RESUMO
Multiplex PCR for the detection of sea, seb, sec, sed and see genes of Staphylococcus aureus. Characterization of isolates from food. The presence of Staphylococcus aureus in food represents a potential risk to public health, being its enterotoxins the major virulence factor. Enterotoxin detection can be determined by ELISA, but only for the pool of enterotoxins SEA, SEB, SEC, SED and SEE. The main aims of this study were to optimize two PCR techniques for detection of S. aureus sea, seb, sec, sed and see, and to characterize Staphylococcus spp. isolates associated with food intoxication. Two PCR techniques were optimized and 115 Staphylococcus spp. isolates from Ciudad Aut6noma de Buenos Aires, and Buenos Aires, Córdoba, and Neuquén provinces were characterized. The characterization was performed by biochemical tests, ELISA and PCR. Sixty-eight isolates (59.1%) were positive by ELISA, while 61 (53%) were positive by PCR. Out of the positive PCR isolates, 34 (55.7%) carried the sea gene, 9 (14.8%) the seb gene, 5 (8.1%) the see gene, 4 (6.5%) the sec gene, 6 (9.9%) were positive for sea and seb genes, 2 (3.3%) for sea and sec genes, and 1 (1.7%) for sea and sedgenes. This is the first study of genotypic characterization of S. aureus isolates associated with food intoxication from different provinces of Argentina.
Assuntos
Genes Bacterianos/genética , Staphylococcus aureus/genética , Microbiologia de Alimentos , Reação em Cadeia da Polimerase/métodos , Staphylococcus aureus/isolamento & purificaçãoRESUMO
En febrero de 2006 ocurrió un brote epidémico de gastroenteritis aguda de origen alimentario, en ocasión de un festejo popular en una pequeña localidad de la provincia de Neuquén, Argentina. Aproximadamente 800 personas participaron de un almuerzo en las instalaciones del Gimnasio Municipal, y unas tres horas después de finalizado, cerca de 150 asistentes consultaron al hospital local, afectados por síndrome gastroentérico agudo. Se realizó una investigación epidemiológica caso-control a través de un muestreo representativo no probabilístico. Los resultados epidemiológicos establecieron un brote de ETA a fuente común, con una relación caso-control de 1:1,8. Los principales síntomas fueron cólicos abdominales (88%), vómitos (73,5%) y diarrea (60%). La torta que se sirvió en ese evento fue identificada como el alimento causal (OR 9,79; IC 95%; 2,66-36,00; valor p = 0,0001), sujeto a condiciones higiénico-sanitarias insatisfactorias en los diferentes procesos de elaboración, conservación y manipulación. De una porción de la torta se aisló una cepa de Staphylococcus aureus subespecie aureus, coagulasa positiva, enterotoxigénica, con un recuento de 2,4x10(6) UFC/g, y también se aisló este microorganismo de tres muestras de manos y narinas de personas involucradas en la preparación y el servicio. Las cepas aisladas de un operador y de la torta portaron el gen sea y presentaron el mismo patrón de SmaI-PFGE. Se atribuyó el brote de ETA a la contaminación durante el proceso de preparación de la torta consumida durante ese almuerzo popular, lo que podría estar relacionado con deficiencias en aspectos higiénicos y con la falta de refrigeración y de mantenimiento de la cadena de frío.
In the summer of 2006, an epidemic outbreak of acute gastrointestinal illness related to food consumption occurred in a small town in the province of Neuquén, Argentina. During a popular feast, approximately 800 local residents attended lunch held in the facilities of the Municipal Gymnasium. About three hours later, nearly 150 attendees sought medical assistance at the local hospital due to acute gastroenteritis. A case-control epidemiological investigation was conducted using representative non-probability sampling. The epidemiological investigation showed a common-source foodborne disease outbreak with a case-control ratio of 1:1.8. The main symptoms were abdominal cramps (88%), vomiting (73.5%) and diarrhea (60%). The cake was identified as the source of infection (OR 9.79; IC 95%, 2.66-36.00; p = 0.0001), and unsatisfactory hygienic conditions in food production, conservation and handling steps were identified. Coagulase positive, enterotoxigenic Staphylococcus aureus, subspecies aureus was detected in a piece of cake, with a count of 2.4x10(6) CFU/g, and in samples from the hands and nostrils of three people involved in food preparation and service. The strains isolated from both the cake and one of the food handlers carried the sea gene, and presented the same SmaI-PFGE pattern. The foodborne disease outbreak was considered to be due to contamination in the preparation process of the cake consumed at the feast, which was related to inadequate hygienic conditions, lack of refrigeration and cold chain disruption.
Assuntos
Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Surtos de Doenças , Contaminação de Alimentos , Gastroenterite/epidemiologia , Intoxicação Alimentar Estafilocócica/epidemiologia , Argentina/epidemiologia , Técnicas de Tipagem Bacteriana , Estudos de Casos e Controles , Portador Sadio/metabolismo , Manipulação de Alimentos , Gastroenterite/etiologia , Gastroenterite/microbiologia , Refrigeração , Intoxicação Alimentar Estafilocócica/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificaçãoRESUMO
In the summer of 2006, an epidemic outbreak of acute gastrointestinal illness related to food consumption occurred in a small town in the province of Neuquén, Argentina. During a popular feast, approximately 800 local residents attended lunch held in the facilities of the Municipal Gymnasium. About three hours later, nearly 150 attendees sought medical assistance at the local hospital due to acute gastroenteritis. A case-control epidemiological investigation was conducted using representative non-probability sampling. The epidemiological investigation showed a common-source foodborne disease outbreak with a case-control ratio of 1:1.8. The main symptoms were abdominal cramps (88%), vomiting (73.5%) and diarrhea (60%). The cake was identified as the source of infection (OR 9.79; IC 95%, 2.66-36.00; p = 0.0001), and unsatisfactory hygienic conditions in food production, conservation and handling steps were identified. Coagulase positive, enterotoxigenic Staphylococcus aureus, subspecies aureus was detected in a piece of cake, with a count of 2.4 x 10(6) CFU/g, and in samples from the hands and nostrils of three people involved in food preparation and service. The strains isolated from both the cake and one of the food handlers carried the sea gene, and presented the same Smal-PFGE pattern. The foodborne disease outbreak was considered to be due to contamination in the preparation process of the cake consumed at the feast, which was related to inadequate hygienic conditions, lack of refrigeration and cold chain disruption.
Assuntos
Surtos de Doenças , Contaminação de Alimentos , Gastroenterite/epidemiologia , Intoxicação Alimentar Estafilocócica/epidemiologia , Adolescente , Adulto , Idoso , Argentina/epidemiologia , Técnicas de Tipagem Bacteriana , Portador Sadio/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Manipulação de Alimentos , Gastroenterite/etiologia , Gastroenterite/microbiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Refrigeração , Intoxicação Alimentar Estafilocócica/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificaçãoRESUMO
In this report we describe the detection and duration of fecal shedding of Shiga toxin-producing Escherichia coil (STEC) O157 and non-O157 in symptomatic and asymptomatic cases during four events occurred among children in day-care centers in Argentina. In each event, the cases were identified among children, family contacts and staff members of the Institution. The isolates were characterized by pheno-genotyping and subtyping methods. The STEC fecal shedding was prolonged and intermittent. Strains O157:H7 (1st event); O26:H11 (2nd event); O26:H11 (3rd event) and O145:NM (4th event) were shed during 23-30, 37, 31 and 19 days, respectively. Considering the possibility of STEC intermittent long-term shedding, symptomatic and asymptomatic individuals should be excluded from the Institution until two consecutive stool cultures obtained at least 48 h apart, test negative.
Assuntos
Diarreia Infantil/microbiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Toxinas Shiga/análise , Adulto , Argentina/epidemiologia , Cuidadores/estatística & dados numéricos , Criança , Pré-Escolar , Diarreia Infantil/epidemiologia , Surtos de Doenças , Transmissão de Doença Infecciosa , Escherichia coli/classificação , Escherichia coli/metabolismo , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/transmissão , Escherichia coli O157/isolamento & purificação , Escherichia coli O157/metabolismo , Saúde da Família , Feminino , Síndrome Hemolítico-Urêmica/epidemiologia , Síndrome Hemolítico-Urêmica/microbiologia , Humanos , Lactente , Masculino , Fatores de TempoRESUMO
Hace referencia a un estudio de caso sobre un brote de toxi-infección alimentaria asociada al consumo de leche ultrapasteurizada que tiene el objetivo de caracterizaral agente etiológico, se estima que las personas efectadas fueron 900, de las cuales 292 requirieron atención médica. El estudio se realizó con muestras de materia fecal de 12 pacientes, secreción nasal de 5 operarios de la planta y 3 muestras de leche, el resultado del estudio dió a la leche como vehículo de la toxi-infección y a un operario de la linea de producción como origen de la contimación de más de 50.000 litros de leche
Assuntos
Doenças Transmitidas por Alimentos/microbiologia , Intoxicação Alimentar Estafilocócica/microbiologia , ParaguaiRESUMO
Shiga toxin producing-Escherichia coli (STEC), an important emerging foodborne pathogen, has been associated with bloody and non-bloody diarrhea, hemorrhagic colitis, hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura. The cattle have been shown to be a major reservoir of STEC and raw foods such as ground beef and milk are the most common vehicles of infection. In the present study, the prevalence of STEC in 95 samples of frozen hamburgers and in 114 samples of soft cheese was established in 8.4% and 0.9%, respectively. The genotypic and phenotypic characteristics of the strains were determined. The virulence genes stx1, stx2, eaeA and EHEC-hlyA were identified by PCR and by colony blot hybridization assays. Serotyping, antimicrobial susceptibility and production of Stx using specific cytotoxicity assays on Vero cells were also determined. All STEC strains were characterized as eaeA-/EHEC-hlyA+. The stx2 genotype was prevalent (77.8%), and four different O:H serotypes were found, comprising: O8:H19 (5 strains), O113:H21 (1), O8:H16 (1), and O39:H49 (1). One STEC strain was nontypable. Although soft cheese complimented the microbiological quality controls for the coliform counts, the detection of STEC in one sample raises doubts concerning the effectiveness of the current quality controls. These data contribute to the implementation of strategies for the prevention and control of HUS.
Assuntos
Queijo/microbiologia , Escherichia coli/isolamento & purificação , Contaminação de Alimentos , Microbiologia de Alimentos , Carne/microbiologia , Toxina Shiga I/biossíntese , Toxina Shiga II/biossíntese , Adesinas Bacterianas/biossíntese , Adesinas Bacterianas/genética , Animais , Argentina , Toxinas Bacterianas/biossíntese , Toxinas Bacterianas/genética , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Bovinos , Chlorocebus aethiops , Criopreservação , Resistência a Medicamentos/genética , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Proteínas de Escherichia coli/biossíntese , Inspeção de Alimentos , Conservação de Alimentos , Genótipo , Proteínas Hemolisinas/biossíntese , Fenótipo , Toxina Shiga I/genética , Toxina Shiga II/genética , Células Vero , Virulência/genéticaRESUMO
Shiga toxin producing-Escherichia coli (STEC), an important emerging foodborne pathogen, has been associated with bloody and non-bloody diarrhea, hemorrhagic colitis, hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura. The cattle have been shown to be a major reservoir of STEC and raw foods such as ground beef and milk are the most common vehicles of infection. In the present study, the prevalence of STEC in 95 samples of frozen hamburgers and in 114 samples of soft cheese was established in 8.4
and 0.9
, respectively. The genotypic and phenotypic characteristics of the strains were determined. The virulence genes stx1, stx2, eaeA and EHEC-hlyA were identified by PCR and by colony blot hybridization assays. Serotyping, antimicrobial susceptibility and production of Stx using specific cytotoxicity assays on Vero cells were also determined. All STEC strains were characterized as eaeA-/EHEC-hlyA+. The stx2 genotype was prevalent (77.8
), and four different O:H serotypes were found, comprising: O8:H19 (5 strains), O113:H21 (1), O8:H16 (1), and O39:H49 (1). One STEC strain was nontypable. Although soft cheese complimented the microbiological quality controls for the coliform counts, the detection of STEC in one sample raises doubts concerning the effectiveness of the current quality controls. These data contribute to the implementation of strategies for the prevention and control of HUS.
RESUMO
Between February and May 2000, 279 meat samples were collected from 136 retail stores in Gualeguaychú City, Argentina. Samples were assayed for Escherichia coli O157:H7 by selective enrichment in modified EC broth containing novobiocin, followed by immunomagnetic separation (IMS) and plating onto both sorbitol MacConkey agar supplemented with cefixime and potassium tellurite and a chromogenic medium. Eleven E. coli O157:H7 isolates were detected in 6 (3.8%) of 160 ground beef samples, in 4 (4.8%) of 83 fresh sausages, and in 1 (3.3%) of 30 dry sausages. E. coli O157:H7 was not isolated from five hamburger patties or one barbecue-type fresh sausage assayed. The isolates were tested for virulence-related genes. Ten additional Shiga toxin-producing E. coli (STEC) O157:H7 isolates of food origin, recovered from different locations in Argentina, were included for comparison purposes. All 21 isolates harbored both eae and EHEC-hlyA genes, and 12 (57.1%) encoded stx2/stx2vh-a. The isolates were of phage types 87 (seven strains), 14 (four strains), 4 (three strains), and 26 (one strain). Six strains were nontypable by phage typing. Pulsed-field gel electrophoresis (PFGE) revealed 19 XbaI-PFGE profiles. Fifteen (71%) strains were grouped in four clusters, which shared more than 80% of DNA restriction fragments. The enrichment culture method with IMS was a sensitive procedure to detect E. coli O157:H7 strains in retail meats. Some of the isolates from different stores presented a high clonal relatedness, as determined by XhaI-PFGE and phage typing, and harbored the virulence factors associated with human illness.