewise, zero-tolerance intervention measures should be applied in beef, together with GMP and HACCP. Further, collaborative efforts for risk assessment, management and communication are extremely important to improve the safety of foodstuffs