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Sample records for brotes por norovirus

  1. BROTES POR NOROVIRUS EN RESIDENCIAS Y CENTROS SANITARIOS DE CATALUÑA

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    Pere Godoy

    2009-01-01

    Full Text Available Fundamentos. La baja dosis infectiva y las múltiples vías de transmisión facilitan la presentación de brotes de norovirus. El objetivo fue comparar la incidencia de brotes por norovirus en hospitales y residencias en Cataluña. Métodos. Se realizó un estudio descriptivo de la serie de brotes de norovirus en el período del 15/10/2004 al 30/10/2005. Se rellenó una encuesta epidemiológica para cada brote. Las variables fueron: número de expuestos, enfermos, mecanismo de transmisión, ámbito (centros sanitarios o residencias, región sanitaria, mes del año, y duración. Mediante técnicas de PCR se investigó la presencia de norovirus en muestras clínicas. Se calculó la incidencia en cada centro y la incidencia anual de brotes por centros. Las diferencias se determinaron con la prueba de c2 y la t de Student con un grado de significación (p inferior a 0,05. Resultados. Se detectaron 17 brotes, 6 en centros sanitarios y 11 en residencias. La tasa de ataque global fue del 33,4% (652/1951 y fue ligeramente superior en las residencias (35,2% que en los centros sanitarios (31,4%. El 94,1% (16/17 de los brotes se produjeron por transmisión persona a persona y sólo el 5,9% (1/17 por alimentos. La media de días entre el primer y último caso del brote fue de 11,4 (DE = 6,9. La duración media de los síntomas fue de 2,39 días (SD=1,6 y también fue superior en los pacientes hospitalizados 2,63 (SD=1,7 en comparación a los pacientes de residencias 1,97 (SD=1,7 (p < 0,0001. Conclusiones. Norovirus es responsable de un número importante de brotes por transmisión persona a persona. Se debe protocolizar su control para reducir su número y su duración.

  2. Brote de infección por norovirus del Grupo II en un centro de entrenamiento militar, Perú 2013

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    Mariana Ramos

    Full Text Available Reportamos un brote de norovirus (NoV ocurrido en un centro de entrenamiento militar peruano. Trece muestras de heces tomadas de casos iniciales resultaron positivas a NoV GII por RT-PCR. Se realizó un estudio caso-control para determinar factoresasociados a la infección. Se identificó 164 casos probables(tasa de ataqueclínica: 45,2%. El único factor asociado a la infecciónfue el "haber compartido habitación con un caso" (ORa=1,7; IC95% 1,1 a 2,7. Los hallazgos epidemiológicos sugieren que el virus fue propagado persona a persona. Futuras investigaciones de brotes de diarrea en el Perú deberían considerar al NoV como un agente etiológico

  3. Brote de norovirus en Mallorca asociado al consumo de ostras Norovirus outbreak in Majorca (Spain) associated with oyster consumption

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    Antònia Galmés Truyols; Jaume Giménez Duran; Antonio Nicolau Riutort; Gabriel Arbona Cerdá; Catalina Bosch Isabel; Margarita Portell Arbona; Joana Vanrell Berga

    2011-01-01

    Se describe la investigación de un brote de gastroenteritis por norovirus asociado al consumo de ostras. Se encuestaron 346 expuestos (266 afectados). Solamente se enviaron 14 muestras de heces de pacientes al Centro Nacional de Microbiología. Se mandaron ostras recogidas en el lugar de producción al Centro Nacional de Alimentación. Las ostras cumplían los parámetros microbiológicos de calidad aplicables antes de la comercialización, que no incluyen investigación de virus. El análisis epidemi...

  4. Brote de norovirus en Mallorca asociado al consumo de ostras Norovirus outbreak in Majorca (Spain associated with oyster consumption

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    Antònia Galmés Truyols

    2011-04-01

    Full Text Available Se describe la investigación de un brote de gastroenteritis por norovirus asociado al consumo de ostras. Se encuestaron 346 expuestos (266 afectados. Solamente se enviaron 14 muestras de heces de pacientes al Centro Nacional de Microbiología. Se mandaron ostras recogidas en el lugar de producción al Centro Nacional de Alimentación. Las ostras cumplían los parámetros microbiológicos de calidad aplicables antes de la comercialización, que no incluyen investigación de virus. El análisis epidemiológico asoció la aparición de la enfermedad al consumo de ostras (odds ratio [OR]=60,4; intervalo de confianza del 95% [IC95%]: 26,2-139,3 y de navajas (OR=3,13; IC95%: 1,4-6,9. Los análisis microbiológicos identificaron norovirus en los afectados, pero no en las ostras que habían estado sometidas a un tiempo mayor de depuración que las consumidas. Es necesario un control riguroso de los alimentos de especial riesgo para la transmisión de norovirus y disponer de recursos de laboratorio para investigar brotes alimentarios por norovirus.We describe investigation into an outbreak of norovirus gastroenteritis associated with oyster consumption. A survey was conducted in 346 exposed persons, 266 of whom were cases. Only 14 feces samples from patients were sent to the National Microbiology Laboratory. Oysters collected at the production site were sent to the National Food Center. The oysters met the microbiological quality standard required before sale, which did not include virus investigation. Epidemiological analysis showed an association between gastroenteritis and consumption of oysters (OR=60.4; 95% CI: 26.2-139.3 and razor shells (OR=3.13; 95% CI: 1.4-6.9. Microbiological analysis confirmed norovirus in affected individuals but not in the oysters that had been tested after a longer purification period than those consumed. Food with a special risk of norovirus transmission should be strictly monitored. Investigators should dispose of the

  5. Brote por Salmonella enteritidis en una residencia de ancianos

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    Yáñez Ortega Jose Luis; Carramiñana Martínez Isabel; Bayona Ponte Mercedes

    2001-01-01

    Fundamento: Se describe un brote de gastroenteritis por Salmonella Enteritidis, fagotipo 1, declarado en una residencia de ancianos de Burgos el 15 de noviembre de 1999. El objetivo de la investigación del brote ha sido determinar la fuente de infección, el mecanismo de transmisión y proponer las medidas adecuadas para evitar la recurrencia del problema. Métodos: Se ha realizado un estudio observacional de cohortes retrospectivo encuestando a 106 de un total de 119 reside...

  6. BROTE POR SALMONELLA ENTERITIDIS EN UNA RESIDENCIA DE ANCIANOS

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    José Luis Yáñez Ortega

    2001-01-01

    Full Text Available Fundamento: Se describe un brote de gastroenteritis por Salmonella Enteritidis, fagotipo 1, declarado en una residencia de ancianos de Burgos el 15 de noviembre de 1999. El objetivo de la investigación del brote ha sido determinar la fuente de infección, el mecanismo de transmisión y proponer las medidas adecuadas para evitar la recurrencia del problema. Métodos: Se ha realizado un estudio observacional de cohortes retrospectivo encuestando a 106 de un total de 119 residentes y a 9 trabajadores del centro. Se ha estimado el Riesgo Relativo de enfermar en función del consumo de diversos alimentos. Se ha utilizado la Regresión Logística para calcular las odds ratio ajustadas por edad, sexo y por el consumo de alimentos y vino. Se ha estudiado la concordancia del diagnóstico clínico frente al diagnóstico por coprocultivo mediante el índice de concordancia Kappa de Cohen. Resultados: Un total de 42 personas refirieron sintomatología (37 residentes y 5 empleados. La tasa de ataque clínico fue de 36,5 %. De 91 coprocultivos realizados (82 en residentes y 9 en empleados 45 resultaron positivos (41 en residentes y 4 en empleados. La Tasa de ataque de casos confirmados por coprocultivo fue de 49,5% en los investigados. La leche frita ha sido el alimento implicado epidemiológicamente con la aparición del brote: RR: 3,25 (IC95% 1,10-9,59. El efecto protector del vino (Odds Ratio: 0,68 no alcanzó significación estadística (p=0,36. El índice Kappa resultó 0,43 (p < 0,001, lo que demuestra la escasa concordancia del diagnóstico clínico frente al diagnóstico mediante coprocultivo. Conclusiones: Existe evidencia epidemiológica de que el consumo de leche frita ha sido el mecanismo de transmisión de la infección, y la conservación a temperatura inadecuada del alimento ha sido el factor contribuyente determinante en la eclosión del brote. Esto demuestra que lo más idóneo para prevenir este tipo de brotes son las prácticas y h

  7. Brote por Salmonella enteritidis en una residencia de ancianos

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    Yáñez Ortega Jose Luis

    2001-01-01

    Full Text Available Fundamento: Se describe un brote de gastroenteritis por Salmonella Enteritidis, fagotipo 1, declarado en una residencia de ancianos de Burgos el 15 de noviembre de 1999. El objetivo de la investigación del brote ha sido determinar la fuente de infección, el mecanismo de transmisión y proponer las medidas adecuadas para evitar la recurrencia del problema. Métodos: Se ha realizado un estudio observacional de cohortes retrospectivo encuestando a 106 de un total de 119 residentes y a 9 trabajadores del centro. Se ha estimado el Riesgo Relativo de enfermar en función del consumo de diversos alimentos. Se ha utilizado la Regresión Logística para calcular las odds ratio ajustadas por edad, sexo y por el consumo de alimentos y vino. Se ha estudiado la concordancia del diagnóstico clínico frente al diagnóstico por coprocultivo mediante el índice de concordancia Kappa de Cohen. Resultados: Un total de 42 personas refirieron sintomatología (37 residentes y 5 empleados. La tasa de ataque clínico fue de 36,5 %. De 91 coprocultivos realizados (82 en residentes y 9 en empleados 45 resultaron positivos (41 en residentes y 4 en empleados. La Tasa de ataque de casos confirmados por coprocultivo fue de 49,5% en los investigados. La leche frita ha sido el alimento implicado epidemiológicamente con la aparición del brote: RR: 3,25 (IC95% 1,10-9,59. El efecto protector del vino (Odds Ratio: 0,68 no alcanzó significación estadística (p=0,36. El índice Kappa resultó 0,43 (p<0,001, lo que demuestra la escasa concordancia del diagnóstico clínico frente al diagnóstico mediante coprocultivo. Conclusiones: Existe evidencia epidemiológica de que el consumo de leche frita ha sido el mecanismo de transmisión de la infección, y la conservación a temperatura inadecuada del alimento ha sido el factor contribuyente determinante en la eclosión del brote. Esto demuestra que lo más idóneo para prevenir este tipo de brotes son las prácticas y h

  8. Brote causado por Escherichia coli en Chalco, México

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    Cortés-Ortiz Iliana Alejandra

    2002-01-01

    Full Text Available Objetivo. Identificar el agente causal del brote de diarrea asociado con el desbordamiento del canal de aguas negras en Chalco. Material y métodos. Estudio retrospectivo y transversal, efectuado en el Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE, de la Secretaría de Salud, con 1 550 hisopos rectales para el aislamiento e identificación bioquímica de V. cholerae y enterobacterias, obtenidos de la población del Valle de Chalco, que presentó diarrea y vómito durante el desastre natural acontecido el 31 de mayo de 2000. El análisis de los resultados se efectuó por la diferencia entre las proporciones de dos poblaciones (prueba de Ji cuadrada. Las cepas de E. coli se hibridaron por "colony blot" para los grupos ETEC, EIEC, EPEC y EHEC. Resultados. El 0.45% correspondió a Salmonella: S. agona, S. infantis, S. enteritidis, S. muenchen, S. typhimurium; 0.06% a Shigella flexneri 3a, y 76.6% a E. coli: 62.2% a ETEC (44.6 % con LT, 11.2% con ST, y 44.1% con ambas sondas, 0.84% a EIEC (sonda ial, 0.84% a EPEC (sonda bundle-forming pilus BFP, 0.08% a E. coli enterohemorrágica no-O157:H7 (sonda pCVD419, y 36.02% no hibridó. No se encontró asociación entre E. coli patógena con la edad y género. Conclusiones. Escherichia coli podría ser responsable del brote de diarrea. Es importante conocer el agente etiológico del brote para encaminar las estrategias en el estudio y control sanitario del mismo.

  9. ESTUDIO CLÍNICO-EPIDEMIOLÓGICO DE LOS BROTES DE GASTROENTERITIS VÍRICAS EN CATALUÑA

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    Nuria Torner

    2009-01-01

    74 de 180 en los brotes de gastroenteritis de etiología conocida, el segundo agente causal es norovirus (33,3%; 60 de 180. El mayor conocimiento de las características y de las ventajas de los métodos moleculares en el diagnóstico de dichos brotes se ha traducido en un descenso en número de brotes de gastroenteritis de cualquier etiología y en especial a las causadas por norovirus.

  10. Brote por Salmonella enteritidis en trabajadores de un hospital

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    Chávez-de la Peña Ma. Eugenia

    2001-01-01

    Full Text Available Objetivo. Describir y determinar las causas de un brote de enfermedad gastrointestinal por Salmonella enteritidis, ocurrido en junio de 1998, entre el personal trabajador de la salud (TS que labora en un hospital de tercer nivel de atención, en la ciudad de México. Material y métodos. Se incluyó a todo aquel empleado que presentó diarrea o fiebre asociada a síntomas gastrointestinales, a partir del día 8 de junio de ese año, posterior a la ingestión de alimentos en el comedor del hospital (caso, y en aquellos asintomáticos (controles que ingirieron alimentos durante el mismo periodo y en el mismo lugar. Se les aplicó un cuestionario para conocer los alimentos ingeridos, se realizó hemocultivo a sujetos con fiebre mayor de 38 °C y coprocultivo a todos, incluido el personal de la cocina. En el análisis estadístico se utilizó razón de momios (RM, intervalos de confianza al 95% (IC 95%, ji cuadrada y valor de p= 0.05 para conocer la significancia estadística. Resultados: Desarrollaron síntomas 155 TS, y de éstos 129 completaron la encuesta; se encuestaron además 150 TS asintomáticos. Los síntomas más comunes fueron diarrea (85%, dolor abdominal (84%, cefalea (81.4%, náusea (78.3% y escalofríos (74.4%. Ocho hemocultivos fueron negativos; 59 casos (46% y seis controles (4% tuvieron coprocultivos positivos a Salmonella enteritidis. De los alimentos ingeridos, las tortas de carne capeadas con huevo (RM 19.39, IC 95% 9.09-41.4, la crema de mamey, así como el yogur fueron significativamente más frecuentes en casos que en controles. Los cultivos de los alimentos resultaron negativos. Conclusión. Muy probablemente este brote se debió a la ingestión de alimentos contaminados (tortas preparadas con huevo, papa y carne con insuficiente cocción. Este brote enfatiza la necesidad de mantener un programa de evaluación de la calidad de los alimentos en hospitales. El texto completo en inglés de este artículo está disponible en

  11. BROTES DE GASTROENTERITIS AGUDA VÍRICA EN RESIDENCIAS DE ANCIANOS. SISTEMA DE DETECCIÓN POR UMBRAL DE PREVALENCIA (SIDUP

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    Juan B Bellido-Blasco

    2009-01-01

    Full Text Available Se describen las intervenciones llevadas a cabo en una unidad de epidemiología local, durante varios años, relacionadas con la epidemiología de la gastroenteritis por norovirus en residencias de ancianos de Castellón. Desde varios brotes acaecidos en un mismo geriátrico, hasta el estudio de los casos esporádicos que determinan la situación endémica en varias residencias. Este trabajo se centra en el análisis de esa situación endémica de síntomas digestivos en periodos de silencio epidémico y la propuesta de un método sencillo para detectar el inicio de brotes de GEA de transmisión progresiva (persona- persona que hemos denominado Sistema de Detección por Umbral de Prevalencia (SiDUP. Se discute el espectro epidemiológico de la gastroenteritis por norovirus en estas instituciones para personas mayores.

  12. Signos Vitales de los CDC Cómo prevenir los brotes de norovirus (Vital Signs-Preventing Norovirus Outbreaks)

    Centers for Disease Control (CDC) Podcasts

    2014-06-03

    Este podcast se basa en la edición de junio del 2014 del informe Signos Vitales de los CDC. Los norovirus infectan cada año a cerca de 20 millones de personas en los Estados Unidos. Sepa cómo protegerse y proteger a su familia de esta enfermedad que es muy contagiosa y potencialmente grave.  Created: 6/3/2014 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 6/3/2014.

  13. Brote de faringo-amigdalítis por estreptococo ?-hemolítico grupo A

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    Dante R Culqui; Sandra Manzanares-Laya; Sarah Lafuente Van Der Sluis; Albert Anton Fanlo; Rosa Bartolomé Comas; Marcello Rossi; Joán A Caylá

    2014-01-01

    El objetivo fue describir un brote de faringo-amigdalitis causado por estreptococos β-hemolíticos del grupo A (EGA) en profesionales de la salud. El estudio que se transmite de persona-persona o por vía alimentaria. El estudio transversal descriptivo se realizó en 17 clientes, localizados en la misma mesa, que participaron de una cena en restaurante de Barcelona, España, en julio de 2012. Se analizaron, la frecuencia de síntomas de los afectados, el tiempo y la s...

  14. Brote de gastroenteritis por agua potable de suministro público

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    Godoy P.

    2003-01-01

    Full Text Available Introducción: La potabilidad del agua induce a descartar el posible origen hídrico de los brotes. El objetivo fue investigar un brote de gastroenteritis por agua potable de suministro público. Métodos: Después de la notificación de un brote de gastroenteritis en el municipio de Baqueira (Valle de Arán se diseñó un estudio epidemiológico de cohortes retrospectivo. Mediante un muestreo sistemático se eligió a 87 personas hospedadas en los hoteles y a 62 alojadas en diferentes apartamentos. Se recogió información sobre 4 factores (consumo de agua de la red, bocadillos, agua y alimentos en las pistas de esquí y presencia de síntomas. Se determinó la existencia de cloro, se analizó el agua de la red y se realizó un coprocultivo a 4 enfermos. La implicación de cada factor se determinó con el riesgo relativo (RR y su intervalo de confianza (IC del 95%. Resultados: La incidencia de gastroenteritis fue del 51,0% (76/149. Los porcentajes de los síntomas fueron los siguientes: fiebre, 27,0%; diarrea, 87,5%; náuseas, 50,7%; vómitos, 30,3%, y dolor abdominal, 80,0%. El único factor que presentó un riesgo estadísticamente significativo fue el consumo de agua de la red (RR = 11,0; IC del 95%, 1,6-74,7. La calificación sanitaria del agua fue de potabilidad. Se observó un defecto de situación del clorador en el depósito, que fue corregido. Se recomendó incrementar aún más las concentraciones de cloro, lo cual se acompañó de una disminución de los casos. Los coprocultivos de los 4 enfermos fueron negativos para las enterobacterias investigadas. Conclusiones: El estudio demuestra la posibilidad de presentación de brotes hídricos por agua cualificada como potable y sugiere la necesidad de mejorar la investigación microbiológica (determinación de protozoos y virus en este tipo de brotes.

  15. Brote de gastroenteritis por virus Norwalk en una residencia de ancianos de Granada

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    Almagro Nievas Diego

    2003-01-01

    Full Text Available Fundamento: Los brotes de gastroenteritis aguda de origen vírico son actualmente uno de los problemas de salud que más están afectando a las personas residentes en instituciones de la tercera edad. El objetivo del estudio es investigar las causas del origen y transmisión de un brote de gastroenteritis aguda por virus Norwal-Like. Método: En una residencia de ancianos con 141 residentes y 71 trabajadores expuestos, se investigó la relación entre un brote de gastroenteritis aguda y distintas variables: características personales, de lugar, fecha de inicio de los síntomas, clínica de la enfermedad y factores causales (alimentos y agua de consumo. Se realizó un estudio descriptivo, tabla de contingencia y test de hipótesis 2, diseño de casos y controles con el calculo de Odds Ratio cruda y posteriormente ajustada (IC al 95% utilizando regresión logística. Resultados: No se observaron diferencias significativas en las variables de características personales y de lugar. La tasa de ataque en los residentes fue del 30,1% y en trabajadores fue del 21,12%. En el calculo de la Odds Ratio ajustada sólo tuvo valores de relación causal la mousse de nata (Odds Ratio ajustada=4,66; IC-95% 1,15-18,91; p=0,031. Se remitieron 10 muestras de heces de enfermos para su análisis, no detectándose ninguna bacteria patógena, pero si se aisló en 3 de ellas virus Norwal-Like. Conclusiones: El hallazgo de la mousse de nata como posible responsable del brote supone una primicia en la presencia de virus Norwalk, pero este resultado está sujeto a limitaciones, como el posible sesgo de clasificación por no recuerdo de consumo de alimentos. Aún así, supone un elemento a tener en cuenta en el control de gastroenteritis agudas por virus.

  16. Brote de faringoamigdalitis de origen alimentario por estreptococo betahemolítico A

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    Juan Nieto Vera

    2011-01-01

    Full Text Available Fundamento: Aunque no son frecuentes, algunos autores han comunicado brotes de faringoamigdalitis de origen alimentario. El 11 de mayo de 2010 se notificó a la Red de Vigilancia Epidemiológica de Andalucía (SVEA que había personas con cuadro de faringoamigdalitis que tenían en común haber asistido a una comunión celebrada el día 8. El objetivo de este trabajo es la caracterización epidemiológica del brote. Método: Estudio observacional descriptivo de casos notificados y análisis de casos control por exposición a los alimentos implicados. Se analizaron las variables edad, sexo, sintomatología y fecha de inicio de síntomas. Fuentes de información fueron los registros del SVEA e historia digital individual (DIRAYA. Se calcularon frecuencias, tasas de ataque, y análisis bayesiano de comparación de diferencia de proporciones de enfermar para un intervalo de probabilidad o credibilidad (IP del 95%. Resultados: De 130 asistentes a una celebración se detectaron 41 casos de faringoamigdalitis (tasa ataque 31,5% y se aisló en frotis Estreptococo betahemolítico A. El grupo de edad más afectado fue el de 25-44 años: 16 (39,0%;hubo más afectación de las mujeres 24 (68,6% mujeres. La ensaladilla de huevo presentó una probabilidad mayor del 80% P(Δ>0,10 y Δ>0,15 para un IP del 95% de enfermar tras su consumo y la probabilidad de tener menos riesgo de no enfermar. Conclusiones: Se trató de un brote por estreptococo betahemolítico A. El análisis epidemiológico evidenció exposición a fuente única y común, siendo plausible la hipótesis del origen alimentario, posiblemente por la ensaladilla de huevo contaminada por algún manipulador de alimentos. Como factores contribuyentes se identificaron inadecuadas medidas higiénico-sanitarias en la manipulación y conservación de los alimentos.

  17. BROTE DE GASTROENTERITIS POR VIRUS NORWALK EN UNA RESIDENCIA DE ANCIANOS DE GRANADA

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    Diego Almagro Nievas

    2003-01-01

    Full Text Available vírico son actualmente uno de los problemas de salud que más están afectando a las personas residentes en instituciones de la tercera edad. El objetivo del estudio es investigar las causas del origen y transmisión de un brote de gastroenteritis aguda por virus Norwal- Like. Método: En una residencia de ancianos con 141 residentes y 71 trabajadores expuestos, se investigó la relación entre un brote de gastroenteritis aguda y distintas variables: características personales, de lugar, fecha de inicio de los síntomas, clínica de la enfermedad y factores causales (alimentos y agua de consumo. Se realizó un estudio descriptivo, tabla de contingencia y test de hipótesis 2, diseño de casos y controles con el calculo de Odds Ratio cruda y posteriormente ajustada (IC al 95% utilizando regresión logística. Resultados: No se observaron diferencias significativas en las variables de características personales y de lugar. La tasa de ataque en los residentes fue del 30,1% y en trabajadores fue del 21,12%. En el calculo de la Odds Ratio ajustada sólo tuvo valores de relación causal la mousse de nata (Odds Ratio ajustada=4,66; IC-95% 1,15- 18,91; p=0,031. Se remitieron 10 muestras de heces de enfermos para su análisis, no detectándose ninguna bacteria patógena, pero si se aisló en 3 de ellas virus Norwal-Like. Conclusiones: El hallazgo de la mousse de nata como posible responsable del brote supone una primicia en la presencia de virus Norwalk, pero este resultado está sujeto a limitaciones, como el posible sesgo de clasificación por no recuerdo de consumo de alimentos. Aún así, supone un elemento a tener en cuenta en el control de gastroenteritis agudas por virus.

  18. Brote de faringo-amigdalítis por estreptococo ?-hemolítico grupo A

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    Dante R Culqui

    2014-04-01

    Full Text Available El objetivo fue describir un brote de faringo-amigdalitis causado por estreptococos β-hemolíticos del grupo A (EGA en profesionales de la salud. El estudio que se transmite de persona-persona o por vía alimentaria. El estudio transversal descriptivo se realizó en 17 clientes, localizados en la misma mesa, que participaron de una cena en restaurante de Barcelona, España, en julio de 2012. Se analizaron, la frecuencia de síntomas de los afectados, el tiempo y la severidad de los síntomas, variables demográficas y alimentos ingeridos, entre otros factores. La tasa de ataque (TA en los comensales fue del 58,8% (10/17. El 60,0% (6/10 de los comensales fueron positivos para EGA. El 46,2% (6/13 de los manipuladores de alimentos suministrados en la cena presentaron síntomas. No se identificó asociación con los alimentos ingeridos. Existen evidencias epidemiológicas de la transmisión alimentaria del EGA, pero no podría descartarse la transmisión respiratoria.

  19. Brote de faringoamigdalitis de origen alimentario por estreptococo betahemolítico A

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    Juan Nieto Vera; Estrella Figueroa Murillo; María Victoria Cruz Calderón; Aránzazu Pérez Alonso

    2011-01-01

    Fundamento: Aunque no son frecuentes, algunos autores han comunicado brotes de faringoamigdalitis de origen alimentario. El 11 de mayo de 2010 se notificó a la Red de Vigilancia Epidemiológica de Andalucía (SVEA) que había personas con cuadro de faringoamigdalitis que tenían en común haber asistido a una comunión celebrada el día 8. El objetivo de este trabajo es la caracterización epidemiológica del brote. Método: Estudio observacional descriptivo de casos notificados y análisis de casos con...

  20. Brote de diarrea por Shigella en Coto Brus: Costa Rica,de octubre a diciembre del 2001

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    Azalea Espinoza Aguirre

    2005-07-01

    Full Text Available Introducción Coto Brus,cantón cafetalero localizado en la zona fronteriza con Panamá,reportó,en noviembre del 2001,dos defunciones en menores de un año por Shigella flexnnery ,debido a un brote de diarrea.Se inició la investigación para determinar la magnitud y el mecanismo de transmisión del brote y recomendar acciones para prevenir nuevos casos. Métodos Se revisaron 2862 hojas de consultas por diarrea en el Hospital de Coto Brus,de enero a noviembre del 2001,para caracterizar el brote.Se tomaron muestras de agua para el cultivo bacteriológico y coprocultivos.Para determinar el mecanismo de transmisión de Shigella ,se realizó un estudio caso-control.Un caso fue toda persona de Coto Brus,referida al hospital del lugar por diarrea y que presentó un coprocultivo positivo por Shigella ,del 1 ºal 15 diciembre del 2001. Se calcularon OR(IC95%a variables socio-laborales y condiciones higiénicas. Resultados De 29 coprocultivos enviados se aislaron 19 por Shigella flexneri. Factores de riesgo como: no lavarse las manos antes de comer presentó un OR=4,80;IC(1,28-18,73,para recolectores de café el OR=4,17(1,09-16,73y contactar con una persona con diarrea OR=4,36(IC95%=1,08- 18,27.Las muestras de agua no reportaron contaminación con el agente.La propagación persona a persona fue identificada como mecanismo de transmisión. Conclusiones Deficientes condiciones de saneamiento en las fincas cafetaleras y las malas prácticas higiénicas facilitaron la transmisión de Shigella entre los recolectores de café.Se recomendó supervisar la actividad cafetalera por los Ministerios de Salud y Trabajo para garantizar condiciones de saneamiento básicas y promover prácticas higiénicas en los trabadores durante la época de recolección del café.

  1. Brotes de diarrea e intoxicaciones transmitidas por alimentos en Costa Rica, 2005

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    Hilda Ma Bolaños-Acuña

    2007-10-01

    Full Text Available Justificación y objetivo: En la actualidad, las enfermedades de transmisión alimentaria, incluyendo las diarreas e intoxicaciones, constituyen uno de los problemas de salud pública de mayor importancia a nivel mundial, ya que ocasionan alta morbilidad y mortalidad, generan grandes costos a los servicios de salud, pérdidas económicas, demandas y pérdida de confianza de los consumidores. El objetivo del trabajo es analizar la información disponible en el Centro Nacional de Referencia en Bacteriología del INCIENSA (CNRB, de los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005, en los que se refirieron muestras clínicas o de alimentos, para identificar los agentes y vehículos de infección asociados. Materiales y métodos:Se realizó el análisis descriptivo de la información epidemiológica y de laboratorio disponible en el CNRB en relación con los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005. Resultados:Durante el período el CNRB documentó 23 brotes de diarrea e intoxicaciones alimentarias, para un total aproximado de 819 afectados, en su mayoría procedentes de la gran área metropolitana. Trece de los brotes fueron intrafamiliares (diez de ellos debidos a especies y serotipos de Shigella; sin embargo, el mayor número de enfermos se presentó en los brotes comunitarios y los que se produjeron en poblaciones cautivas, asociados a rotavirus, Escherichia coli enterotoxigénica y Clostridium perfringens productor de toxina A, con 518, 138 y 54 enfermos, respectivamente. Conclusión:Estos hallazgos evidencian deficiencias en la cadena de transporte, conservación y manipulación de los alimentos, así como en la higiene personal, y pueden ser de utilidad para la implementación de intervenciones inmediatas.

  2. Reflexión sobre los modelos para el estudio de los brotes de rabia humana por murciélago

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    Schneider Maria Cristina

    1995-01-01

    Full Text Available El presente trabajo es una reflexión sobre cuál de los posibles modelos en salud pública contribuiría más para el entendimiento de la ocurrencia de brotes de rabia humana transmitida por murciélagos. En un primer momento se hace una breve revisión sobre los modelos más utilizados para analizar nuestro objeto de estudio. Posteriormente se presenta la investigación de un brote de rabia humana transmitida por murciélagos con base en el modelo epidemiológico social. Este mismo brote se analiza nuevamente utilizando como marco teórico la teoría de sistemas complejos, como forma de un ejercicio teórico-práctico para intentar una aproximación a esta teoría, como un posible modelo para estudiar el problema presentado.

  3. BROTE EPIDÉMICO POR TOS FERINA EN ÉCIJA (SEVILLA, 2016

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    Miguel Porras-Povedano

    2017-01-01

    Full Text Available La tos ferina representa un problema de salud pública mundial, es una enfermedad muy contagiosa y, a pesar de la vacunación universal, se observa un aumento de incidencia. El objetivo de este estudio fue describir la investigación de un brote epidémico. Método: Estudio descriptivo de un brote poblacional de tos ferina entre febrero y junio de 2016 en Écija (Sevilla. Se utilizaron definiciones de caso y brote del Protocolo de Vigilancia de Tos ferina. Se recogió información de Historia de Salud, Sistema de Vigilancia Epidemiológica y Laboratorio. El análisis estadístico se realizó mediante software libre R, para variables cuantitativas se presentaron media, mediana, desviación estándar, valores mínimo y máximo y percentiles, para las variables cualitativas distribución de frecuencias. Resultados: Se identificó a 91 pacientes sospechosos, descartándose 33. Los 58 restantes se identificaron como casos, clasificándose 42 casos confirmados y 16 probables. Los casos presentaron una edad media de 10,24 años, siendo el 62,1% mujeres. La incidencia fue de 148,51 casos/100.000 habitantes de manera global y de 851,06 casos/100.000 habitantes en menores de 14 años. Todos los menores de 18 años estaban correctamente vacunados en primovacunación y a 2 niños les faltaba la quinta dosis. El tiempo medio entre inicio de síntomas y diagnóstico fue de 24,86 días. Conclusiones: Las medidas de vigilancia y control establecidas consiguieron limitar y resolver el brote. Se recomienda potenciar la información y coordinación entre los distintos niveles asistenciales (Atención Primaria/ Especializada y profesionales (Clínicos/Epidemiología.

  4. Brotes de diarrea e intoxicaciones transmitidas por alimentos en Costa Rica, 2005

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    Hilda Ma Bolaños-Acuña

    2007-10-01

    Full Text Available Justificación y objetivo: En la actualidad, las enfermedades de transmisión alimentaria, incluyendo las diarreas e intoxicaciones, constituyen uno de los problemas de salud pública de mayor importancia a nivel mundial, ya que ocasionan alta morbilidad y mortalidad, generan grandes costos a los servicios de salud, pérdidas económicas, demandas y pérdida de confianza de los consumidores. El objetivo del trabajo es analizar la información disponible en el Centro Nacional de Referencia en Bacteriología del INCIENSA (CNRB, de los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005, en los que se refirieron muestras clínicas o de alimentos, para identificar los agentes y vehículos de infección asociados. Materiales y métodos:Se realizó el análisis descriptivo de la información epidemiológica y de laboratorio disponible en el CNRB en relación con los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005. Resultados:Durante el período el CNRB documentó 23 brotes de diarrea e intoxicaciones alimentarias, para un total aproximado de 819 afectados, en su mayoría procedentes de la gran área metropolitana. Trece de los brotes fueron intrafamiliares (diez de ellos debidos a especies y serotipos de Shigella; sin embargo, el mayor número de enfermos se presentó en los brotes comunitarios y los que se produjeron en poblaciones cautivas, asociados a rotavirus, Escherichia coli enterotoxigénica y Clostridium perfringens productor de toxina A, con 518, 138 y 54 enfermos, respectivamente. Conclusión:Estos hallazgos evidencian deficiencias en la cadena de transporte, conservación y manipulación de los alimentos, así como en la higiene personal, y pueden ser de utilidad para la implementación de intervenciones inmediatas.Justification and objective:Food borne diseases ncluding diarrhea and food poisoning represent one of the major public health problems worldwide, since they cause high morbidity and mortality

  5. Brote causado por Escherichia coli en Chalco, México Outbreak caused by Escherichia coli in Chalco, México

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    Iliana Alejandra Cortés-Ortiz

    2002-07-01

    Full Text Available Objetivo. Identificar el agente causal del brote de diarrea asociado con el desbordamiento del canal de aguas negras en Chalco. Material y métodos. Estudio retrospectivo y transversal, efectuado en el Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE, de la Secretaría de Salud, con 1 550 hisopos rectales para el aislamiento e identificación bioquímica de V. cholerae y enterobacterias, obtenidos de la población del Valle de Chalco, que presentó diarrea y vómito durante el desastre natural acontecido el 31 de mayo de 2000. El análisis de los resultados se efectuó por la diferencia entre las proporciones de dos poblaciones (prueba de Ji cuadrada. Las cepas de E. coli se hibridaron por "colony blot" para los grupos ETEC, EIEC, EPEC y EHEC. Resultados. El 0.45% correspondió a Salmonella: S. agona, S. infantis, S. enteritidis, S. muenchen, S. typhimurium; 0.06% a Shigella flexneri 3a, y 76.6% a E. coli: 62.2% a ETEC (44.6 % con LT, 11.2% con ST, y 44.1% con ambas sondas, 0.84% a EIEC (sonda ial, 0.84% a EPEC (sonda bundle-forming pilus BFP, 0.08% a E. coli enterohemorrágica no-O157:H7 (sonda pCVD419, y 36.02% no hibridó. No se encontró asociación entre E. coli patógena con la edad y género. Conclusiones. Escherichia coli podría ser responsable del brote de diarrea. Es importante conocer el agente etiológico del brote para encaminar las estrategias en el estudio y control sanitario del mismo.Objective. To identify the etiologic agent responsible for a disease outbreak following an overflow of sewage water in Valle de Chalco, Mexico. Material and Methods. A retrospective cross-sectional study was carried out. Rectal samples were collected from the population of Chalco valley, who suffered from diarrhea and vomiting during a natural disaster that took place on May 31, 2000. The Instituto de Diagnóstico y Referencia Epidemiológicos (Epidemic Reference and Diagnosis Institute, InDRE, Ministry of Health, received 1521 rectal

  6. Estudio de un brote epidémico causado por distintas cepas de "Acinetobacter baumannii" multirresistente: estudio de la epidemicidad y virulencia

    OpenAIRE

    Merino Carballeira, María

    2016-01-01

    [Resumen] El patógenos oportunista Acinetobacter baumannii es uno de los seis microorganismos multirresistentes que más preocupa en hospitales de todo el mundo. Esto es debido a su capacidad para persistir en ambientes extremos, ya que es capaz de sobrevivir en el ambiente hospitalario, y a su versatilidad genética, ya que tiene la capacidad para desarrollar mecanismos de resistencia a antibióticos y desinfectantes. Múltiples brotes hospitalarios producidos por cepas de A. b...

  7. Brote por Salmonella enteritidis en trabajadores de un hospital An outbreak of Salmonella gastroenteritis among hospital workers

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    Ma. Eugenia Chávez-de la Peña

    2001-06-01

    Full Text Available Objetivo. Describir y determinar las causas de un brote de enfermedad gastrointestinal por Salmonella enteritidis, ocurrido en junio de 1998, entre el personal trabajador de la salud (TS que labora en un hospital de tercer nivel de atención, en la ciudad de México. Material y métodos. Se incluyó a todo aquel empleado que presentó diarrea o fiebre asociada a síntomas gastrointestinales, a partir del día 8 de junio de ese año, posterior a la ingestión de alimentos en el comedor del hospital (caso, y en aquellos asintomáticos (controles que ingirieron alimentos durante el mismo periodo y en el mismo lugar. Se les aplicó un cuestionario para conocer los alimentos ingeridos, se realizó hemocultivo a sujetos con fiebre mayor de 38 °C y coprocultivo a todos, incluido el personal de la cocina. En el análisis estadístico se utilizó razón de momios (RM, intervalos de confianza al 95% (IC 95%, ji cuadrada y valor de p= 0.05 para conocer la significancia estadística. Resultados: Desarrollaron síntomas 155 TS, y de éstos 129 completaron la encuesta; se encuestaron además 150 TS asintomáticos. Los síntomas más comunes fueron diarrea (85%, dolor abdominal (84%, cefalea (81.4%, náusea (78.3% y escalofríos (74.4%. Ocho hemocultivos fueron negativos; 59 casos (46% y seis controles (4% tuvieron coprocultivos positivos a Salmonella enteritidis. De los alimentos ingeridos, las tortas de carne capeadas con huevo (RM 19.39, IC 95% 9.09-41.4, la crema de mamey, así como el yogur fueron significativamente más frecuentes en casos que en controles. Los cultivos de los alimentos resultaron negativos. Conclusión. Muy probablemente este brote se debió a la ingestión de alimentos contaminados (tortas preparadas con huevo, papa y carne con insuficiente cocción. Este brote enfatiza la necesidad de mantener un programa de evaluación de la calidad de los alimentos en hospitales. El texto completo en inglés de este artículo está disponible en

  8. Implicaciones en la salud humana de la gastroenteritis aguda por norovirus como producto de la contaminación hídrica

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    Brenda Delgadillo Espinoza

    2011-05-01

    Full Text Available En julio del 2010, un brote de gastroenteritis Aguda surgió entre los residentes de la ciudad principal de la Región Norte de Costa Rica: Ciudad Quesada. Esta investigación se llevó a cabo para explorar y caracterizar el brote en esa zona rural. Los datos de vigilancia y los registros médicos de los pacientes fueron analizados para elaborar un estudio descriptivo entre el 08 de julio y 14 de julio del 2010 en el Cantón de San Carlos. Una hoja de datos (Ficha Colectiva de Investigación VE 0.2 fue aplicada para obtener información de los pacientes. Con el fin de detectar la presencia de enteropatógenos, una prueba de ELISA fue aplicada a las muestras de heces tomadas. Las muestras de agua también se analizaron para detectar bacterias y coliformes fecales en el sistema de distribución. Un total de 352 casos fueron confirmados en la región estudiada con la presencia de síntomas frecuentes entre los casos confirmados; estos síntomas fueron diarrea (94,2%, náuseas (92,7% y vómitos (91,7%. La edad media de los pacientes fue de 29 años (15,8 y el 50,8% correspondió a sujetos del sexo femenino. El grupo de edad más afectado es el representado por los lactantes de 1 a 4 años (tasa de ataque 18,2 / 1000 habitantes La zona con más afectación fue el área central de Ciudad Quesada. En cinco de cada seis pruebas de heces fue posible aislar el norovirus. Por otra parte, en las pruebas aplicadas al agua solo se identifica la presencia de Escherichia coli. Los resultados sugieren que el norovirus fue transmitido por agua contaminada con materia fecal. Este es el primer brote documentado que ha sido causado por este virus en la región norte del país. Se recomienda mejorar la vigilancia de la calidad del agua, promover el uso de agua potable entre los residentes, generar un plan de educación que fomente prácticas seguras de manejo y distribución de agua; así como campañas de sensibilización en comunidades rurales como ésta en temas

  9. Brote epidémico por consumo de pez mantequilla: keriorrea e intoxicación histamínica

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    Mª Azucena Fariñas Cabrero

    2015-01-01

    Full Text Available Fundamentos: El consumo de pez mantequilla se está extendiendo en nuestro país. Si no se cumplen unas adecuadas normas de conservación y preparación de este tipo de alimento puede producir intoxicaciones. El obje¬tivo del trabajo fue describir un brote de doble intoxicación por histamina y ésteres cerosos tras el consumo de pez mantequilla. Métodos: Estudio descriptivo de la doble intoxicación producida en un banquete celebrado en julio de 2013 en Valladolid. Se estudió mediante la cumplimentación de una encuesta específica telefónica o desde los centros asistenciales que atendieron a los comensales. La base de datos y posterior análisis estadístico descriptivo se realizaron con el programa Microsoft Ex¬cel Professional Plus 2010. Resultados. De los 27 casos declarados,en 24 se obtuvo información sobre los síntomas. La tasa de ataque fue 22,5%, con un cuadro clínico en el que predominó la diarrea (75%, la cefalea (46%, el dolor abdominal (38% y la sudoración (38%, destacando por su especificidad el picor/ardor de boca (29%. Cuatro pacientes presentaron heces anaranjadas y oleosas (keriorrhea. El tiempo medio transcurrido, desde el inicio de la cena hasta la aparición de los síntomas, fue de dos horas. La duración media de la sin¬tomatología fue de 14 horas. La analítica del pescado servido mostró niveles de histamina superiores a 2.000 mg/kg. Conclusiones. Se produjo una doble intoxicación (histamina y ésteres cerosos por consumo de pez mantequilla. El cuadro fue leve y autolimitado

  10. Brote de Fiebre Hemorrágica por el virus del Ébola en Uganda Hemorrhagic Fever outbreak due to Ebola virus in Uganda

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    MªC. Aríñez Fernández

    2012-03-01

    Full Text Available En Uganda se está llevando a cabo la Misión de la Unión Europea (EUTM Somalia, en la que participan efectivos de las Fuerzas Armadas españolas. En mayo de 2011 el Ministerio de Sanidad de Uganda notificó un brote de fiebre hemorrágica por el virus del bola a 70 km de distancia de Kampala. El caso índice y único caso confirmado, fue una niña de 12 años que falleció. La investigación epidemiológica se llevó a cabo por un equipo internacional que incluyó personal del Ministerio de Sanidad de Uganda y de la OMS. Tras mantener la vigilancia del brote durante un tiempo igual a dos veces el periodo de incubación y no confirmar otros casos, fue declarado finalizado el brote el 17 de junio de 2011. Se distribuyó información sobre el brote y recomendaciones de actuación tanto a profesionales de la salud como a la población general.The European Mission (EUTM Somalia is being conducted in Uganda. Military personnel of the Spanish Armed Forces participate in that mission. On 13 May 2011, The Ministry of Health of Uganda notified a case of Ebola hemorrhagic fever in a district 70 kilometers far from Kampala. The index case and only confirmed case, was a 12-year-old girl who finally died. Epidemiologic surveillance was conducted by an international team including representatives of the Ugandan Ministry of Health and WHO. The Ministry of Health of Uganda declared the end of the outbreak on the 17 June 2011, since the epidemiological investigations, including twofold the incubation period surveillance, did not confirm new cases. Guidelines to control the outbreak and information on the disease were distributed to health professionals and general population.

  11. Encefalitis por virus San Luis en la Ciudad de Buenos Aires durante el brote de dengue 2009

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    Horacio López

    2011-06-01

    Full Text Available Se presenta un paciente de 80 años de edad, residente en la Ciudad de Buenos Aires, con diagnóstico serológico para el virus de la encefalitis de San Luis (SLE durante el brote de dengue ocurrido entre enero y mayo de 2009. Presentaba leucemia linfoide crónica en tratamiento con clorambucilo, cáncer de próstata tratado con hormonoterapia y radioterapia, e imágenes óseas compatibles con metástasis. El estudio del líquido cefalorraquídeo demostró pleocitosis con predominio de mononucleares y proteinorraquia elevada. El resultado de los cultivos para bacterias, hongos y micobacterias, así como el PCR en LCR para herpes virus, HSV, CMV y EBV, fue negativo. Se detectaron anticuerpos IgM para virus SLE tanto en LCR como en muestra de suero, con seroconversión IgG por neutralización en cultivos celulares y resultados negativos para los demás Flavivirus con circulación en Argentina. Se revisan evidencias sobre la presencia de virus de San Luis en nuestro país, y se señala la importancia de la confirmación diagnóstica y el estudio de otros Flavivirus en casos sospechosos de dengue con presentación grave o atípica. Este trabajo remarca la necesidad de fortalecer tanto la vigilancia epidemiológica del virus SLE, como el control vectorial para prevenir las diferentes infecciones transmitidas por mosquitos y conocer su efecto en Salud Pública en la Argentina.

  12. Brote por pseudomonas aeruginosa, en el área de atención ambulatoria de heridas quirúrgicas, en pacientes posmastectomizadas

    OpenAIRE

    Vilar-Compte Diana; Jacquemin Benedicte; Díaz-González Adriana; Velásquez Consuelo; Volkow Patricia

    2003-01-01

    OBJETIVO: Describir un brote por Pseudomonas aeruginosa, en el área de atención ambulatoria de herida quirúrgica, en pacientes posmastectomizadas. MATERIAL Y MÉTODOS: Entre el 13 de marzo y el 18 de mayo de 2000 se definió como caso a las pacientes del Instituto Nacional de Cancerología de la Ciudad de México, mastectomizadas con infección quirúrgica por P aeruginosa resistente a ciprofloxacina y gentamicina. Se tomaron cultivos de los antisépticos, del material de curaciones, del agua y del ...

  13. Agentes bacterianos asociados a brotes de Enfermedades Trasmitidas por Alimentos (ETA) aislados de coprocultivos - Bacterial agents associated to foodborne outbreaks isolated from foods and faecal samples

    OpenAIRE

    Sedrés Cabrera, Martha; Barreto Argilagos, Guillermo; Guevara Viera, Guillermo; Rodríguez Torrens, Herlinda

    2010-01-01

    ResumenEl trabajo aborda la incidencia de agentes bacterianos, aislados decoprocultivos realizados a pacientes con diarreas agudas. Todos involucrados en 72 brotes de enfermedades transmitidas por alimentos (ETA) estudiados por el Centro Provincial de Higiene, Epidemiología y Microbiología “Mártires de Pino Tres” de la ciudad de Camagüey. A tal fin se procesó la información recogida en su Sección de Coprocultivos.Este estudio generó un total de 722 muestras de las cuales 279 (38,64%)posibilit...

  14. Brote de toxiinfección alimentaria por salmonella entérica en un establecimiento de restauración colectiva

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    Rosa Ma. Carbó Malonda

    2005-01-01

    Full Text Available Fundamento: Se describe un brote de toxiinfección alimentaria por Salmonella enteritidis ocurrido en dos salones de banquetes con ocho grupos de comensales afectados. El objeto de la investigación fue determinar el alimento vehículo de transmisión de la enfermedad. Métodos: Se analizaron los procesos de elaboración de los alimentos susceptibles de haber causado el brote. La asociación de los alimentos con la enfermedad se analizó mediante un diseño de casos y controles. Se calcularon las Odds Ratio ajustadas (ORa y sus intervalos de confianza al 95% (IC95% por regresión logística. Resultados: El número de comensales fue 1.771, distribuidos en 13 grupos durante tres días consecutivos. Se encuestó a 629 personas (36%. El número de casos probables fue de 250, 61 confirmados por salmonella enterica. El biscuit glasé (postre con huevo crudo sin tratamiento térmico presentó la Odds Ratio ajustada más alta (ORa = 20,40; IC95%:7,52-55,30 y fue positivo a Salmonella enterica serotipo enteritidis. Conclusiones: Existe evidencia epidemiológica y de laboratorio de que el biscuit glacé fue el alimento contaminado que causó el brote. La investigación destacó como factores contribuyentes la utilización de huevo crudo, la producción en grandes cantidades y con antelación al consumo del alimento.

  15. Brote por pseudomonas aeruginosa, en el área de atención ambulatoria de heridas quirúrgicas, en pacientes posmastectomizadas

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    Vilar-Compte Diana

    2003-01-01

    Full Text Available OBJETIVO: Describir un brote por Pseudomonas aeruginosa, en el área de atención ambulatoria de herida quirúrgica, en pacientes posmastectomizadas. MATERIAL Y MÉTODOS: Entre el 13 de marzo y el 18 de mayo de 2000 se definió como caso a las pacientes del Instituto Nacional de Cancerología de la Ciudad de México, mastectomizadas con infección quirúrgica por P aeruginosa resistente a ciprofloxacina y gentamicina. Se tomaron cultivos de los antisépticos, del material de curaciones, del agua y del personal de salud. Se efectuó un análisis de casos y controles. RESULTADOS: Se identificaron 13 infecciones tardías del sitio quirúrgico por P aeruginosa. La Pseudomona se aisló de las narinas de la enfermera y de las gasas que ella misma colocaba sobre la mesa de mayo, pero no de los paquetes de gasas cerrados del área de curaciones ambulatoria de tumores mamarios. El 14 de abril de 2000 se transfirió a la enfermera a otra área y se instauraron medidas estrictas para el control de infecciones. Después de esta fecha se diagnosticaron cuatro casos más. La radioterapia fue el único factor de riesgo asociado con la infección (RM=5.1, IC 95%=1.1-28.4. CONCLUSIONES: El brote probablemente estuvo causado en un inicio por una fuente común y se extendió por infección cruzada entre las pacientes. Las prácticas deficientes detectadas en el manejo de heridas y drenajes condujo a instaurar medidas preventivas específicas.

  16. Brote de dermatofilosis en terneros

    OpenAIRE

    2009-01-01

    La Dermatofilosis es una enfermedad aguda o crónica de la epidermis, caracterizada por lesiones inflamatorias, exudativas, sangrantes con formación de costras, causada por una bacteria, Dermathophilus congolensis. Afecta a bovinos, ovinos, equinos, caprinos, animales salvajes y al hombre considerandose una zoonosis menor. El presente trabajo comunica un brote causado por Dermathophilus congolensis en terneros de tambo. Los animales afectados presentaban lesiones en piel, no pruriginosas, esta...

  17. Investigación de vectores y reservorios en brote de Chagas agudo por posible transmisión oral en Aguachica, Cesar, Colombia

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    Hugo Soto

    2014-04-01

    Full Text Available Colombia tiene un registro de 11 casos de Chagas agudo y 80 casos por contaminación oral con Trypanosoma cruzi. Este trabajo analiza los hallazgos entomológicos y parasitológicos del brote de Aguachica, Cesar, en 2010. Un grupo interdisciplinario de profesionales de la salud y de universidades regionales realizó las pruebas de laboratorio a los pacientes y el estudio del foco de transmisión. Se detectaron 11 casos agudos de enfermedad de Chagas en una sola familia con vivienda sin triatominos domiciliados y, Rhodnius pallescens, Pantrongylus geniculatus, Eratyrus cuspidatus y dos Didelphis marsupialis infectados con T. cruzi en palmas de Attalea butyracea y Elaeis oleifera del área urbana de Aguachica. Se analiza la participación del R. pallescens y el rol de las palmas en el ciclo silvestre de T. cruzi y para la transmisión oral de la enfermedad de Chagas. Incursiones esporádicas de R. pallescens, P. geniculatus y E. cuspidatus silvestres desde palmas cercanas al domicilio humano pueden provocar brotes cada vez más frecuentes de Chagas oral.

  18. Brote de diarrea debido a intoxicación por alimentos en una empresa X. San José, Costa Rica, del 8 al 9 de julio 2003

    Directory of Open Access Journals (Sweden)

    Azálea Espinoza Aguirre

    2007-07-01

    Full Text Available El 9 de julio del 2003, se informó al Ministerio de Salud, la existencia de un brote de diarrea en una empresa X, en San José. Se investigó el brote, con el objetivo de verificar su magnitud, determinar factores de riesgo y mecanismo de transmisión, también recomendar medidas de prevención y control, a las autoridades de salud. Se revisaron 40 expedientes clínicos de pacientes atendidos por diarrea, en el consultorio de la empresa. Se definió como caso a todo funcionario, que presentó más de 2 deposiciones semilíquidas, y que consumió alimentos del comedor de la empresa, el 8 julio del 2003. Se tomaron coprocultivos, muestras de alimentos consumidos, y se enviaron a un laboratorio privado para el análisis. Se realizó un estudio de cohorte retrospectivo, y se aplicó un cuestionario. Se calcularon los riesgos relativos (RR, con intervalos de confianza del 95%, las tasas de ataque y porcentajes para los alimentos servidos. El 100% de los casos presentaron diarrea, sin fiebre. A los coprocultivos y a las muestras de alimentos, no se les buscó Clostridium perfringens. Las muestras de agua no reportaron contaminación fecal. El alimento sospechoso: cerdo con piña, presentó un RR=1,94;IC:95%(1,26-2,96. El período de incubación y la descripción de la enfermedad coincidieron con una intoxicación por Clostridium perfringens, por lo que, se asoció el brote al alimento sospechoso. Como en la empresa X se desconocían los procedimientos a seguir ante un brote de diarrea, causado por alimentos, se recomendó a los encargados de epidemiología del Área Rectora de Salud, capacitar en el abordaje de las intoxicaciones causadas por alimentos; a las empresas bajo su responsabilidad, que cuentan con establecimientos de alimentación.On July the 9th., 2003, an outbreak in company X was notified to the Ministry of Public Health in San José. This outbreak was investigated with the purposes of verifying its magnitude, determining risk

  19. Norovirus - hospital

    Science.gov (United States)

    Gastroenteritis - norovirus; Colitis - norovirus; Hospital acquired infection - norovirus ... are not treated with antibiotics because antibiotics kill bacteria, not viruses. Receiving plenty of extra fluids through ...

  20. Brote de gastroenteritis por agua potable de suministro público Waterborne outbreak of gastroenteritis transmitted through the public water supply

    Directory of Open Access Journals (Sweden)

    P. Godoy

    2003-06-01

    Full Text Available Introducción: La potabilidad del agua induce a descartar el posible origen hídrico de los brotes. El objetivo fue investigar un brote de gastroenteritis por agua potable de suministro público. Métodos: Después de la notificación de un brote de gastroenteritis en el municipio de Baqueira (Valle de Arán se diseñó un estudio epidemiológico de cohortes retrospectivo. Mediante un muestreo sistemático se eligió a 87 personas hospedadas en los hoteles y a 62 alojadas en diferentes apartamentos. Se recogió información sobre 4 factores (consumo de agua de la red, bocadillos, agua y alimentos en las pistas de esquí y presencia de síntomas. Se determinó la existencia de cloro, se analizó el agua de la red y se realizó un coprocultivo a 4 enfermos. La implicación de cada factor se determinó con el riesgo relativo (RR y su intervalo de confianza (IC del 95%. Resultados: La incidencia de gastroenteritis fue del 51,0% (76/149. Los porcentajes de los síntomas fueron los siguientes: fiebre, 27,0%; diarrea, 87,5%; náuseas, 50,7%; vómitos, 30,3%, y dolor abdominal, 80,0%. El único factor que presentó un riesgo estadísticamente significativo fue el consumo de agua de la red (RR = 11,0; IC del 95%, 1,6-74,7. La calificación sanitaria del agua fue de potabilidad. Se observó un defecto de situación del clorador en el depósito, que fue corregido. Se recomendó incrementar aún más las concentraciones de cloro, lo cual se acompañó de una disminución de los casos. Los coprocultivos de los 4 enfermos fueron negativos para las enterobacterias investigadas. Conclusiones: El estudio demuestra la posibilidad de presentación de brotes hídricos por agua cualificada como potable y sugiere la necesidad de mejorar la investigación microbiológica (determinación de protozoos y virus en este tipo de brotes.Introduction: The chlorination of public water supplies has led researchers to largely discard drinking water as a potential source of

  1. Infecciones concurrentes por dos serotipos del virus dengue durante un brote en el noroeste de Perú, 2008 Concurrent infections by two dengue virus serotypes during an outbreak in northwestern Peru, 2008

    OpenAIRE

    Enrique Mamani; Dana Figueroa; María Paquita García; María del Carmen Garaycochea; Pozo, Edwar J.

    2010-01-01

    Objetivo. Describir la existencia de infecciones concurrentes por diferentes serotipos del virus dengue (DENV) en un brote ocurrido en el noroeste de Perú durante el 2008. Materiales y métodos. Se analizó 73 muestras séricas de pacientes con dengue en un brote en el noroeste de Perú entre mayo y junio de 2008. Para la serotipificación del DENV se utilizó técnicas de biología molecular; así, primero se realizó la extracción del ARN con el kit QIAamp viral RNA Mini, luego se realizó la transcri...

  2. Brote por virus de la parotiditis G1 en la provincia de Almería en el año 2005

    OpenAIRE

    Pilar Barroso García; Ma Ángeles Lucerna Méndez; Amparo Navarro Monzón

    2007-01-01

    Fundamento:A pesar de que en España se registran coberturas elevadas de la vacuna de parotiditis siguen notificándose brotes epidémicos de parotiditis. El objetivo de este trabajo es describir un brote notificado en la provincia de Almería en el año 2005 y valorar la afectación en población vacunada. Métodos: Estudio descriptivo de los casos notificados. Variables estudiadas: Zona Básica de Salud, municipio, edad, sexo, tipo de población (autóctona y extranjera), fecha in...

  3. Brotes causados por Cronobacter Sakazakii

    OpenAIRE

    Sigüenza Andrés, Teresa

    2014-01-01

    Cronobacter sakazakii es un bacilo gram-negativo, no esporulado y móvil que pertenece a la familia Enterobacteriaceae. Puede ser considerado como un patógeno reciente pues el primer caso en el ser humano con el que se le relaciona consta de 1958. Además la información sobre él es reducida. Este microorganismo es ubicuo, es decir, se encuentra ampliamente distribuido en el ambiente. Se ha hallado especialmente en alimentos deshidratados como la leche en polvo, ya que puede vivir mucho tiemp...

  4. Brote de psitacosis en Granada

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    Ma Teresa León Espinosa de los Monteros

    2005-01-01

    Full Text Available Fundamento: La psitacosis se puede transmitir de pájaros infectados a seres humanos, siendo causa de neumonía atípica. El objetivo de este trabajo es determinar origen de un brote de psitacosis, las características de los sujetos expuestos, y describir las medidas para controlarlo. Métodos: Estudio descriptivo. Comunicación al Sistema de Vigilancia Epidemiológica y Delegación de Agricultura, realizándose las actuaciones pertinentes (inspección, toma de muestras, desinfección e inmovilización cautelar de aves, clausura del establecimiento; definición de caso y encuesta epidemiológica. Análisis de frecuencias. Resultados: 17 personas tuvieron contacto con animales sospechosos (53% varones/47% mujeres, de ellos 9 (edad media: 30 presentaron síntomas (100% fiebre, cuadro pseudogripal 44,4%. Se realizó serología para C. psitacci a 11 de los 17 sujetos expuestos (68,75%, resultando positiva en dos de ellos (18,18%. En el estudio de tejido pulmonar del fallecido se comprobó la presencia de DNA de C. psitacci. La confirmación diagnóstica entre personas sintomáticas fue del 33% (3/9. La Delegación de Agricultura impuso cuarentena a 22 núcleos zoológicos. De las 70 muestras tomadas (60: cloacas de animales y 10 aves, presentaron antígeno positivo 7 (10%, siendo la detección de ácidos nucleicos por PCR positiva en una de ellas. Conclusiones: La exposición a aves enfermas en los establecimientos implicados originó el brote, siendo el foco común de contagio de carácter laboral. La adecuada coordinación/colaboración entre las Delegaciones de Salud y Agricultura permitió evitar la aparición de casos nuevos.

  5. Infecciones concurrentes por dos serotipos del virus dengue durante un brote en el noroeste de Perú, 2008 Concurrent infections by two dengue virus serotypes during an outbreak in northwestern Peru, 2008

    Directory of Open Access Journals (Sweden)

    Enrique Mamani

    2010-03-01

    Full Text Available Objetivo. Describir la existencia de infecciones concurrentes por diferentes serotipos del virus dengue (DENV en un brote ocurrido en el noroeste de Perú durante el 2008. Materiales y métodos. Se analizó 73 muestras séricas de pacientes con dengue en un brote en el noroeste de Perú entre mayo y junio de 2008. Para la serotipificación del DENV se utilizó técnicas de biología molecular; así, primero se realizó la extracción del ARN con el kit QIAamp viral RNA Mini, luego se realizó la transcripción inversa y amplificación de los fragmentos de ADNc viral mediante las técnicas de reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR multiplex y de RT-Anidada PCR (RT-Nested PCR, y finalmente de realizó el secuenciamiento genético de los fragmentos de ADNc viral utilizando el kit Big Dye Terminator v.3,1. Resultados. Los 73 casos de dengue presentaron infecciones por diferentes serotipos: 34 (46,6% por DENV-3, 29 (39,7% por DENV-1, 4 (5,5% por DENV-4 y 6 casos (8,2% por DENV-1 y DENV-3. Las manifestaciones clínicas más frecuentes fueron fiebre y cefalea (100%, mialgia (94,5%, dolor ocular (83,6%, artralgia (78,1%, escalofríos (63,0%, nauseas/vómitos (38,4%, prueba de lazo positiva (30,1% y erupción cutánea (20,5%. Los pacientes con infecciones concurrentes presentaron cuadros leves, excepto una paciente que presentó prueba de lazo positivo y sangrado genital. Conclusión. Es el primer reporte de pacientes peruanos con infecciones concurrentes por dos serotipos del DENV sin formas graves de la enfermedad.Objetives. To establish the existence of concurrent infections by different dengue virus (DENV serotypes in an outbreak in the Northwestern in Peru during 2008. Material and methods. 73 serum samples from patients with dengue were analyzed during an outbreak that occurred in Northwestern in Peru between May and June 2008. Molecular biology techniques were used to serotype the DENV, thus, firstly the viral RNA

  6. Brote por Pseudomonas aeruginosa, en el área de atención ambulatoria de heridas quirúrgicas, en pacientes posmastectomizadas Outbreak of postmastectomy wound infections caused by Pseudomonas aeruginosa in an ambulatory surgical care setting

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    Diana Vilar-Compte

    2003-10-01

    Full Text Available OBJETIVO: Describir un brote por Pseudomonas aeruginosa, en el área de atención ambulatoria de herida quirúrgica, en pacientes posmastectomizadas. MATERIAL Y MÉTODOS: Entre el 13 de marzo y el 18 de mayo de 2000 se definió como caso a las pacientes del Instituto Nacional de Cancerología de la Ciudad de México, mastectomizadas con infección quirúrgica por P aeruginosa resistente a ciprofloxacina y gentamicina. Se tomaron cultivos de los antisépticos, del material de curaciones, del agua y del personal de salud. Se efectuó un análisis de casos y controles. RESULTADOS: Se identificaron 13 infecciones tardías del sitio quirúrgico por P aeruginosa. La Pseudomona se aisló de las narinas de la enfermera y de las gasas que ella misma colocaba sobre la mesa de mayo, pero no de los paquetes de gasas cerrados del área de curaciones ambulatoria de tumores mamarios. El 14 de abril de 2000 se transfirió a la enfermera a otra área y se instauraron medidas estrictas para el control de infecciones. Después de esta fecha se diagnosticaron cuatro casos más. La radioterapia fue el único factor de riesgo asociado con la infección (RM=5.1, IC 95%=1.1-28.4. CONCLUSIONES: El brote probablemente estuvo causado en un inicio por una fuente común y se extendió por infección cruzada entre las pacientes. Las prácticas deficientes detectadas en el manejo de heridas y drenajes condujo a instaurar medidas preventivas específicas.OBJECTIVE: To describe an outbreak due to Pseudomonas aeruginosa in postmastectomy wounds. MATERIAL AND METHODS: Cases were patients with a surgical infection caused by P. aeruginosa resistant to ciprofloxacin and gentamycin seen between March 13, 2000 and May 18, 2000, at Instituto Nacional de Cancerologia in Mexico City. Specimens for culturing were taken from faucets, antiseptics, and tap water, as well as from healthcare workers. A case-control analysis was conducted. RESULTS: Thirteen late surgical infections were caused

  7. Norovirus gastroenteritis.

    Science.gov (United States)

    Goodgame, Richard

    2007-03-01

    Recent epidemiologic studies have shown that norovirus is one of the most frequent causes of acute nonbacterial gastroenteritis. Reverse-transcription polymerase chain reaction and nucleotide sequencing are the means by which the hundreds of norovirus strains have been identified, named, and classified into genogroups and genetic clusters. They are also the means by which a particular strain is traced from the source of an outbreak throughout its spread. These molecular techniques have been combined with classic epidemiology to investigate norovirus outbreaks in diverse settings, including hospitals, nursing homes, dining locations, schools, daycare centers, and vacation venues. Outbreaks are difficult to control because of the apparent ease of transmission through food, water, person-to-person contact, and environmental surfaces. Almost all patients with norovirus gastroenteritis recover completely, but hospital and nursing home outbreaks have been associated with morbidity and mortality. The diagnostic and management approach to an individual patient is to use clinical and epidemiologic findings to rule out "not norovirus." At the first sign that there is an outbreak, strict compliance with cleaning, disinfection, and work release guidelines is important to prevent further spread.

  8. Brote epidémico de dermatitis por la oruga procesionaria del pino (Thaumetopoea pityocampa en escolares Outbreak of dermatitis caused by pine processionary caterpillar (Thaumetopoea pityocampa in schoolchildren

    Directory of Open Access Journals (Sweden)

    F. Artola-Bordás

    2008-12-01

    Full Text Available Fundamento. Describir un brote de dermatitis por exposición a las orugas procesionarias del pino (Thaumetopoea pityocampa ocurrido el 15 de marzo del 2006 en escolares, que realizaron una estancia vacacional en una masía rural a 2 Km de Villahermosa del Río (Castellón. Métodos. Se realizó un estudio epidemiológico transversal que incluyó a los setenta escolares, de 10 años de edad, y a 3 profesores procedentes de Castellón. Se empleó un cuestionario específico para ser cumplimentado por los escolares. Resultados. Seis casos de dermatitis (tasa de ataque 8,6%: 6/70 ocurrieron después del baño en la piscina climatizada de la masía al secarse con toallas, que habían dejado fuera del recinto de la piscina, y la Thaumetopoea pityocampa se deslizó sobre ellas. Los casos precisaron atención médica con administración de antihistamínicos, corticoides y duchas de agua fría. El riesgo de sufrir el cuadro por contacto con la Thaumetopoea pityocampa fue muy alto (Odds Ratio = 157,2; Intervalo de confianza del 95% 18,4-∞. Se recogieron Thaumetopoea pityocampa en las inmediaciones de la piscina y se observaron sus nidos en pinos próximos. Conclusiones. La presencia de Thaumetopoea pityocampa en zonas próximas a albergues rurales puede ser causa de brotes epidémicos y se requiere educación sanitaria de los escolares y eliminación de los nidos de Thaumetopoea pityocampa en las inmediaciones de estos albergues.Background. To describe a dermatitis outbreak caused by exposure to pine processionary caterpillar (Thaumetopoea pityocampa that took place on March 15th, 2006, in schoolchildren during their stay at a rural farm holiday centre in Villahermosa del Río (Castellón. Methods. A cross sectional epidemiological study was carried out on seventy schoolchildren, average age 10 years, and 3 teachers from Castellón. A specific questionnaire was used to be filled in by the schoolchildren. Results. Six cases of dermatitis (attack rate 8

  9. Determinación de factores de riesgo intrahospitalario en un brote por Pseudomonas aeruginosa en la sala de Ciren, Hospital Universitario del Valle, Cali, octubre de 1998.

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    María Eugenia González

    2009-10-01

    Full Text Available La sala de cuidado intensivo de recién nacidos es una de las áreas más críticas dentro de los hospitales porque alberga niños con muchos factores de riesgo para adquirir infecciones tales como bajo peso al nacer, inmunosupresión y exposición a procedimientos invasivos, determinando larga estancia hospitalaria. La frecuencia de patógenos en estas salas ha aumentado en las últimas décadas entre otras cosas como resultado de la supervivencia de niños con bajo peso al nacer. Las tasas de infección nosocomial varían de acuerdo con los informes presentados por las diferentes instituciones y ciudades. En EstadosUnidos aparece un rango de 5.9-30.4 de 100 pacientes egresados, en comparación con las tasas de México en dos hospitales pediátricos con unas tasas de 25% y 34%. En la sala de Cuidados Intensivos del Recién Nacidos del Hospital Universitario del Valle, Cali, la tasa era en 1994 de 12% y para 1995 aumentó a 15% por 100 egresos hospitalarios. Teniendo en cuenta la tasa de incidencia de densidad en donde se manejan los días de estancia en este hospital, ésta osciló entre 25 y 30 por mil días de estancia mensual para 1997 y 1998.

  10. Brote de influenza en Pucallpa, Ucayali, Perú. 2002

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    Julio Mayca P

    2003-10-01

    Full Text Available Comunicar un brote de influenza basado en la notificación de un probable brote de infección respiratoria en diciembre de 2002 por el Centro de Salud Nueva Requena (Pucallpa. Estudio transversal analítico que incluyó casos con fiebre no mayor de 72 horas, y por lo menos dos síntomas relacionados. Se tomó hisopado nasal-faríngeo, detectándose mediante inmunofluorescencia indirecta (IFI: influenza A, B, adenovirus, parainfluenza y virus sincicial respiratorio (VSR. Se recolectaron 14 muestras, reportándose principalmente fiebre (92,8%, rinorrea (92,8% y tos (42,8% Se encontró influenza B y parainfluenza 2 en 05 casos. Los diagnósticos encontrados coinciden con la literatura nacional. Es necesario implementar un sistema de vigilancia, descentralizando el diagnóstico laboratorial y las campañas educativas poblacionales.

  11. Caso clínico: Brote agudo de Psoriasis en un infectado por el VIH Clinical case: severe attack of psoriasis in an HIV infected patient

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    J.M. Sobrón

    2010-10-01

    Full Text Available La Psoriasis, que parece no tener una mayor prevalencia en infectados por el VIH, sí que presenta en su evolución en estos casos diferencias significativas ligadas no solo a la inmunodepresión, sino también a la propia acción del virus sobre los factores que influyen en la agudización de la psoriasis, como la estimulación de los queratinocitos, favorecer la presencia de infecciones en la piel, o la liberación de sustancia P que favorece igualmente el incremento queratinocítico. Se presenta un caso clínico y su expresión gráfica a través de las imágenes acompañantes.Psoriasis, which does not appear to have greater prevalence amongst HIV+ patients, does however present in its progress significant differences in these cases that are not only linked to immunodepression, but also to action of the virus itself on factors that aggravate psoriasis, such as the stimulation of keratinocytes, the favouring of skin infections, or the liberation of substance P, which also encourages growth in keratinocytes. A clinical case is presented along with explanatory imagess

  12. Brotes germinados y bacterias

    OpenAIRE

    García Olmedo, Francisco

    2011-01-01

    Ante la confusión y el revuelo asociados al último incidente causado por una cepa de la bacteria Escherichia coli (E. coli) en Alemania, tal vez no esté de más esta carta para recordar y actualizar escritos míos anteriores aparecidos en Revista de Libros sobre los riesgos alimentarios en general y sobre los peligros de dicho microorganismo en particular. 1 . Aunque es cierto que la proporción de cepas peligrosas de E. coli es quizás inferior a la de delincuentes entre los humanos, exi...

  13. Encefalitis por virus San Luis en la Ciudad de Buenos Aires durante el brote de dengue 2009 Saint Louis encephalitis virus in Buenos Aires city during the outbreak of dengue in 2009

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    Horacio López

    2011-06-01

    Full Text Available Se presenta un paciente de 80 años de edad, residente en la Ciudad de Buenos Aires, con diagnóstico serológico para el virus de la encefalitis de San Luis (SLE durante el brote de dengue ocurrido entre enero y mayo de 2009. Presentaba leucemia linfoide crónica en tratamiento con clorambucilo, cáncer de próstata tratado con hormonoterapia y radioterapia, e imágenes óseas compatibles con metástasis. El estudio del líquido cefalorraquídeo demostró pleocitosis con predominio de mononucleares y proteinorraquia elevada. El resultado de los cultivos para bacterias, hongos y micobacterias, así como el PCR en LCR para herpes virus, HSV, CMV y EBV, fue negativo. Se detectaron anticuerpos IgM para virus SLE tanto en LCR como en muestra de suero, con seroconversión IgG por neutralización en cultivos celulares y resultados negativos para los demás Flavivirus con circulación en Argentina. Se revisan evidencias sobre la presencia de virus de San Luis en nuestro país, y se señala la importancia de la confirmación diagnóstica y el estudio de otros Flavivirus en casos sospechosos de dengue con presentación grave o atípica. Este trabajo remarca la necesidad de fortalecer tanto la vigilancia epidemiológica del virus SLE, como el control vectorial para prevenir las diferentes infecciones transmitidas por mosquitos y conocer su efecto en Salud Pública en la Argentina.We report the case of a male, 80-year-old resident in the City of Buenos Aires, with a diagnosis of St. Louis encephalitis (SLE during a countrywide dengue outbreak, from January to May 2009. The patient had a chronic lymphocytic leukemia treated with chlorambucil, prostate cancer (hormone therapy and radiotherapy and images consistent with bone metastases. Cerebrospinal fluid examination showed pleocytosis with a predominance of mononuclear cells and high protein concentration. Bacteria, fungi and mycobacteria cultures, as well as the PCR for herpes virus, HSV, CMV and EBV, were

  14. Brote de gastroenteritis por el consumo de agua de suministro público causado por Shigella sonnei Waterborne outbreak of Shigella sonnei caused by consumption of public supply water

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    Pere Godoy

    2011-10-01

    Full Text Available Objetivos: Investigar un brote de gastroenteritis que afectó a la población de València d'Àneu (Lleida. Métodos: Estudio de cohortes sobre el consumo de agua de la red, de agua embotellada y de agua de manantiales. La cohorte se elaboró mediante contacto telefónico con todos los números privados del municipio. Se encuestó al 58,3% de la población censada (105/180 sobre diferentes consumos de agua, número de vasos consumidos diariamente y sintomatología. Se tomaron muestras de agua de la red municipal y de heces de diez enfermos. La implicación de cada agua consumida se estudió con el riesgo relativo (RR y su intervalo de confianza del 95% (IC95%. Resultados: La tasa de ataque global fue del 64,8% (68/105. La curva epidémica fue concordante con una exposición de 6 días. Resultó implicado el consumo de agua de suministro público (RR=4,2; IC95%: 1,5-11,9. Además, se constató una relación dosis-respuesta (χ²=34,1; p Objective: To investigate a waterborne outbreak in the population of València d'Àneu (Lleida, Spain. Methods: A cohort study of consumption of mains water, bottled water and spring water was carried out. The sample was obtained by telephone contact with all private numbers in the municipality. We surveyed 58.3% of the population census (105/180 for water consumption, number of glasses drunk daily and symptoms. The water supply in the municipal system was sampled, and the presence of Enterobacteriaceae in the stool samples of 10 patients was determined. The association of each type of water was studied with estimation of relative risks (RR and 95% confidence intervals (95% CI. Results: The overall attack rate was 64.8% (68/105. The epidemic curve was consistent with an exposure of 6 days. Consumption of public supply water was associated with gastroenteritis (RR=4.2, 95% CI: 1.5-11.9. In addition, a dose-response relationship was found (χ²=34.1; p <0.001. There was a higher risk of illness in consumers of 2

  15. Norovirus: Food Handlers

    Science.gov (United States)

    ... National Institutes of Health NoroCORE Food Virology For Food Workers Language: English Español (Spanish) Recommend on Facebook ... trabajadores del sector alimentario Norovirus and Working With Food CDC Vital Signs Report Preventing Norovirus Outbreaks, Food ...

  16. Advances in Norovirus Biology

    OpenAIRE

    Karst, Stephanie M.; Wobus, Christiane E.; Ian G Goodfellow; Green, Kim Y.; Virgin, Herbert W.

    2014-01-01

    Human noroviruses are a major cause of epidemic and sporadic gastroenteritis worldwide, and can chronically infect immunocompromised patients. Efforts to develop effective vaccines and antivirals have been hindered by the uncultivable nature and extreme genetic diversity of human noroviruses. Although they remain a particularly challenging pathogen to study, recent advances in norovirus animal models and in vitro cultivation systems have led to an increased understanding of norovirus molecula...

  17. Identificación de una nueva área de infección por Rickettsias del grupo typhi: estudio de un brote de tifus en Huánuco

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    Rosa Mostorino E

    2003-03-01

    Full Text Available Objetivos: Investigar un brote de síndrome febril en el distrito de Punchao mediante una evaluación clínica, laboratorial y entomológica para conocer los factores asociados a la aparición de dicho brote. Materiales y métodos: Debido al reporte de tres pacientes con cuadro clínico febril asociado a cefalea, mialgias y postración en la semana epidemiológica Nº41 del año 2000, procedentes del distrito de Punchao, Humalíes, Huánuco y ante la información de presentación inusual de pacientes febriles en la última semana en dicho lugar, se decidió investigar la naturaleza y características del brote. Se definió como caso a todo paciente con cuadro febril agudo y uno de estos síntomas: cefalea, mialgias o postración; procediéndose a la búsqueda activa de éstos y a la evaluación de presencia de anticuerpos para rickettsias en suero mediante inmunofluorescencia indirecta (IFI. Se capturaron roedores y se colectaron ectoparásitos en las viviendas (roedores, animales domésticos y humanos, a fin de identificar la presencia de Rickettsias en ellos mediante IFI, aislamiento o PCR. Resultados: No se logró el aislamiento del agente causal. Se evidenció circulación de la Rickettsia sp. (serología positiva tanto en humanos (en casos y en no casos como en roedores. Se evidenció mayor presencia de malos hábitos de aseo y condiciones inadecuadas de saneamiento básico en los casos (respecto a los no casos y una disminución de los casos luego del inicio de las medidas de control. Conclusiones: Las evidencias encontradas permitieron identificar un brote de tifus en Punchao, no pudiéndose determinar la especie involucrada debido a que no se aisló el agente causal.

  18. Brote de varicela en Herrera del Duque (Badajoz

    Directory of Open Access Journals (Sweden)

    Valadés F.J.

    2003-01-01

    Full Text Available Introducción: La varicela es una enfermedad de distribución mundial con una elevada morbilidad y pocas complicaciones, aunque puede presentar cuadros clínicos graves en inmunodeprimidos y adultos sanos. El objeto de este estudio es identificar y describir las características y los costes de un brote epidémico en Extremadura, cuya tasa anual de casos declarados al sistema de Enfermedades de Declaración Obligatoria (EDO oscila en alrededor de 5 por 1.000 habitantes. Métodos: Estudio descriptivo con búsqueda activa de casos entre los meses de noviembre del año 2000 y marzo de 2001, y de la susceptibilidad de la cohorte escolarizada del colegio de Herrera del Duque (Badajoz. Las definiciones de casos fueron recogidas de los protocolos de la Red de Vigilancia de la comunidad extremeña. La confirmación microbiológica se realizó por aislamiento del virus y por presencia de marcadores IgM e IgG en el suero del enfermo. Se analizaron los costes tangibles directos e indirectos y los no tangibles del brote. Resultados: De los 75 casos identificados, 71 (94,7% eran niños de entre uno y 9 años, predominando el sexo masculino. La tasa de ataque fue de 18,5 casos por 1.000 habitantes, y del 68,2% en convivientes menores de 10 años. La evolución fue benigna, sin ingresos hospitalarios ni complicaciones. Se encontró un 71,6% de niños susceptibles en los de entre 3 y 8 años. Se analizó una posible agregación temporal de casos en el colegio, obteniéndose un riesgo relativo (RR de 5,01 (p < 0,001. Se aisló el virus en las 4 muestras de vesículas estudiadas y la serología (IgM fue positiva en los 9 sueros estudiados. El coste total de brote fue de 927,21 e, con una media de 12,53 e por caso, y 205 días de pérdida escolar. Conclusión: Se confirmó la existencia de un brote de varicela en el colegio de la localidad de Herrera del Duque, con transmisión persona a persona, que afectó a niños de entre uno y 9 años. La elevada

  19. Cólera Neonatal: Reporte preliminar de un brote intrahospitalario

    OpenAIRE

    FELICES, Antonio; AVILA, Graciela; MUJICA, Oscar

    2013-01-01

    Se describe por primera vez en Perú, la ocurrencia de un brote intrahospitalario de cólera neonatal. Del 09 al 13 de febrero de 1992, se presentaron cuatro casos de diarrea en neonatos de un servicio de Recién Nacidos del Hospital Nacional Edgardo RebagliatiMartins (HNERM) del Instituto Peruano de Seguridad Social (IPSS), en quienes se aisló Vibrio cholerae 01 El Tor Ogawa. El estudio descriptivo permitió identificar al día 08 de febrero como período probable de exposición, compatible con un ...

  20. Brote nosocomial y comunitario de queratoconjuntivitis epidémica en Navarra

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    Salcedo Miqueleiz Asunción

    1997-01-01

    Full Text Available FUNDAMENTO: La queratoconjuntivitis epidémica (QCE es una infección aguda, generalmente bilateral, que se presenta de forma esporádica o en brotes a partir de una fuente de infección común, que puede ser una consulta de oftalmología o una piscina. La queratitis puede evolucionar hacia la formación de lesiones subepiteliales cornéales que pueden persistir durante varios meses. El objetivo de este trabaji fue la descripción de un brote de queratoconjuntivitis epidémica ocurrido en Navarra (España entre Abril y Agosto de 1996 que afectó al menos a 266 personas MÉTODOS: Descripción del brote, definición de caso clínico, investigación microbiológica, e investigación epidemiológica del brote mediante encuesta. RESULTADOS: En la investigación epidemiológica destaca la existencia de 2 consultas de oftalmología como mecanismo de transmisión de la enfermedad en 47 de los 116 pacientes investigados. La diseminación de la enfermedad en el entorno de los pacientes se pudo conocer en 119 casos, de éstos, 62 se consideraron casos secundarios. El diagnóstico etiológico del brote se realizó a los 11 días de iniciada la investigación microbiológica, aislándose adenovirus en muestras conjuntivales de 8 de los 19 pacientes investigados. CONCLUSIONES: Las medidas de prevención instauradas para el control del brote y la eficacia de las mismas se pone de manifiesto por la reducción paulatina de casos.

  1. Brote de shigellosis en un barrio de nivel social bajo

    Directory of Open Access Journals (Sweden)

    Chover Lara José Luis

    1999-01-01

    Full Text Available FUNDAMENTO: Los brotes epidémicos debidos a Shigella sonnei en nuestro entorno se hallan asociados frecuentemente a guarderías y colegios de educación primaria. Se comunica un brote epidémico de shigellosis en un barrio marginal. El objeto del estudio fue identificar la fuente de infección, modo de transmisión, características de los afectados y valorar la pertinencia de las medidas adoptadas. MÉTODOS: Para el seguimiento temporal del brote, se realizó un estudio observacional longitudinal mixto, en territorio delimitado para las variables clásicas de vigilancia epidemiológica (tiempo, lugar y persona. Se analiza la potencia infectante de la fuente (tasa de ataque por edad, sexo y centro escolar; razón de tasas y fracción atribuible. RESULTADOS: Temporalmente el brote se extendió entre las semanas 46/97 y la 8/98. Afectó a 218 personas (110 varones y 108 mujeres, que suponen el 5,46 % de la población del barrio. La mayor frecuencia se dio en el grupo de 0-4 años (43,6%, asisten a la guardería el 29,4% (tasa de ataque de 70,32% con un riesgo relativo de 3,9(IC 95%: 2,57-5,93 y fracción atribuible del 74,36%. La razón de tasas entre la guardería y los colegios del barrio es 5,62 (IC 95%: 4,33-7,31. Se realizó coprocultivo en muestras de 84 casos (38.5 % aislándose Shigella sonnei en 38 (17.4%. Se pautó tratamiento antibacteriano (amoxi-clavulánico y se aplicaron medidas higiénico-sanitarias individuales y colectivas. CONCLUSIONES: El largo periodo de transmisibilidad y la baja dosis de microorganismos viables necesarios para producir enfermedad, propició una transmisión interpersonal en los ámbitos escolar y familiar. Las medidas aplicadas limitaron de modo eficiente la transmisión del agente infeccioso en los centros escolares.

  2. Foodborne Norovirus Outbreaks

    Centers for Disease Control (CDC) Podcasts

    2012-09-17

    Dr. Aron Hall, a CDC epidemiologist specializing in noroviruses, discusses foodborne norovirus outbreaks.  Created: 9/17/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID); National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/17/2012.

  3. Outbreak of acute gastroenteritis in a rural population, spread person to person contact Brote de gastroenteritis aguda en una población rural por transmisión de persona a persona

    Directory of Open Access Journals (Sweden)

    Sonia Garrido Almagro

    2004-12-01

    ón logística.Resultados: No se observaron diferencias significativas en la variable sexo y de consumo de cualquier tipo de agua (red y embotellada. La curva epidémica no refleja un comienzo explosivo. En el cálculo de la OR ajustada destaca la relación causal los antecedentes familiares de padecer la enfermedad (OR ajustada= 5,32; IC-95% 1,23- 22,93; p=0,025. La inspección de la red de agua estaba bien y no se remitieron muestras de heces de enfermos para su análisis.Conclusiones: Se trata de un brote de gastroenteritis aguda de base poblacional, de etiología desconocida y con mecanismo de transmisión de persona a persona.

  4. Recent advances in understanding noroviruses

    Science.gov (United States)

    Bartnicki, Eric; Cunha, Juliana Bragazzi; Kolawole, Abimbola O.; Wobus, Christiane E.

    2017-01-01

    Noroviruses are the leading cause of acute gastroenteritis around the world. An individual living in the United States is estimated to develop norovirus infection five times in his or her lifetime. Despite this, there is currently no antiviral or vaccine to combat the infection, in large part because of the historical lack of cell culture and small animal models. However, the last few years of norovirus research were marked by a number of ground-breaking advances that have overcome technical barriers and uncovered novel aspects of norovirus biology. Foremost among them was the development of two different in vitro culture systems for human noroviruses. Underappreciated was the notion that noroviruses infect cells of the immune system as well as epithelial cells within the gastrointestinal tract and that human norovirus infection of enterocytes requires or is promoted by the presence of bile acids. Furthermore, two proteinaceous receptors are now recognized for murine norovirus, marking the first discovery of a functional receptor for any norovirus. Recent work further points to a role for certain bacteria, including those found in the gut microbiome, as potential modulators of norovirus infection in the host, emphasizing the importance of interactions with organisms from other kingdoms of life for viral pathogenesis. Lastly, we will highlight the adaptation of drop-based microfluidics to norovirus research, as this technology has the potential to reveal novel insights into virus evolution. This review aims to summarize these new findings while also including possible future directions. PMID:28163914

  5. Norovirus: U.S. Trends and Outbreaks

    Science.gov (United States)

    ... from contaminated water and raspberries irrigated with contaminated water have caused norovirus outbreaks. Norovirus on Cruise Ships Over 90% of diarrheal disease outbreaks on cruise ships are caused by norovirus ( ...

  6. Brote con síntomas respiratorios en la provincia de Almería por una posible exposición a microalgas tóxicas An epidemic outbreak with respiratory symptoms in the province of Almeria (Spain due to toxic microalgae exposure

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    Pilar Barroso García

    2008-12-01

    Full Text Available Objetivos: Describir un brote con clínica de irritación de las vías respiratorias, notificado en una localidad de la costa almeriense en agosto de 2006, así como la investigación etiológica realizada. Métodos: Estudio descriptivo y de casos y controles. Se dividió la localidad en 3 zonas según su mayor o menor cercanía al mar (de 1 a 3. La sintomatología fue valorada subjetivamente de menor a mayor gravedad (1 a 3. Se estimaron las tasas de ataque (TA. Para relacionar la gravedad de los síntomas por zonas y el tipo de exposición se calcularon las odds ratio (OR y sus intervalos de confianza del 95% (IC95%. También se utilizó la prueba de la χ2 y el test exacto de Fisher. Se realizó una investigación ambiental. Resultados: Se encuestó a 57 casos y 26 controles. Se estimó una TA del 69%. El síntoma más frecuente fue el estornudo (87,7%. Los individuos de la zona 1 presentaron mayor riesgo de padecer sintomatología de más gravedad que los de la zona 3 (OR = 46,7; IC95%: 4,7-2.067,4. Los que indicaron una mayor permanencia fuera de la vivienda tuvieron mayor riesgo de enfermar (OR = 12,2; IC95%: 1,1-615,1. En agua de mar se detectaron 1.200 células/l de dinoflagelados Ostreopsis. Conclusiones: Se trata de un brote con sintomatología respiratoria, con distinto grado de afectación según la cercanía al mar de la vivienda. Según la investigación epidemiológica y ambiental, lo más probable es que se haya debido a la presencia de microalgas tóxicas Ostreopsis.Aim: To describe an outbreak with symptoms of respiratory tract irritation reported in a village located on the Almerian coast in August 2006, as well as the etiological research performed. Methods: We performed a descriptive case-control study. The village was divided into three areas (from 1 to 3 according to the distance from the sea. Symptomatology was subjectively assessed on an ascending severity scale (from 1 to 3. Attack rates (AR were estimated. To correlate

  7. Brote de síndrome de Shock tóxico estreptocócico en una guardería de Cantabria en 2006

    OpenAIRE

    Manuel Ortega-Mendi; Luís Martínez-Martínez; Alvaro González de Aledo-Linos; Jesús Agüero-Balbín; Luís Viloria-Raymundo; Ma. Eliecer Cano-García; Jorge Calvo-Montes; Purificación Mellado-Encinas; Amparo Fernández-Rodríguez

    2008-01-01

    Fundamento: Las infecciones por estreptococo betahemolítico grupo A (EGA) sólo excepcionalmente son agresivas y con letalidad alta. Más infrecuente aún es la ocurrencia de un brote. El objetivo de este estudio es la descrpción de un brote epidémico por estreptococo beta-hemolítico grupo A en una guardería de Cantabria. Métodos: Estudio descriptivo de un brote de síndrome de shock tóxico estreptocócico (3 casos, uno letal) en una guardería, que motivó una intervención d...

  8. LA BRUCELOSIS COMO ENFERMEDAD PROFESIONAL: ESTUDIO DE UN BROTE DE TRANSMISION AEREA EN UN MATADERO

    Directory of Open Access Journals (Sweden)

    Ma. Elena Rodríguez Valín

    2001-01-01

    Full Text Available Fundamento: La aparición de un número elevado de casos de brucelosis entre los trabajadores de un matadero en Zaragoza, en el que se sacrificaba ganado ovino procedente de las campañas de saneamiento ganadero, hizo iniciar una investigación para esclarecer el origen del brote. Métodos: El estudio se estructuró en tres partes: 1 Descripción del brote; 2 Estudio de la estructura y actividad del matadero en cuanto al número de animales sacrificados, carga de trabajo del personal y riesgo por zona de trabajo y 3 Estudio de casos y controles no apareado. Resultados: No hubo diferencias significativas entre las tasas de ataque por secciones de trabajo. El análisis del sacrificio reveló una variación concomitante entre las curvas de sacrificio de ovino de saneamiento y la epidémica. El estudio de casos y controles no reveló diferencias significativas para los siguientes factores de riesgo: trabajo en zona de riesgo, uso de medidas de protección y realización de cortes y heridas. Conclusiones: El brote está relacionado con el sacrificio de ovino de saneamiento. El que no se observaran diferencias significativas por secciones o por trabajar en la zona de riesgo es compatible con una exposición generalizada. Tampoco se observaron diferencias entre los trabajadores respecto a la realización de cortes y heridas o el uso de medidas de protección, lo que da importancia a la transmisión aérea.

  9. La brucelosis como enfermedad profesional: estudio de un brote de transmision aerea en un matadero

    Directory of Open Access Journals (Sweden)

    Rodríguez Valín Mª Elena

    2001-01-01

    Full Text Available FUNDAMENTO: La aparición de un número elevado de casos de brucelosis entre los trabajadores de un matadero en Zaragoza, en el que se sacrificaba ganado ovino procedente de las campañas de saneamiento ganadero, hizo iniciar una investigación para esclarecer el origen del brote. MÉTODOS: El estudio se estructuró en tres partes: 1 Descripción del brote; 2 Estudio de la estructura y actividad del matadero en cuanto al número de animales sacrificados, carga de trabajo del personal y riesgo por zona de trabajo y 3 Estudio de casos y controles no apareado. RESULTADOS: No hubo diferencias significativas entre las tasas de ataque por secciones de trabajo. El análisis del sacrificio reveló una variación concomitante entre las curvas de sacrificio de ovino de saneamiento y la epidémica. El estudio de casos y controles no reveló diferencias significativas para los siguientes factores de riesgo: trabajo en zona de riesgo, uso de medidas de protección y realización de cortes y heridas. CONCLUSIONES: El brote está relacionado con el sacrificio de ovino de saneamiento. El que no se observaran diferencias significativas por secciones o por trabajar en la zona de riesgo es compatible con una exposición generalizada. Tampoco se observaron diferencias entre los trabajadores respecto a la realización de cortes y heridas o el uso de medidas de protección, lo que da importancia a la transmisión aérea.

  10. Norovirus in the United States

    Centers for Disease Control (CDC) Podcasts

    2013-09-09

    Dr. Aron Hall, a CDC epidemiologist specializing in norovirus, discusses the impact of norovirus in the United States.  Created: 9/9/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 9/17/2013.

  11. BROTES EPIDÉMICOS DE SARAMPIÓN EN ANDALUCÍA DURANTE EL PERÍODO 2010-2015

    Directory of Open Access Journals (Sweden)

    Carmen Montaño Remacha

    2015-01-01

    Full Text Available El Sistema de Vigilancia Epidemiológica de Andalucía (SVEA es el encargado de vigilar e investigar urgentemente cualquier notificación de sospecha de sarampión y otras enfermedades de declaración obligatoria y alertas. El objetivo del artículo es describir las características epidemiológi-cas de los brotes de sarampión ocurridos en Andalucía en los últimos cinco años (2010-2015 así como las medidas de actuación llevadas a cabo durante los mismos. En el periodo estudiado se notificaron tres brotes. El primero de ellos comenzó en Granada en 2010 en población contraria a la vacunación. Las medidas de control adoptadas fueron las recogidas en el protocolo de sarampión del SVEA (aislamiento de casos, identificación e inmunización de contactos, entre las que se incluyeron acciones judiciales ante la negativa de un determinado colectivo a vacunar a sus hijos. El segundo brote comen-zó en Sevilla en 2011 en una de las zonas denominadas “con necesidades de transformación social” y se extendió por toda la provincia. A partir de aquel brote se introdujo de forma rutinaria la revisión de las coberturas vacunales dentro del sistema de vigilancia, identificando a los grupos más vulnerables. Durante el primer semestre de 2015 ha habido un pequeño brote en Granada con 15 casos. Se controló rápidamente debido a la actuación precoz en la mayoría de los casos, a la instauración de las medidas correspondientes en centros sanitarios y escolares y a la alta cobertura vacunal de la población.

  12. Brote de fiebre amarilla en comunidad aguaruna en la provincia de Bagua, DIRESA Amazonas. Diciembre 2005

    OpenAIRE

    Clendenes Alvarado, Orlando Martín; Pachas Chávez, Paul; Quezada Tirado, Héctor Eduardo; Arévalo Daza, Luis; Purisaca Morante, Enrique; Díaz Díaz, Artidoro; Espinoza Silva, Máximo Manuel

    2006-01-01

    El 26 de diciembre de 2006, el Ministerio de Salud toma conocimiento de un brote de una enfermedad caracterizada como un síndrome febril hemorrágico, en la localidad de Alto Tuntus de la etnia Aguaruna, en la provincia de Bagua. Esta localidad se encuentra a siete días de camino por trocha. El acceso más rápido es a través de helicóptero. Hasta el 28 de diciembre se tenía conocimiento oficial de 73 casos identificados y siete fallecidos, en una comunidad de aproximadamente 425 habitantes....

  13. Brote de criptosporidiosis en Guadarrama (Comunidad Autónoma de Madrid

    Directory of Open Access Journals (Sweden)

    Rodríguez-Salinas Pérez Enrique

    2000-01-01

    Full Text Available Fundamento: En la primavera de 1998 hubo un brote de gastroenteritis aguda en Guadarrama (Comunidad de Madrid, España que afectó sobre todo a niños en edad preescolar. Métodos: Se hizo un estudio descriptivo y analítico (casos y controles del brote. Se tomaron muestras para estudio microbiológico de las heces de los afectados. Se inspeccionó el sistema de captación de agua de consumo de propiedad municipal y se tomaron muestras para análisis microbiológico. Resultados: Veintiún niños/as de 0 a 5 años presentaron diarrea líquida de más de 5 días de duración. Se encontró una asociación estadísticamente significativa entre el consumo de agua del grifo y la gastroenteritis [OR=5,73 (1,18-43,30; p<0,05]. No se halló asociación con otras variables investigadas. Se detectaron ooquistes de Cryptosporidium parvum en heces de ocho de las personas afectadas. Se observaron deficiencias en el sistema de captación y depuración de agua de consumo público de propiedad municipal pero no se encontraron ooquistes en los análisis del agua. Conclusiones: Los resultados de la investigación epidemiológica sustentan que el origen del brote de gastroenteritis por Cryptosporidium parvum fue el agua del grifo. Aunque no se detectó este parásito en los análisis de agua, esto es explicable por las dificultades que entraña esta técnica. En la revisión bibliográfica, no se han hallado descripciones de brotes epidémicos similares en nuestro país, pero según algunos informes, no son infrecuentes en países de nuestro entorno. Por tanto, Cryptosporidium parvum debería ser tenido en cuenta en el diagnóstico y manejo de estas situaciones.

  14. Human Noroviruses and Sporadic Gastroenteritis

    Centers for Disease Control (CDC) Podcasts

    2008-08-05

    In this podcast, Dan Rutz speaks with Dr. Manish Patel, a medical officer with the Division of Viral Diseases at CDC, about an article in August 2008 issue of Emerging Infectious Diseases reporting on nororviruses. Dr. Patel reviewed 235 studies and identified 31 original studies about noroviruses. Norovirus is the leading cause of epidemic gastroenteritis.  Created: 8/5/2008 by Emerging Infectious Diseases.   Date Released: 7/30/2008.

  15. Agentes bacterianos asociados a brotes de Enfermedades Trasmitidas por Alimentos (ETA) en Camagüey, Cuba, durante el período 2000-2008 - Bacterial agents associated to foodborne outbreaks in Camagüey, Cuba, in the period 2000-2008

    OpenAIRE

    Rodríguez Torrens, Herlinda; Barreto Argilagos, Guillermo; Sedrés Cabrera, Martha

    2010-01-01

    ResumenPara establecer la incidencia de los agentes bacterianos en los brotes de ETA en la ciudad de Camagüey, se procesó la información recogida en la Sección de Microbiología Sanitaria del Centro Provincial de Higiene, Epidemiología y Microbiología correspondiente al período 2000-2008.SummaryIn order to establish the incidence of bacterial agents related with foodborne outbreaks occurred in the city of Camagüey, was processed all the information located at the Sanitary Microbiology Section ...

  16. PLAN DE VIGILANCIA DE BROTES EPIDÉMICOS RECIENTES DE SARAMPIÓN Y RUBEOLA EN CATALUÑA

    Directory of Open Access Journals (Sweden)

    Mireia Jané

    2015-01-01

    Full Text Available El sarampión y la rubeola son dos enfermedades inmunoprevenibles. En Cataluña, desde 1988, se administra a todos los niños y niñas dos dosis de vacuna antirubeola y antisarampión con altas coberturas vacunales. Desde 1990 se lleva a cabo el Programa de eliminación del sarampión en Cataluña que contempla alcanzar y mantener un nivel elevado de inmunidad en la po-blación mediante coberturas vacunales altas, una vigilancia epidemiológica intensa y una respuesta inmediata ante la aparición de un caso o un brote. La tasa de sarampión se situó en 2014 en 1,9 casos/100.000 habitantes, des-tacando los brotes recientes de 2006, 2011, 2013 y 2014, que afectaron a 381, 289, 31 y 124 personas respectivamente. Todos los brotes fueron des-encadenados por un caso importado. En el 2011 y 2014 el 6% y 5,5% de los afectados fueron profesionales de la salud. En todos los brotes se observó una amplia variedad genotípica. En el caso del Programa de eliminación de la rubeola, desde el 2002 ha habido 68 casos confirmados de rubeola post-natal y 5 casos de rubeola congénita confirmada. En la vigilancia y control del sarampión y la rubeola, además de reforzar las coberturas vacunales, es esencial la declaración urgente, antes de las 24 horas, de la sospecha y la confirmación por parte del laboratorio de los casos declarados. Respecto a las coberturas vacunales, destaca la necesidad de reforzar la vacunación en el grupo de profesionales de la salud al igual que en otros colectivos no vacunados. En este sentido se aconseja vacunar a todas las personas nacidas después de 1966 que no estén correctamente vacunadas con dos dosis de triple vírica. Asimismo es de destacar que el avance en el estudio de los genotipos aislados permite identificar diversas importaciones procedentes de otros países europeos con brotes activos, aspecto que facilita la vigilancia de estas enfermedades.

  17. El papel del agua para consumo humano en los brotes de diarrea reportados en el período 1999 - 2001 en Costa Rica

    Directory of Open Access Journals (Sweden)

    Carmen Valiente

    2002-07-01

    Full Text Available El presente estudio recopila los resultados de veintidos brotes de diarrea reportados en Costa Rica, durante el período comprendido entre marzo 1999 y marzo del 2001, con el objetivo de evaluar el papel del agua para consumo humano como canal de transmisión de los potenciales agentes causantes; para lograrlo se estableció un "Sistema Cualitativo de Valoración del Grado de Importancia del Agua para Consumo Humano en la Transmisión de las Diarreas". Los resultados indican que cinco brotes (22.7% se clasifican en la categoría 1, es decir, el agua tuvo un 100% de responsabilidad en la transmisión del agente etiológico; ya que este se aisló tanto en las heces de los pacientes como en el agua para consumo de las poblaciones respectivas. Dos brotes se ubicaron en la categoría 11 (9.1 %; en este caso, aunque se aislaron los mismos géneros bacterianos en las heces y el agua, diferían en la especie o en alguna otra característica. En diez brotes no se logró aislar el agente patógeno en el agua de consumo (45.0%; sin embargo, las poblaciones afectadas utilizaban agua de calidad no potable, por eso se sitúan en la categoría III. En la categoría IV se clasificó solo un brote (4.5%, ya que no se pudo comprobar la presencia del agente patógeno en el agua de consumo y esta no presentaba contaminación fecal (catalogada como potable, pero se aislaron bacterias patógenas oportunistas en las fuentes de abastecimiento. En la categoría V se ubican cuatro brotes (18.2%, pues las poblaciones afectadas usaban agua potable pero no se logró aislar ningún patógeno oportunista en el preciado líquido. Otro aporte de este trabajo es que demuestra que la mayoría de los brotes de diarrea se presentan en la época de verano, principalmente en los meses de febrero y marzo. Además, en el 36.0% de los brotes se aisló la bacteria Shigella (flexneri y sonnei, seguida por Aeromonas (hydrophila y caviae en el 14%. En uno de los brotes se aisló Salmonella

  18. ANÁLISIS DE UN BROTE DE SARAMPIÓN EN UNA BARRIADA DE LA PROVINCIA DE SEVILLA, ESPAÑA

    Directory of Open Access Journals (Sweden)

    Antonio Luna Sánchez

    2013-01-01

    Full Text Available Fundamentos: En 2011 en Sevilla (España un brote de Sarampión afec- tó a 1.759 personas. Comenzó en la Barriada de Santa Isabel, San Juan de Az- nalfarache (Sevilla, donde reside una comunidad Romaní. El objetivo del trabajo es describir epidemiologicamente el brote en la localidad y calcular el riesgo de enfermar por sarampión de los residentes en la barriada Santa Isa- bel. Método: Se diseñó un estudio de cohortes retrospectivo. Se consideró población expuesta a los residentes en la barriada de Santa Isabel y no ex- puesta a la del resto del municipio. Las fuentes de datos fueron: el Instituto de Estadística de Andalucía, el Ayuntamiento del municipio y el Sistema de Vi- gilancia Epidemiológica de Andalucía. Se describió el brote y se calcularon incidencias y el Riesgo Relativo. Los casos fueron confirmados por criterios clínicos, de laboratorio y/o epidemiológicos. Resultados: En la barriada los casos se concentraron entre el colectivo etario de entre 2 y 19 años, mientras que en el resto de la localidad se produ- jo en menores de 2 y mayores de 19 años. La incidencia global del brote fue de 0,98 por 1.000 habitantes. En San Juan de 4,94 . Entre los expuestos fue de 23,15 y de 2,1 en los no expuestos. En el colectivo de 2 a 19 años la inciden- cia fue 89,58 por 1.000 habitantes en la Barriada y de 5,33 por 1.000 habitan- tes en el resto de la localidad. Conclusiones: El brote afectó en mayor medida a menores de 20 años, a población no vacunada y residente en la Barriada Santa Isabel. El riesgo de enfermar de Sarampión en la Barriada fue de 11 y de 17 en el colectivo entre 2 y 19 años. Precisamos elaborar estrategias que reduzcan las desigualdades en salud que acompañan a algunos brotes epidémicos.

  19. Agentes bacterianos asociados a brotes de Enfermedades Trasmitidas por Alimentos (ETA en Camagüey, Cuba, durante el período 2000-2008 - Bacterial agents associated to foodborne outbreaks in Camagüey, Cuba, in the period 2000-2008

    Directory of Open Access Journals (Sweden)

    Rodríguez Torrens, Herlinda

    2010-02-01

    Full Text Available ResumenPara establecer la incidencia de los agentes bacterianos en los brotes de ETA en la ciudad de Camagüey, se procesó la información recogida en la Sección de Microbiología Sanitaria del Centro Provincial de Higiene, Epidemiología y Microbiología correspondiente al período 2000-2008.SummaryIn order to establish the incidence of bacterial agents related with foodborne outbreaks occurred in the city of Camagüey, was processed all the information located at the Sanitary Microbiology Section submitted to the Provincial Center of Hygiene, Epidemiology and Microbiology, corresponding to the period 2000-2008.

  20. Enraizamiento de brotes de capirona Calycophyllum spruceanum (Benth.) Hook. f. ex Schum., en la amazonía peruana.

    OpenAIRE

    Vallejos-Torres, Geomar; Instituto de Investigaciones de la Amazonía Peruana; Gonzales-Polar, Luis Enrique Toledo; Reforesta Perú S.A.C.; Arévalo-López, Luis Alberto; Instituto de Investigaciones de la Amazonía Peruana

    2014-01-01

    En la ciencia del mejoramiento genético no existe una metodología para la propagación asexual por enraizamiento de estacas de Calycophyllum spruceanuma escala comercial. A continuación se presenta una metodología del proceso de enraizamiento para la producción de plantones clonales a escala comercialde C. spruceanum. El objetivo del estudio fue evaluar el enraizamiento de brotes, bajo el efecto del número de hojas (una y dos) y tres dosis de ácido indol-3-butírico (2000, 3000 y 4000 ppm) util...

  1. De flores, brotes y palmitos: alimentos olvidados

    OpenAIRE

    2008-01-01

    Muchos de los alimentos que aprovecharon nuestros antepasados fueron relegados a alimentos subexplotados por los procesos de conquista o por la desaparición de sus hábitats naturales. Este trabajo exploró las razones de este cambio y el potencial nutricional, agronómico y comercial de un grupo de estos alimentos: las hortalizas subexplotadas. Se realizó a partir de fuentes documentales y entrevistas a personas, generalmente adultos mayores, de diferentes partes del país durante el 2003 y el 2...

  2. Norovirus transmission on cruise ship.

    Science.gov (United States)

    Isakbaeva, Elmira T; Widdowson, Marc-Alain; Beard, R Suzanne; Bulens, Sandra N; Mullins, James; Monroe, Stephan S; Bresee, Joseph; Sassano, Patricia; Cramer, Elaine H; Glass, Roger I

    2005-01-01

    An outbreak of norovirus gastroenteritis affected passengers on two consecutive cruises of ship X and continued on 4 subsequent cruises despite a 1-week sanitization. We documented transmission by food and person-to-person contact; persistence of virus despite sanitization onboard, including introductions of new strains; and seeding of an outbreak on land.

  3. BROTE DE LEGIONELOSIS EN UN RESTAURANTE DE LA COMUNIDAD DE MADRID

    Directory of Open Access Journals (Sweden)

    Isabel Abad Sanz

    2014-01-01

    Full Text Available Fundamentos: el 27 de Junio de 2012 se detectó en el Servicio de Salud Pública del Área 8 de la Comunidad de Madrid un brote de legio- nelosis con 46 personas afectadas. Todas habían estado en el mismo restaurante del municipio de Móstoles dentro del periodo de incubación de la enfermedad. El objetivo de este trabajo es describir la evolución del brote y las medidas sanitarias adoptadas durante el mismo. Métodos: se trata de un estudio descriptivo. Se estudiaron las variables demográficas de los enfermos , antecedentes patológicos, síntomas, evolución clínica y pruebas diagnósticas. Para las variables cualitativas se calcularon frecuencias y porcentajes. Para las variables cuantitativas la media, el valor mínimo y máximo. En las muestras de agua tomadas en las instalaciones de riesgo se estudió concentración de cloro, pH, temperatura y presencia de Legionella. Resultados: en el cultivo del agua del filtro de arena de la depuradora de la fuente exterior creció Legionella pneumophila Serogrupo 1, Sub-grupo Pontiac Allentown/France. Este resultado coincidió con la cepa aislada en las muestras respiratorias de 4 pacientes. Por otro lado, en las muestras de biopelícula obtenidas en la champanera se detectó por PCR la presencia de Legionella pneumophila cuya secuenciación de genes fue idéntica a la encontrada en la muestra respiratoria de un paciente. Conclusiones: se consiguió aislar Legionella pneumophila serogrupo 1 Subgrupo Pontiac Allentown/France serotipo 448 en muestras ambientales, coincidente con la Legionella aislada en muestras respiratorias de algunos pacientes, por lo que se pudo demostrar la vinculación entre el factor de riesgo ambiental y la enfermedad. Este vínculo se confirmó además por secuenciación genética realizada por PCR.

  4. Preventing Norovirus Outbreaks PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2014-06-03

    This 60 second public service announcement is based on the June 2014 CDC Vital Signs report. Norovirus infects about 20 million Americans each year. Learn how to protect yourself and your family from this very contagious, potentially serious illness.  Created: 6/3/2014 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 6/3/2014.

  5. Brotes de leptospirosis humana en la provincia de Ciego de Ávila, Cuba Human leptospirosis outbreak in the district of Ciego de Ávila, Cuba

    Directory of Open Access Journals (Sweden)

    Miguel Suárez Hernández

    1999-02-01

    Full Text Available Se analizan los brotes de leptospirosis ocurridos en la provincia de Ciego de Ávila en el periodo de 1980 a 1995. En la etapa se notifican 40 brotes. Las actividades principales vinculadas a los mismos fueron la atención al cultivo de la caña de azúcar, al cultivo del plátano, el baño en río y las inundaciones. Se nota un incremento de brotes a partir del mes de junio. En los meses de octubre y noviembre se reportan las mayores incidencias. Los grupos de edades que más casos aportaron fueron de 10-14 años, 15-19 años y 30-34 años. El sexo más afectado fue el masculino. Los grupos más afectados fueron los estudiantes, pobladores urbanos y trabajadores agrícolas cañeros. De los 40 brotes, 21 fueron confirmados por medio de la prueba de microaglutinación y 19 por la prueba hemolitica, siendo los serogrupos más frecuentes Pomona y Australis.Forty leptospirosis outbreaks occurred in Ciego de Avila province from 1980 to 1995. The main events involved in the outbreaks were floods, bathing in rivers and activities related to sugar cane and banana cultivation. The number of cases increased after June, with higher incidences reported in October and November. The most affected age groups were 10-14 years, 15-19 years and 30-34 years. Men were more affected than women. Students, people residing in the urban zone and farmers were the most affected groups. A total of 21 outbreaks out of 40 were confirmed by the microagglutination test and the remaining 19 by the hemolytic test. Pomona and Australis were the serogroups most frequently detected by microagglutination.

  6. Brote de encefalitis de San Luis en el Área Metropolitana Buenos Aires

    Directory of Open Access Journals (Sweden)

    Alfredo Seijo

    2011-06-01

    Full Text Available Se describen los hallazgos epidemiológicos y clínicos de 13 enfermos con diagnóstico de infección por virus de la encefalitis de San Luis, con transmisión entre enero y marzo de 2010, en el Area Metropolitana Buenos Aires (AMBA. Los 13 enfermos, promedio de edad 38 años, tuvieron un comienzo agudo caracterizado por hipertermia y cefalea. Entre los días dos y diez de iniciados los síntomas, 7/13 enfermos tuvieron signos y síntomas de compromiso neurológico caracterizado por meningitis sin signos encefálicos en 1/7. En 6/7 los hallazgos más frecuentes fueron: rigidez de nuca, desorientación temporoespacial, fotofobia, confusión y alteración del lenguaje. Dos resonancias magnéticas y un electroencefalograma presentaron signos de afectación de lóbulos temporales. El líquido cefalorraquídeo se caracterizó por pleocitosis con predominio de células mononucleadas, glucorraquia normal y discreto aumento de proteínas. No hubo casos fatales. En 6/13 pacientes la sospecha clínica inicial fue dengue. Por la agrupación espacial y temporal de los casos puede considerarse un brote epidémico, el primero conocido en el AMBA, ya que no se había notificado previamente la circulación epidémica del virus.

  7. Brote de fiebre amarilla selvática en Colombia 2004

    Directory of Open Access Journals (Sweden)

    Pilar Bernal M.

    2004-03-01

    Full Text Available

    Antecedentes: el 9 de enero se confirma un caso de fiebre amarilla en la sierra nevada de Santa Marta cuya circulación viral es la continuación de la presentada en el 2003 en la región del Catatumbo. En la región no se confirmaban casos desde el año 1979 y el comportamiento del brote es similar al presentado en dicho año.

    Metodología: estudio descriptivo longitudinal de casos captados mediante vigilancia activa comunitaria, estudio de casos y vigilancia pasiva. Los casos son confirmados por IgM, inmunohistoquímica y patología. Se realizaron acciones del fortalecimiento de la vigilancia de febriles icterohemorrágicos, entomológica, vectorial y de epizootias. Igualmente acciones de intensificación de la inmunización de susceptibles y educación a la comunidad.

    Resultados: se confirmó la circulación del virus en epizootias ocurridas en tres zonas de la región (Municipios de Valledupar, La Paz y Santa Marta. Por fecha de inicio de síntomas los casos comenzaron en la semana 51 de 2003 y el pico epidémico fue en la semana 1 de 2004; el último caso se confirmó el 22 de enero de 2004. Se confirmaron 29 casos de 787 notificados (15 del distrito de Santa Marta, 8 del departamento del Cesar y 6 de La Guajira; 20% de los casos fueron captados por vigilancia activa. El 28% fue confirmado por patología e inmunohistoquímica y el restante por IgM. El grupo de edad con mayor incidencia fue 15 a 44 años (75%, hombres (72% y agricultores (45%. La letalidad fue 28%.

    La vigilancia entomológica reportó la presencia de Sabethes s.p en Valledupar y los índice médicos, excepto en esta última ciudad, fueron mayores del 10%. Las coberturas de

  8. The effect of malnutrition on norovirus infection.

    Science.gov (United States)

    Hickman, Danielle; Jones, Melissa K; Zhu, Shu; Kirkpatrick, Ericka; Ostrov, David A; Wang, Xiaoyu; Ukhanova, Maria; Sun, Yijun; Mai, Volker; Salemi, Marco; Karst, Stephanie M

    2014-03-04

    Human noroviruses are the primary cause of severe childhood diarrhea in the United States, and they are of particular clinical importance in pediatric populations in the developing world. A major contributing factor to the general increased severity of infectious diseases in these regions is malnutrition-nutritional status shapes host immune responses and the composition of the host intestinal microbiota, both of which can influence the outcome of pathogenic infections. In terms of enteric norovirus infections, mucosal immunity and intestinal microbes are likely to contribute to the infection outcome in substantial ways. We probed these interactions using a murine model of malnutrition and murine norovirus infection. Our results reveal that malnutrition is associated with more severe norovirus infections as defined by weight loss, impaired control of norovirus infections, reduced antiviral antibody responses, loss of protective immunity, and enhanced viral evolution. Moreover, the microbiota is dramatically altered by malnutrition. Interestingly, murine norovirus infection also causes changes in the host microbial composition within the intestine but only in healthy mice. In fact, the infection-associated microbiota resembles the malnutrition-associated microbiota. Collectively, these findings represent an extensive characterization of a new malnutrition model of norovirus infection that will ultimately facilitate elucidation of the nutritionally regulated host parameters that predispose to more severe infections and impaired memory immune responses. In a broad sense, this model may provide insight into the reduced efficacy of oral vaccines in malnourished hosts and the potential for malnourished individuals to act as reservoirs of emergent virus strains. IMPORTANCE Malnourished children in developing countries are susceptible to more severe infections than their healthy counterparts, in particular enteric infections that cause diarrhea. In order to probe the

  9. Ultrasensitive norovirus detection using DNA aptasensor technology.

    Directory of Open Access Journals (Sweden)

    Amanda Giamberardino

    Full Text Available DNA aptamers were developed against murine norovirus (MNV using SELEX (Systematic Evolution of Ligands by EXponential enrichment. Nine rounds of SELEX led to the discovery of AG3, a promising aptamer with very high affinity for MNV as well as for lab-synthesized capsids of a common human norovirus (HuNoV outbreak strain (GII.3. Using fluorescence anisotropy, AG3 was found to bind with MNV with affinity in the low picomolar range. The aptamer could cross-react with HuNoV though it was selected against MNV. As compared to a non-specific DNA control sequence, the norovirus-binding affinity of AG3 was about a million-fold higher. In further tests, the aptamer also showed nearly a million-fold higher affinity for the noroviruses than for the feline calicivirus (FCV, a virus similar in size and structure to noroviruses. AG3 was incorporated into a simple electrochemical sensor using a gold nanoparticle-modified screen-printed carbon electrode (GNPs-SPCE. The aptasensor could detect MNV with a limit of detection of approximately 180 virus particles, for possible on-site applications. The lead aptamer candidate and the aptasensor platform show promise for the rapid detection and identification of noroviruses in environmental and clinical samples.

  10. BROTE DE SARAMPIÓN EN CAMPO DE GIBRALTAR, CÁDIZ, DURANTE EL PERÍODO FEBRERO-JULIO 2008

    Directory of Open Access Journals (Sweden)

    Juan Nieto Vera

    2010-01-01

    Full Text Available Fundamento: El 4 de febrero de 2008 se notificó a la Red de Vigilancia Epidemiológica de Andalucía (SVEA, 2 casos de sarampión vinculados epidemiológicamente, 2 tripulantes del Fast-Ferry Jaime I de la Compañía Balearia, que realiza la línea de Algeciras - Tánger. El objetivo de este trabajo es caracterizar epidemiológicamente el brote de ámbito poblacional detectado en la Comarca Campo de Gibraltar, las medidas de control implementadas y la efectividad vacunal. Método: Estudio observacional descriptivo de casos notificados. Se analizan las variables edad, sexo, municipio de residencia, sintomatología, fecha de inicio, colectivos implicados, estado vacunal previo, intervenciones realizadas, genotipo del virus, y efectividad vacunal. Fuentes de información los registros del SVEA, programa de vacunas e historia digital individual (Diraya. Se calcularon tasas x 105 por grupo de edad y medidas de frecuencia. Para comparación de efectividad vacunal se utilizó test Chi2. Resultados: Se confirmaron 155 casos de sarampión, 88.4% por laboratorio. Grupos de edad mas afectados menores de 2 años (19% y de 21 a 40 (51%. El 54.2% varones. El 72,14% no estaban vacunados. Se aisló virus sarampión Genotipo D4 importado. La efectividad vacunal era superior al 99%. Conclusiones: Se confirma un brote por virus del sarampión importado. Mas de la mitad de los casos no estaban vacunados. La disminución de la incidencia en vacunados hace necesario recomendar campañas de Cacht - Up que aumenten las coberturas para evitar la aparición de estos brotes vacunales.

  11. Tipificación molecular del virus dengue 3 durante el brote epidémico de dengue clásico en Lima, Perú, 2005

    Directory of Open Access Journals (Sweden)

    Enrique Mamani Z

    2005-07-01

    Full Text Available Objetivos: Identificar mediante trascripción reversa-reacción en cadena de la polimerasa (RT-PCR y sitios específicos de restricción - reacción en cadena de la polimerasa (RSS-PCR al agente causal del brote epidémico presentado en el distrito de Comas, Lima en abril del año 2005. Materiales y métodos: veinte muestras de suero colectadas durante el brote de dengue fueron procesados por RT-PCR para determinar el serotipo, esta técnica se realizó en un solo paso. Luego se aplicó la técnica RSS-PCR para la identificación del genotipo circulante y se corroboraron los resultados posteriormente con aislamiento viral y secuenciamiento. Resultados: El análisis del RTPCR del ARN extraído de las muestras presentó un producto amplificado de 290pb que corresponden al dengue serotipo 3 (DEN 3. El análisis de los productos de RSS-PCR del ARN extraído a partir de aislamientos de DEN 3 correspondió al patrón C, incluido en el genotipo III. Los aislamientos de los virus dengue 3 en líneas celulares C6/36, tipificadas por IFI y el secuenciamiento genético confirmaron los resultados obtenidos por las pruebas previamente descritas. Conclusión: Durante el brote epidémico de dengue clásico en Lima, circuló el genotipo III del virus DEN 3.

  12. Brote de diarrea asociado a Shigella sonnei debido a contaminación hídrica, San José, Costa Rica, 2001

    OpenAIRE

    Barrantes-Jiménez, Kenia; Pardo, Vekoh; Achí-Araya, Rosario

    2004-01-01

    artículo arbitrado -- Universidad de Costa Rica, Instituto de investigaciones en Salud. 2004. En julio del 2001, un brote de diarrea asociado a transmisión hidrica afecto a mas de 7000 personas residentes en el área urbana de San Jose. Desde su inicio se especulo sobre el papel de Shige- Ila spp., como uno de los posibles agentes etiologicos del mismo, por lo que el objetivo de este estudio fue determinar la presencia de esta bacteria en los cases de diarrea aten...

  13. Control de la polilla de brote del pino: uso de la ferómona de atracción sexual

    OpenAIRE

    Belmar, Julio; M

    2013-01-01

    En Chile, la polilla del brote del pino (rhyacionia buoliana) fue detectada por primera vez en 1985, desde entonces la población de este insecto se ha extendido hasta llegar a constituir la principal plaga forestal del país. Cubre alrededor del 90% de la superficie plantada con pino (1.400.000 has)La superficie plantada con pino corresponde a un 75% de las plantaciones forestales. Esta situación es motivo de preocupación de organismos de gobierno como CONAF y de las empresas forestales. En es...

  14. Transmission of Norovirus Within Households in Quininde, Ecuador.

    Science.gov (United States)

    Gastañaduy, Paul A; Vicuña, Yosselin; Salazar, Fabian; Broncano, Nely; Gregoricus, Nicole; Vinjé, Jan; Chico, Martha; Parashar, Umesh D; Cooper, Philip J; Lopman, Ben

    2015-09-01

    We studied the transmission of norovirus infection in households in Quininde, Ecuador. Among household contacts of norovirus positive children with diarrhea, norovirus negative children with diarrhea and asymptomatic controls, infection attack rates were 33%, 8% and 18%, respectively (N = 45, 36, 83). Infection attack rates were higher when index children had a higher viral load.

  15. Brote de varicela en el Servicio de Oncología de hombres del Hospital San Juan de Dios, febrero-abril de 2004, San José, Costa Rica

    Directory of Open Access Journals (Sweden)

    Sócrates Vargas-Naranjo

    2008-03-01

    Full Text Available Justificación y objetivo:La infección intrahospitalaria por varicela en adultos es infrecuente, a pesar de ser una enfermedad altamente contagiosa. Es reconocido que en adultos se presentan las tasas de letalidad más altas y por ello es importante analizar las características del presente brote y así determinar cuáles factores contribuyeron a que ocurriera, para recomendar acciones dirigidas a la prevención de un brote similar. Métodos: Se diseñó un estudio de casos y controles para identificar los factores asociados al brote por varicela en el hospital. La prueba de U de Mann-Whitney se utilizó para valorar diferencias entre casos y controles según edad, contacto entre pacientes, estancia hospitalaria y grupo de cama. El cálculo de los Odds Ratio ayudó a determinar la posible asociación entre las variables y la presentación de la enfermedad. Se recomendó la cuarentena del Servicio. Resultados:El primer caso de varicela ocurrió en febrero, al tercer día de su ingreso al hospital. Posteriormente, se presentaron 5 casos más. Al analizar las variables estudiadas, la curva epidémica y el período de incubación, la variable contacto entre los pacientes fue la más importante para mantener la existencia del brote p < 0,05; R = 25; [IC95%]=2,3 - 275,7. Conclusión:Se confirmó la transmisión persona-persona de la varicela como fuente principal de contagio en el hospital. Si bien la cuarentena permitió detener el brote, se deben tomar medidas más prácticas y menos costosas, que prevengan la aparición de un brote similar.

  16. Brotes escolares de gripe (H1N1 2009 en Cataluña

    Directory of Open Access Journals (Sweden)

    Nuria Torner

    2011-01-01

    Full Text Available A pesar de los avances en el conocimiento del virus de la gripe (H1N1 2009, la eficacia de su transmision entre contactos, asi como la eficacia de las intervenciones no farmacologicas es poco conocida. El objetivo de este trabajo es caracterizar la ocurrencia de brotes confirmados de virus (H1N1 2009 en Cataluna en el ambito escolar durante el periodo pandemico y evaluar las actuaciones llevadas a cabo para su control. Metodos: Se estudio la incidencia de brotes de VGA(H1N12009 de mayo a diciembre 2009. Se calcularon las tasas de ataque en funcion de emision de recomendaciones preventivas y ejecucion de intervenciones. La asociacion entre variables se calculo mediante ¿Ô2, comparacion de medias mediante t-Student y comparacion de proporciones mediante estadistico z , estableciendo el grado de significacion estadistica en ¿¿=0,05. Resultados: En total se notificaron 238 brotes. La TA global fue del 15,5%. Del total de brotes solo se conoce la tasa de ataque de 173 (72,7%, de los cuales 142 (82,1%; p<0,001 tuvieron una TA inferior al 25%. El principal ambito de transmision fue el escolar, donde se produjeron 209 (88%; p<0,001 brotes, de los cuales 187 (78,6%; p<0,001 correspondian a centros educativos. La duracion media de los brotes fue significativamente menor en funcion de la emision de recomendaciones (p=0,04. Conclusiones: El estudio de los brotes de gripe A/H1N1 2009 permite evidenciar que la adopcion de medidas preventivas y de higiene es de vital importancia para el control de la transmision en centros educativos.

  17. Micropropagación de chayote (sechium edule jacq. Sw. a partir de brotes vegetativos

    Directory of Open Access Journals (Sweden)

    Ana Abdelnour

    2002-01-01

    Full Text Available El chayote (Sechium edule es una importante fuente de divisas para los países exportadores, entre los que Costa Rica mantiene el liderazgo mundial. Entre los factores más limitantes para su producci ón se encuentra el material de siembra, tradicionalmente la semilla, que por su naturaleza no permite la obtención de una producción morfológicamente homogénea de frutos (color, forma y textura de la epidermis motivo de los altos porcentajes de rechazo en las plantas empacadoras. El establecimiento de una metodología de propagación vegetativa de la especie ayudaría a resolver los problemas de heterogeneidad. Por lo anterior, la presente investigación se dirigió a desarrollar un método de micropropagación a partir de brotes vegetativos. Se evaluó el efecto de varios desinfectantes y concentraciones de reguladores de crecimiento en las etapas de establecimiento, multiplicación y enraizamiento de dos cultivares comerciales. Se observó que una desinfección con hipoclorito de calcio al 4% permitió el mayor porcentaje de explantes establecidos asépticamente bajo condiciones in vitro (49%. También se observó que durante las etapas posteriores de la micropropagación, los requerimientos de reguladores de crecimiento fueron muy bajos (0,1 mgL-1 de BA en la etapa de brotación de yemas y de 0,1 a 0,2 mgL-1 de AIB durante el enraizamiento o no se requirieron (etapa de multiplicaci ón de microestacas.

  18. Investigación de un brote de fiebre de origen desconocido en una localidad colombiana del Caribe

    Directory of Open Access Journals (Sweden)

    José Laguado

    2005-12-01

    Full Text Available Objetivo. Realizar un estudio serológico de un brote de fiebre tropical de origen desconocido (FOD en una zona del departamento de Córdoba, donde hay agentes etiológicos comunes de la región como Plasmodium, Leptospira, Rickettsia, Salmonella, Brucella y Orienta. Materiales y métodos. En el municipio de Chimá (Córdoba se presentó un brote de FOD. Los casos se recopilaron de un grupo de 209 pacientes sintomáticos que asistieron a la consulta. De ellos, en 89 (42.6% se obtuvo información clínica, epidemiológica y exámenes paraclínicos. Para establecer la causa de la FOD, se hicieron estudios serológicos y de laboratorio para leptospirosis, dengue, salmonelosis, rickettsiosis, Orienta, brucelosis y malaria. Resultados. Los siguientes síntomas y signos se presentaron en 30.4% del total de la población estudiada: cefalea (66%, artralgias (40% fiebre y cefalea (62.9%. A pesar de serologías positivas para Rickettsia, Salmonella y Leptospira, se consideró que la causa de la FOD en la población fue una infección aguda producida por un flavivirus y que se sospechó como dengue. La positividad de anticuerpos anti-dengue IgM fue en 45% de los casos (40/89. La IgG se encontró en 89% de los pacientes antes negativos para IgM. Además, 44% de los pacientes fueron positivos para IgG e IgM; 30% de los casos se presentaron asociados con Leptospira (n=8, pero no se pudo determinar si estas infecciones fueron recientes o pasadas. Conclusión. Después de un estudio epidemiológico, serológico y de laboratorio de siete enfermedades tropicales, se estableció que el brote de FOD se debió presumiblemente al virus de dengue.

  19. Investigación de un brote de fiebre de origen desconocido en una localidad colombiana del Caribe.

    Directory of Open Access Journals (Sweden)

    José Laguado

    2009-11-01

    Full Text Available OBJETIVO: Realizar un estudio serológico de un brote de fiebre tropical de origen desconocido (FOD en una zona del departamento de Córdoba, donde hay agentes etiológicos comunes de la región como Plasmodium, Leptospira, Rickettsia, Salmonella, Brucella y Orienta. MATERIALES Y MÉTODOS: En el municipio de Chimá (Córdoba se presentó un brote de FOD. Los casos se recopilaron de un grupo de 209 pacientes sintomáticos que asistieron a la consulta. De ellos, en 89 (42.6% se obtuvo información clínica, epidemiológica y exámenes paraclínicos. Para establecer la causa de la FOD, se hicieron estudios serológicos y de laboratorio para leptospirosis, dengue, salmonelosis, rickettsiosis, Orienta, brucelosis y malaria. RESULTADOS: Los siguientes síntomas y signos se presentaron en 30.4% del total de la población estudiada: cefalea (66%, artralgias (40% fiebre y cefalea (62.9%. A pesar de serologías positivas para Rickettsia, Salmonella y Leptospira, se consideró que la causa de la FOD en la población fue una infección aguda producida por un flavivirus y que se sospechó como dengue. La positividad de anticuerpos anti-dengue IgM fue en 45% de los casos (40/89. La IgG se encontró en 89% de los pacientes antes negativos para IgM. Además, 44% de los pacientes fueron positivos para IgG e IgM; 30% de los casos se presentaron asociados con Leptospira (n=8, pero no se pudo determinar si estas infecciones fueron recientes o pasadas. CONCLUSIÓN: Después de un estudio epidemiológico, serológico y de laboratorio de siete enfermedades tropicales, se estableció que el brote de FOD se debió presumiblemente al virus de dengue.

  20. El hospital ante un brote prolongado de legionelosis The hospital faced with a prolonged Legionella outbreak

    Directory of Open Access Journals (Sweden)

    Juan Antonio Fernández

    2004-08-01

    Full Text Available Objetivo: Describir los recursos asistenciales utilizados en pacientes hospitalizados por neumonía por Legionella durante un brote ocurrido en Alcoy y compararlos con los empleados en otras neumonías. Métodos y resultados: Mediante un protocolo, se analiza y compara a 177 pacientes con neumonía por Legionella con 180 pacientes ingresados por otras neumonías, y se describe su tratamiento y los recursos empleados. La claritromicina fue el antibiótico más utilizado en ambos grupos. La estancia hospitalaria fue similar, pero los requerimientos de ventilación mecánica y cuidados intensivos fueron superiores para Legionella. La hospitalización domiciliaria se utilizó con éxito en un 15,6% de los pacientes con Legionella y en un 11,3% de los demás. El uso de oxigenoterapia domiciliaria al alta fue menor para Legionella (7,8% que para el resto de neumonías (16,7%. Conclusiones: Se destaca la mayor necesidad de ventilación mecánica en la neumonía por Legionella y los buenos resultados de la hospitalización domiciliaria dentro de los nuevos sistemas de gestión.Objective: To describe the health resources used in patients hospitalized with Legionella pneumonia during an outbreak of Legionnaire's disease in Alcoy (Spain, and to compare them with those used in other forms of pneumonia. Methods and results: Using a clinical protocol, 177 Legionella pneumonia patients were compared with 180 patients hospitalized for other types of pneumonia. Data on therapy and the resources used were collected. The most common antibiotic treatment in both groups was clarithromycin, but intensive care and mechanical ventilation requirements were greater in Legionella pneumonia. Home-based hospital care was successfully used in 15.6% of patients with Legionella pneumonia and in 11.3% of those with other types of pneumonia. Home oxygen therapy after discharge was less frequent in the Legionella pneumonia group (7.8% than in the group with non

  1. Decoding norovirus infection in Crohn's disease.

    Science.gov (United States)

    Chamaillard, Mathias; Cesaro, Annabelle; Lober, Pierre-Emmanuel; Hober, Didier

    2014-04-01

    Although a causing viral infectious agent remains untraceable in Crohn's disease, most recent genome-wide association studies have linked the FUT2 W143X mutation (resulting in asymptomatic norovirus infection) with the pathogenesis of Crohn's ileitis and with vitamin B12 deficiency (i.e., a known risk factor for Crohn's disease with ileal involvement). In line with these findings, host variations in additional genes involved in host response to norovirus infection (such as ATG16L1 and NOD2) predispose humans to Crohn's ileitis. One may therefore presume that asymptomatic norovirus infection may contribute to disruption of the stability of the gut microbiota leading to Crohn's ileitis. These paradigms highlight not only the need to revisit the potential transmissibility of Crohn's disease, but also potential safety issues of forthcoming clinical trials on human probiotic infusions in Crohn's ileitis by rigorous donors screening program.

  2. Vital Signs-Preventing Norovirus Outbreaks

    Centers for Disease Control (CDC) Podcasts

    2014-06-03

    This podcast is based on the June 2014 CDC Vital Signs report. Norovirus infects about 20 million Americans each year. Learn how to protect yourself and your family from this very contagious, potentially serious illness.  Created: 6/3/2014 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 6/3/2014.

  3. Global Economic Burden of Norovirus Gastroenteritis.

    Directory of Open Access Journals (Sweden)

    Sarah M Bartsch

    Full Text Available Despite accounting for approximately one fifth of all acute gastroenteritis illnesses, norovirus has received comparatively less attention than other infectious pathogens. With several candidate vaccines under development, characterizing the global economic burden of norovirus could help funders, policy makers, public health officials, and product developers determine how much attention and resources to allocate to advancing these technologies to prevent and control norovirus.We developed a computational simulation model to estimate the economic burden of norovirus in every country/area (233 total stratified by WHO region and globally, from the health system and societal perspectives. We considered direct costs of illness (e.g., clinic visits and hospitalization and productivity losses.Globally, norovirus resulted in a total of $4.2 billion (95% UI: $3.2-5.7 billion in direct health system costs and $60.3 billion (95% UI: $44.4-83.4 billion in societal costs per year. Disease amongst children <5 years cost society $39.8 billion, compared to $20.4 billion for all other age groups combined. Costs per norovirus illness varied by both region and age and was highest among adults ≥55 years. Productivity losses represented 84-99% of total costs varying by region. While low and middle income countries and high income countries had similar disease incidence (10,148 vs. 9,935 illness per 100,000 persons, high income countries generated 62% of global health system costs. In sensitivity analysis, the probability of hospitalization had the largest impact on health system cost estimates ($2.8 billion globally, assuming no hospitalization costs, while the probability of missing productive days had the largest impact on societal cost estimates ($35.9 billion globally, with a 25% probability of missing productive days.The total economic burden is greatest in young children but the highest cost per illness is among older age groups in some regions. These large

  4. Norovirus infections in preterm infants: wide variety of clinical courses

    OpenAIRE

    Zimmermann Kathrin; Olbertz Dirk; Kramer Axel; Armbrust Sven; Fusch Christoph

    2009-01-01

    Abstract Background Norovirus is an important cause of nonbacterial acute gastroenteritis in all ages. Atypical courses are described. Clinical symptoms are diarrhea, vomiting, nausea, abdominal cramps, fever and malaise. Apart from three recent short reports we describe for the first time an outbreak of norovirus in a tertiary Neonatal Intensive Care Unit. Findings The typical symptoms of norovirus infection are in part also seen in premature born infants but with a different pattern and a h...

  5. Diagnóstico temprano en un brote epidémico del virus Dengue en Piura usando RT-PCR y nested-PCR

    Directory of Open Access Journals (Sweden)

    Oscar Nolasco

    1997-07-01

    Full Text Available Un test de diagnóstico temprano (RT-PCR y Nested-PCR fue evaluado y comparado con métodos convencionales (cultivo in vitro, IFI y MAC-ELISA. Treinta y cuatro sueros de pacientes correspondientes de un brote epidémico de la costa norte peruana (Mancora, Piura en mayo de 1997 fueron incluidos en este estudio. Todos los sueros fueron obtenidos de pacientes que presentaron en los primeros cinco días manifestaciones clínicas siendo diagnosticados luego como dengue serotipo 1. Asimismo, RT-PCR permitió diagnosticar 82% de los sueros (28/34, sin embargo Mac-ELISA y cultivo in vitro reconocieron unicamente 41% de los sueros (14/34 y 38% de los sueros (13/34 respectivamente. Por lo tanto, el uso de esta herramienta molecular (RT-PCR y Nested-PCR permitiró dar un diagnóstico temprano a estos pacientes y actuar inmediatamente ante la presencia de un brote epidémico.

  6. Estudio de un brote de bacteremia secundaria asociada con nutrición parenteral en una unidad de recién nacidos de tercer nivel.

    Directory of Open Access Journals (Sweden)

    Jaime A. del Río

    2009-10-01

    Full Text Available Ante la evidencia de un brote de bacteremia secundaria neonatal, en la Unidad de Recién Nacidos, Hospital de Caldas, Manizales, se realizó un estudio de casos y controles 1:4, para determinar la asociación de factores de riesgo importantes para los pediatras como nutrición parenteral, terapia respiratoria, tubo orotraqueal, cámara cefálica, parto vaginal, la aplicación de hemoderivado, remisión de otra unidad, leche materna por sonda, peso y edad. Como definición de caso se adoptó la clínica con por lo menos dos hemocultivos positivos, patógeno de piel hemocultivado y germen aislado en sangre sin foco definido. Los 19 controles se tomaron al azar de los recién nacidos que se encontraban hospitalizados por otras causas diferentes o relacionadas con la patología. Se realizó una regresión logística paso a paso, para determinar los eventos causales. Los gérmenes hemocultivados fueron Escherichia coli, Enterobacter gergoviae, E. aerogenes y E. cloacae. La edad promedio de los casos fue 30.6 semanas, en los controles 36.6 meses (p 0.2 NS. Peso promedio de los casos 1,385 g contra 2,621 g en los controles. Se encontró asociada la nutrición parenteral con el brote OR=15 (IC=1-482 p 0.027 S. Otros factores como la edad y el peso fueron de confusión. En cuanto a la nutrición parenteral, se corroboró su implicación, porque al revisar de inmediato el proceso de nutrición parenteral se encontró que los productos sobrantes se estaban almacenando y reutilizando hasta por 30 días.

  7. Structural Basis for Norovirus Inhibition and Fucose Mimicry by Citrate

    Energy Technology Data Exchange (ETDEWEB)

    Hansman, Grant S.; Shahzad-ul-Hussan, Syed; McLellan, Jason S.; Chuang, Gwo-Yu; Georgiev, Ivelin; Shimoike, Takashi; Katayama, Kazuhiko; Bewley, Carole A.; Kwong, Peter D. (NIAID)

    2012-01-20

    Human noroviruses bind with their capsid-protruding domains to histo-blood-group antigens (HBGAs), an interaction thought to direct their entry into cells. Although human noroviruses are the major cause of gastroenteritis outbreaks, development of antivirals has been lacking, mainly because human noroviruses cannot be cultivated. Here we use X-ray crystallography and saturation transfer difference nuclear magnetic resonance (STD NMR) to analyze the interaction of citrate with genogroup II (GII) noroviruses. Crystals of citrate in complex with the protruding domain from norovirus GII.10 Vietnam026 diffracted to 1.4 {angstrom} and showed a single citrate bound at the site of HBGA interaction. The citrate interaction was coordinated with a set of capsid interactions almost identical to that involved in recognizing the terminal HBGA fucose, the saccharide which forms the primary conserved interaction between HBGAs and GII noroviruses. Citrate and a water molecule formed a ring-like structure that mimicked the pyranoside ring of fucose. STD NMR showed the protruding domain to have weak affinity for citrate (460 {mu}M). This affinity, however, was similar to the affinities of the protruding domain for fucose (460 {mu}M) and H type 2 trisaccharide (390 {mu}M), an HBGA shown previously to be specifically recognized by human noroviruses. Importantly, competition STD NMR showed that citrate could compete with HBGA for norovirus binding. Together, the results suggest that citrate and other glycomimetics have the potential to block human noroviruses from binding to HBGAs.

  8. Structural basis for norovirus inhibition and fucose mimicry by citrate.

    Science.gov (United States)

    Hansman, Grant S; Shahzad-Ul-Hussan, Syed; McLellan, Jason S; Chuang, Gwo-Yu; Georgiev, Ivelin; Shimoike, Takashi; Katayama, Kazuhiko; Bewley, Carole A; Kwong, Peter D

    2012-01-01

    Human noroviruses bind with their capsid-protruding domains to histo-blood-group antigens (HBGAs), an interaction thought to direct their entry into cells. Although human noroviruses are the major cause of gastroenteritis outbreaks, development of antivirals has been lacking, mainly because human noroviruses cannot be cultivated. Here we use X-ray crystallography and saturation transfer difference nuclear magnetic resonance (STD NMR) to analyze the interaction of citrate with genogroup II (GII) noroviruses. Crystals of citrate in complex with the protruding domain from norovirus GII.10 Vietnam026 diffracted to 1.4 Å and showed a single citrate bound at the site of HBGA interaction. The citrate interaction was coordinated with a set of capsid interactions almost identical to that involved in recognizing the terminal HBGA fucose, the saccharide which forms the primary conserved interaction between HBGAs and GII noroviruses. Citrate and a water molecule formed a ring-like structure that mimicked the pyranoside ring of fucose. STD NMR showed the protruding domain to have weak affinity for citrate (460 μM). This affinity, however, was similar to the affinities of the protruding domain for fucose (460 μM) and H type 2 trisaccharide (390 μM), an HBGA shown previously to be specifically recognized by human noroviruses. Importantly, competition STD NMR showed that citrate could compete with HBGA for norovirus binding. Together, the results suggest that citrate and other glycomimetics have the potential to block human noroviruses from binding to HBGAs.

  9. Regeneración in vitro de brotes de Polianthes tuberosa L. a partir de yemas vegetativas de la inflorescencia y de tejido de cormo

    Directory of Open Access Journals (Sweden)

    Fanny Hernández-Mendoza

    2014-01-01

    Full Text Available Polianthes tuberosa L. es una planta endémica de México, comercialmente se cultiva para flor de corte, y, además, es utilizada en la industria farmacéutica y del perfume. Tradicionalmente, los productores la propagan utilizando los cormos, lo que ha ocasionado que el cultivo presente poca variabilidad genética y posiblemente, por esta razón solo se conocen cultivares con flores blancas. Con base en lo anterior el objetivo de la presente investigación consistió en establecer la metodología práctica y competitiva para propagar in vitro Polianthes tuberosa L. Las yemas y pequeños segmentos de tejido de cormo fueron colocadas sobre la superficie del medio de cultivo, base GC (comunicación personal Guillermo Carrillo con las sales inorgánicas del medio de cultivo Murashige y Skoog (1962 por litro, 50 mL de agua de coco, 20 g de sacarosa, 6.4 g de agar y el pH fue ajustado a 5.7. Con este medio básico se prepararon medios de cultivo que contenían bencilaminopurina (BAP, ácido naftalenacético (ANA, ácido 2,4-diclorofenoxiacético (2,4-D, ácido indolacético (AIA, y cinetina. La formación de brotes que dieron origen a las plántulas ocurrió mediante, la regeneración directa de la yema floral la cual al crecer forma sólo una plántula y a partir del tejido de la base de la yema, de esta región se obtuvieron hasta seis brotes por yema en el medio que contiene BAP, 4.5 mg y ANA, 0.1 mg, del cual la regeneración de brotes fue mayor (56.1 %. En el caso de cormo el problema fue la contaminación llegando en algunos casos hasta el 100 % de los cultivos. Es de resaltar la importancia de poder lograr la regeneración masiva in vitro de plantas de nardo a partir de yemas florales.

  10. Brotes de diarrea e intoxicaciones transmitidas por alimentos en Costa Rica, 2005

    OpenAIRE

    Hilda Ma Bolaños-Acuña; María Teresa Acuña-Calvo; Francisco Duarte-Martínez; Wagner Salazar-Castro; Gletty Oropeza-Barrios; Luz Marina Sánchez-Salazar; Elena Campos-Chacón

    2007-01-01

    Justificación y objetivo: En la actualidad, las enfermedades de transmisión alimentaria, incluyendo las diarreas e intoxicaciones, constituyen uno de los problemas de salud pública de mayor importancia a nivel mundial, ya que ocasionan alta morbilidad y mortalidad, generan grandes costos a los servicios de salud, pérdidas económicas, demandas y pérdida de confianza de los consumidores. El objetivo del trabajo es analizar la información disponible en el Centro Nacional de Referencia en Bacteri...

  11. Brote de varicela en Herrera del Duque (Badajoz Chickenpox outbreak in Herrera del Duque, Badajoz, Spain

    Directory of Open Access Journals (Sweden)

    F.J. Valadés

    2003-06-01

    Full Text Available Introducción: La varicela es una enfermedad de distribución mundial con una elevada morbilidad y pocas complicaciones, aunque puede presentar cuadros clínicos graves en inmunodeprimidos y adultos sanos. El objeto de este estudio es identificar y describir las características y los costes de un brote epidémico en Extremadura, cuya tasa anual de casos declarados al sistema de Enfermedades de Declaración Obligatoria (EDO oscila en alrededor de 5 por 1.000 habitantes. Métodos: Estudio descriptivo con búsqueda activa de casos entre los meses de noviembre del año 2000 y marzo de 2001, y de la susceptibilidad de la cohorte escolarizada del colegio de Herrera del Duque (Badajoz. Las definiciones de casos fueron recogidas de los protocolos de la Red de Vigilancia de la comunidad extremeña. La confirmación microbiológica se realizó por aislamiento del virus y por presencia de marcadores IgM e IgG en el suero del enfermo. Se analizaron los costes tangibles directos e indirectos y los no tangibles del brote. Resultados: De los 75 casos identificados, 71 (94,7% eran niños de entre uno y 9 años, predominando el sexo masculino. La tasa de ataque fue de 18,5 casos por 1.000 habitantes, y del 68,2% en convivientes menores de 10 años. La evolución fue benigna, sin ingresos hospitalarios ni complicaciones. Se encontró un 71,6% de niños susceptibles en los de entre 3 y 8 años. Se analizó una posible agregación temporal de casos en el colegio, obteniéndose un riesgo relativo (RR de 5,01 (p Introduction: Chickenpox is a worldwide disease with high morbidity but few complications, although complications can be sevre in immunocompromised individuals and healthy adults. The annual chickenpox rate declared to the National Notification Disease Surveillance System is approximately 5 cases per 1,000 inhabitants in Extremadura (Spain. The aim of this study was to identify and describe the characteristics and cost of an epidemic outbreak of chickenpox

  12. Norovirus Prevention (A Minute of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2014-06-12

    Nearly one in 15 people in the U.S. gets sick from norovirus each year and up to 800 die. This podcast discusses the importance of hand washing, and other ways to prevent the spread of noroviruses.  Created: 6/12/2014 by MMWR.   Date Released: 6/12/2014.

  13. Norovirus Prevention (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2014-06-12

    If you’re suffering from vomiting and diarrhea, you might be among the millions of Americans who get sick from norovirus each year. In this podcast, Dr. Aron Hall discusses ways to prevent norovirus outbreaks from contaminated food.  Created: 6/12/2014 by MMWR.   Date Released: 6/12/2014.

  14. Norovirus genotype profiles associated with foodborne transmission, 1999–2012

    NARCIS (Netherlands)

    L. Verhoef; J. Hewitt (Joanne); L. Barclay (Leslie); S.M. Ahmed (Sharia M.); R. Lake (Rob); A.J. Hall (Aron J.); B.A. Lopman (Benjamin A.); A. Kroneman; H. Vennema (Harry); J. Vinjé (Jan); M.P.G. Koopmans D.V.M. (Marion)

    2015-01-01

    textabstractWorldwide, noroviruses are a leading cause of gastroenteritis. They can be transmitted from person to person directly or indirectly through contaminated food, water, or environments. To estimate the proportion of foodborne infections caused by noroviruses on a global scale, we used norov

  15. Six Tips to Help Prevent the Spread of Norovirus

    Centers for Disease Control (CDC) Podcasts

    2013-08-27

    Dr. Aron Hall, a CDC epidemiologist specializing in noroviruses, discusses six tips to help prevent the spread of norovirus.  Created: 8/27/2013 by National Center for Immunization and Respiratory Diseases (NCIRD), Division of Viral Diseases (DVD).   Date Released: 8/27/2013.

  16. Estudio de un brote epidémico de tos ferina en Castellón

    Directory of Open Access Journals (Sweden)

    González Morán Francisco

    2002-01-01

    Full Text Available Fundamento: A partir de la declaración de varios casos en un centro escolar se inicia el estudio de brote con el objetivo de caracterizar éste desde el punto de vista de persona, lugar y tiempo; se calcula la efectividad de la vacuna, y se estudia la concordancia entre los casos y el resultado positivo del estudio serológico. Métodos: Se define caso a la persona que presenta tos persistente de dos semanas de duración. Se realiza estudio de la difusión de la enfermedad a través de la curva epidémica, y de la efectividad de la dosis de refuerzo de la vacuna antipertussis. La concordancia entre los casos y la serología positiva se evalúa por el índice Kappa. Resultados: Entre los alumnos de varios centros escolares y sus convivientes se encuesta a 130 personas, de los que 94 entran en la definición de caso. La media de edad de los casos es 10,5 años, un 42,6% son varones, el 84% escolares, el 71,3% muestra signos de infección reciente (IgM positiva, y el tiempo medio desde la última dosis de vacuna antipertussis es de 8,25 años. La efectividad de la dosis de refuerzo de la vacuna es del 66%. La concordancia entre los casos y el resultado positivo de la serología muestra un Kappa igual a 0,45. No se aisló B. Pertussis en las 25 muestras de frotis faríngeo. Conclusiones: Las aulas y el medio familiar son un factor de difusión de la enfermedad. La inclusión de una dosis de refuerzo a los 18 meses mejora la efectividad de la vacuna antipertussis. El aislamiento de la B. Pertussis es poco frecuente, y la serología, puede ser una alternativa ante la sospecha clínica de la enfermedad.

  17. Vigilancia epidemiológica de enfermedades transmitidas por alimentos en la provincia de Río Negro, Argentina, 1993-2001 Surveillance of foodborne diseases in the Province of Rio Negro, Argentina, 1993 - 2001

    OpenAIRE

    Silvana Di Pietro; Karina Haritchabalet; Gustavo Cantoni; Liliana Iglesias; Sergio Mancini; Ana Temperoni; Jose L. Labanchi; Norma Barbarossa; María T. García; Mariela Cofre; Silvia Rosales; Eduardo Herrero; Ricardo Bigatti; Omar Orellana; Edmundo Larrieu

    2004-01-01

    Se describen 39 brotes de enfermedades transmitidas por alimentos que afectaron a 958 personas en la provincia de Río Negro, Argentina, en el período 1993- 2001. Se identifican los agentes causales, los alimentos involucrados, los sitios de ocurrencia, los factores de riesgo involucrados y los mecanismos de notificación empleados. Salmonella spp (38%), Trichinella spiralis (15%), Escherichia coli (13%) y Staphylococcus aureus (15%) resultaron los agentes más frecuentes en los brotes. Salmonel...

  18. Determinación de tamaño de muestra de características del xilema de brote de aguacate mediante remuestreo

    Directory of Open Access Journals (Sweden)

    Elizabeth Meza-Castillo

    2010-12-01

    Full Text Available El propósito de este trabajo fue determinar el tamaño de muestra adecuado, para detectar diferencias estadísticas en análisis de varianza de los caracteres de xilema, en brotes anuales de aguacate. Para esto, fueron registradas en tres árboles con altura contrastante las variables frecuencia, área, perímetro y diámetro de los vasos del xilema. A partir de 50 observaciones de cada árbol, se realizaron 5.000 remuestreos no paramétricos, para cada repetición de 2 a 50 campos microscópicos. A partir del tamaño de muestra de 15 repeticiones, las desviaciones en los cinco estadísticos son mínimas, por lo que se propone como el mínimo para el muestreo de dichas variables.

  19. Identification of immune and viral correlates of norovirus protective immunity through comparative study of intra-cluster norovirus strains.

    Directory of Open Access Journals (Sweden)

    Shu Zhu

    Full Text Available Whether or not primary norovirus infections induce protective immunity has become a controversial issue, potentially confounded by the comparison of data from genetically distinct norovirus strains. Early human volunteer studies performed with a norovirus-positive inoculum initially led to the conclusion that primary infection does not generate long-term, protective immunity. More recently though, the epidemiological pattern of norovirus pandemics has led to the extrapolation that primary norovirus infection induces herd immunity. While these are seemingly discordant observations, they may in fact reflect virus strain-, cluster-, or genogroup-specific differences in protective immunity induction. Here, we report that highly genetically related intra-cluster murine norovirus strains differ dramatically in their ability to induce a protective immune response: Primary MNV-3 infection induced robust and cross-reactive protection, whereas primary MNV-1 infection induced modest homotypic and no heterotypic protection. In addition to this fundamental observation that intra-cluster norovirus strains display remarkable differences in protective immunity induction, we report three additional important observations relevant to norovirus:host interactions. First, antibody and CD4⁺ T cells are essential to controlling secondary norovirus infections. Second, the viral minor structural protein VP2 regulates the maturation of antigen presenting cells and protective immunity induction in a virus strain-specific manner, pointing to a mechanism by which MNV-1 may prevent the stimulation of memory immune responses. Third, VF1-mediated regulation of cytokine induction also correlates with protective immunity induction. Thus, two highly genetically-related norovirus strains displayed striking differences in induction of protective immune responses, strongly suggesting that the interpretation of norovirus immunity and vaccine studies must consider potential virus

  20. Posibles Brotes de Zoonosis relacionadas a Huracanes (artículo de opinión)

    OpenAIRE

    2013-01-01

    En la actualidad es frecuente la presentación de fenómenos naturales con pérdidas potenciales o reales para los intereses humanos, alteraciones atribuidas al cambio climático y al calentabiento global. Esto es importante porque determina cambios en las rutas de las aves migratorias, potencialmente transmisoras de enfermedades como la influenza aviar, diferentes zoonosis y algunas enfermedades emergentes y reemergentes. Se presentan algunos datos sobre brotes que contextualizan la amenaza pote...

  1. Intoxicación alimentaria por Clostridium perfringens en el Centro Penitenciario de Atención Institucional de San José: estudio de cohorte retrospectivo

    OpenAIRE

    Roy Wong-Mc Clure; Armando Silva-Solórzano; Xiomara Badilla-Vargas

    2004-01-01

    Las enfermedades transmitidas por los alimentos se presentan anualmente en Costa Rica y por lo general se estudian hasta identificar el agente etiológico, pero no hasta determinar su fuente de contaminación. No se ha documentado la importancia de fortalecer la inocuidad de alimentos, lo cual produce eventos que comprometen la salud pública cada año, por lo que fue importante estudiar el presente brote. En este estudio se analiza el brote diarreico de un centro penitenciario de San José, en 20...

  2. Different norovirus genotypes in patients with gastroenteritis in Kuwait.

    Science.gov (United States)

    Al-Rashidi, Amirah; Chehadeh, Wassim; Szücs, György G; Albert, M John

    2013-09-01

    Norovirus is a leading cause of acute gastroenteritis worldwide. The importance of this virus infection in Kuwait is not known. Eight out of 100 stool samples (8.0%) from children up to 5 years of age with gastroenteritis studied during 2006-2007 from one hospital, and 6 out of 70 stool samples (8.5%) from similar children studied from another hospital during 2010-2011 were positive for norovirus by RT-PCR. Out of these 170 samples studied from both hospitals, 10 samples were positive for norovirus when tested by ELISA. Phylogenetic tree analysis of norovirus strains showed that 50% of the norovirus strains belonged to genotype GII.4, and the predominant strain was GII.4 2006b. Other detected genotypes were GII.12, GII.b, GII.3, GII.8, and GII.7. This study highlights the importance of screening for norovirus infection in acute gastroenteritis and having a reporting system to understand better the epidemiology of norovirus infection in Kuwait.

  3. Aplicación del teorema del umbral estocástico de Whittle a un brote de varicela Application of Whittle's stochastic threshold theorem to a chickenpox outbreak

    Directory of Open Access Journals (Sweden)

    Doracelly Hincapié Palacio

    2006-08-01

    Full Text Available OBJETIVO: Estimar el ritmo reproductivo básico en un brote de varicela, aplicar el teorema umbral estocástico para estimar la probabilidad de la ocurrencia del brote e identificar medidas preventivas. MÉTODOS: El estudio fue realizado en una guardería de 16 niños, con 13 susceptibles, un infectado inicial y dos niños inmunes por antecedente de enfermedad. Se partió de un modelo estocástico: susceptible - infectado - removido. Se estimó el ritmo de reproducción básico de la enfermedad R0, usando un método de máxima verosimilitud basado en el conocimiento de la distribución de probabilidades para el tamaño total de la epidemia y haciendo una aproximación de epidemia casi-completa. Con el R0 obtenido se aplicó el teorema de umbral estocástico para obtener algunas medidas preventivas que podrían impedir la irrupción del brote de varicela. RESULTADOS: Cada infectado inicial produjo tres casos nuevos de infección, requiriendo para impedir el brote, una cobertura mínima de vacunación del 62%, o disminuir en 62% el contacto entre miembros del grupo o aumentar en 170% la remoción de infectados. CONCLUSIONES: El teorema del umbral estocástico permite identificar medidas que se podrían implementar para prevenir y controlar brotes de varicela. Aunque la distribución del tamaño de la epidemia en forma bimodal con similar probabilidad de ocurrencia de brotes grandes y pequeños, señala la incertidumbre del proceso epidémico en grupos pequeños, requiriéndose un estrecho seguimiento de los brotes en tales grupos.OBJECTIVE: To estimate the basic reproductive rate of a chickenpox outbreak, to apply the stochastic threshold theorem to estimate the probability of an outbreak occurrence and to identify preventive measures. METHODS: The study was carried out in a daycare center comprising 16 children, 13 susceptible, one infected and two children with acquired immunity by previous disease. A stochastic susceptible - infected - removed

  4. Micropropagación de plantas de lechosa en recipientes de inmersión temporal a partir de brotes axilares Micropropagation of papaya plants in temporary immersion recipients from axilary shoots

    Directory of Open Access Journals (Sweden)

    Ariadne Vegas García

    2015-05-01

    Full Text Available Título en ingles: Micropropagation of papaya plants in temporary immersion recipients from axilary shootsTítulo corto: Micropropagación de lechosa en recipientes de inmersión temporal.Resumen: Se estandarizaron las condiciones de iniciación, multiplicación, enraizamiento y aclimatización de plantas hermafroditas de lechosa cv Maradol provenientes de brotes axilares, producidos en recipientes de inmersión temporal RITA®. En cada envase, contentivo de 200 ml de medio de cultivo líquido de Fitch, se colocaron cuatro brotes de 2 a 3 cm de longitud. Los biorreactores se conectaron a tres líneas de inmersión de 5, 2 y 1 min cada 4h y se colocaron 6 envases en promedio por línea, en condiciones de fotoperíodo de 16 h. Transcurridos 30 a 45 días, se cuantificaron los brotes y se clasificaron de acuerdo al tamaño: < 2 cm (pequeños, entre 2 a 3 cm (medianos,  ˃ 3 cm con y sin raíz (grandes. Los dos primeros tipos de brotes se continuaron multiplicando en los mismos medios; y los más elongados se aclimatizaron utilizando el Sistema Autotrófico Hidropónico (SAH. Se determinó la sanidad y la fidelidad de las plantas producidas mediante pruebas de ELISA y RAPD, respectivamente. Durante un periodo de 6 meses se reciclaron un total de 47 recipientes, los cuales produjeron 1.091 brotes: 377  pequeños; 482 medianos; 175 grandes sin raíz y 57 con raíz. Usando el SAH se obtuvo 89,5% de plantas aclimatizadas cuando se usaron brotes enraizados, y 41,6% a partir de brotes sin  raíces. Con la combinación de las técnicas RITA y SAH se logró un sistema continuo y eficiente de producción de plantas sanas y fieles al tipo, en comparación con los métodos convencionales de micropropagación y aclimatización.Palabras clave: Carica papaya, RITA®, sistema autotrófico, estabilidad genética.Abstract: We standardized initiation, multiplication, rooting and acclimatization conditions of papaya cv Maradol hermaphrodite plants from axillary

  5. Efectos de la cobertura vacunal previa en la dinamica de un brote de sarampion

    Directory of Open Access Journals (Sweden)

    Luna Sánchez Antonio

    1997-01-01

    Full Text Available FUNDAMENTO: La eficacia de una vacuna debería medirse mediante ensayos clínicos controlados, no obstante, aspectos éticos lo impiden. Orenstein sugiere que se estime la eficacia de una vacuna mediante, entre otros métodos, el estudio de los brotes epidémicos de la enfermedad caso de ser posible. El presente estudio plantea el cálculo de la eficacia vacunal en el terreno y de los efectos protectores de un programa de vacunación mediante el análisis de un brote epidémico de sarampión. MATERIAL Y MÉTODOS: Estudio de cohortes retrospectivo. La población de estudio la constituyó el grupo de niños nacidos en el municipio de Aznalcollar (localidad de 5.571 habitantes perteneciente al Distrito Sanitario Aljarafe-Sevilla entre dos brotes epidémicos de sarampión ocurridos en dicha localidad en los años 1986 y 1994. Se excluyeron de la cohorte a aquellos niños que a comienzos del brote de 1994 no habían cumplido la edad de vacunación y también a quienes tuvieron exposición anterior al virus, es decir los nacidos antes y durante la epidemia de 1986. El estudio incluyó a vacunados y no vacunados. Todos los casos cumplían los criterios diagnósticos establecidos. A todos los niños en seguimiento se les revisó sus antecedentes vacunales. Tras el cálculo de las tasas de ataque en vacunados y no vacunados, se determinaron la eficacia vacunal y los efectos indirectos totales y medios del programa de vacunación. RESULTADOS: La vacuna resultó eficaz en el 91'5 % de los vacunados. El programa de vacunación produjo una reducción del número de casos en los no vacunados del 78'9%, del 98% en los vacunados y del 92% en el conjunto de la cohorte estudiada, siendo la cobertura vacunal de la misma del 66'4%. CONCLUSIONES: Los efectos de la vacunación y la eficacia vacunal pueden y deben ser calculados aprovechando la aparición de brotes epidémicos caso de ser posible. Se recomienda incrementar las coberturas de vacunación de la poblaci

  6. Noroviruses on surfaces: Detection, transfer and inactivation

    OpenAIRE

    Rönnqvist, Maria

    2014-01-01

    Human noroviruses (HuNoVs) are a leading cause of foodborne gastroenteritis worldwide and spread easily among humans via the faecal-oral route. A low infective dose, a high viral load in the vomit and faeces of infected persons, a lack of long-term immunity following previous infection, and a high environmental stability of the viruses all enhance the spreading of HuNoV in the population. The aim of this doctoral thesis is to investigate the prevalence of HuNoVs on environmental surfaces...

  7. Brote de legionelosis asociado a un balneario Legionella outbreak at a spa

    Directory of Open Access Journals (Sweden)

    E. Serrano Ibarbia

    2001-06-01

    Full Text Available En 1998 el inicio de la temporada de actividad de un balneario en Gipuzkoa coincidió con la detección de un brote de legionelosis asociado al mismo, lo cual condujo al cierre de la instalación y al estudio epidemiológico -casos y controles- y ambiental oportunos. Se definió como caso toda persona que durante su estancia en el balneario o durante los 10 días siguientes presentará neumonía o un cuadro febril compatible con fiebre de Pontiac.El estudio ambiental incluyó la inspección del balneario y entorno y muestreos de los sistemas sanitarios de agua y de los elementos de hidroterapia.De las 287 personas encuestadas de la Comunidad Autónoma Vasca, el 12.5% cumplían con la definición de caso; 9 casos presentaron neumonía y 26 fiebre de Pontiac. La curva epidémica se inició el 7 de mayo, alcanzando un pico los días 14 y 15 de mayo y finalizando el día 20. El riesgo de enfermar ajustado por edad, sexo y consumo de tabaco se asoció con la duración de la estancia en el balneario (OR=118.5, 95% I.C: 18.7-750.2 y con el uso de una piscina (OR=10.5, 95% I.C: 1.3-82.6. Se detecto L. pneumophila serogrupo1 en recuentos superiores a 103 ufc/l en diversos puntos de la red de hidroterapia y en la ducha de la habitación de uno de los enfermos. El análisis por electroforesis en campos pulsados de una muestra biológica y muestras ambientales permitió la confirmación genotípica. El establecimiento se abrió al público tras realizar un tratamiento de choque y comprobar que transcurridos 15 días no se detectó L. pneumophila en las muestras ambientales.The start of seasonal activity at a spa in Guipuzcoa coincided with the detection of an associated legionnaire outbreak in 1998. This led to the closure of the premises and to the carrying out of opportune environmental and epidemiological studies. The latter included case-control study. A case was defined as a person who, either during his stay or in a period of 10 days thereafter

  8. Molecular epidemiological characteristics of norovirus gastroenteritis outbreaks in Guangdong province

    Institute of Scientific and Technical Information of China (English)

    HUI LI; LING FANG; LI RONG ZOU; CHANG WEN KE; PING HUANG; JI CHENG HUANG

    2006-01-01

    The purpose of this work is to study the molecular epidemiological characteristics of norovirus gastroenteritis outbreaks in Guangdong. During October 2003 and December 2004, fecal and anal swabs specimens collected from 13 outbreaks of non-bacterial gastroenteritis were tested for norovirus. Specimens were detected by RT-PCR and sequenced. The descriptive data were also collected. Eight in 13 outbreaks of gastroenteritis were positive for norovirus. All of 8 virus strains were identified as genogroup Ⅱ but belonged to 3 genotypes. Six strains were G Ⅱ-4 genotype. Norovirus is a major cause of outbreaks of nonbacterial gastroenteritis in Guangdong province and has a wide distribution. The illness happended from late autumn to winter. The prevalent strains were genogroup Ⅱ virus.

  9. Norovirus Polymerase Fidelity Contributes to Viral Transmission In Vivo

    DEFF Research Database (Denmark)

    Arias Esteban, Armando; Thorne, Lucy; Ghurburrun, Elsa

    2016-01-01

    Intrahost genetic diversity and replication error rates are intricately linked to RNA virus pathogenesis, with alterations in viral polymerase fidelity typically leading to attenuation during infections in vivo. We have previously shown that norovirus intrahost genetic diversity also influences v...

  10. Regeneración de brotes adventicios en hojas de guayaba (Psidium guajava L. cultivadas in vitro Adventitious shoot regeneration from in vitro cultured leaves of guava (Psidium guava L.

    Directory of Open Access Journals (Sweden)

    Trujillo Sánchez Reinaldo

    2004-12-01

    Full Text Available La regeneración de brotes adventicios es una etapa clave para la aplicación de las técnicas de ingeniería gené­tica. El presente trabajo tuvo como objetivo el desarrollo de un procedimiento para la regeneración de brotes por organogénesis a partir de hojas de microesquejes o brotes de guayaba (Psidium guajava L. cultivados in vi­tro. Para ello se estudiaron algunos de los principales factores que afectan la regeneración de brotes, tales como la concentración de reguladores del crecimiento (citoquinina, el estado fisiológico del explante y la he­rida. En todos los experimentos se utilizaron como explantes hojas de vitroplantas de guayaba de la variedad Enana Roja Cubana EEA18-40 de diferentes subcultivos. El mejor resultado se alcanzó con una concentración de 0,75 mg/L de 6-bencilaminopurina como suplemento hormonal del medio MS. Se comprobó que para las hojas provenientes de microesquejes con mayor número de subcultivo y tomadas de la parte inferior de los brotes, el potencial morfogenético disminuye significativamente (p60% y el mayor número de brotes por explante promedio (>3 se alcanzó al realizar varias heridas en forma de punteaduras en el nervio central de las hojas. Este protocolo de regeneración constituye una importante herramienta que puede ser empleada para futuros estudios de transformación genética en esta especie. Palabras clave: cultivo de tejidos, explantes de hoja, reguladores de crecimiento, organogénesis, guayaba.Adventitious regeneration is a key step in the application of genetic engineering to the breeding programs of plants. In this work a method for adventitious shoot regeneration from leaves of micropropagated guava shoots has been developed and some of main factors to affect the shoot regeneration like, concentration of plant growth regulators (citoquinine, physiological state of explants and the wound are studied. Leaves from guava in vitro cultured of variety Cuban Red Dwarf 18-40 was used

  11. Norovirus infections in preterm infants: wide variety of clinical courses

    Directory of Open Access Journals (Sweden)

    Zimmermann Kathrin

    2009-06-01

    Full Text Available Abstract Background Norovirus is an important cause of nonbacterial acute gastroenteritis in all ages. Atypical courses are described. Clinical symptoms are diarrhea, vomiting, nausea, abdominal cramps, fever and malaise. Apart from three recent short reports we describe for the first time an outbreak of norovirus in a tertiary Neonatal Intensive Care Unit. Findings The typical symptoms of norovirus infection are in part also seen in premature born infants but with a different pattern and a huge variety of clinical courses. Vomiting is not the main symptom of norovirus infection in premature infants but distended abdomen and other symptoms such as apnea, gastric remainders or sepsis like appearance. The course in premature born patients could be explained by an immunocompromised mice model. Extensive hygienic measures were necessary to control the outbreak without closing the Neonatal Intensive Care Unit. Conclusion Norovirus infection in premature infants shows an impressive pattern of a wide variety of clinical courses. Only the consequent use of different hygienic pattern can lead to elimination of norovirus.

  12. Brote de parotiditis vírica en un colegio de Bizkaia en 2006

    Directory of Open Access Journals (Sweden)

    Eduardo Millán Ortuondo

    2007-01-01

    Full Text Available Fundamento: Recientemente se han registrado brotes de parotiditis en España y en otros países desarrollados. Los motivos barajados son la baja cobertura vacunal de las poblaciones afectadas y/o la baja efectividad de las cepas vacunales empleadas. Este trabajo describe un brote de parotiditis ocurrido en Bizkaia y valora la efectividad de las cepas vacunales y la utilidad de las pruebas diagnósticas actualmente empleadas. Métodos: Se etiquetaron como casos aquéllos con clínica compatible y vínculo epidemiológico en el periodo de estudio (febrero-mayo-2006. Se recogieron muestras de sangre para estudio de IgM e IgG y de saliva para detección de RNA y genotipo. Se averiguó el estado vacunal y la cepa empleada mediante los registros del reparto vacunal. Se realizó un análisis univariante de los datos y se obtuvieron riesgos relativos según las cepas vacunales empleadas. Resultados: Se detectaron 63 casos; 52 eran alumnos del mismo colegio. El 50% tenía entre 9 y 13 años. El 88,5% de los casos del colegio estaba correctamente vacunado. La sensibilidad de la IgM fue del 9% y la de la PCR del 37%. El riesgo relativo de los alumnos vacunados con una primera dosis de cepa Rubini frente a los vacunados con cepa Jeryl-Lynn fue de 3,8 (IC95% 2,27-6,49. Conclusiones: La elevada cobertura vacunal no impide el desarrollo de brotes en lugares con un alto grado de exposición. La IgM se muestra poco sensible para el diagnóstico de parotiditis. Parece necesario replantearse las estrategias vacunales y los métodos diagnósticos actuales.

  13. Unspecified gastroenteritis illness and deaths in the elderly associated with norovirus epidemics.

    NARCIS (Netherlands)

    Asten, L. van; Siebenga, J.; Wijngaard, C. van den; Verheij, R.; Vliet, H. van; Kretzschmar, M.; Boshuizen, H.; Pelt, W. van; Koopmans, M.

    2011-01-01

    BACKGROUND: New variant strains of norovirus have emerged worldwide in recent years, evolving by mutation much like influenza viruses. These strains have been associated with a notable increase in the number of annual norovirus outbreaks. However, the impact of such increased norovirus activity on m

  14. Unspecified gastroenteritis illness and deaths in the elderly associated with norovirus epidemics

    NARCIS (Netherlands)

    Asten, van L.; Siebenga, J.; Wijngaard, van den C.; Verheij, R.; Vliet, van H.; Kretzschmar, M.; Boshuizen, H.C.; Pelt, van W.; Koopmans, M.

    2011-01-01

    Background: New variant strains of norovirus have emerged worldwide in recent years, evolving by mutation much like influenza viruses. These strains have been associated with a notable increase in the number of annual norovirus outbreaks. However, the impact of such increased norovirus activity on m

  15. Norovirus surveillance among callers to foodborne illness complaint hotline, Minnesota, USA, 2011-2013.

    Science.gov (United States)

    Saupe, Amy A; Kaehler, Dawn; Cebelinski, Elizabeth A; Nefzger, Brian; Hall, Aron J; Smith, Kirk E

    2013-08-01

    Norovirus is the leading cause of foodborne disease in the United States. During October 2011-January 2013, we conducted surveillance for norovirus infection in Minnesota among callers to a complaint-based foodborne illness hotline who reported diarrhea or vomiting. Of 241 complainants tested, 127 (52.7%) were positive for norovirus.

  16. Risk groups for clinical complications of norovirus infections: an outbreak investigation.

    NARCIS (Netherlands)

    Mattner, F; Sohr, D; Heim, A; Gastmeier, P; Vennema, H; Koopmans, M

    2006-01-01

    Norovirus infections have been described as self-limiting diseases of short duration. An investigation of a norovirus outbreak in a university hospital provided evidence for severe clinical features in patients with several underlying diseases. Clinical outcomes of norovirus infection were defined.

  17. The virucidal effects against murine norovirus and feline calicivirus F4 as surrogates for human norovirus by the different additive concentrations of ethanol-based sanitizers.

    Science.gov (United States)

    Akasaka, Tempei; Shimizu-Onda, Yuko; Hayakawa, Satoshi; Ushijima, Hiroshi

    2016-03-01

    Since human norovirus is non-cultivable, murine norovirus and feline calicivirus have been used as surrogates. In this study, the virucidal effects of ethanol-based sanitizers with different concentrations of additives (malic acid/sodium malate, glycerin-fatty acid ester) against murine norovirus and feline calicivirus F4 were examined. The ethanol-based sanitizers at pH 7 showed sufficient virucidal effects, but glycerin-fatty acid ester included in ethanol-based sanitizers at pH 4 or 6 reduced the virucidal effects against murine norovirus. The ethanol-based sanitizers containing malic acid/sodium malate inactivated feline calicivirus F4 in shorter time, but there is no difference between ethanol-based sanitizers with and without glycerin-fatty acid ester. Traditionally, feline calicivirus has been used for long time as a surrogate virus for human norovirus. However, this study suggested that murine norovirus and feline calicivirus F4 had different sensitivity with the additive components of ethanol-based sanitizers. Therefore, using feline calicivirus alone as a surrogate for human norovirus may not be sufficient to evaluate the virucidal effect of sanitizers on food-borne infections caused by human norovirus. Sanitizers having virucidal effects against at least both murine norovirus and feline calicivirus may be more suitable to inactivate human norovirus.

  18. Estimulación de cardenólidos en brotes de Digitalis purpurea L. cultivados in vitro mediante elicitores

    Directory of Open Access Journals (Sweden)

    Naivy Lisbet Pérez-Alonso

    2014-06-01

    Full Text Available Título en ingles: Stimulation of cardenolides production in Digitalis purpurea L. shoot cultures by elicitors additionTítulo corto: Elicitores en la producción de cardenólidosResumen: Digitalis purpurea L. es una de las principales fuentes de cardenólidos tales como digoxina y digitoxina. Estos fármacos son ampliamente usados en la disfunción cardíaca y para regular las arritmias del corazón. El presente trabajo se realizó con el objetivo de estudiar el efecto de tres elicitores en el cultivo de brotes de Digitalis purpurea var. Roter Berggold para incrementar la producción in vitro de cardenólidos. La elicitación es una estrategia para incrementar la producción de biomasa y metabolitos secundarios en el cultivo in vitro. Los elicitores evaluados fueron ChitoPlant (0,001; 0,01; 0,1 g.L-1; SilioPlant (0,01; 0,1; 1,0 g.L-1 y Jasmonato de metilo (60, 80 y 100 µM, descritos por primera vez para el incremento de cardenólidos. Se demostró que la elicitación es una estrategia viable para el incremento de cardenólidos en brotes de D. purpurea. El ChitoPlant®, redujo la altura sin afectación en el resto de las variables morfológicas evaluadas. Además indujo un incremento significativo en el contenido de cardenólidos. El SilioPlant® (0,01 g.L-1 no provocó afectaciones en la biomasa e incrementó significativamente la síntesis de cardenólidos en los brotes en 3,6 y 6,9 veces el contenido de digoxina y digitoxina respectivamente. La elicitación con el jasmonato de metilo provocó una reducción de la biomasa. Los contenidos de digoxina y digitoxina se incrementaron ligera y significativamente con 80 y 100 µM de jasmonato de metilo respectivamente. El mejor resultado integral se obtuvo con 0,01 g.L-1 de SilioPlant, el cual indujo la mayor producción neta de cardenólidos por frasco de cultivo (4,72 µg digoxina y 88,27 µg digitoxina. Palabras clave: chitoplant, digitoxina, digoxina, jasmonato de metilo, silioplantAbstract:

  19. Noroviruses as a Cause of Diarrhea in Immunocompromised Pediatric Hematopoietic Stem Cell and Solid Organ Transplant Recipients

    OpenAIRE

    Ye, Xunyan; Van, John N.; Munoz, Flor M.; Revell, Paula A; Kozinetz, Claudia A.; Krance, Robert A.; Atmar, Robert L.; Estes, Mary K.; Hoonmo L Koo

    2015-01-01

    Case reports describe significant norovirus gastroenteritis morbidity in immunocompromised patients. We evaluated norovirus pathogenesis in prospectively enrolled solid organ (SOT) and hematopoietic stem cell transplant (HSCT) patients with diarrhea who presented to Texas Children’s Hospital and submitted stool for enteric testing. Noroviruses were detected by real-time reverse transcription polymerase chain reaction. Clinical outcomes of norovirus diarrhea and non-norovirus diarrhea patients...

  20. Norovirus prevalence in ‘pathogen negative’ gastroenteritis in children from periurban areas in Lima, Peru

    Science.gov (United States)

    Rivera, Fulton P.; Ochoa, Theresa J.; Ruiz, Joaquim; Medina, Anicia M.; Ecker, Lucie; Mercado, Erik; Gil, Ana I.; Huicho, Luis; Lanata, Claudio F.

    2011-01-01

    Summary Norovirus was detected in 17.4% of 224 diarrhoeal samples from children younger than 24 months of age in Lima, in whom all common pathogens had been excluded (pathogen negative). Norovirus was identified more frequently in children older than 12 months of age than in younger children (34% vs 8%, P<0.001). Among norovirus-positive samples, genogroup II was the predominant group (92%). Compared with rotavirus, norovirus episodes tended to be of shorter duration and less severe. The role of norovirus as a cause of diarrhoea and the ascertainment of its severity in developing countries needs further confirmation by future epidemiological studies. PMID:21962615

  1. Viability and heat resistance of murine norovirus on bread.

    Science.gov (United States)

    Takahashi, Michiko; Takahashi, Hajime; Kuda, Takashi; Kimura, Bon

    2016-01-04

    Contaminated bread was the cause of a large-scale outbreak of norovirus disease in Japan in 2014. Contamination of seafood and uncooked food products by norovirus has been reported several times in the past; however the outbreak resulting from the contamination of bread products was unusual. A few reports on the presence of norovirus on bread products are available; however there have been no studies on the viability and heat resistance of norovirus on breads, which were investigated in this study. ce:italic>/ce:italic> strain 1 (MNV-1), a surrogate for human norovirus, was inoculated directly on 3 types of bread, but the infectivity of MNV-1 on bread samples was almost unchanged after 5days at 20°C. MNV-1 was inoculated on white bread that was subsequently heated in a toaster for a maximum of 2min. The results showed that MNV-1 remained viable if the heating period was insufficient to inactivate. In addition, bread dough contaminated with MNV-1 was baked in the oven. Our results indicated that MNV-1 may remain viable on breads if the heating duration or temperature is insufficient.

  2. Norovirus infection in Belarus: occurrence and molecular epidemiology.

    Science.gov (United States)

    Paklonskayal, Natallia Uladzimirauna; Amvrosieva, Tamara Vasil'evna; Dziadziulia, Kanstantsin Leanidavich; Baranouskaya, Natallia Mikalaeuna; Kishkurno, Elena Petrovna; Kluiko, Nina Leonidovna

    2015-03-01

    The objective of the study is to analyze molecular epidemiologic surveillance for norovirus infection in Belarus over the past five years (2009-2013). Laboratory diagnostics was carried out by RT-PCR in 684 patients. Two regions of norovirus genome, localized in RNA-polymerase and capsid protein genes, were used for phylogenetic analysis. Noroviruses were predominant causative agents in adults and second only to rotaviruses in children, they also prevailed among aetiological agents of outbreaks (66.7% of outbreaks). In 2009-2013, the major norovirus genotype was GII.4 (58.3% of all genotyped isolates). Genovariant GII.4 2006b circulated in 2009 and 2010, genovariant GII.4 2009 New Orleans - in 2010 and 2012. In addition to GII.4, genotypes GII.6 (16.6%), GII.2 (4.1%), GII.3 (2.2%), and recombinant genotypes GII.g-GII.12 and GII.g-GII.1 (10.4% and 8.3%, respectively) circulated in Belarus. The findings indicate a significant contribution of noroviruses in development of sporadic morbidity and outbreaks of acute gastroenteritis in Belarus. Outbreaks or prominent increases of sporadic morbidity were mostly due to the emergence of a new genotype, or an epidemic genovariant.

  3. Norovirus Genotypes in Hospital Settings - Differences between Nosocomial and Community-Acquired Infections

    DEFF Research Database (Denmark)

    Franck, Kristina Træholt; Nielsen, Rikke Thoft; Holzknecht, Barbara Juliane;

    2015-01-01

    BACKGROUND:  Norovirus is a major cause of gastroenteritis and hospital outbreaks, leading to substantial morbidity and direct healthcare expenses as well as indirect societal costs. The aim of the study was to estimate the proportion of nosocomial norovirus infections among inpatients tested...... positive for norovirus in Denmark, 2002-2010, and to study the distribution of norovirus genotypes among inpatients with nosocomial and community-acquired norovirus infections, respectively. METHODS:  Admission and stool sampling dates from 3656 NoV infected patients were used to estimate the proportion...... of nosocomial infections. The associations between nosocomial infection and patient age, gender, and norovirus genotype GII.4 were examined. RESULTS:  Of the 3656 inpatients, 63% were classified as having nosocomial infections. Among these 9 capsid and 8 polymerase norovirus genotypes were detected whereas...

  4. An outbreak of norovirus linked to oysters in Tasmania.

    Science.gov (United States)

    Lodo, Kerryn L; Veitch, Mark G K; Green, Michelle L

    2014-03-31

    Norovirus is the most commonly reported virus in shellfish related gastroenteritis outbreaks. In March 2013 an investigation was conducted following the receipt of reports of gastroenteritis after the consumption of oysters at private functions in Tasmania. Cases were ascertained through general practitioners, emergency departments, media releases and self-reporting. Of the 306 cases identified in Tasmania, ten faecal specimens were collected for laboratory testing and eight were positive for norovirus (GII.g). The most common symptoms were vomiting (87%), diarrhoea (85%), myalgia (82%) and fever (56%). The implicated oysters were traced to a single lease from which they were harvested and distributed locally and interstate. Nationally 525 cases were identified from Tasmania (306), Victoria (209), New South Wales (8) and Queensland (2). This report highlights the consequences of norovirus outbreaks in shellfish, even with rapid identification, trace back and removal of the implicated product from the market.

  5. Demand for care and nosocomial infection rate during the first influenza AH1N1 2009 virus outbreak at a referral hospital in Mexico City Demanda asistencial y tasa de infección nosocomial durante el primer brote de influenza AH1N1 2009 en un hospital de referencia en la Ciudad de México

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    Rogelio Pérez-Padilla

    2011-08-01

    Full Text Available OBJECTIVE: Comparison of routine hospital indicators (consults at the Emergency Room (ER and hospital admissions during the 2009 pandemic of the influenza AH1N1 virus at the national referral hospital for respiratory diseases in Mexico City. MATERIAL AND METHODS: The outbreak was from April to mid-May 2009 and two control periods were used:2009 (before and after the outbreak,and during April-May from 2007 and 2008. RESULTS: During the outbreak total consultation at the ER increased six times compared with the 2007-2008 control period and 11 times compared with the 2009 control period. Pneumonia- or influenza-related ER consultations increased 23.2 and 15.3%, respectively. The rate of nosocomial infection during the outbreak was 13.6 and that of nosocomial pneumonia was 6 per/100 hospital discharges, a two-fold and three-fold increase compared to the control periods respectively. CONCLUSIONS: During the outbreak,mean severity of admitted patients increased,with a rise in in-hospital mortality and nosocomial infections rate, including nosocomial pneumonia.OBJETIVO: Comparación de indicadores hospitalarios de rutina (consultas de urgencia, admisiones hospitalarias etc. durante la pandemia de influenzaAH1N1 2009 en un hospital de referencia para enfermedades respiratorias de la Ciudad de México. MATERIAL Y MÉTODOS: El brote se consideró de abril a la mitad de mayo de 2009 y se comparó con dos periodos control: el de 2009 (antes y después del brote, y durante abril y mayo de 2007 y 2008. RESULTADOS: Durante el brote las consultas de urgencia crecieron seis veces comparadas con el periodo control 2007-2008 y 11 veces contra el periodo control de 2009. Las consultas por neumonía o influenza incrementaron 23.2 y 15.3% comparadas contra los periodos control, respectivamente. La tasa de infección nosocomial durante el brote fue de 13.6 y la de neumonía nosocomial de 6.0 por 100 egresos hospitalarios, el doble y el triple de la documentada en los

  6. Caracterización epidemiológica de las enfermedades transmitidas por alimentos (ETA) en el periodo 2008-2012 en la ciudad de Bogotá D.C.

    OpenAIRE

    García Vesga, Adriana

    2014-01-01

    Se describen 680 brotes de enfermedades transmitidas por alimentos que afectaron a 12,171 personas en la ciudad de Bogotá DC, Colombia, en el período 2008- 2012. Se identifica la caracterización epidemiológica de los brotes año por año y en el periodo en las variables de tiempo, persona y lugar que incluyen la edad, sexo, localidad de procedencia y de notificación, los alimentos involucrados, los sitios de ocurrencia, los factores de riesgo involucrados y los agentes patógenos identificados. ...

  7. A mortality study of the last outbreak of yellow fever in Barcelona City (Spain in 1870 Estudio de la mortalidad del último brote de fiebre amarilla en la ciudad de Barcelona (España en 1870

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    Jaume Canela Soler

    2009-08-01

    Full Text Available Background: The last outbreak of yellow fever in the city of Barcelona, Spain, was caused by a ship arriving from Cuba. The objective of this study was to describe and analyze the epidemic of 1870 by using the available mortality data. Methods: The information on 1,235 deaths identified in the parochial registries was analyzed, using statistical and epidemiological procedures for epidemic outbreaks. Results: Mortality due to yellow fever was 549.7 per 100,000 inhabitants. The temporal distribution of the deaths showed two peaks at the end of September and October with the last fatalities occurring in December 1870. The distribution of the fatalities in the city's neighborhoods was unequal. In La Barceloneta, in particular, more fatalities were found in the streets adjacent to the port than in the most remote streets (r=0.83; pObjetivo: El último brote de fiebre amarilla en la ciudad de Barcelona, España, se originó a partir de un barco que venía de Cuba. El objetivo de este estudio es describir y analizar esa epidemia ocurrida en 1870, utilizando los datos disponibles de mortalidad. Métodos: La información de las 1235 defunciones identificadas en los registros parroquiales se ha analizado utilizando los procedimientos estadísticos y epidemiológicos para brotes epidémicos. Resultados: La tasa de mortalidad por fiebre amarilla fue de 549.7 por 100,000 habitantes. La distribución temporal de las muertes tenía dos modas en el final de septiembre y octubre, y los últimos muertos ocurrieron en diciembre de 1870. La distribución de las defunciones según los barrios de la ciudad fue desigual. En La Barceloneta, en particular, hubo mas muertos en las calles adyacentes al puerto que en las más lejanas (r=0,83; p<0,0001. Conclusiones: Este estudio muestra una distribución bimodal de la mortalidad por fiebre amarilla durante el brote, con un impacto alto en hombres adultos, y en el barrio de La Barceloneta.

  8. Diagnosing norovirus-associated infectious intestinal disease using viral load

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    Tam Clarence C

    2009-05-01

    Full Text Available Abstract Background Reverse transcription-polymerase chain reaction (RT-PCR is the main method for laboratory diagnosis of norovirus-associated infectious intestinal disease (IID. However, up to 16% of healthy individuals in the community, with no recent history of IID, may be RT-PCR positive; so it is unclear whether norovirus is actually the cause of illness in an IID case when they are RT-PCR positive. It is important to identify the pathogen causing illness in sporadic IID cases, for clinical management and for community based incidence studies. The aim of this study was to investigate how faecal viral load can be used to determine when norovirus is the most likely cause of illness in an IID case. Methods Real-time RT-PCR was used to determine the viral load in faecal specimens collected from 589 IID cases and 159 healthy controls, who were infected with genogroup II noroviruses. Cycle threshold (Ct values from the real-time RT-PCR were used as a proxy measure of viral load. Receiver-operating characteristic (ROC analysis was used to identify a cut-off in viral load for attributing illness to norovirus in IID cases. Results One hundred and sixty-nine IID cases and 159 controls met the inclusion criteria for the ROC analysis. The optimal Ct value cut-off for attributing IID to norovirus was 31. The same cut-off was selected when using healthy controls, or IID cases who were positive by culture for bacterial pathogens, as the reference negative group. This alternative reference negative group can be identified amongst specimens routinely received in clinical virology laboratories. Conclusion We demonstrated that ROC analysis can be used to select a cut-off for a norovirus real time RT-PCR assay, to aid clinical interpretation and diagnose when norovirus is the cause of IID. Specimens routinely received for diagnosis in clinical virology laboratories can be used to select an appropriate cut-off. Individual laboratories can use this method to

  9. Inducción y enraizamiento de brotes epicórmicos de Cordia alliodora (Ruiz Et Pavon, Oken

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    Mercedes Carranza Patiño

    2016-06-01

    Full Text Available La atractiva apariencia de la madera de Cordia alliodora (laurel, sus características físico-mecánicas, su abundante regeneración natural, captura de carbono y protección al suelo, la hacen ideal para la reforestación. No obstante, la falta de material de siembra de buena calidad para suplir la demanda media anual, convierten la propagación vegetativa en una herramienta esencial para el mejoramiento genético, y la conservación de genotipos en bancos clonales. En este sentido, se propuso establecer una metodología para la inducción y enraizamiento de brotes epicórmicos de árboles de laurel utilizando reguladores de crecimiento vegetal. Las concentraciones de citoquininas empleadas para la inducción de brotes a partir de árboles adultos fueron de: 0, 3000, 6000, 9000 mg L-1 de BAP sola y combinadas con 1000, 2000, 3000 mg L-1 de AIA, y se determinaron utilizando un Diseño Completo Aleatorizado. Las concentraciones de auxinas para el enraizamiento de los brotes fueron de 0, 1000, y 1500 mg kg-1 de ANA y AIB, mediante un DCA con arreglo factorial 3 x 3 (hormona ANA x hormona AIB. Se evaluó la inducción de brotes epicórmicos y se obtuvieron 2.67 brotes de 16.42 cm de longitud, con 6000 mg kg-1 de BAP + 2000 mg kg-1 de AIA. El porcentaje de enraizamiento fue 54%, número de raíces 1.78, longitud 2.59 con 1500 mg kg-1 de ANA + 1500 mg kg-1 de AIB. El uso de citoquininas y auxinas fue efectivo para provocar la diferenciación celular tanto en la inducción y rizogénesis de brotes epicórmicos de laurel.

  10. Epidemiology of Norovirus Infection Among Immunocompromised Patients at a Tertiary Care Research Hospital, 2010–2013

    Science.gov (United States)

    Bok, Karin; Prevots, D. Rebecca; Binder, Alison M.; Parra, Gabriel I.; Strollo, Sara; Fahle, Gary A.; Behrle-Yardley, Allison; Johnson, Jordan A.; Levenson, Eric A.; Sosnovtsev, Stanislav V.; Holland, Steven M.; Palmore, Tara N.; Green, Kim Y.

    2016-01-01

    Background. Noroviruses are a major cause of infectious gastroenteritis worldwide, and viruses can establish persistent infection in immunocompromised individuals. Risk factors and transmission in this population are not fully understood. Methods. From 2010 through 2013, we conducted a retrospective review among immunocompromised patients (n = 268) enrolled in research studies at the National Institutes of Health Clinical Center and identified a subset of norovirus-positive patients (n = 18) who provided stool specimens for norovirus genotyping analysis. Results. Norovirus genome was identified by reverse-transcription quantitative polymerase chain reaction in stools of 35 (13%) of the 268 immunocompromised patients tested, and infection prevalence was 21% (11 of 53) in persons with primary immune deficiencies and 12% (20 of 166) among persons with solid tumors or hematologic malignancies. Among 18 patients with norovirus genotyping information, norovirus GII.4 was the most prevalent genotype (14 of 18, 78%). Persistent norovirus infection (≥6 months) was documented in 8 of 18 (44%) individuals. Phylogenetic analysis of the GII.4 capsid protein sequences identified at least 5 now-displaced GII.4 variant lineages, with no evidence of their nosocomial transmission in the Clinical Center. Conclusions. Norovirus was a leading enteric pathogen identified in this immunocompromised population. Both acute and chronic norovirus infections were observed, and these were likely community-acquired. Continued investigation will further define the role of noroviruses in these patients and inform efforts toward prevention and treatment. PMID:27800529

  11. Estudio de las torres de refrigeración asociadas a brotes comunitarios de legionelosis Study of refrigeration towers associated with community outbreaks of legionellosis

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    Albert Pérez Lleonart

    2007-08-01

    Full Text Available Objetivo: Evaluar los factores de riesgo de las torres de refrigeración asociadas a un brote comunitario de legionelosis según sus características de mantenimiento y la calidad del agua. Método: Comparar los datos recogidos entre los 4 tipos de torres de refrigeración: control 1, control 2, probable y confirmada. Se han estudiado un total de 184 torres de refrigeración asociadas a 17 brotes comunitarios de legionelosis de la provincia de Barcelona durante el año 2004, de las cuales 112 son control 1, 54 control 2, 8 probables y 10 confirmadas. Resultados: Las torres confirmadas se caracterizan por: niveles elevados de conductividad, aerobios totales, dureza cálcica, sólidos totales en disolución, temperatura y turbidez; concentraciones de cloro deficientes (Objetive: To evaluate the factors of risk of the risk cooling towers associated to a community outbreak of legionellosis according to its characteristics of maintenance and the quality of the water with the purpose of improving the systems of prevention of this one disease. Method: To compare the piece of information gathered between the 4 types of cooling towers: control 1, control 2, probable and confirmed. A total of 184 cooling towers have been studied associated to 17 community outbreak of legionellosis of the province of Barcelona (Spain during the year 2004, of which 112 are control 1, 54 control 2, 8 probable and 10 confirmed. Results: The confirmed towers are characterized by: high levels of conductivity, total aerobes, calcic hardness, total solids in dissolution, temperature and turbidity; low levels of chlorine (< 2 ppm; of use hypochlorite as disinfectant in a 10%; greater degree of breach of the revision program and cleaning of the internal elements of the tower (tray, stuffed and separating of drops; degree of performance of the periodic disinfections and the cleaning of deposits of the 100%. A 47% of the investigated towers do not use the previous treatments of the

  12. Evaluación de dos ensayos de elisa IgM en la investigación de un brote de Leptospirosis

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    Manuel Céspedes

    2008-07-01

    Full Text Available Se evaluó dos pruebas rápidas para el diagnóstico serológico de leptospirosis aguda, la prueba de ELISA IgM pool (Instituto Nacional de Salud, Lima comparada con un ELISA IgM comercial (PANBIO tomando como gold standar la prueba de microaglutinación (MAT. Se examinó 24 pacientes admitidos en un hospital para la investigación de un brote de leptospirosis. Se tomó dos muestras de suero, la primera cuando fueron hospitalizados y la segunda cuando fueron a la consulta o dados de alta del hospital. Se diagnóstico leptospirosis en 19 de 24 pacientes por MAT. La prueba de ELISA IgM-pool tuvo una mejor sensibilidad para muestras agudas que el ELISA IgM comercial (73,7% vs 31,6%, valores predictivos positivos (93,3 vs 85,7% y negativos (44,4 vs 23,5% e igual especificidad (80%. En la evolución de sueros convalecientes tuvieron el mismo rendimiento, sensibilidad de 100% y especificidad de 80%. La prueba rápida ELISA IgM-pool es altamente sensible y específica, no requirere de equipo especializado y se encuentra disponible para el uso en cualquier laboratorio.

  13. Epidemiology of foodborne norovirus outbreaks, United States, 2001-2008.

    Science.gov (United States)

    Hall, Aron J; Eisenbart, Valerie G; Etingüe, Amy Lehman; Gould, L Hannah; Lopman, Ben A; Parashar, Umesh D

    2012-10-01

    Noroviruses are the leading cause of foodborne illness in the United States. To better guide interventions, we analyzed 2,922 foodborne disease outbreaks for which norovirus was the suspected or confirmed cause, which had been reported to the Foodborne Disease Outbreak Surveillance System of the Centers for Disease Control and Prevention during 2001-2008. On average, 365 foodborne norovirus outbreaks were reported annually, resulting in an estimated 10,324 illnesses, 1,247 health care provider visits, 156 hospitalizations, and 1 death. In 364 outbreaks attributed to a single commodity, leafy vegetables (33%), fruits/nuts (16%), and mollusks (13%) were implicated most commonly. Infected food handlers were the source of 53% of outbreaks and may have contributed to 82% of outbreaks. Most foods were likely contaminated during preparation and service, except for mollusks, and occasionally, produce was contaminated during production and processing. Interventions to reduce the frequency of foodborne norovirus outbreaks should focus on food workers and production of produce and shellfish.

  14. Comparison of methods for detection of norovirus in oysters

    DEFF Research Database (Denmark)

    Schultz, Anna Charlotte; Saadbye, Peter; Hoorfar, Jeffrey

    2007-01-01

    In the absence of culture methods for noroviruses, detection in foods relies on molecular techniques such as Reverse Transcription-Polymerase Chain Reaction (RT-PCR) on extracted viral RNA followed by PCR product confirmation by hybridisation and/or sequencing. However, in order to obtain...

  15. Cell Culture Assay for Human Noroviruses [response

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Tim M.; Honer Zu Bentrup, Kerstin; Orosz Coghlan, Patricia; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza A.; Nickerson, Cheryl A.

    2007-07-01

    We appreciate the comments provided by Leung et al., in response to our recently published article “In Vitro Cell Culture Infectivity Assay for Human Noroviruses” by Straub et al. (1). The specific aim of our project was to develop an in vitro cell culture infectivity assay for human noroviruses (hNoV) to enhance risk assessments when they are detected in water supplies. Reverse transcription (RT) qualitative or quantitative PCR are the primary assays for waterborne NoV monitoring. However, these assays cannot distinguish between infectious vs. non-infectious virions. When hNoV is detected in water supplies, information provided by our infectivity assay will significantly improve risk assessment models and protect human health, regardless of whether we are propagating NoV. Indeed, in vitro cell culture infectivity assays for the waterborne pathogen Cryptosporidium parvum that supplement approved fluorescent microscopy assays, do not result in amplification of the environmentally resistant hard-walled oocysts (2). However, identification of life cycle stages in cell culture provides evidence of infectious oocysts in a water supply. Nonetheless, Leung et al.’s assertion regarding the suitability of our method for the in vitro propagation of high titers of NoV is valid for the medical research community. In this case, well-characterized challenge pools of virus would be useful for developing and testing diagnostics, therapeutics, and vaccines. As further validation of our published findings, we have now optimized RT quantitative PCR to assess the level of viral production in cell culture, where we are indeed finding significant increases in viral titer. The magnitude and time course of these increases is dependent on both virus strain and multiplicity of infection. We are currently preparing a manuscript that will discuss these findings in greater detail, and the implications this may have for creating viral challenge pools

  16. Reverse genetics mediated recovery of infectious murine norovirus.

    Science.gov (United States)

    Arias, Armando; Ureña, Luis; Thorne, Lucy; Yunus, Muhammad A; Goodfellow, Ian

    2012-06-24

    Human noroviruses are responsible for most cases of human gastroenteritis (GE) worldwide and are recurrent problem in environments where close person-to-person contact cannot be avoided (1, 2). During the last few years an increase in the incidence of outbreaks in hospitals has been reported, causing significant disruptions to their operational capacity as well as large economic losses. The identification of new antiviral approaches has been limited due to the inability of human noroviruses to complete a productive infection in cell culture (3). The recent isolation of a murine norovirus (MNV), closely related to human norovirus (4) but which can be propagated in cells (5) has opened new avenues for the investigation of these pathogens (6, 7). MNV replication results in the synthesis of new positive sense genomic and subgenomic RNA molecules, the latter of which corresponds to the last third of the viral genome (Figure 1). MNV contains four different open reading frames (ORFs), of which ORF1 occupies most of the genome and encodes seven non-structural proteins (NS1-7) released from a polyprotein precursor. ORF2 and ORF3 are contained within the subgenomic RNA region and encode the capsid proteins (VP1 and VP2, respectively) (Figure 1). Recently, we have identified that additional ORF4 overlapping ORF2 but in a different reading frame is functional and encodes for a mitochondrial localised virulence factor (VF1) (8). Replication for positive sense RNA viruses, including noroviruses, takes place in the cytoplasm resulting in the synthesis of new uncapped RNA genomes. To promote viral translation, viruses exploit different strategies aimed at recruiting the cellular protein synthesis machinery (9-11). Interestingly, norovirus translation is driven by the multifunctional viral protein-primer VPg covalently linked to the 5' end of both genomic and subgenomic RNAs (12-14). This sophisticated mechanism of translation is likely to be a major factor in the limited

  17. Static and Evolving Norovirus Genotypes: Implications for Epidemiology and Immunity

    Science.gov (United States)

    Karangwa, Consolee K.; Sosnovtsev, Stanislav V.

    2017-01-01

    Noroviruses are major pathogens associated with acute gastroenteritis worldwide. Their RNA genomes are diverse, with two major genogroups (GI and GII) comprised of at least 28 genotypes associated with human disease. To elucidate mechanisms underlying norovirus diversity and evolution, we used a large-scale genomics approach to analyze human norovirus sequences. Comparison of over 2000 nearly full-length ORF2 sequences representing most of the known GI and GII genotypes infecting humans showed a limited number (≤5) of distinct intra-genotypic variants within each genotype, with the exception of GII.4. The non-GII.4 genotypes were comprised of one or more intra-genotypic variants, with each variant containing strains that differed by only a few residues over several decades (remaining “static”) and that have co-circulated with no clear epidemiologic pattern. In contrast, the GII.4 genotype presented the largest number of variants (>10) that have evolved over time with a clear pattern of periodic variant replacement. To expand our understanding of these two patterns of diversification (“static” versus “evolving”), we analyzed using NGS the nearly full-length norovirus genome in healthy individuals infected with GII.4, GII.6 or GII.17 viruses in different outbreak settings. The GII.4 viruses accumulated mutations rapidly within and between hosts, while the GII.6 and GII.17 viruses remained relatively stable, consistent with their diversification patterns. Further analysis of genetic relationships and natural history patterns identified groupings of certain genotypes into larger related clusters designated here as “immunotypes”. We propose that “immunotypes” and their evolutionary patterns influence the prevalence of a particular norovirus genotype in the human population. PMID:28103318

  18. Molecular characteristics of noroviruses genogroup I and genogroup II detected in patients with acute gastroenteritis.

    Science.gov (United States)

    Ham, Heejin; Oh, Seah; Seung, Hyunjung; Jo, Sukju

    2015-03-01

    Noroviruses are the leading cause of epidemic gastroenteritis, including foodborne outbreak, in Korea. The prevalence of human noroviruses was studied in diarrheal stool samples of patients with acute gastroenteritis by conventional duplex reverse transcription (RT)-PCR. Diarrheal stool samples were collected from 1,685 patients from the local hospitals in Seoul. The prevalence of the noroviruses was 22.8% (222/972 patients) in 2012 and 11.2% (80/713 patients) in 2013, with a total of 17.9% (302/1,685 patients). Genotyping was performed on 302 norovirus-positive stool samples to reveal 5.6% prevalence of genogroup I (GI) (17/302) and 94.4% prevalence of genogroup II (GII) (285/302). The patients with norovirus-associated acute gastroenteritis mostly showed prevalence of GII norovirus, especially GII.4 (64.6%; 195/302).

  19. Discrepancies between Antigen and Polymerase Chain Reaction Tests for the Detection of Rotavirus and Norovirus.

    Science.gov (United States)

    Kim, Hyun Soo; Kim, Jae-Seok

    2016-05-01

    We compared the results of an antigen test (ELISA) with those of polymerase chain reaction (PCR) for the detection of rotavirus and norovirus in stool specimens. Rotavirus and norovirus antigen-positive stool specimens were collected, and rotavirus and norovirus PCRs were performed on these specimens. Of the 325 rotavirus antigen-positive specimens, 200 were positive for both assays and 125 were PCR negative. Of 286 norovirus antigen-positive specimens, 51 were PCR negative. Comparison of the lower limit of detection showed that rotavirus PCR was 16 times more sensitive and norovirus PCR was over 4,000 times more sensitive than the ELISA. Discrepant results between ELISA and PCR were common, and the possibility of false-positive and false-negative results should be considered with rotavirus and norovirus assays.

  20. Outbreak of Paratyphoid Fever Among Naval Personnel in Peru (Brote de Fiebre Paratifoidea Entre Personal de la Marina Del Peru.)

    Science.gov (United States)

    1992-01-01

    urinarias. El cuadro clinico de- de origen alimentario. pendeI en gran medida de Ia cepa infectante, ]a salud general y estado inmunol6gico del huesped, yel...antecedentcs dcciaci6n con ci brote se definicron mAx diarrea. Los encuestados Ilenaron indiva-ampliamentc ique los casos hospitalizados. dualmentc los...cuestionarios en presendia dePara fines del aivilisis, se incluy6 una sub un subolicial, m6dico o investigador. Esto muestta de los casos ambulatonos

  1. RNA Populations in Immunocompromised Patients as Reservoirs for Novel Norovirus Variants

    OpenAIRE

    Vega, Everardo; Donaldson, Eric; Huynh, Jeremy; Barclay, Leslie; Lopman, Ben; Baric, Ralph; Luke F Chen; Vinjé, Jan

    2014-01-01

    Noroviruses are the leading cause of acute gastroenteritis outbreaks worldwide. The majority of norovirus outbreaks are caused by genogroup II.4 (GII.4). Novel GII.4 strains emerge every 2 to 4 years and replace older variants as the dominant norovirus. Novel variants emerge through a combination of recombination, genetic drift, and selection driven by population immunity, but the exact mechanism of how or where is not known. We detected two previously unknown novel GII.4 variants, termed GII...

  2. Modelling Estimates of Norovirus Disease in Patients with Chronic Medical Conditions

    OpenAIRE

    Thomas Verstraeten; Baoguo Jiang; John G Weil; Lin, Jennifer H.

    2016-01-01

    Background The burden of disease due to norovirus infection has been well described in the general United States population, but studies of norovirus occurrence among persons with chronic medical conditions have been limited mostly to the immunocompromised. We assessed the impact of norovirus gastroenteritis on health care utilization in US subjects with a range of chronic medical conditions. Methods We performed a retrospective cohort study using MarketScan data from July 2002 to December 20...

  3. Inactivation of norovirus and surrogates by natural phytochemicals and bioactive substances.

    Science.gov (United States)

    Ryu, Seungbo; You, Hyun Ju; Kim, Ye Won; Lee, Ariel; Ko, Gwang Pyo; Lee, Sung-Joon; Song, Moon Jung

    2015-01-01

    Human norovirus is the leading cause of sporadic gastroenteritis, which is responsible for more than 90% of all nonbacterial gastroenteritis outbreaks. While norovirus infections typically cause mild and self-limiting symptoms lasting 24-48 h, chronic persistent infections can cause severe symptoms. Although recent advances have been made in understanding the molecular characteristics of norovirus infection, no norovirus-specific antiviral drugs, or vaccines are available. Conventional intervention methods used to inactivate norovirus, such as treatment with disinfecting agents (e.g. ethanol, hypochlorite, and quaternary ammonium formulations), have shown a lack of efficacy against human norovirus when they are applied to foods and in food preparation processes. Therefore, alternative antiviral or inactivating agents such as phytochemicals have received attention as potential norovirus inhibitors due to their relatively low toxicity and lack of side effects, which allows them to be prepared as food-safe formulations. Evidence from studies using viral surrogates suggests that numerous phytochemicals and foods containing flavonoids and polyphenols have anti-norovirus activity, and future studies will be necessary to confirm the effectiveness of such compounds against human norovirus and the molecular mechanisms through which they produce antiviral effects.

  4. Mechanisms of GII.4 norovirus persistence in human populations.

    Directory of Open Access Journals (Sweden)

    Lisa C Lindesmith

    2008-02-01

    Full Text Available BACKGROUND: Noroviruses are the leading cause of viral acute gastroenteritis in humans, noted for causing epidemic outbreaks in communities, the military, cruise ships, hospitals, and assisted living communities. The evolutionary mechanisms governing the persistence and emergence of new norovirus strains in human populations are unknown. Primarily organized by sequence homology into two major human genogroups defined by multiple genoclusters, the majority of norovirus outbreaks are caused by viruses from the GII.4 genocluster, which was first recognized as the major epidemic strain in the mid-1990s. Previous studies by our laboratory and others indicate that some noroviruses readily infect individuals who carry a gene encoding a functional alpha-1,2-fucosyltransferase (FUT2 and are designated "secretor-positive" to indicate that they express ABH histo-blood group antigens (HBGAs, a highly heterogeneous group of related carbohydrates on mucosal surfaces. Individuals with defects in the FUT2 gene are termed secretor-negative, do not express the appropriate HBGA necessary for docking, and are resistant to Norwalk infection. These data argue that FUT2 and other genes encoding enzymes that regulate processing of the HBGA carbohydrates function as susceptibility alleles. However, secretor-negative individuals can be infected with other norovirus strains, and reinfection with the GII.4 strains is common in human populations. In this article, we analyze molecular mechanisms governing GII.4 epidemiology, susceptibility, and persistence in human populations. METHODS AND FINDINGS: Phylogenetic analyses of the GII.4 capsid sequences suggested an epochal evolution over the last 20 y with periods of stasis followed by rapid evolution of novel epidemic strains. The epidemic strains show a linear relationship in time, whereby serial replacements emerge from the previous cluster. Five major evolutionary clusters were identified, and representative ORF2 capsid

  5. A food-borne outbreak of gastroenteritis caused by norovirus GII in a university located in Xiamen City, China

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    Zhinan Guo

    2014-11-01

    Conclusions: The outbreak of gastroenteritis was caused mainly by bread products contaminated with norovirus GII. A food handler with an asymptomatic norovirus GII infection was the possible source of infection.

  6. Infecciones concurrentes por dos serotipos del virus dengue durante un brote en el noroeste de Perú, 2008

    OpenAIRE

    Mamani, Enrique; Laboratorio de Arbovirus, Centro Nacional de Salud Pública, Instituto Nacional de Salud. Lima, Perú. Biólogo. Magister en Microbiología.; Figueroa, Dana; Laboratorio de Arbovirus, Centro Nacional de Salud Pública, Instituto Nacional de Salud. Lima, Perú. Biólogo.; García, María Paquita; Laboratorio de Arbovirus, Centro Nacional de Salud Pública, Instituto Nacional de Salud. Lima, Perú. Tecnóloga Médico.; Garaycochea, María del Carmen; Laboratorio de Arbovirus, Centro Nacional de Salud Pública, Instituto Nacional de Salud. Lima, Perú. Biólogo.; Pozo, Edwar J.; Oficina de Epidemiología, Subregión de Salud Luciano Castilla. Sullana, Perú. Biólogo.

    2010-01-01

    Objetives. To establish the existence of concurrent infections by different dengue virus (DENV) serotypes in an outbreak in the Northwestern in Peru during 2008. Material and methods. 73 serum samples from patients with dengue were analyzed during an outbreak that occurred in Northwestern in Peru between May and June 2008. Molecular biology techniques were used to serotype the DENV, thus, firstly the viral RNA viral was extracted using Viral QIAamp RNA mini kit (Qiagen, Valencia, Californ...

  7. Response of first attack of inflammatory bowel disease requiring hospital admission to steroid therapy Respuesta al tratamiento esteroideo del primer brote de enfermedad inflamatoria intestinal que requiere ingreso hospitalario

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    M. Abu-Suboh Abadía

    2004-08-01

    Full Text Available Introduction: corticoid administration is the usual treatment of Crohn' disease (CD and ulcerative colitis (UC attacks. How-ever, information available on response rates and their predictive factors is scarce. Objective: to establish response to steroidal treatment in an homogeneous group of patients with CD or UC during their first admission to hospital. Methods: restrospective analysis of 86 patients who received systemic steroidal treatment for a severe flare-up during their first hospital admission between 1995 and 2000. Patients were treated per protocol with fluid therapy, absolute diet, IV 6-methyl-prednisolone 1 mg/kg/day, and enoxaparin at prophylactic doses. Clinical response at 30 days was considered good in case of complete remission, and poor in case of partial or absent remission. Univariate and multivariate analyses according to non-parametric statistics were performed for sociodemographic and biologic variables. Results: 45 patients with CD and 41 with UC were included. Good response rates were 64.4% for CD and 60.9% for UC. The univariate analysis showed that patients with good response have shorter evolution times and fewer previous flare-ups (p Introducción: la administración de corticoides constituye el tratamiento habitual de los brotes de enfermedad de Crohn (EC y colitis ulcerosa (CU. Sin embargo, existe poca información sobre las tasas de respuesta y los factores que puedan predecirla. Objetivo: determinar la respuesta al tratamiento esteroideo en un grupo homogéneo de pacientes de EC y CU que ingresan por primera vez en el hospital. Métodos: análisis retrospectivo de 86 pacientes que en su primer ingreso hospitalario recibieron tratamiento esteroideo sistémico por brote grave de EC o CU entre 1995 y 2000. Fueron tratados de forma protocolizada con sueroterapia, dieta absoluta, 6-metil-prednisolona 1 mg/kg/día IV y enoxaparina a dosis profilácticas. Se ha considerado la respuesta clínica a los 30 días como

  8. Detection and forecasting of oyster norovirus outbreaks: recent advances and future perspectives.

    Science.gov (United States)

    Wang, Jiao; Deng, Zhiqiang

    2012-09-01

    Norovirus is a highly infectious pathogen that is commonly found in oysters growing in fecally contaminated waters. Norovirus outbreaks can cause the closure of oyster harvesting waters and acute gastroenteritis in humans associated with consumption of contaminated raw oysters. Extensive efforts and progresses have been made in detection and forecasting of oyster norovirus outbreaks over the past decades. The main objective of this paper is to provide a literature review of methods and techniques for detecting and forecasting oyster norovirus outbreaks and thereby to identify the future directions for improving the detection and forecasting of norovirus outbreaks. It is found that (1) norovirus outbreaks display strong seasonality with the outbreak peak occurring commonly in December-March in the U.S. and April-May in the Europe; (2) norovirus outbreaks are affected by multiple environmental factors, including but not limited to precipitation, temperature, solar radiation, wind, and salinity; (3) various modeling approaches may be employed to forecast norovirus outbreaks, including Bayesian models, regression models, Artificial Neural Networks, and process-based models; and (4) diverse techniques are available for near real-time detection of norovirus outbreaks, including multiplex PCR, seminested PCR, real-time PCR, quantitative PCR, and satellite remote sensing. The findings are important to the management of oyster growing waters and to future investigations into norovirus outbreaks. It is recommended that a combined approach of sensor-assisted real time monitoring and modeling-based forecasting should be utilized for an efficient and effective detection and forecasting of norovirus outbreaks caused by consumption of contaminated oysters.

  9. Serosurvey of veterinary conference participants for evidence of zoonotic exposure to canine norovirus – study protocol

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    Mesquita João

    2012-10-01

    Full Text Available Abstract Background Noroviruses have emerged as the leading cause of outbreaks and sporadic cases of acute gastroenteritis in humans worldwide. Person-to-person contact and consumption of contaminated food are considered the most important ways of transmission of noroviruses however zoonotic transmission has been suggested. Recently, noroviruses have been found in dogs which, unlike bovine and swine noroviruses, may present a higher risk of zoonotic transfer, given to the often close contacts between humans and pet dogs in many societies across the world. The present paper describes a seroepidemiologic study aiming to provide information on the exposure level of humans to canine norovirus. Methods/Design A case–control study was designed to address the potential exposure to canine norovirus based on the presence of antibodies against canine norovirus. Sera from veterinarians (a population repeatedly in close contact with dogs will be collected in an annual Veterinary Sciences Congress in Portugal. In addition, sera from general population will be obtained and used as controls for comparative purposes. All sera will be tested for the presence of canine norovirus antibodies using a virus-like particle-based enzyme immune assay. Risk factors for canine norovirus antibodies presence in veterinarians will be investigated through the delivery of an anonymized questionnaire to the participants. Discussion The present study aims to identify seropositive individuals to canine norovirus and to assess risk profiles among veterinary professionals with occupational exposure to dogs. To our knowledge this is the first study providing information on the potential zoonotic risk of canine norovirus, thus allowing the development of preventive measures and ascertaining potential risks for Public Health resulting from contact to dogs.

  10. Brote de encefalitis de San Luis en el Área Metropolitana Buenos Aires Outbreack of St. Luis encephalitis in the Metropolitan Buenos Aires Area

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    Alfredo Seijo

    2011-06-01

    Full Text Available Se describen los hallazgos epidemiológicos y clínicos de 13 enfermos con diagnóstico de infección por virus de la encefalitis de San Luis, con transmisión entre enero y marzo de 2010, en el Area Metropolitana Buenos Aires (AMBA. Los 13 enfermos, promedio de edad 38 años, tuvieron un comienzo agudo caracterizado por hipertermia y cefalea. Entre los días dos y diez de iniciados los síntomas, 7/13 enfermos tuvieron signos y síntomas de compromiso neurológico caracterizado por meningitis sin signos encefálicos en 1/7. En 6/7 los hallazgos más frecuentes fueron: rigidez de nuca, desorientación temporoespacial, fotofobia, confusión y alteración del lenguaje. Dos resonancias magnéticas y un electroencefalograma presentaron signos de afectación de lóbulos temporales. El líquido cefalorraquídeo se caracterizó por pleocitosis con predominio de células mononucleadas, glucorraquia normal y discreto aumento de proteínas. No hubo casos fatales. En 6/13 pacientes la sospecha clínica inicial fue dengue. Por la agrupación espacial y temporal de los casos puede considerarse un brote epidémico, el primero conocido en el AMBA, ya que no se había notificado previamente la circulación epidémica del virus.We describe the epidemiological and clinical findings of 13 patients with diagnosis of infection by St. Louis encephalitis virus, transmitted between January and March 2010 in Buenos Aires Metropolitan Area (AMBA. Thirteen patients, average age 38 years, had an acute onset with hyperthermia and headache. Between days two and ten of the onset of symptoms, 7/13 patients had signs and symptoms of neurological involvement. This was characterized by meningitis without encephalic sings in 1/7 and in 6/7 the most frequent findings were: stiff neck, disorientation, photophobia, confusion and language impairment. Two MR and one EEG revealed signs of involvement of temporal lobes. The cerebrospinal fluid showed pleocytosis with predominance of

  11. Herramientas para afrontar las situaciones de crisis en un brote de gastroenteritis aguda en un colegio público Practical lessons from the risk management of an outbreak of acute gastroenteritis in a public school

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    Áurea Morillo-García

    2005-08-01

    Full Text Available En este trabajo describimos las reflexiones y conclusiones extraídas del análisis de un brote de gastroenteritis en un centro escolar, que ocasionó una crisis de salud pública. El análisis realizado tuvo como base la metodología de las matrices de "debilidades, amenazas, fortalezas y oportunidades" (DAFO. Se describe la epidemiología de los sucesos y decisiones tomadas, basadas en aspectos operativos durante una situación de crisis. Incluye la experiencia del equipo responsable del brote, las relaciones con otras entidades y la gestión de la información. Las dificultades encontradas por el equipo coordinador consistieron en el retraso de la declaración, la falta de formación de algunas entidades implicadas y el mal uso de los circuitos establecidos. Es necesario un entrenamiento específico en los actuales protocolos de manejo de crisis y fomentar la mejora continua de los circuitos de coordinación mediante la autoevaluación y actualización de conocimientos y recursos.We present our reflections on the management of an acute gastroenteritis outbreak in a public school, which caused a public health crisis, and the conclusions drawn from this experience. The methodology of strengths, weaknesses, opportunities, and threats (SWOT analysis was used. This article describes the epidemiology of the incident and the policy decisions made, but focuses on operational aspects of outbreak management. The experience of the outbreak control team, liaison with other organizations, and data management are discussed. The difficulties encountered by the outbreak team related to delay in declaring in the outbreak, lack of training in some of the entities involved, and incorrect use of the surveillance circuits. Current protocols and specific action plans for the management of outbreaks should be improved through self-evaluation and updating of resources and knowledge.

  12. Foodborne norovirus outbreak: the role of an asymptomatic food handler

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    Pintó Rosa

    2010-09-01

    Full Text Available Abstract Background In July 2005 an outbreak of acute gastroenteritis occurred on a residential summer camp in the province of Barcelona (northeast of Spain. Forty-four people were affected among residents and employees. All of them had in common a meal at lunch time on 13 July (paella, round of beef and fruit. The aim of this study was to investigate a foodborne norovirus outbreak that occurred in the residential summer camp and in which the implication of a food handler was demonstrated by laboratory tests. Methods A retrospective cohort study was designed. Personal or telephone interview was carried out to collect demographic, clinical and microbiological data of the exposed people, as well as food consumption in the suspected lunch. Food handlers of the mentioned summer camp were interviewed. Ten stool samples were requested from symptomatic exposed residents and the three food handlers that prepared the suspected food. Stools were tested for bacteries and noroviruses. Norovirus was detected using RT-PCR and sequence analysis. Attack rate, relative risks (RR and its 95% confidence intervals (CI were calculated to assess the association between food consumption and disease. Results The global attack rate of the outbreak was 55%. The main symptoms were abdominal pain (90%, nausea (85%, vomiting (70% and diarrhoea (42.5%. The disease remitted in 24-48 hours. Norovirus was detected in seven faecal samples, one of them was from an asymptomatic food handler who had not eaten the suspected food (round of beef, but cooked and served the lunch. Analysis of the two suspected foods isolated no pathogenic bacteria and detected no viruses. Molecular analysis showed that the viral strain was the same in ill patients and in the asymptomatic food handler (genotype GII.2 Melksham-like. Conclusions In outbreaks of foodborne disease, the search for viruses in affected patients and all food handlers, even in those that are asymptomatic, is essential. Health

  13. In Vitro Cell Culture Infectivity Assay for Human Noroviruses

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Tim M.; Honer Zu Bentrup, Kerstin A.; Orosz Coghlan, Patricia A.; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza; Nickerson, Cheryl A.

    2007-01-30

    Human noroviruses (NoV) cause severe, self-limiting gastroenteritis that typically lasts 24 - 48 hours. The true nature of NoV pathogenesis remains unknown due to the lack of suitable tissue culture or animal models. Here we show, for the first time, that NoV can infect and replicate in an organoid, three-dimensional (3-D) model of human small intestinal epithelium (INT-407). Cellular differentiation for this model was achieved by growing the cells in 3-D on porous collagen I-coated microcarrier beads under conditions of physiological fluid shear in rotating wall vessel bioreactors. Microscopy, PCR, and fluorescent in-situ hybridization were employed to provide evidence of NoV infection. CPE and norovirus RNA was detected at each of the five cell passages for both genogroup I and II viruses. Our results demonstrate that the highly differentiated 3-D cell culture model can support the natural growth of human noroviruses, whereas previous attempts using differentiated monolayer cultures failed.

  14. Cysteine protease activation and apoptosis in Murine norovirus infection

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    Ettayebi Khalil

    2009-09-01

    Full Text Available Abstract Background Noroviruses are the leading cause of viral gastroenteritis. Because a suitable in vitro culture system for the human virus has yet to be developed, many basic details of the infection process are unknown. Murine norovirus (MNV serves as a model system for the study of norovirus infection. Recently it was shown that infection of RAW 264.7 cells involved a novel apoptotic pathway involving survivin. Results Using a different set of approaches, the up-regulation of caspases, DNA condensation/fragmentation, and membrane blebbing, all of which are markers of apoptosis, were confirmed. Live cell imaging and activity-based protein profiling showed that activation of caspase-like proteases occurred within two hours of infection, followed by morphological changes to the cells. MNV infection in the presence of caspase inhibitors proceeded via a distinct pathway of rapid cellular necrosis and reduced viral production. Affinity purification of activity-based protein profiling targets and identification by peptide mass fingerprinting showed that the cysteine protease cathepsin B was activated early in infection, establishing this protein as an upstream activator of the intrinsic apoptotic pathway. Conclusion This work adds cathepsin B to the noncanonical programmed cell death induced by MNV, and provides data suggesting that the virus may induce apoptosis to expand the window of time for viral replication. This work also highlights the significant power of activity-based protein profiling in the study of viral pathogenesis.

  15. Intervention methods to control the transmission of noroviruses and other enteric and respiratory viruses

    NARCIS (Netherlands)

    Tuladhar, E.

    2014-01-01

    Intervention methods to control the transmission of noroviruses and other enteric and respiratory viruses Era Tuladhar Abstract Human noroviruses are the leading cause of acute and outbreak associated gastroenteritis worldwide. The outbreaks occur often in hospitals

  16. Emergence of the GII-4 Norovirus Sydney2012 strain in England, winter 2012-2013.

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    David J Allen

    Full Text Available Norovirus is the commonest cause of acute gastrointestinal disease and is the main aetiological agent of outbreaks of gastroenteritis, particularly in semi-closed environments. Norovirus infections in England typically peak between December and March each year. The most commonly detected norovirus strains belong to the genetically diverse genogroup-II genotype-4 (GII-4 genocluster and in the previous two norovirus winter seasons the majority of GII-4 strains in circulation worldwide have been genetically similar to the GII-4 strain New Orleans 1805/2009/USA. At the beginning of the 2012/13 season a genetically distinct GII-4 strain (Sydney 2012/NSW0514/2012/AU was described which emerged worldwide during the winter of 2012/13. Here we describe the emergence of norovirus strains genetically related to Sydney2012 in England during the 2012/13 season to replace NewOrleans2009 strains as the most commonly detected variant of GII-4 norovirus in England. Furthermore, we demonstrate that whilst the emergence of Sydney2012 coincided with an early peak in the number of norovirus outbreaks, there was not an overall increase in norovirus activity compared to the previous season. Finally, we show that the Sydney2012 strain is associated with distinct genetic changes compared to the NewOrleans2009 strain, and these changes may have contributed to the emergence of the Sydney2012 strain.

  17. Burden of norovirus in healthcare facilities and strategies for outbreak control

    NARCIS (Netherlands)

    A. Kambhampati; M.P.G. Koopmans D.V.M. (Marion); B.A. Lopman (Benjamin A.)

    2015-01-01

    textabstractNorovirus is the most frequently occurring cause of community-acquired acute gastroenteritis in people of all ages. It is also one of the most frequent causes of outbreaks in healthcare settings, affecting both long-term care facilities and acute care hospitals. Whereas norovirus gastroe

  18. Surface plasmon resonance biosensor for detection of feline calicivirus, a surrogate for norovirus

    Science.gov (United States)

    The human noroviruses are the most common non-bacterial cause of gastroenteritis and are responsible for as much as 50% of all gastroenteritis outbreaks worldwide. Norovirus (NoV), a single stranded RNA virus, is highly contagious with an infectious dose of less than 100 viral particles. While techn...

  19. Burden of Norovirus and Rotavirus in Children After Rotavirus Vaccine Introduction, Cochabamba, Bolivia.

    Science.gov (United States)

    McAtee, Casey L; Webman, Rachel; Gilman, Robert H; Mejia, Carolina; Bern, Caryn; Apaza, Sonia; Espetia, Susan; Pajuelo, Mónica; Saito, Mayuko; Challappa, Roxanna; Soria, Richard; Ribera, Jose P; Lozano, Daniel; Torrico, Faustino

    2016-01-01

    The effectiveness of rotavirus vaccine in the field may set the stage for a changing landscape of diarrheal illness affecting children worldwide. Norovirus and rotavirus are the two major viral enteropathogens of childhood. This study describes the prevalence of norovirus and rotavirus 2 years after widespread rotavirus vaccination in Cochabamba, Bolivia. Stool samples from hospitalized children with acute gastroenteritis (AGE) and outpatients aged 5-24 months without AGE were recruited from an urban hospital serving Bolivia's third largest city. Both viruses were genotyped, and norovirus GII.4 was further sequenced. Norovirus was found much more frequently than rotavirus. Norovirus was detected in 69/201 (34.3%) of specimens from children with AGE and 13/71 (18.3%) of those without diarrhea. Rotavirus was detected in 38/201 (18.9%) of diarrheal specimens and 3/71 (4.2%) of non-diarrheal specimens. Norovirus GII was identified in 97.8% of norovirus-positive samples; GII.4 was the most common genotype (71.4% of typed specimens). Rotavirus G3P[8] was the most prevalent rotavirus genotype (44.0% of typed specimens) and G2P[4] was second most prevalent (16.0% of typed specimens). This community is likely part of a trend toward norovirus predominance over rotavirus in children after widespread vaccination against rotavirus.

  20. Atmospheric cold plasma iactivation of norovirus surrogates and native microbiota on blueberries

    Science.gov (United States)

    Cold plasma (CP) is an emerging, novel, nonthermal technology that can be used for surface decontamination of foods. This study investigated CP technology for the nonthermal inactivation of the human norovirus surrogates, Tulane virus (TV) and Murine Norovirus (MNV), as well as for background microb...

  1. Descripción de los tres primeros brotes de gripe A (H1N1 2009 notificados en prisiones de España Description of the first three notified outbreaks of influenza A (H1N1 2009 in Spanish prisons

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    P. Gómez-Pintado

    2010-06-01

    Full Text Available Objetivos: describir los tres primeros brotes de gripe A (H1N1 2009 notificados entre julio y septiembre de 2009 en las prisiones españolas. Metodología: Se definió brote como la aparición de tres o más casos con síntomas gripales y con vínculo epidemiológico en el mismo módulo de una prisión. Los brotes son notificados mediante cuestionario específico. El análisis realizado por las variables sexo, edad, fecha de notificación, duración de los brotes, factores de riesgo y características clínicas se presenta en forma de números absolutos, porcentajes y tasas de ataque y el estudio de la difusión de la enfermedad a través de las curvas epidémicas. Resultados: Se notifican tres brotes desde las prisiones de Alcalá-Meco con 85 varones afectados, Pamplona (18 varones afectados y Jaén (12 mujeres afectadas con una tasa de ataque global que varía entre el 7,1% y el 17,9%. La duración de los brotes varía entre 8 y 35 días, y la mediana de duración de la enfermedad es de 3 días. Sólo ingresaron 4 internos que fueron dados de alta por mejoría. Los hombres son mas jóvenes (pAim: This study describes three reported outbreaks of influenza H1N1 2009 in Spanish prisons between july and september 2009. Methods: An outbreak was defined as the appearance of three or more cases with influenza symptoms and with an epidemiological link in the same module of a prison. The outbreaks were reported using a specific questionnaire. The analysis, which used variables of gender, age, date of notification, duration of outbreak, risk factors and clinical features are presented as absolute numbers, percentages and attack rates, while study of the diffusion of the illness is expressed as epidemic curves. Results: Three outbreaks were reported at the prisons of Alcala-Meco (85 affected males, Pamplona (18 affected males and Jaen (12 affected females with an overall attack rate that ranged from 7.1% to 17.9%. Duration of the outbreaks was between 8

  2. Prevalence and Molecular Genotyping of Noroviruses in Market Oysters, Mussels, and Cockles in Bangkok, Thailand.

    Science.gov (United States)

    Kittigul, Leera; Thamjaroen, Anyarat; Chiawchan, Suwat; Chavalitshewinkoon-Petmitr, Porntip; Pombubpa, Kannika; Diraphat, Pornphan

    2016-06-01

    Noroviruses are the most common cause of acute gastroenteritis associated with bivalve shellfish consumption. This study aimed to detect and characterize noroviruses in three bivalve shellfish species: oysters (Saccostrea forskali), cockles (Anadara nodifera), and mussels (Perna viridis). The virus concentration procedure (adsorption-twice elution-extraction) and a molecular method were employed to identify noroviruses in shellfish. RT-nested PCR was able to detect known norovirus GII.4 of 8.8 × 10(-2) genome copies/g of digestive tissues from oyster and cockle concentrates, whereas in mussel concentrates, the positive result was seen at 8.8 × 10(2) copies/g of digestive tissues. From August 2011 to July 2012, a total of 300 shellfish samples, including each of 100 samples from oysters, cockles, and mussels were collected and tested for noroviruses. Norovirus RNA was detected in 12.3 % of shellfish samples. Of the noroviruses, 7.7 % were of the genogroup (G) I, 2.6 % GII, and 2.0 % were mixed GI and GII. The detection rate of norovirus GI was 2.1 times higher than GII. With regards to the different shellfish species, 17 % of the oyster samples were positive, while 14.0 and 6.0 % were positive for noroviruses found in mussels and cockles, respectively. Norovirus contamination in the shellfish occurred throughout the year with the highest peak in September. Seventeen norovirus-positive PCR products were characterized upon a partial sequence analysis of the capsid gene. Based on phylogenetic analysis, five different genotypes of norovirus GI (GI.2, GI.3, GI.4, GI.5, and GI.9) and four different genotypes of GII (GII.1, GII.2, GII.3, and GII.4) were identified. These findings indicate the prevalence and distribution of noroviruses in three shellfish species. The high prevalence of noroviruses in oysters contributes to the optimization of monitoring plans to improve the preventive strategies of acute gastroenteritis.

  3. Role of noroviruses as aetiological agents of diarrhoea in developing countries.

    Science.gov (United States)

    Ayukekbong, James Ayukepi; Mesumbe, Henry Nzike; Oyero, Olufunmilayo G; Lindh, Magnus; Bergström, Tomas

    2015-08-01

    Diarrhoea is considered to be the second leading cause of death due to infections among children  developing countries may vary from those in developed countries. Noroviruses are considered to be the most common cause of acute diarrhoea in both children and adults in industrialized countries. On the other hand, there is a lack of comprehensive epidemiological evidence from developing countries that norovirus is a major cause of diarrhoea. In these regions, asymptomatic norovirus infections are very common, and similar detection rates have been observed in patients with diarrhoea and asymptomatic persons. This review summarizes the current knowledge of norovirus infection in developing countries and seeks to position infections with noroviruses among those of other enteropathogens in terms of disease burden in these regions.

  4. DISTRIBUTION OF A NEW VARIANT GII.b/HILVERSUM OF NOROVIRUS IN RETAIL MYTILUS GALLOPROVINCIALIS

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    G.M. Tantillo

    2013-02-01

    Full Text Available Norovirus is a common cause of gastroenteritis outbreaks associated with consumption of raw shellfish. The majority of norovirus infections world-wide are due to genogroup II noroviruses. Mussels (Mytilus galloprovincialis at the end of the commercial chain, the points of purchase, were sampled and screened by an hemi-nested RT-PCR specific for genogroup II noroviruses. Noroviral RNA was detected in 10% of the samples, with the lower frequency being observed in samples obtained from hypermarkets (8% rather than in samples from open-air markets and fish shops (16% and 12%, respectively, suggesting more efficient systems of purification and control being enacted by shellfish producers and suppliers of large retail chains. By sequence analysis, the strains were characterized as norovirus variant GII.b/Hilversum.

  5. Case Study: Norovirus Outbreak in Pardis Town in January 2014

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    K Naddafi

    2016-01-01

    Full Text Available Background and objectives: In the outbreak of infectious diseases, the on time epidemiological, environmental, and laboratorial investigations result in rapid diagnosis of cause and source of the outbreaks and decrease the diseases spread and public health loss. Following the outbreak of gastroenteritis in Pardis Town in January 2014, this research was conducted to identify the cause, source, and route of transmission of the outbreak. Materials and methods: First, the descriptive epidemiological study was conducted using checklist and the stool samples were prepared and analyzed. The drinking water quality in Pardis during and before the outbreak was obtained from National Environmental Health Network. The community water supply system consisting of watershed, water resources, pipelines, storage reservoirs, disinfection systems, and distribution network were inspected and sampling and detection of thermotolerant coliforms and norovirus in water samples were performed according to the Standard Methods. Results: There were 6,027 patients with symptoms of nausea, vomiting, cramps, mild diarrhea, and mild fever. The distribution of the disease in all age groups, gender, ethnicity, and location was uniform. Out of nine stool specimens, molecular testing of norovirus in six samples was positive. Hazards identified in the water supply system consisted of a water pipe fracture occurred two days before the outbreak, illegal connection of landscape irrigation system to the drinking water supply network, the use of unprotected Fellman wells as the resource of water supply, and discharge of domestic wastewater into the water resource upstream of the Fellman wells. The water samples taken from the Fellman wells had fecal contamination (11 out of 12 samples, but because of weakness and limited experience in identifying norovirus in water samples, norovirus was not detected in the raw water samples. Conclusion: This study showed that the pathogen came from a

  6. INFLUENCIA DEL USO DE REGULADORES DE CRECIMIENTO SOBRE BROTES VEGETATIVOS Y NÚMERO DE ESTRÓBILOS MASCULINOS EN Pinus pinea L. EN CHILE

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    Alejandro Venegas-González

    2016-01-01

    Full Text Available La utilización de reguladores de crecimiento o fitorreguladores, es una alternativa para aumentar la floración en la familia Pinaceae. En este estudio se analizaron los efectos de la aplicación de reguladores de crecimiento (fitorreguladores sobre brotes vegetativos y estróbilos masculinos de Pinus pinea L. Los productos seleccionados fueron: giberelina cuatro más siete (GA 4+7 , ácido naftalenacético (NAA y bencilaminopurina (BAP, distribuidos en siete tratamientos, incluido el control. Estos fitorreguladores se emplearon en una plantación de Pinus pinea de 16 años de edad ubicada en Toconey, comuna de Pencahue, región del Maule-Chile. Los tratamientos se aplicaron en cinco fechas, cada dos semanas (fin de agosto a inicio de noviembre. Al final de las aplicaciones se evaluaron las variables: estróbilos masculinos, número de brotes vegetativos y de nuevas brotes, y longitud de brotes apicales . Los principales resultados indicaron que la aplicación de 1.000 mg L -1 de GA 4+7 , fue el tratamiento que indujo la mayor floración masculina, presentando un 99,6 % más de estróbilos con respecto a las ramas testigo y también tuvo un efecto significativo en la longitud de los brotes apicales, aumentando más del doble la longitud respecto al testigo. En el número de brotes vegetativos, la aplicación de 500 mg L -1 BAP mostró diferencias significativas, obteniendo un incremento de 414,3 % con respecto al tratamiento control.

  7. Brote epidémico de denguevirus 2, genotipo Jamaica, en Bolivia

    Directory of Open Access Journals (Sweden)

    Gianella Alberto

    1998-01-01

    Full Text Available Objetivo. Confirmar la presencia de brote de dengue en la ciudad de Santa Cruz, Bolivia, así como identificar el denguevirus causal, estimar la tasa de ataque y determinar la proporción de infecciones sintomáticas. Material y métodos. En marzo de 1997 se realizó una encuesta seroepidemiológica con muestreo aleatorio en un distrito céntrico de la ciudad. Se obtuvo información sobre episodios de enfermedad aguda, antecedentes de cuadro febril reciente y muestras de sangre venosa. Se determinó la presencia de IgM antidengue con el método MAC ELISA y se procedió a la tipificación del virus con tecnología de reacción en cadena de la polimerasa. Resultados. Se detectaron anticuerpos IgM en 6.5% de los adultos (IC95% 3.4-9.6 y 5.1% de los niños (IC 95% 2.0-8.2. El virus circulante fue identificado como dengue serotipo 2, genotipo Jamaica. Menos de la mitad de los niños infectados tuvieron una infección sintomática, contra casi 90% de los adultos. Conclusiones. La tasa de ataque estimada es compatible con una epidemia de dengue en Santa Cruz. La introducción del serotipo 2 - Jamaica en el país aumenta el riesgo de dengue hemorrágico.

  8. Sensibilidad antimicrobiana y caracterización de cepas de Streptococcus pyogenes aisladas de un brote de escarlatina

    OpenAIRE

    Pedraza-Avilés Alberto González; Ortiz-Zaragoza Catalina; Mota-Vázquez Ricardo; Dickinson-Bannack Ma Eloísa; Dávila-Mendoza Rocío; Fernández-Ortega Miguel Angel

    2002-01-01

    Objetivo. Evaluar la actividad in vitro de 13 antibióticos contra 47 Streptococcus pyogenes grupo A (SGA). Determinar la presencia de genes que codifican para exotoxina pirogénica estreptocóccica A (SpeA) y serotipos con base en proteína M. Material y métodos. Estudio transversal hecho en el Centro de Salud Dr. José Castro Villagrana sobre un brote de escarlatina en el Colegio Espíritu de América, entre diciembre de 1999 y enero de 2000. El número de niños estudiados fue 137. Se extrajeron po...

  9. Peculiar brote intrahospitalario de varicela en el personal médico y paramédico

    OpenAIRE

    José Ernesto Sahagún Flores; Martín Adrian Silva Moctezuma; Alicia Pulido Ávalos; César Esteban Tovar Méndez; María de Jesús Miramontes Saldaña; Javier Eduardo García de Alba García

    2010-01-01

    Objetivo: describir las circunstancias y características que favorecieron un brote intrahospitalario de varicela en el personal médico y paramédico, así como las medidas de control implantadas. Participantes y método: se realizó un estudio de una serie de casos, a partir de la revisión clínica del caso índice. Se revisaron sus actividades dentro del hospital durante el periodo infectante y se analizaron las características que contribuyeron a la diseminación del virus. Se describen los elemen...

  10. Confirmación de aislamientos de Vibrio mimicus del brote de intoxicación alimentaria en Cuncashca, Carhuaz

    OpenAIRE

    Zamudio, María Luz

    2005-01-01

    Según el informe de la DISA Ancash, el día 12 de febrero de 2005, 48 horas después de la ocurrencia de una fiesta de carnavales celebrada en la localidad de Cuncashca, provincia de Carhuaz, lugar al que acudieron los pobladores de la zona y de comunidades aledañas, se produjo un brote de enfermedad diarreica aguda. Fueron afectadas 32 personas, de las cuales 31 eran mayores de 5 años y sólo un menor de 5 años; fueron atendidas en el Centro de Salud de Anta, Hospital de Huaraz y Hospital de...

  11. Caracteres físico-químicos del hospedero preferencial de Grapholita molesta : brotes y frutos de duraznero, Mendoza, Argentina

    OpenAIRE

    Llanos, Lorena Vanina; Marín, María Susana

    2004-01-01

    Grapholita molesta (Busck) es una plaga que tiene como principal hospedero el duraznero donde produce daños en brotes y frutos. El estudio de características físicoquímicas, en dichos órganos vegetales (pH, sólidos solubles, acidez y contenido de vitamina C) puede brindar información sobre los hábitos alimentarios de dicha plaga. Los objetivos del trabajo fueron: 1) Determinar características físico-químicas como pH, sólidos solubles, acidez y vitamina C en brotes y frutos de duraznero (c...

  12. Perspectivas de la diarrea por rotavirus en El Salvador.

    Directory of Open Access Journals (Sweden)

    Roberto Arturo Zablah

    2009-11-01

    Full Text Available Materiales y métodos: En diciembre del año 2000, un brote epidémico de gastroenteritis ocurrió en El Salvador que se asoció con numerosas hospitalizaciones y muertes de niños en todo el país. El Ministerio de Salud Pública se mostró preocupado, pues se ignoraba su etiología y las medidas de control usuales fueron ineficaces. El brote lo produjo un rotavirus, y las medidas de control fueron rediseñadas para mejorar el tratamiento con rehidratación oral e iniciar un sistema de vigilancia para conocer los agentes etiológicos de la gastroenteritis. Se colectaron datos clínicos, demográficos y también muestras de heces en niños menores de 5 años que presentaron gastroenteritis aguda. A las muestras de heces se les realizó exámenes para determinar la presencia de rotavirus, parásitos y bacterias. El sistema revigilancia se extrapoló con los datos nacionales para estimar el impacto nacional de la enfermedad por rotavirus. Resultados: La vigilancia epidemiológica entre mayo 2001 y abril 2002 demostró que el rotavirus tuvo predominio en la estación de invierno, y se asoció con la presencia de vómitos que se informaron en 27% de 12,083 consultas por diarrea. Los niños con gastroenteritis por rotavirus eran lactantes con un promedio de edad de 9 meses en comparación con las diarreas causadas por otros agentes (13 meses para bacterias y 16 meses para parásitos. Al extrapolar los datos nacionales, se estimó que el riesgo de un niño que consultaba por diarrea por rotavirus, que se hospitalizaba, y riesgo de muerte antes de los 5 años fue 1:7, 1:56, y 1:531, respectivamente. Conclusiones: El brote de gastroenteritis en niños menores de 5 años entre diciembre 2000 y febrero 2001 representó un exagerado predominio estacional de la infección por rotavirus. La actividad de vigilancia epidemiológica después del brote sugiere que el rotavirus es la causa mas frecuente de diarrea en El Salvador. Un seguimiento en la vigilancia

  13. Carlow virus, a 2002 GII.4 variant Norovirus strain from Ireland.

    LENUS (Irish Health Repository)

    Kearney, Karen

    2007-01-01

    BACKGROUND: Noroviruses are the leading cause of infectious non-bacterial gastroenteritis in Ireland (population 4 million). Due to the number of outbreaks, its massive impact on the Irish health service and its seasonality, Norovirus has gained public notoriety as The Winter Vomiting Bug. The increase in cases in Ireland in the 2002-2003 season coincided with the emergence of two new Genogroup II genotype 4 variant clusters of Norovirus worldwide. RESULTS: Little research has been done on the epidemiology or molecular biology of Norovirus strains in Ireland. In an effort to combat this discrepancy, we cloned a full length human norovirus genome as a cDNA clone (J3) which can produce full length transcripts in vitro. A polymerase mutant cDNA clone (X1), in addition to a sub genomic cDNA clone (1A) were produced for use in future work. Carlow virus (Hu\\/NoV\\/GII\\/Carlow\\/2002\\/Ire) genome is 7559 nts in length, excluding the 3-end poly A tail and represents the first Norovirus strain from Ireland to be sequenced. CONCLUSION: Carlow virus is a member of the Farmington Hills variant cluster of Genogroup II genotype 4 noroviruses.

  14. Multisite outbreak of norovirus associated with a franchise restaurant--Kent County, Michigan, May 2005.

    Science.gov (United States)

    2006-04-14

    The majority of cases of foodborne gastroenteritis in the United States are caused by noroviruses. This report summarizes an investigation by the Kent County Health Department (KCHD) in Michigan into three norovirus outbreaks and a cluster of community cases that were associated with a national submarine sandwich franchise restaurant during May 3-9, 2005. The investigation identified a potential source, a food handler who had returned to work within a few hours of having symptoms of gastrointestinal illness while he was still excreting norovirus in his stools. To prevent norovirus outbreaks, food service workers should be educated regarding norovirus transmission and control. In 2005, new guidelines for state health departments regarding norovirus containment were published by the Food and Drug Administration (FDA); guidelines for local health departments in Michigan were issued by the state's Department of Community Health and Department of Agriculture. The new guidelines for Michigan recommend that food service workers with suspected norovirus not return to work until they are asymptomatic for 48-72 hours.

  15. Enhanced detection and study of murine norovirus-1 using a more efficient microglial cell line

    Directory of Open Access Journals (Sweden)

    Lu Yuanan

    2009-11-01

    Full Text Available Abstract Background Human Noroviruses are the predominant cause of non-bacterial gastroenteritis worldwide. To facilitate prevention and control, a norovirus isolated from mice can provide a model to understand human noroviruses. To establish optimal viral infectivity conditions for murine noroviruses, several cell lines of hematopoietic lineage, including murine BV-2, RAW 264.7, and TIB, as well as human CHME-5, were tested comparatively for their sensitivity to murine norovirus-1. Results Except for CHME-5, all three murine-derived cell lines were susceptible to MNV infection. Viral infection of these cells was confirmed by RT-PCR. Using both viral plaque and replication assays, BV-2 and RAW 264.7 cells were determined to have comparable sensitivities to MNV-1 infection. Comparisons of cell growth characteristics, general laboratory handling and potential in-field applications suggest the use of BV-2 to be more advantageous. Conclusion Results obtained from these studies demonstrate that an immortalized microglial cell line can support MNV-1 replication and provides a more efficient method to detect and study murine noroviruses, facilitating future investigations using MNV-1 as a model to study, detect, and control Human Norovirus.

  16. Carlow Virus, a 2002 GII.4 variant Norovirus strain from Ireland

    Directory of Open Access Journals (Sweden)

    Menton John

    2007-06-01

    Full Text Available Abstract Background Noroviruses are the leading cause of infectious non-bacterial gastroenteritis in Ireland (population 4 million. Due to the number of outbreaks, its massive impact on the Irish health service and its seasonality, Norovirus has gained public notoriety as The Winter Vomiting Bug. The increase in cases in Ireland in the 2002–2003 season coincided with the emergence of two new Genogroup II genotype 4 variant clusters of Norovirus worldwide. Results Little research has been done on the epidemiology or molecular biology of Norovirus strains in Ireland. In an effort to combat this discrepancy, we cloned a full length human norovirus genome as a cDNA clone (J3 which can produce full length transcripts in vitro. A polymerase mutant cDNA clone (X1, in addition to a sub genomic cDNA clone (1A were produced for use in future work. Carlow virus (Hu/NoV/GII/Carlow/2002/Ire genome is 7559 nts in length, excluding the 3-end poly A tail and represents the first Norovirus strain from Ireland to be sequenced. Conclusion Carlow virus is a member of the Farmington Hills variant cluster of Genogroup II genotype 4 noroviruses.

  17. Epidemiology of foodborne Norovirus outbreaks in Catalonia, Spain

    Directory of Open Access Journals (Sweden)

    Godoy Pere

    2008-04-01

    Full Text Available Abstract Background Noroviruses are one of the principal biological agents associated with the consumption of contaminated food. The objective of this study was to analyse the size and epidemiological characteristics of foodborne outbreaks of gastroenteritis in Catalonia, a region in the northeast of Spain. Methods In all reported outbreaks of gastroenteritis associated with food consumption, faecal samples of persons affected were analysed for bacteria and viruses and selectively for parasites. Study variables included the setting, the number of people exposed, age, sex, clinical signs and hospital admissions. The study was carried out from October 2004 to October 2005. Results Of the 181 outbreaks reported during the study period, 72 were caused by Salmonella and 30 by norovirus (NoV; the incidence rates were 14.5 and 9.9 per 100,000 person-years, respectively. In 50% of the NoV outbreaks and 27% of the bacterial outbreaks (p = 0.03 the number of persons affected was ≥10; 66.7% of NoV outbreaks occurred in restaurants; no differences in the attack rates were observed according to the etiology. Hospitalizations were more common (p = 0.03 in bacterial outbreaks (8.6% than in NoV outbreaks (0.15%. Secondary cases accounted for 4% of cases in NoV outbreaks compared with 0.3% of cases in bacterial outbreaks (p Conclusion Norovirus outbreaks were larger but less frequent than bacterial outbreaks, suggesting that underreporting is greater for NoV outbreaks. Food handlers should receive training on the transmission of infections in diverse situations. Very strict control measures on handwashing and environmental disinfection should be adopted in closed or partially-closed institutions.

  18. Institutional risk factors for norovirus outbreaks in Hong Kong elderly homes: a retrospective cohort study

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    Lee Krystal CK

    2011-05-01

    Full Text Available Abstract Background Most of the institutional outbreaks of norovirus in Hong Kong occur in elderly homes, the proportion being 69% in 2006. Residents in elderly homes are a special population seriously affected by norovirus infections, it is necessary to investigate the risk factors of the norovirus outbreaks in Hong Kong elderly homes at the facility level. Methods A cohort of 748 elderly homes was followed up from January 2005 to December 2007; each elderly home was treated as one observation unit and the outcome event was the norovirus outbreak. Cox regression models were fitted to estimate the rate ratio (RR and 95% confidence interval (CI for the potential risk factors. Results A total of 276 norovirus outbreaks were confirmed during the study period; the outbreak rate was 12.2 (95% CI: 9.9-14.6 per 100 home-years; elderly homes with a larger capacity (RR = 1.4, 95% CI: 1.3-1.5 (per 30-resident increment, a higher staff-to-resident ratio (RR = 1.2, 95% CI: 1.1-1.3 (per 1/30 increment and better wheelchair accessibility (RR = 2.0, 95% CI: 1.3-3.2 were found to have an elevated norovirus outbreak rate in Hong Kong elderly homes; Elderly homes with partitions between beds had a lower rate of norovirus outbreaks (RR = 0.6, 95% CI: 0.4-0.8. Conclusions Elderly home capacity, staff-to-resident ratio and wheelchair accessibility were risk factors for norovirus outbreaks in Hong Kong elderly homes. Partitions between beds were a protective factor of norovirus outbreaks. These results should be considered in the infection control in Hong Kong elderly homes.

  19. Estudio de un brote de leptospirosis en Honduras tras el paso del huracán Mitch y potencialidad profiláctica de vax-SPIRAL®

    Directory of Open Access Journals (Sweden)

    Mariela Naranjo

    2007-12-01

    Full Text Available En Honduras, uno de los países de Centroamérica más afectados por el huracán Mitch, debido a las fuertes lluvias e inundaciones, se crearon las condiciones idóneas para el desarrollo de un brote de leptospirosis. Un grupo de especialistas cubanos realizamos un estudio a 68 pacientes con un cuadro clínico epidemiológico sospechoso de leptospirosis entre los pobladores del Departamento de Puerto Cortés, una las regiones más comprometidas. A todos los pacientes se les tomó una muestra de sangre para hemocultivo y obtención de suero. Se empleó la técnica de aglutinación microscópica (MAT para la identificación de las cepas de leptospira y para evaluar la protección conferida por vax-SPIRAL® (vacuna antileptospirósica cubana frente al reto con la cepa aislada y se verificó la prevalencia de leptospiras en los riñones e hígado. Se observó un predominio de pacientes del sexo masculino, en un grupo entre 15-49 años. Los municipios de este Departamento con un mayor número de casos fueron San Pedro Sula, La Lima y Chamelecón. Los síntomas más frecuentes fueron: fiebre, cefalea, mialgias, malestar general, entre otros. Más del 80% de los individuos manifestaron la presencia de roedores en sus viviendas y que tuvieron contacto con aguas estancadas y animales domésticos. La cepa aislada del hemocultivo positivo fue del serogrupo Icterohaemorrhagiae, muy virulento en el modelo animal empleado. Se evidenció el 100% de protección de los hámsteres inmunizados con vax-SPIRAL® y retados con la cepa de Honduras. El análisis macroscópico de los órganos de los animales inmunizados que sobrevivieron al reto al 100%, reveló la ausencia de signos característicos de la infección.

  20. Características clínicas y moleculares de un brote de influenza en dos bases militares, Tumbes- Perú, 2007

    Directory of Open Access Journals (Sweden)

    Tatiana Saldarriaga

    2008-01-01

    Full Text Available Objetivo. Describir un brote de Influenza en dos bases militares en Tumbes, Perú. Material y métodos. Se utilizó la definición de caso de síndrome gripal del Ministerio de Salud en casos con menos de cinco días de inicio de síntomas. Se tomó hisopado nasal para la prueba rápida de Influenza (PRI e hisopado faríngeo para aislamiento viral en tres líneas celulares (MDCK, VERO, LLCMK2. Para la genotipificación de Influenza B se usó un secuenciamiento parcial de la región de hemaglutinina de 898 pares de bases teniendo como base la cepa de la vacuna del 2007 (B/Florida/4/2006 y para el tipo A se analizó 958 pares de bases teniendo como referencia la cepa vacunal del 2007 (A/Brisbane/10/2007 (H3N2. Resultados. Se tomó 124 hisopados, 20 de la base militar (BM # 1 y 104 de la BM # 2. La PRI identificó a 41 casos positivos: Flu B: 27, Flu A: 02, Flu: 12, con 62% de sensibilidad y 100% de especificidad. Finalmente, 66 casos fueron confirmados por cultivo celular, 54 Flu B y 12 Flu A. Los aislamientos de Tumbes fueron genéticamente similares con la cepa B/Texas/4/ 2006 (n=34 y A/Texas/91/2007 (H3N2/ (n=7. Los síntomas más comunes fueron fiebre, cefalea, malestar general, tos, dolor de garganta, mialgias y rinorrea. Las medidas de control consistieron en el aislamiento de los casos identificados y el uso de mascarillas. Conclusiones. Se confirmó 66 casos de Influenza por cultivo celular. Los aislamientos tuvieron la mayor similitud genética con las cepas denominadas B/Texas/4/2006 y A/Texas/91/2007 (H3N2.

  1. A Gastroenteritis Outbreak Caused by Noroviruses in Greece

    Directory of Open Access Journals (Sweden)

    Yiannis Alamanos

    2011-08-01

    Full Text Available In June 2006, an outbreak alert regarding cases of acute gastroenteritis in a region in North Eastern Greece (population 100,882 inhabitants, triggered investigations to guide control measures. The outbreak started the first days of June, and peaked in July. A descriptive epidemiological study, a virological characterization of the viral agent identified from cases as well as a phylogenetic analysis was performed. From June 5 to September 3, 2006 (weeks 23–44, 1,640 cases of gastroenteritis (45.2% male and 54.8% female, aged 3 months to 89 years were reported. The overall attack rate for the period was 16.3 cases/1,000 inhabitants. About 57% of cases observed were under the age of 15 years. Αnalysis of faecal samples identified Norovirus GII strains. Fifteen different Norovirus GII strains were recorded, presenting a homology of 94.8% (86–97% to GII strains obtained from GenBank. The long duration of the outbreak suggests an important role of person-to-person transmission, while the emergence of the outbreak was possibly due to contaminated potable water, although no viruses were detected in any tested water samples. This outbreak underscores the need for a national surveillance system for acute non-bacterial gastroenteritis outbreaks.

  2. The sweet quartet: Binding of fucose to the norovirus capsid.

    Science.gov (United States)

    Koromyslova, Anna D; Leuthold, Mila M; Bowler, Matthew W; Hansman, Grant S

    2015-09-01

    Human noroviruses bind histo-blood group antigens (HBGAs) and this interaction is thought to be important for an infection. We identified two additional fucose-binding pockets (termed fucose-3/4 sites) on a genogroup II human (GII.10) norovirus-protruding (P) dimer using X-ray crystallography. Fucose-3/4 sites were located between two previously determined HBGA binding pockets (termed fucose-1/2 sites). We found that four fucose molecules were capable of binding altogether at fucose-1/2/3/4 sites on the P dimer, though the fucose molecules bound in a dose-dependent and step-wise manner. We also showed that HBGA B-trisaccharide molecules bound in a similar way at the fucose-1/2 sites. Interestingly, we discovered that the monomers of the P dimer were asymmetrical in an unliganded state and when a single B-trisaccharide molecule bound, but were symmetrical when two B-trisaccharide molecules bound. We postulate that the symmetrical dimers might favor HBGA binding interactions at fucose-1/2 sites.

  3. Characterization and control of surfactant-mediated Norovirus interactions.

    Science.gov (United States)

    Mertens, Brittany S; Velev, Orlin D

    2015-11-28

    Understanding of the colloidal interactions of Norovirus particles in aqueous medium could provide insights on the origins of the notorious stability and infectivity of these widespread viral agents. We characterized the effects of solution pH and surfactant type and concentration on the aggregation, dispersion, and disassembly of Norovirus virus-like particles (VLPs) using dynamic light scattering, electrophoretic light scattering, and transmission electron microscopy. Owing to net negative surface charge of the VLPs at neutral pH, low concentrations of cationic surfactant tend to aggregate the VLPs, whereas low concentrations of anionic surfactant tend to disperse the particles. Increasing the concentration of these surfactants beyond their critical micelle concentration leads to virus capsid disassembly and breakdown of aggregates. Non-ionic surfactants, however, had little effect on virus interactions and likely stabilized them additionally in suspension. The data were interpreted on the basis of simple models for surfactant binding and re-charging of the virus capsid. We used zeta potential data to characterize virus surface charge and interpret the mechanisms behind these demonstrated surfactant-virus interactions. The fundamental understanding and control of these interactions will aid in practical formulations for virus inactivation and removal from contaminated surfaces.

  4. Literature Reference for Noroviruses (Journal of Clinical Microbiology. 2004. 42(10): 4679–4685)

    Science.gov (United States)

    Procedures are described for analysis of clinical samples and may be adapted for of solid, particulate, aerosol, and water samples. This method is an assay for detection and quantitation of norovirus using real-time reverse transcription-PCR.

  5. 77 FR 19534 - Medical Devices; Immunology and Microbiology Devices; Classification of Norovirus Serological...

    Science.gov (United States)

    2012-04-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 866 Medical Devices; Immunology and Microbiology Devices; Classification of Norovirus Serological Reagents; Correction AGENCY: Food and Drug...

  6. Preclinical dose-ranging studies of a novel dry powder norovirus vaccine formulation.

    Science.gov (United States)

    Springer, Michael J; Ni, Yawei; Finger-Baker, Isaac; Ball, Jordan P; Hahn, Jessica; DiMarco, Ashley V; Kobs, Dean; Horne, Bobbi; Talton, James D; Cobb, Ronald R

    2016-03-14

    Norovirus is the primary cause of viral gastroenteritis in humans with multiple genotypes currently circulating worldwide. The development of a successful norovirus vaccine is contingent on its ability to induce both systemic and mucosal antibody responses against a wide range of norovirus genotypes. Norovirus virus-like particles (VLPs) are known to elicit systemic and mucosal immune responses when delivered intranasally. Incorporation of these VLPs into an intranasal powder vaccine offers the advantage of simplicity and induction of neutralizing systemic and mucosal antibodies. Nasal immunization, which provides the advantage of ease of administration and a mucosal delivery mechanism, faces the real issue of limited nasal residence time due to mucociliary clearance. Herein, we describe a novel dry powder (GelVac™) formulation of GI or GII.4 norovirus VLPs, two dominant circulating genotypes, to identify the optimal antigen dosages based on systemic and mucosal immune responses in guinea pigs. Systemic and mucosal immunogenicity of each of the VLPs was observed in a dose-dependent manner. In addition, a boosting effect was observed after the second dosing of each VLP antigen. With the GelVac™ formulation, a total antigen dose of ≥ 15 μg was determined to be the maximally immunogenic dose for both GI and GII.4 norovirus VLPs based on evaluation for 56 days. Taken together, these results indicate that norovirus VLPs could be used as potential vaccine candidates without using an immunostimulatory adjuvant and provide a basis for the development of a GelVac™ bivalent GI/GII.4 norovirus VLP vaccine.

  7. Frequency of Adenoviruses, Rotaviruses and Noroviruses Among Diarrhea Samples Collected From Infants of Zabol, Southeastern Iran

    OpenAIRE

    Sharifi-Rad, Javad; Hoseini Alfatemi, Seyedeh Mahsan; Sharifi-Rad, Mehdi; Miri, Abdolhossein

    2015-01-01

    Background: Viruses are one of the major reasons of gastrointestinal disease worldwide, and commonly infect children less than five years of age in developing countries. Objectives: The current study aimed to determine the frequency of adenoviruses, rotaviruses and noroviruses among diarrhea samples collected from infants of Zabol, south-east of Iran. This study is the first investigation of adenoviruses, rotaviruses and noroviruses among diarrhea samples in Zabol. Patients and Methods: In th...

  8. Norovirus-related chronic diarrhea in a patient treated with alemtuzumab for chronic lymphocytic leukemia

    OpenAIRE

    Ronchetti, Anne-Marie; Henry, Benoit; Ambert-Balay, Katia; Pothier, Pierre; Decroocq, Justine; Leblond, Véronique; Roos-Weil, Damien

    2014-01-01

    Background Norovirus infection is increasingly recognized as an important cause of persistent gastroenteritis in immunocompromised hosts and can be a potential cause of morbidity in these populations. Case presentation Here, we report a case of norovirus-related chronic diarrhea occurring in a 62-year-old immunocompromised patient treated with alemtuzumab for chronic lymphocytic leukemia. Despite different therapeutic strategies including tapering of immunosuppressive therapy and immunoglobul...

  9. Epidemiology of Norovirus Infection Among Immunocompromised Patients at a Tertiary Care Research Hospital, 2010–2013

    OpenAIRE

    Bok, Karin; Prevots, D. Rebecca; Binder, Alison M.; Parra, Gabriel I.; Strollo, Sara; Fahle, Gary A.; Behrle-Yardley, Allison; Johnson, Jordan A.; Levenson, Eric A.; Sosnovtsev, Stanislav V.; Holland, Steven M.; Palmore, Tara N.; Green, Kim Y.

    2016-01-01

    Background.  Noroviruses are a major cause of infectious gastroenteritis worldwide, and viruses can establish persistent infection in immunocompromised individuals. Risk factors and transmission in this population are not fully understood. Methods.  From 2010 through 2013, we conducted a retrospective review among immunocompromised patients (n = 268) enrolled in research studies at the National Institutes of Health Clinical Center and identified a subset of norovirus-positive patients (n = 18...

  10. The Vast and Varied Global Burden of Norovirus: Prospects for Prevention and Control.

    Science.gov (United States)

    Lopman, Benjamin A; Steele, Duncan; Kirkwood, Carl D; Parashar, Umesh D

    2016-04-01

    Globally, norovirus is associated with approximately one-fifth of all diarrhea cases, with similar prevalence in both children and adults, and is estimated to cause over 200,000 deaths annually in developing countries. Norovirus is an important pathogen in a number of high-priority domains: it is the most common cause of diarrheal episodes globally, the principal cause of foodborne disease outbreaks in the United States, a key health care-acquired infection, a common cause of travel-associated diarrhea, and a bane for deployed military troops. Partly as a result of this ubiquity and burden across a range of different populations, identifying target groups and strategies for intervention has been challenging. And, on top of the breadth of this public health problem, there remain important gaps in scientific knowledge regarding norovirus, especially with respect to disease in low-income settings. Many pathogens can cause acute gastroenteritis. Historically, rotavirus was the most common cause of severe disease in young children globally. Now, vaccines are available for rotavirus and are universally recommended by the World Health Organization. In countries with effective rotavirus vaccination programs, disease due to that pathogen has decreased markedly, but norovirus persists and is now the most common cause of pediatric gastroenteritis requiring medical attention. However, the data supporting the precise role of norovirus in low- and middle-income settings are sparse. With vaccines in the pipeline, addressing these and other important knowledge gaps is increasingly pressing. We assembled an expert group to assess the evidence for the global burden of norovirus and to consider the prospects for norovirus vaccine development. The group assessed the evidence in the areas of burden of disease, epidemiology, diagnostics, disease attribution, acquired immunity, and innate susceptibility, and the group considered how to bring norovirus vaccines from their current state of

  11. Human norovirus binding to select bacteria representative of the human gut microbiota

    Science.gov (United States)

    Almand, Erin A.; Outlaw, Janie; Jaykus, Lee-Ann

    2017-01-01

    Recent reports describe the ability of select bacterial strains to bind human norovirus, although the specificity of such interactions is unknown. The purpose of this work was to determine if a select group of bacterial species representative of human gut microbiota bind to human norovirus, and if so, to characterize the intensity and location of that binding. The bacteria screened included naturally occurring strains isolated from human stool (Klebsiella spp., Citrobacter spp., Bacillus spp., Enterococcus faecium and Hafnia alvei) and select reference strains (Staphylococcus aureus and Enterobacter cloacae). Binding in PBS was evaluated to three human norovirus strains (GII.4 New Orleans 2009 and Sydney 2012, GI.6) and two surrogate viruses (Tulane virus and Turnip Crinkle Virus (TCV)) using a suspension assay format linked to RT-qPCR for quantification. The impact of different overnight culture media prior to washing on binding efficiency in PBS was also evaluated, and binding was visualized using transmission electron microscopy. All bacteria tested bound the representative human norovirus strains with high efficiency (90% binding efficiency) (p>0.05); there was selective binding for Tulane virus and no binding observed for TCV. Binding efficiency was highest when bacteria were cultured in minimal media (90% bound), but notably decreased when cultured in enriched media (1–3 log10 unbound or 0.01 –structures, without apparent localization. The findings reported here further elucidate and inform the dynamics between human noroviruses and enteric bacteria with implications for norovirus pathogenesis. PMID:28257478

  12. Current Status of Norovirus Infections in Children in Sub-Saharan Africa

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    Samuel Munalula Munjita

    2015-01-01

    Full Text Available Noroviruses are a leading cause of acute sporadic gastroenteritis worldwide. In Sub-Saharan Africa, information regarding norovirus infections in children is scarce. A systematic review of studies performed between 1993 and June 2015 was conducted to establish the genotypic distribution and prevalence of norovirus infections in children (≤17 in Sub-Saharan Africa. Analysis of data from 19 studies involving 8,399 samples from children with symptomatic and nonsymptomatic gastroenteritis revealed prevalence of 12.6% (range 4.6% to 32.4%. The prevalence of norovirus infections was higher in symptomatic children (14.2% than asymptomatic children (9.2%. Genogroup II (GII was the most prevalent genogroup accounting for 76.4% of all the reported norovirus infections. The rest of the infections were GI (21.7% and GI/GII (1.9%. The most common genotypes were GII.4 (65.2%, GI.7 (33.3%, and GI.3 (21.3%. These statistics were calculated from studies carried out in 12 out of 48 Sub-Saharan African countries. Therefore, more studies involving several countries are required to determine fully the epidemiology of noroviruses and their contribution to childhood diarrhoea in Sub-Saharan Africa.

  13. Natural infection of murine norovirus in conventional and specific pathogen-free (SPF laboratory mice

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    Takeo eOhsugi

    2013-01-01

    Full Text Available Noroviruses cause most cases of acute viral gastroenteritis worldwide. The lack of a cell culture infection model for human norovirus necessitates the use of molecular methods and/or viral surrogate models amenable to cell culture to predict norovirus inactivation. Murine norovirus (MNV may be used to construct a small animal model for studying the biology and pathogenesis of noroviruses because MNV is the only norovirus that replicates in cell culture and a small animal model. However, recent studies have shown that natural MNV infection is widespread in laboratory mouse colonies. We investigated MNV infection in both conventional and specific pathogen-free (SPF genetically modified mice from Japan and the US, and commercial mice from several animal breeders in Japan, using serological and molecular techniques. MNV antibodies were detected in 67.3% of conventional mice and 39.1% of SPF mice from Japan and 62.5% of conventional mice from the US. MNV antibodies were also found in 20% of commercial SPF C57BL/6 mice from one of three breeders. Partial gene amplification of fecal isolates from infected animals showed that the isolates were homologous to reported MNV sequences. These results suggest that both conventional and SPF laboratory mice, including commercial mice, are widely infected with MNV, which might require considerable attention as an animal model of human disease.

  14. Prevalence of Rotavirus, Adenovirus, Norovirus, and Astrovirus Infections and Coinfections among Hospitalized Children in Northern France▿

    Science.gov (United States)

    Tran, Adissa; Talmud, Déborah; Lejeune, Benoît; Jovenin, Nicolas; Renois, Fanny; Payan, Christopher; Leveque, Nicolas; Andreoletti, Laurent

    2010-01-01

    From January to December 2007, 973 stool specimens were prospectively collected from children hospitalized for gastroenteritis signs or from neonates and premature cases who were born in two French hospital settings in the north of France. They were tested by rapid enzyme immunoassay (EIA) analyses for rotavirus and adenovirus and by two commercially available ELISA tests for the detection of norovirus and astrovirus. The overall rates of prevalence for rotavirus, norovirus, adenovirus, and astrovirus were 21, 13, 5, and 1.8%, respectively, and they did not significantly differ between the two hospital settings (P = 0.12). Mixed virus infections were detected in 32 (3.3%) of the 973 study children and were associated with norovirus in 21 (66%) infants, including 5 premature cases. From fall to spring, norovirus infections accounted for 52% of documented gastroenteritidis viral infections at a time when rotavirus was epidemic, resulting in mixed norovirus and rotavirus gastrointestinal tract infections. Of the 367 documented viral gastroenteritis cases, 15 (4.1%) were identified as nosocomial infections, 5 of which occurred in premature cases. These findings highlight the need to implement norovirus and astrovirus ELISA detection assays in association with rapid EIA rotavirus and adenovirus detection assays for the clinical diagnosis and the nosocomial prevention of gastroenteritis viral infections in pediatric departments. PMID:20305010

  15. The adaptive value of shoot differentiation in deciduous trees and its evolutionary relevance Valor adaptativo de la diferenciación de brotes en árboles deciduos y su relevancia evolutiva

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    Veit M. Dörken

    2009-12-01

    Full Text Available Pronounced long shoot/short shoot differentiation is typical for deciduous angiosperm trees. It also occurs in a number of gymnosperms and very few evergreen angiosperm trees. The study of 719 angiosperm tree species (602 deciduous and 117 evergreen species demonstrated that the deciduous condition is nearly always associated with shoot differentiation. Detailed measurements in 38 angiosperms showed that the leaf area of an entire short shoot equals the leaf area of a single long shoot leaf of the same species and individual. In the few cases where the leaf area of the short shoot is slightly larger than that of a single long-shoot leaf, the short shoot leaves shade each other and the projection of the short shoot equals the area of a single long shoot leaf. Calculations of the stem biomass needed to expose a given assimilatory surface show two interesting aspects. First, the stem biomass (dry weight to expose leaf surface is about 10 times less in short shoots than in long shoots. Second, this biomass in long shoots and short shoots appears to be species independent. Regarding shoot structure efficiency, leaf size and shape do not matter. Some evergreen species resemble in all parameters more to deciduous species than to typical evergreen species. Phytogeographical data as well as morphological data suggest that these atypical evergreen species are derived from deciduous ancestors. As measured parameters differ markedly between all gymnosperms, except Ginkgo, and angiosperms, we suppose that the evolutionary pathway leading to shoot differentiation was different for gymnosperms and angiosperms.En Angiospermas arbóreas deciduas, es común encontrar un alto grado de diferenciación entre brotes largos y brotes cortos. También se presenta esta característica en un número de gimnospermas y en muy pocas angiospermas arbóreas siempreverdes. El estudio de 719 especies de angiospermas arbóreas (602 deciduas y 117 siempreverdes demostró que la

  16. Immunogenetic mechanisms driving norovirus GII.4 antigenic variation.

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    Lisa C Lindesmith

    Full Text Available Noroviruses are the principal cause of epidemic gastroenteritis worldwide with GII.4 strains accounting for 80% of infections. The major capsid protein of GII.4 strains is evolving rapidly, resulting in new epidemic strains with altered antigenic potentials. To test if antigenic drift may contribute to GII.4 persistence, human memory B cells were immortalized and the resulting human monoclonal antibodies (mAbs characterized for reactivity to a panel of time-ordered GII.4 virus-like particles (VLPs. Reflecting the complex exposure history of the volunteer, human anti-GII.4 mAbs grouped into three VLP reactivity patterns; ancestral (1987-1997, contemporary (2004-2009, and broad (1987-2009. NVB 114 reacted exclusively to the earliest GII.4 VLPs by EIA and blockade. NVB 97 specifically bound and blocked only contemporary GII.4 VLPs, while NBV 111 and 43.9 exclusively reacted with and blocked variants of the GII.4.2006 Minerva strain. Three mAbs had broad GII.4 reactivity. Two, NVB 37.10 and 61.3, also detected other genogroup II VLPs by EIA but did not block any VLP interactions with carbohydrate ligands. NVB 71.4 cross-neutralized the panel of time-ordered GII.4 VLPs, as measured by VLP-carbohydrate blockade assays. Using mutant VLPs designed to alter predicted antigenic epitopes, two evolving, GII.4-specific, blockade epitopes were mapped. Amino acids 294-298 and 368-372 were required for binding NVB 114, 111 and 43.9 mAbs. Amino acids 393-395 were essential for binding NVB 97, supporting earlier correlations between antibody blockade escape and carbohydrate binding variation. These data inform VLP vaccine design, provide a strategy for expanding the cross-blockade potential of chimeric VLP vaccines, and identify an antibody with broadly neutralizing therapeutic potential for the treatment of human disease. Moreover, these data support the hypothesis that GII.4 norovirus evolution is heavily influenced by antigenic variation of neutralizing

  17. Brote de encefalitis de San Luis en el Área Metropolitana Buenos Aires

    OpenAIRE

    2011-01-01

    Se describen los hallazgos epidemiológicos y clínicos de 13 enfermos con diagnóstico de infección por virus de la encefalitis de San Luis, con transmisión entre enero y marzo de 2010, en el Area Metropolitana Buenos Aires (AMBA). Los 13 enfermos, promedio de edad 38 años, tuvieron un comienzo agudo caracterizado por hipertermia y cefalea. Entre los días dos y diez de iniciados los síntomas, 7/13 enfermos tuvieron signos y síntomas de compromiso neurológico caracterizado por meningitis sin sig...

  18. Galler-induced reduction of shoot growth and fruit production in the shrub Colliguaja integerrima (Euphorbiaceae Insectos cecidómidos reducen el crecimiento de brotes y la producción de frutos en el arbusto Colliguaja integerrima (Euphorbiaceae

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    WILFREDO L. GONZÁLES

    2005-09-01

    huevos depositados por el cecidómido y el número de cecidias entre arbustos. La producción de frutos se relacionó inversamente con el número de cecidias, pero no presentó asociación significativa con la altura del arbusto, su cobertura ni con el número de brotes. Brotes sin cecidias fueron más largos que los con cecidias. El tratamiento químico produjo un efecto positivo retrasado sobre la reproducción de la planta. Una vez transcurridos 24 meses de iniciado el experimento químico, el número de frutos fue mayor en las ramas experimentales que en las ramas control (con cecidias. De igual manera, la remoción mecánica de cecidias aumentó la producción de frutos en comparación a las ramas control en la siguiente estación reproductiva del arbusto. Estos resultados indican que el cecidómido reduce el crecimiento de los brotes y tiene un efecto negativo retardado sobre la producción de frutos de C. integerrima. Como la probabilidad de detectar cecidias nuevas fue mayor en los arbustos previamente infectados, es posible que el proceso de reinfección de cuenta de los efectos negativos acumulativos del insecto sobre el desempeño de la planta

  19. Recovery and Disinfection of Two Human Norovirus Surrogates, Feline Calicivirus and Murine Norovirus, from Hard Nonporous and Soft Porous Surfaces.

    Science.gov (United States)

    Yeargin, Thomas; Fraser, Angela; Huang, Guohui; Jiang, Xiuping

    2015-10-01

    Human norovirus is a leading cause of foodborne disease and can be transmitted through many routes, including environmental exposure to fomites. In this study, both the recovery and inactivation of two human norovirus surrogates, feline calicivirus (FCV) and murine norovirus (MNV), on hard nonporous surfaces (glass) and soft porous surfaces (polyester and cotton) were evaluated by both plaque assay and reverse transcription quantitative PCR method. Two disinfectants, sodium hypochlorite (8.25%) and accelerated hydrogen peroxide (AHP, at 4.25%) were evaluated for disinfection efficacy. Five coupons per surface type were used to evaluate the recovery of FCV and MNV by sonication and stomaching and the disinfection of each surface type by using 5 ml of disinfectant for a contact time of 5 min. FCV at an initial titer of ca. 7 log PFU/ml was recovered from glass, cotton, and polyester at 6.2, 5.4, and 3.8 log PFU/ml, respectively, compared with 5.5, 5.2, and 4.1 log PFU/ml, respectively, for MNV with an initial titer of ca. 6 log PFU/ml. The use of sodium hypochlorite (5,000 ppm) was able to inactivate both FCV and MNV (3.1 to 5.5 log PFU/ml) below the limit of detection on all three surface types. AHP (2,656 ppm) inactivated FCV (3.1 to 5.5 log PFU/ml) below the limit of detection for all three surface types but achieved minimal inactivation of MNV (0.17 to 1.37 log PFU/ml). Reduction of viral RNA by sodium hypochlorite corresponded to 2.72 to 4.06 log reduction for FCV and 2.07 to 3.04 log reduction for MNV on all three surface types. Reduction of viral RNA by AHP corresponded to 1.89 to 3.4 log reduction for FCV and 0.54 to 0.85 log reduction for MNV. Our results clearly indicate that both virus and surface types significantly influence recovery efficiency and disinfection efficacy. Based on the performance of our proposed testing method, an improvement in virus recovery will be needed to effectively validate virus disinfection of soft porous surfaces.

  20. Llama nanoantibodies with therapeutic potential against human norovirus diarrhea.

    Science.gov (United States)

    Garaicoechea, Lorena; Aguilar, Andrea; Parra, Gabriel I; Bok, Marina; Sosnovtsev, Stanislav V; Canziani, Gabriela; Green, Kim Y; Bok, Karin; Parreño, Viviana

    2015-01-01

    Noroviruses are a major cause of acute gastroenteritis, but no vaccines or therapeutic drugs are available. Llama-derived single chain antibody fragments (also called VHH) are small, recombinant monoclonal antibodies of 15 kDa with several advantages over conventional antibodies. The aim of this study was to generate recombinant monoclonal VHH specific for the two major norovirus (NoV) genogroups (GI and GII) in order to investigate their potential as immunotherapy for the treatment of NoV diarrhea. To accomplish this objective, two llamas were immunized with either GI.1 (Norwalk-1968) or GII.4 (MD2004) VLPs. After immunization, peripheral blood lymphocytes were collected and used to generate two VHH libraries. Using phage display technology, 10 VHH clones specific for GI.1, and 8 specific for GII.4 were selected for further characterization. All VHH recognized conformational epitopes in the P domain of the immunizing VP1 capsid protein, with the exception of one GII.4 VHH that recognized a linear P domain epitope. The GI.1 VHHs were highly specific for the immunizing GI.1 genotype, with only one VHH cross-reacting with GI.3 genotype. The GII.4 VHHs reacted with the immunizing GII.4 strain and showed a varying reactivity profile among different GII genotypes. One VHH specific for GI.1 and three specific for GII.4 could block the binding of homologous VLPs to synthetic HBGA carbohydrates, saliva, and pig gastric mucin, and in addition, could inhibit the hemagglutination of red blood cells by homologous VLPs. The ability of Nov-specific VHHs to perform well in these surrogate neutralization assays supports their further development as immunotherapy for NoV treatment and immunoprophylaxis.

  1. Interactions between Human Norovirus Surrogates and Acanthamoeba spp.

    Science.gov (United States)

    Hsueh, Tun-Yun; Gibson, Kristen E

    2015-06-15

    Human noroviruses (HuNoVs) are the most common cause of food-borne disease outbreaks, as well as virus-related waterborne disease outbreaks in the United States. Here, we hypothesize that common free-living amoebae (FLA)-ubiquitous in the environment, known to interact with pathogens, and frequently isolated from water and fresh produce-could potentially act as reservoirs of HuNoV and facilitate the environmental transmission of HuNoVs. To investigate FLA as reservoirs for HuNoV, the interactions between two Acanthamoeba species, A. castellanii and A. polyphaga, as well as two HuNoV surrogates, murine norovirus type 1 (MNV-1) and feline calicivirus (FCV), were evaluated. The results showed that after 1 h of amoeba-virus incubation at 25°C, 490 and 337 PFU of MNV-1/ml were recovered from A. castellanii and A. polyphaga, respectively, while only few or no FCVs were detected. In addition, prolonged interaction of MNV-1 with amoebae was investigated for a period of 8 days, and MNV-1 was demonstrated to remain stable at around 200 PFU/ml from day 2 to day 8 after virus inoculation in A. castellanii. Moreover, after a complete amoeba life cycle (i.e., encystment and excystment), infectious viruses could still be detected. To determine the location of virus associated with amoebae, immunofluorescence experiments were performed and showed MNV-1 transitioning from the amoeba surface to inside the amoeba over a 24-h period. These results are significant to the understanding of how HuNoVs may interact with other microorganisms in the environment in order to aid in its persistence and survival, as well as potential transmission in water and to vulnerable food products such as fresh produce.

  2. Inactivation of murine norovirus by chemical biocides on stainless steel

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    Steinmann Jörg

    2009-07-01

    Full Text Available Abstract Background Human norovirus (NoV causes more than 80% of nonbacterial gastroenteritis in Europe and the United States. NoV transmission via contaminated surfaces may be significant for the spread of viruses. Therefore, measures for prevention and control, such as surface disinfection, are necessary to interrupt the dissemination of human NoV. Murine norovirus (MNV as a surrogate for human NoV was used to study the efficacy of active ingredients of chemical disinfectants for virus inactivation on inanimate surfaces. Methods The inactivating properties of different chemical biocides were tested in a quantitative carrier test with stainless steel discs without mechanical action. Vacuum-dried MNV was exposed to different concentrations of alcohols, peracetic acid (PAA or glutaraldehyde (GDA for 5 minutes exposure time. Detection of residual virus was determined by endpoint-titration on RAW 264.7 cells. Results PAA [1000 ppm], GDA [2500 ppm], ethanol [50% (v/v] and 1-propanol [30% (v/v] were able to inactivate MNV under clean conditions (0.03% BSA on the carriers by ≥ 4 log10 within 5 minutes exposure time, whereas 2-propanol showed a reduced effectiveness even at 60% (v/v. Furthermore, there were no significant differences in virus reduction whatever interfering substances were used. When testing with ethanol, 1- and 2-propanol, results under clean conditions were nearly the same as in the presence of dirty conditions (0.3% BSA plus 0.3% erythrocytes. Conclusion Products based upon PAA, GDA, ethanol and 1-propanol should be used for NoV inactivation on inanimate surfaces. Our data provide valuable information for the development of strategies to control NoV transmission via surfaces.

  3. Challenges of culturing human norovirus in three-dimensional organoid intestinal cell culture models.

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    Efstathia Papafragkou

    Full Text Available Human noroviruses are the most common cause of acute gastroenteritis worldwide. Recently, cell culture systems have been described using either human embryonic intestinal epithelial cells (Int-407 or human epithelial colorectal adenocarcinoma cells (Caco-2 growing on collagen-I porous micro carrier beads in a rotating bioreactor under conditions of physiological fluid shear. Here, we describe the efforts from two independent laboratories to implement this three dimensional (3D cell culture system for the replication of norovirus. Int-407 and Caco-2 were grown in a rotating bioreactor for up to 28 days. Prior to infection, cells were screened for the presence of microvilli by electron microscopy and stained for junction proteins (zonula occludens-1, claudin-1, and β-catenin. Differentiated 3D cells were transferred to 24-well plates and infected with bacteria-free filtrates of various norovirus genotypes (GI.1, GI.3, GI.8, GII.2, GII.4, GII.7, and GII.8. At 12 h, 24 h, and 48 h post inoculation, viral RNA from both cells and supernatants were collected and analyzed for norovirus RNA by real-time reverse transcription PCR. Despite observations of high expression of junction proteins and microvilli development in stained thin sections, our data suggest no significant increase in viral titer based on norovirus RNA copy number during the first 48 h after inoculation for the different samples and virus culture conditions tested. Our combined efforts demonstrate that 3D cell culture models using Int-407 or Caco-2 cells do not support norovirus replication and highlight the complexity and difficulty of developing a reproducible in vitro cell culture system for human norovirus.

  4. Structure-Guided Design and Optimization of Dipeptidyl Inhibitors of Norovirus 3CL Protease. Structure-Activity Relationships and Biochemical, X-ray Crystallographic, Cell-Based, and In Vivo Studies

    Science.gov (United States)

    Kankanamalage, Anushka C. Galasiti; Kim, Yunjeong; Weerawarna, Pathum M.; Uy, Roxanne Adeline Z.; Damalanka, Vishnu C.; Mandadapu, Sivakoteswara Rao; Alliston, Kevin R.; Mehzabeen, Nurjahan; Battaile, Kevin P.; Lovell, Scott; Chang, Kyeong-Ok; Groutas, William C.

    2015-01-01

    Norovirus infection constitutes the primary cause of acute viral gastroenteritis. There are currently no vaccines or norovirus-specific antiviral therapeutics available for the management of norovirus infection. Norovirus 3C-like protease is essential for viral replication, consequently, inhibition of this enzyme is a fruitful avenue of investigation that may lead to the emergence of anti-norovirus therapeutics. We describe herein the optimization of dipeptidyl inhibitors of norovirus 3C-like protease using iterative SAR, X-ray crystallographic, and enzyme and cell-based studies. We also demonstrate herein in vivo efficacy of an inhibitor using the murine model of norovirus infection. PMID:25761614

  5. Formación de biopelículas por Vibrio cholerae

    OpenAIRE

    2011-01-01

    La bacteria Vibrio cholerae es un habitante natural de los ambientes marinos y el agente causal del cólera. En lugares donde la enfermedad es endémica ocurren brotes estacionales que pueden propagarse al resto del mundo. La capacidad de V. cholerae de causar epidemias está unida a su habilidad para sobrevivir por largos períodos de tiempo en los ambientes acuáticos. Se ha propuesto que las biopelículas (comunidades microbianas unidas a una superficie, embebidas en una matriz exopolimérica) so...

  6. Patogénesis de las infecciones producidas por rickettsias en las Américas

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    Gustavo Valbuena

    2010-04-01

    Full Text Available Colombia fue el segundo país en reportar rickettsiosis en Latino América (en el año de 1.937; el primero fue Brasil. Estos primeros casos reportados correspondieron a un brote de fiebre de las Montañas Rocosas que ocurrió en la localidad de Tobia, Cundinamarca (1. Además, hasta mediados de los años 40 del siglo pasado, el tifo epidémico (causado por R. prowazekii era endémico en muchas ciudades de Colombia, incluyendo Bogotá.

  7. The Where is Norovirus Control Lost (WINCL) Study: an enhanced surveillance project to identify norovirus index cases in care settings in the UK and Ireland

    Science.gov (United States)

    Wilson, Jennie; Haig, Caroline E; McCowan, Colin; Leanord, Alistair; Loveday, Heather

    2015-01-01

    Background: Norovirus outbreaks have a significant impact on all care settings; little is known about the index cases from whom these outbreaks initiate. Aim: To identify and categorise norovirus outbreak index cases in care settings. Methods: A mixed-methods, multi-centre, prospective, enhanced surveillance study identified and categorised index cases in acute and non-acute care settings. Results: From 54 participating centres, 537 outbreaks were reported (November 2013 to April 2014): 383 (71.3%) in acute care facilities (ACF); 115 (21.4%) in residential or care homes (RCH) and 39 (7.3%) in other care settings (OCS). Index cases were identified in 424 (79%) outbreaks. Of the 245 index cases who were asymptomatic on admission and not transferred within/into the care setting, 123 (50%) had been an inpatient/resident for 4 days. Four themes emerged: missing the diagnosis, care service under pressure, delay in outbreak control measures and patient/resident location and proximity. Conclusion: The true index case is commonly not identified as the cause of a norovirus outbreak with at least 50% of index cases being misclassified. Unrecognised norovirus cross-transmission occurs frequently suggesting that either Standard Infection Control Precautions (SICPs) are being insufficiently well applied, and or SICPs are themselves are insufficient to prevent outbreaks.

  8. EVALUATION OF MURINE NOROVIRUS, FELINE CALICIVIRUS, POLIOVIRUS, AND MS2 AS SURROGATES FOR HUMAN NOROVIRUS IN a Model of Viral Persistence in SURFACE Water AND GROUNDWATER

    Science.gov (United States)

    Human noroviruses (NoV) are a significant cause of non bacterial gastroenteritis worldwide with contaminated drinking water a potential transmission route. The absence of a cell culture infectivity model for NoV necessitates the use of molecular methods and/or viral surrogate mod...

  9. LAS GASTROENTERITIS VÍRICAS: UN PROBLEMA DE SALUD PÚBLICA

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    Angela Domínguez

    2009-01-01

    Full Text Available Las gastroenteritis agudas (GA constituyen un problema de salud importante, pudiendo estar causadas por bacterias, parásitos y virus enteropatógenos, entre los que se han reconocido hasta la actualidad rotavirus, astrovirus, adenovirus y calicivirus. La frecuencia de rotavirus como causa de casos esporádicos de GA oscila entre el 17,3% y el 37,4%. Aunque se ha sugerido que la exposición común no tiene mucha importancia para la difusión de este virus, resulta difícil relacionar casos aparentemente esporádicos, por lo que probablemente haya brotes que no llegan a detectarse. Los astrovirus causan GA con una frecuencia que oscila entre un 2 y un 26% y se han descrito brotes en escuelas y guarderías, pero también en población adulta y en ancianos. La frecuencia con que se identifican los adenovirus 40 y 41 como causa de GA esporádica en niños no inmunodeprimidos oscila entre 0,7% y 31,5%, aunque probablemente haya subdetección debido a que la sensibilidad de las técnicas convencionales es baja. Los calicivirus se separan filogenéticamente en dos géneros: Norovirus y Sapovirus. Los Norovirus se asocian frecuentemente con brotes de GA transmitidos por agua y alimentos . Se estima que el 40% de los casos de GA por Norovirus están vehiculados por alimentos. En Suecia y en algunas zonas de Estados Unidos es la primera causa de brotes de toxiinfecciones alimentarias. Recientemente se han descrito en Canadà y Japón brotes de transmisión persona a persona y también de transmisión alimentaria causados por Sapovirus, afectando tanto a población infantil como adulta.

  10. Norovirus Recombinant Strains Isolated from Gastroenteritis Outbreaks in Southern Brazil, 2004–2011

    Science.gov (United States)

    Leite, José Paulo Gagliardi; Miagostovich, Marize Pereira

    2016-01-01

    Noroviruses are recognized as one of the leading causes of viral acute gastroenteritis, responsible for almost 50% of acute gastroenteritis outbreaks worldwide. The positive single-strand RNA genome of noroviruses presents a high mutation rate and these viruses are constantly evolving by nucleotide mutation and genome recombination. Norovirus recombinant strains have been detected as causing acute gastroenteritis outbreaks in several countries. However, in Brazil, only one report of a norovirus recombinant strain (GII.P7/GII.20) has been described in the northern region so far. For this study, 38 norovirus strains representative of outbreaks, 11 GII.4 and 27 non-GII.4, were randomly selected and amplified at the ORF1/ORF2 junction. Genetic recombination was identified by constructing phylogenetic trees of the polymerase and capsid genes, and further SimPlot and Bootscan analysis of the ORF1/ORF2 overlap. Sequence analysis revealed that 23 out of 27 (85%) non-GII.4 noroviruses were recombinant strains, characterized as: GII.P7/GII.6 (n = 9); GIIP.g/GII.12 (n = 4); GII.P16/GII.3 (n = 4); GII.Pe/GII.17 (n = 2); GII.P7/GII.14 (n = 1); GII.P13/GII.17 (n = 1); GII.P21/GII.3 (n = 1); and GII.P21/GII.13 (n = 1). On the other hand, among the GII.4 variants analyzed (Den Haag_2006b and New Orleans_2009) no recombination was observed. These data revealed the great diversity of norovirus recombinant strains associated with outbreaks, and describe for the first time these recombinant types circulating in Brazil. Our results obtained in southern Brazil corroborate the previous report for the northern region, demonstrating that norovirus recombinant strains are circulating more frequently than we expected. In addition, these results emphasize the relevance of including ORF1/ORF2-based analysis in surveillance studies as well as the importance of characterizing strains from other Brazilian regions to obtain epidemiological data for norovirus recombinant strains circulating in the

  11. Brote de varicela en el Servicio de Oncología de hombres del Hospital San Juan de Dios, febrero-abril de 2004, San José, Costa Rica Chicken pox outbreak in the male Oncology Ward at he Hospital San Juan de Dios Hospital, febrero-abril de 2004

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    Sócrates Vargas-Naranjo

    2008-03-01

    Full Text Available Justificación y objetivo:La infección intrahospitalaria por varicela en adultos es infrecuente, a pesar de ser una enfermedad altamente contagiosa. Es reconocido que en adultos se presentan las tasas de letalidad más altas y por ello es importante analizar las características del presente brote y así determinar cuáles factores contribuyeron a que ocurriera, para recomendar acciones dirigidas a la prevención de un brote similar. Métodos: Se diseñó un estudio de casos y controles para identificar los factores asociados al brote por varicela en el hospital. La prueba de U de Mann-Whitney se utilizó para valorar diferencias entre casos y controles según edad, contacto entre pacientes, estancia hospitalaria y grupo de cama. El cálculo de los Odds Ratio ayudó a determinar la posible asociación entre las variables y la presentación de la enfermedad. Se recomendó la cuarentena del Servicio. Resultados:El primer caso de varicela ocurrió en febrero, al tercer día de su ingreso al hospital. Posteriormente, se presentaron 5 casos más. Al analizar las variables estudiadas, la curva epidémica y el período de incubación, la variable contacto entre los pacientes fue la más importante para mantener la existencia del brote p Aim: Varicella ’s infection is not common in adults ’ hospital, in spite of being a highly contagious illness. Since in adults, death rates are higher, it is important to analyze the characteristics of the present outbreak. We tried to determine risk factors that contributed to its existence in order to recommend measures to prevent future varicella outbreaks. Methods:A case and contols study was designed to identify factors associated to a varicella outbreak in the hospital. The U test of Mann-Whitney valued differences between cases and controls according to age, contact among patients hospital stay and bed group. Odds Ratio determined the possible association between the variables and the presentation of the

  12. Characterization and inhibition of norovirus proteases of genogroups I and II using a fluorescence resonance energy transfer assay

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    Chang, Kyeong-Ok [Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, KS 66506 (United States); Takahashi, Daisuke; Prakash, Om [Department of Biochemistry, Kansas State University, Manhattan, KS 66506 (United States); Kim, Yunjeong, E-mail: ykim@vet.ksu.edu [Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, KS 66506 (United States)

    2012-02-20

    Noroviruses are the major cause of food- or water-borne gastroenteritis outbreaks in humans. The norovirus protease that cleaves a large viral polyprotein to nonstructural proteins is essential for virus replication and an attractive target for antiviral drug development. Noroviruses show high genetic diversity with at least five genogroups, GI-GV, of which GI and GII are responsible for the majority of norovirus infections in humans. We cloned and expressed proteases of Norwalk virus (GI) and MD145 virus (GII) and characterized the enzymatic activities with fluorescence resonance energy transfer substrates. We demonstrated that the GI and GII proteases cleaved the substrates derived from the naturally occurring cleavage site in the open reading frame (ORF) 1 of G1 norovirus with similar efficiency, and that enzymatic activity of both proteases was inhibited by commercial protease inhibitors including chymostatin. The interaction of chymostatin to Norwalk virus protease was validated by nuclear magnetic resonance (NMR) spectroscopy.

  13. Influence of School Year on Seasonality of Norovirus Outbreaks in Developed Countries

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    Babenko, Oksana; Honish, Lance

    2017-01-01

    Factors affecting the seasonal distribution of norovirus outbreaks are not well understood. This study examined whether grade school settings at the start of the school year may be a factor. We searched Ovid Medline from January 2002 to June 2014 for studies that provided all reported norovirus outbreaks in a developed country by month for a minimum of three years. Historical school years were obtained from verifiable sources. The start of the norovirus seasonal outbreak peak and peak outbreak month were determined for each study and compared to the start month of school. Northern hemisphere and southern hemisphere countries had a different norovirus seasonality and different school year structures (traditional compared to year round). In the two studies that provided outbreaks by age, outbreaks among children started several months before outbreaks in the adult population. The median number of months between school start and start of the seasonal outbreak peak was two months (interquartile range [IQR] = 2.0–3.0), while the median number of months between school start and peak outbreak month was four months (IQR = 3.0–4.0). These findings suggest the possibility the school setting at the start of the school year may be a factor in the seasonality of norovirus. PMID:28167970

  14. Complete Nucleotide Sequence Analysis of the Norovirus GII.4 Sydney Variant in South Korea

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    Ji-Sun Park

    2015-01-01

    Full Text Available Norovirus is the primary cause of acute gastroenteritis in individuals of all ages. In Australia, a new strain of norovirus (GII.4 was identified in March 2012, and this strain has spread rapidly around the world. In August 2012, this new GII.4 strain was identified in patients in South Korea. Therefore, to examine the characteristics of the epidemic norovirus GII.4 2012 variant in South Korea, we conducted KM272334 full-length genomic analysis. The genome of the gg-12-08-04 strain consisted of 7,558 bp and contained three open reading frame (ORF composites throughout the whole genome: ORF1 (5,100 bp, ORF2 (1,623 bp, and ORF3 (807 bp. Phylogenetic analyses showed that gg-12-08-04 belonged to the GII.4 Sydney 2012 variant, sharing 98.92% nucleotide similarity with this variant strain. According to SimPlot analysis, the gg-12-08-04 strain was a recombinant strain with breakpoint at the ORF1/2 junction between Osaka 2007 and Apeldoorn 2008 strains. This study is the first report of the complete sequence of the GII.4 Sydney 2012 strain in South Korea. Therefore, this may represent the standard sequence of the norovirus GII.4 2012 variant in South Korea and could therefore be useful for the development of norovirus vaccines.

  15. Clinical usefulness of oral immunoglobulins in lung transplant recipients with norovirus gastroenteritis: a case series.

    Science.gov (United States)

    Gairard-Dory, A-C; Dégot, T; Hirschi, S; Schuller, A; Leclercq, A; Renaud-Picard, B; Gourieux, B; Kessler, R

    2014-12-01

    Viral gastroenteritis causing diarrhea is a common complication observed in lung transplant recipients. Differently from the mild and typically self-limited disease seen in immunocompetent subjects, immunocompromised patients frequently have a more severe course. Norovirus and rotavirus are among the leading causes of severe gastroenteritis in transplant recipients. Specific treatment is unavailable, although good supportive treatment can significantly reduce morbidity. Previous studies have suggested that oral immunoglobulins may be used for the treatment of acute viral gastroenteritis after solid-organ transplantation. Herein, we conducted a retrospective chart review of 12 lung transplant recipients with norovirus-induced gastroenteritis who were treated with oral immunoglobulins for 2 days. Eleven patients were successfully treated, whereas 1 subject was only mildly improved. Four patients had at least 1 recurrence. No significant adverse effects were observed. We conclude that oral immunoglobulins may be clinically useful for lung transplant recipients with norovirus-induced gastroenteritis.

  16. Efecto de Biobras-6 y el MH-5 en la induccion de callos y brotes en lechuga

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    Miriam Núñez

    2004-01-01

    Full Text Available Con el objetivo de evaluar el efecto que dos análogos espirostánicos de brasinoesteroides denominados comercialmente Biobras-6 y MH-5, ejercen en la formación de callos y regeneración de plantas de lechuga (Lactuca sativa var. Brasil 221, se ejecutaron dos experimentos de laboratorio. En el primero, se adicionaron ambos análogos, en dos concentraciones (0.001 y 0.01 mg.L-1, al medio de cultivo basal MS que contenía 6-BAP 0.1 mg.L-1, mientras que en el segundo experimento, se adicionaron los productos en ambas concentraciones, pero la concentración de citoquinina se redujo a la mitad. En ambos casos, se utilizó como tratamiento control el medio de cultivo MS en presencia de 6-BAP 0.1 mg.L-1. Los resultados demostraron que el Biobras-6 y el MH-5 estimularon la formación de callos y brotes a partir de cotiledones solamente cuando se añadieron, a determinadas concentraciones, al medio de cultivo con la presencia de 6-BAP 0.1 mg.L-1.

  17. Occurrence of Noroviruses and Their Correlation with Microbial Indicators in Raw Milk.

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    Yavarmanesh, Masoud; Alum, Absar; Abbaszadegan, Morteza

    2015-09-01

    This study was conducted to investigate the microbiological quality of raw cow's milk in a collection center in the city of Mashhad, Iran. A total of 19 raw cow's milk samples were collected and simultaneously analyzed for male-specific (F(+)) coliphage and Escherichia coli using culture-based methods and for enteric viruses by reverse transcriptase semi-nested PCR using primer sets specific for human norovirus Group I (HNV-GI), human norovirus Group II (HNV-GII), and enteroviruses (EV). Seven out of 19 (36.8%) raw milk samples tested positive for human noroviruses (HNV). The genotypes detected were HNV-GI and HNV-GII. Three positive samples contained both genotypes, and 2 samples were positive for either of HNV-GI and HNV-GII. No sample tested positive for EV. The correlation between the occurrence of HNV and the microbial indicators was studied. The statistical analysis using first- and second-order regression revealed that there is no correlation between F(+) coliphage and E. coli. Similarly, no correlation was noticed between the occurrence of F(+) coliphages and HNV. However, frequency distribution analysis indicated that 3 out of 4 (75%) of raw milk samples containing F(+) coliphage at a concentration higher than 10(4) pfu/100 ml were also positive for noroviruses. The limited data on the occurrence of noroviruses in raw milk suggest a poor sanitation and hygiene practices at the facility and indicate a possible correlation between the viral indicator at high concentration and human noroviruses; however, this analysis needs further investigation in a larger scale study.

  18. Caracterización epidemiológica, clínica y microbiológica del brote de diarrea asociado a Clostridium difficile, ocurrido en el Hospital San Juan de Dios, 2008-2009

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    Manuel Antonio Villalobos-Zúñiga

    2012-09-01

    Full Text Available Antecedentes: la enfermedad diarreica asociada a Clostridium difficile (EDACD es la causa más importante de diarrea nosocomial en el mundo. En Costa Rica, se presentó recientemente un brote de EDACD en el Hospital San Juan de Dios de San José, hospital de tercer nivel con 700 camas. En el estudio se analizan las características epidemiológicas, clínicas y microbiológicas de los pacientes con EDACD atendidos entre noviembre de 2008 y junio de 2009. Pacientes y métodos: se definió como caso de EDACD un paciente con cuadro diarréico con detección de ELISA positiva por toxina A de C. difficile en heces. Se realizó un análisis de la incidencia anual desde 2004 de EDACD, y de la incidencia mensual de EDACD en 2009 en el HSJD, así como un estudio observacional y retrospectivo de 112 expedientes médicos correspondientes a pacientes con el diagnóstico de EDACD atendidos en el Hospital, en el periodo comprendido entre el 15 de noviembre de 2008 y el 15 de junio de 2009. El análisis de los datos se efectuó mediante pruebas estadísticas descriptivas y medidas de asociación. Resultados: la incidencia de EDACD aumentó desde finales de 2008, y alcanzó su pico máximo en abril de 2009, cuando se implementaron medidas sanitarias que disminuyeron en un 75% el número de pacientes en 8 meses. De los 112 expedientes médicos revisados, 63 (56% fueron hombres. La edad promedio fue de 65,33 años; 103 (92% pacientes desarrollaron su enfermedad mientras estuvieron hospitalizados; el tiempo promedio de internamiento fue de 18,6 días. Solo el 9% no presentó ninguna comorbilidad. Las comorbilidades más frecuentes fueron: HTA y DM tipo 2, con un 57,5% y un 39,8%, respectivamente, y enfermedad neuropsiquiátrica en un 29,2%. El 96% (107 pacientes había recibido tres o más antibióticos antes del inicio de la diarrea. La duración promedio de la antibióticoterapia fue de 32 días por paciente. En promedio, la duración de la diarrea fue de 10,2 d

  19. Thermal inactivation of human norovirus surrogates in spinach and measurement of its uncertainty.

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    Bozkurt, Hayriye; D'souza, Doris H; Davidson, P Michael

    2014-02-01

    Leafy greens, including spinach, have potential for human norovirus transmission through improper handling and/or contact with contaminated water. Inactivation of norovirus prior to consumption is essential to protect public health. Because of the inability to propagate human noroviruses in vitro, murine norovirus (MNV-1) and feline calicivirus (FCV-F9) have been used as surrogates to model human norovirus behavior under laboratory conditions. The objectives of this study were to determine thermal inactivation kinetics of MNV-1 and FCV-F9 in spinach, compare first-order and Weibull models, and measure the uncertainty associated with the process. D-values were determined for viruses at 50, 56, 60, 65, and 72 °C in 2-ml vials. The D-values calculated from the first-order model (50 to 72 °C) ranged from 0.16 to 14.57 min for MNV-1 and 0.15 to 17.39 min for FCV-9. Using the Weibull model, the tD for MNV-1 and FCV-F9 to destroy 1 log (D ≈ 1) at the same temperatures ranged from 0.22 to 15.26 and 0.27 to 20.71 min, respectively. The z-values determined for MNV-1 were 11.66 ± 0.42 °C using the Weibull model and 10.98 ± 0.58 °C for the first-order model and for FCV-F9 were 10.85 ± 0.67 °C and 9.89 ± 0.79 °C, respectively. There was no difference in D- or z-value using the two models (P > 0.05). Relative uncertainty for dilution factor, personal counting, and test volume were 0.005, 0.0004, and ca. 0.84%, respectively. The major contribution to total uncertainty was from the model selected. Total uncertainties for FCV-F9 for the Weibull and first-order models were 3.53 to 7.56% and 11.99 to 21.01%, respectively, and for MNV-1, 3.10 to 7.01% and 13.14 to 16.94%, respectively. Novel and precise information on thermal inactivation of human norovirus surrogates in spinach was generated, enabling more reliable thermal process calculations to control noroviruses. The results of this study may be useful to the frozen food industry in designing blanching processes for

  20. Population-Based Incidence Rates of Diarrheal Disease Associated with Norovirus, Sapovirus, and Astrovirus in Kenya.

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    Kayoko Shioda

    Full Text Available Diarrheal diseases remain a major cause of mortality in Africa and worldwide. While the burden of rotavirus is well described, population-based rates of disease caused by norovirus, sapovirus, and astrovirus are lacking, particularly in developing countries.Data on diarrhea cases were collected through a population-based surveillance platform including healthcare encounters and household visits in Kenya. We analyzed data from June 2007 to October 2008 in Lwak, a rural site in western Kenya, and from October 2006 to February 2009 in Kibera, an urban slum. Stool specimens from diarrhea cases of all ages who visited study clinics were tested for norovirus, sapovirus, and astrovirus by RT-PCR.Of 334 stool specimens from Lwak and 524 from Kibera, 85 (25% and 159 (30% were positive for norovirus, 13 (4% and 31 (6% for sapovirus, and 28 (8% and 18 (3% for astrovirus, respectively. Among norovirus-positive specimens, genogroup II predominated in both sites, detected in 74 (87% in Lwak and 140 (88% in Kibera. The adjusted community incidence per 100,000 person-years was the highest for norovirus (Lwak: 9,635; Kibera: 4,116, followed by astrovirus (Lwak: 3,051; Kibera: 440 and sapovirus (Lwak: 1,445; Kibera: 879. For all viruses, the adjusted incidence was higher among children aged <5 years (norovirus: 22,225 in Lwak and 17,511 in Kibera; sapovirus: 5,556 in Lwak and 4,378 in Kibera; astrovirus: 11,113 in Lwak and 2,814 in Kibera compared to cases aged ≥5 years.Although limited by a lack of controls, this is the first study to estimate the outpatient and community incidence rates of norovirus, sapovirus, and astrovirus across the age spectrum in Kenya, suggesting a substantial disease burden imposed by these viruses. By applying adjusted rates, we estimate approximately 2.8-3.3 million, 0.45-0.54 million, and 0.77-0.95 million people become ill with norovirus, sapovirus, and astrovirus, respectively, every year in Kenya.

  1. Recombinant porcine norovirus identified from piglet with diarrhea

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    Shen Quan

    2012-09-01

    Full Text Available Abstract Background Noroviruses (NoVs are members of the family Caliciviridae and are emerging enteric pathogens of humans and animals. Some porcine NoVs are genetically similar to human strains and are classified into GII, like most epidemic human NoVs. So far, PoNoV have been exclusively detected in fecal samples of adult pig without clinical signs. Results Result showed that 2 of the 12 evaluated fecal samples were positive for PoNoVs, one of which was positive for PoNoV alone, and the other was coinfected with porcine circovirus and PoNoV. Phylogenetic and recombination analysis showed that the PoNoV positive alone strain was a recombinant new genotype strain. Experimental infection of miniature pigs with fecal suspensions confirmed that this strain can cause gastroenteritis in piglets. Conclusion This is the first report that recombinant new genotype PoNoV exised in pig herd of China, which cause diarrhea in pigs in nature condition. This find raised questions about the putative epidemiologic role of PoNoV.

  2. An Efficient Method of Noroviruses Recovery from Oysters and Clams

    Institute of Scientific and Technical Information of China (English)

    ZHOU Deqing; MA Liping; ZHAO Feng; YAO Lin; SU Laijin; LI Xinguang

    2013-01-01

    Noroviruses (NoVs) are widespread causes of nonbacterial gastroenteritis.Outbreaks of NoVs caused diseases are commonly ascribed to the consumption of contaminated shellfish.The concentration and RNA extraction of NoVs are crucial steps of detecting NoVs in shellfish.This study aimed to select a simple,rapid and highly efficient recovery method of NoVs detection with real-time RT-PCR.Four methods of recovering GI.3 and GII.4 NoVs from spiked digestive tissues of oysters and clams,respectively,were compared,of them,the method involving proteinase K and PEG 8000 was found the most efficient.With this method,9.3% and 13.1% of GI.3 and GII.4 NoVs were recovered from oysters and 9.6% and 12.3% of GI.3 and GII.4 NoVs were recovered from clams,respectively.This method was further used to detect NoVs in 84 oysters (Crassostrea gigas) and 86 clams (Ruditapes philippinarum) collected from 10 coastal cities in China from Jan.2011 to Feb.2012.The NoVs isolation rates were 10.47% of clams (9/86) and 7.14% of oysters (6/84).All the detected NoVs belonged to genotype GII.The NoVs recovery method selected is efficient for NoVs detection in oysters and clams.

  3. An efficient method of noroviruses recovery from oysters and clams

    Science.gov (United States)

    Zhou, Deqing; Ma, Liping; Zhao, Feng; Yao, Lin; Su, Laijin; Li, Xinguang

    2013-03-01

    Noroviruses (NoVs) are widespread causes of nonbacterial gastroenteritis. Outbreaks of NoVs caused diseases are commonly ascribed to the consumption of contaminated shellfish. The concentration and RNA extraction of NoVs are crucial steps of detecting NoVs in shellfish. This study aimed to select a simple, rapid and highly efficient recovery method of NoVs detection with real-time RT-PCR. Four methods of recovering GI.3 and GII.4 NoVs from spiked digestive tissues of oysters and clams, respectively, were compared, of them, the method involving proteinase K and PEG 8000 was found the most efficient. With this method, 9.3% and 13.1% of GI.3 and GII.4 NoVs were recovered from oysters and 9.6% and 12.3% of GI.3 and GII.4 NoVs were recovered from clams, respectively. This method was further used to detect NoVs in 84 oysters ( Crassostrea gigas) and 86 clams ( Ruditapes philippinarum) collected from 10 coastal cities in China from Jan. 2011 to Feb. 2012. The NoVs isolation rates were 10.47% of clams (9/86) and 7.14% of oysters (6/84). All the detected NoVs belonged to genotype GII. The NoVs recovery method selected is efficient for NoVs detection in oysters and clams.

  4. Inactivation of murine norovirus and feline calicivirus during oyster fermentation.

    Science.gov (United States)

    Seo, Dong Joo; Lee, Min Hwa; Seo, Jina; Ha, Sang-Do; Choi, Changsun

    2014-12-01

    Fermented seafood is popular in Asian countries. This study examined the survival of feline calicivirus (FCV) and murine norovirus (MNV) during oyster fermentation. Oysters spiked with FCV and MNV were fermented with 5% or 10% salt at 18 °C for 15 days, and MNV and FCV titers, lactic acid bacteria (LAB) populations, pH, and enzymatic activity were measured at 0, 1, 3, 5, 7, 10, and 15 days post-fermentation (DPF). Reductions in MNV and FCV were greater in 5% NaCl-supplemented oysters than in 10% NaCl-supplemented oysters. In 5% NaCl oysters, MNV and FCV titers significantly decreased by 1.60 log and 3.01 log, respectively, at 15 DPF. Populations of LAB increased from 3.62 log10 colony-forming units/g at 0 DPF to 8.77 log10 colony-forming units/g at 15 DPF during oyster fermentation supplemented with 5% NaCl supplementation, and the pH decreased gradually from 5.38 at 0 DPF to 4.17 at 15 DPF. During oyster fermentation, α-amylase, proteinase, and lipase were produced at higher levels in 5% salted oysters than in 10% salted oysters (P oysters could contribute to a reduction in foodborne viruses.

  5. Temporal dynamics of norovirus determined through monitoring of municipal wastewater by pyrosequencing and virological surveillance of gastroenteritis cases.

    Science.gov (United States)

    Kazama, Shinobu; Masago, Yoshifumi; Tohma, Kentaro; Souma, Nao; Imagawa, Toshifumi; Suzuki, Akira; Liu, Xiaofang; Saito, Mayuko; Oshitani, Hitoshi; Omura, Tatsuo

    2016-04-01

    Norovirus is a leading etiological agent of viral gastroenteritis. Because of relatively mild disease symptoms and frequent asymptomatic infections, information on the ecology of this virus is limited. Our objective was to examine the genetic diversity of norovirus circulating in the human population by means of genotyping the virus in municipal wastewater. We investigated norovirus genogroups I and II (GI and GII) in municipal wastewater in Japan by pyrosequencing and quantitative PCR (qPCR) from November 2012 to March 2013. Virological surveillance for gastroenteritis cases was concurrently conducted in the same area. A total of fourteen distinct genotypes in total (GI.1, 3, 4, 6, 7, GII.2, 4, 5, 6, 7, 12, 13, 14, and 17), with up to eight genotypes detected per sample, were observed in wastewater using pyrosequencing; only four genotypes (GI.6, GII.4, 5, and 14) were obtained from clinical samples. Seventy-eight percent of norovirus-positive stool samples contained GII.4, but this genotype was not dominant in wastewater. The norovirus GII.4 Sydney 2012 variant, which appeared and spread during our study period, was detected in both the wastewater and clinical samples. These results suggest that an environmental approach using pyrosequencing yields a more detailed distribution of norovirus genotypes/variants. Thus, wastewater monitoring by pyrosequencing is expected to provide an effective analysis of the distribution of norovirus genotypes causing symptomatic and asymptomatic infections in human populations.

  6. A SYBR Green RT-PCR assay in single tube to detect human and bovine noroviruses and control for inhibition

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    Saegerman Claude

    2008-08-01

    Full Text Available Abstract Background Noroviruses are single-stranded RNA viruses belonging to the family Caliciviridae. They are a major cause of epidemic and sporadic gastroenteritis in humans and clinical signs and lesions of gastroenteritis were reported in bovines. Due to their genetic proximity, potential zoonotic transmission or animal reservoir can be hypothesized for noroviruses. RT-PCR has become the "gold standard" for the detection of noroviruses in faecal and environmental samples. With such samples, the control for inhibition of the reaction during amplification and detection is crucial to avoid false negative results, which might otherwise not be detected. The aim of the reported method is to detect, with a SYBR Green technology, a broad range of noroviruses with a control for inhibition. Results A SYBR Green real-time RT-PCR assay was developed making use of a foreign internal RNA control added in the same tube. This assay is able to detect human and bovine noroviruses belonging to genogroups I, II and III and to distinguish between norovirus and internal control amplicons using melting curve analysis. A 10-fold dilution of samples appears to be the method of choice to remove inhibition. This assay was validated with human and bovine stool samples previously tested for norovirus by conventional RT-PCR. Conclusion This SYBR Green real-time RT-PCR assay allows the detection of the most important human and bovine noroviruses in the same assay, and avoids false negative results making use of an internal control. Melting curves allow the discrimination between the internal control and norovirus amplicons. It gives preliminary information about the species of origin. The sensitivity of the developed assay is higher than conventional RT-PCR and a 10-fold dilution of samples showed a better efficiency and reproducibility to remove RT-PCR inhibition than addition of bovine serum albumin.

  7. Evaluation of real-time RT-PCR assays for detection and quantification of norovirus genogroups I and II.

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    Rupprom, Kitwadee; Chavalitshewinkoon-Petmitr, Porntip; Diraphat, Pornphan; Kittigul, Leera

    2017-02-20

    Noroviruses are the leading cause of acute gastroenteritis in humans. Real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) is a promising molecular method for the detection of noroviruses. In this study, the performance of three TaqMan real-time RT-PCR assays was assessed, which were one commercially available real-time RT-PCR kit (assay A: Norovirus Real Time RT-PCR kit) and two in-house real-time RT-PCR assays (assay B: LightCycler RNA Master Hybprobe and assay C: RealTime ready RNA Virus Master). Assays A and B showed higher sensitivity than assay C for norovirus GI, while they all had the same sensitivity (10(3) DNA copies/mL) for GII DNA standard controls. Assay B had the highest efficiency for both genogroups. No cross-reactivity was observed among GI and GII noroviruses, rotavirus, hepatitis A virus, and poliovirus. The detection rates of these assays in GI and GII norovirus-positive fecal samples were not significantly different. However, the mean quantification cycle (Cq) value of assay B for GII was lower than assays A and C with statistical significance (P-value, 0.000). All three real-time RT-PCR assays could detect a variety of noroviruses including GI.2, GII.2, GII.3, GII.4, GII.6, GII.12, GII.17, and GII.21. This study suggests assay B as a suitable assay for the detection and quantification of noroviruses GI and GII due to good analytical sensitivity and higher performance to amplify norovirus on DNA standard controls and clinical samples.

  8. Identification of environmental determinants for spatio-temporal patterns of norovirus outbreaks in Korea using a geographic information system and binary response models.

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    Kim, Jin Hwi; Lee, Dong Hoon; Joo, Yongsung; Zoh, Kyung Duk; Ko, Gwangpyo; Kang, Joo-Hyon

    2016-11-01

    Although norovirus outbreaks are well-recognized to have strong winter seasonality relevant to low temperature and humidity, the role of artificial human-made features within geographical areas in norovirus outbreaks has rarely been studied. The aim of this study is to assess the natural and human-made environmental factors favoring the occurrence of norovirus outbreaks using nationwide surveillance data. We used a geographic information system and binary response models to examine whether the norovirus outbreaks are spatially patterned and whether these patterns are associated with specific environmental variables including service levels of water supply and sanitation systems and land-use types. The results showed that small-scale low-tech local sewage treatment plants and winter sports areas were statistically significant factors favoring norovirus outbreaks. Compactness of the land development also affected the occurrence of norovirus outbreaks; transportation, water, and forest land-uses were less favored for effective transmission of norovirus, while commercial areas were associated with an increased rate of norovirus outbreaks. We observed associations of norovirus outbreaks with various outcomes of human activities, including discharge of poorly treated sewage, overcrowding of people during winter season, and compactness of land development, which might help prioritize target regions and strategies for the management of norovirus outbreaks.

  9. A Synergy Effect of Trisodium Phosphate and Ethanol on Inactivation of Murine Norovirus 1 on Lettuce and Bell Pepper.

    Science.gov (United States)

    Kim, Eun-Jin; Lee, Young-Duck; Kim, Kwang-Yup; Park, Jong-Hyun

    2015-12-28

    The synergy effect of trisodium phosphate (TSP) and ethanol against murine norovirus 1 (MNV-1), as a surrogate for human noroviruses, on fresh produces was evaluated. More than 2% (w/v) of TSP effectively inactivated MNV-1. The single treatment of 1% TSP or 30% ethanol for 30 min was not effective on MNV-1; however, cotreatment showed inactivation of MNV-1 on stainless steel and the produces of lettuce and bell pepper under 15 min. The results suggest that cotreatment of TSP and ethanol at a low concentration and a short time of exposure might be useful for the reduction of norovirus in some produce.

  10. Brote intrahospitalario de escabiasis, a partir de un caso de sarna noruega Nosocomial outbreak of scabies from a Norwegian scabies case

    Directory of Open Access Journals (Sweden)

    Ramón Fajardo-Velázquez

    2004-06-01

    Full Text Available OBJETIVO: Describir un brote intrahospitalario de escabiasis ocurrido en la Ciudad de México, en agosto de 1999, como resultado de exposición a un caso de sarna noruega no diagnosticado oportunamente. MATERIAL Y MÉTODOS: Después de revisar el caso índice, instituimos aislamiento del paciente e identificamos casos secundarios de escabiasis entre pacientes hospitalizados, empleados que laboraban en el área afectada y sus familiares. Sólo individuos que padecían lesiones dérmicas y prurito fueron incluidos como casos infestados. Se establecieron medidas de control, como aislamiento de contacto, manejo apropiado de ropas contaminadas y tratamiento tópico. RESULTADOS: Un paciente con SIDA (caso índice de sarna noruega que cursaba con desequilibrio hidroelectrolítico severo fue admitido en el Hospital de Infectología, del Centro Médico Nacional La Raza, del Instituto Mexicano del Seguro Social, del 19 de julio al 20 de agosto de 1999, en la Ciudad de México. Veintiocho días después de su admisión emergieron casos de escabiasis entre los trabajadores de la salud; entonces, se sospechó de escabiasis noruega, lo que se confirmó por evidencia microscópica de los parásitos en una preparación de escamas del caso pista. Identificamos 48 casos secundarios con sarna clínica: 71% trabajadores de la salud, principalmente enfermeras (79%, 23% familiares de trabajadores y 6% pacientes. El periodo de incubación promedio fue de 15 días (intervalo 12 a 27. Aunque con mayor frecuencia las lesiones involucraron extremidades superiores (60%, las manos fueron respetadas. CONCLUSIONES: Este trabajo demuestra no sólo las dificultades para diagnosticar la escabiasis noruega en el hospedero inmunosuprimido, sino también la importancia de estar seguros de que los trabajadores de la salud cumplan con las precauciones estándar en todo momentoOBJECTIVE: To describe a nosocomial outbreak of scabies occurred in August 1999, resulting from exposure to

  11. Brote de dengue autóctono en el área metropolitana Buenos Aires: Experiencia del Hospital de Enfermedades Infecciosas F. J. Muñiz Outbreak of indigenous dengue in the Buenos Aires Metropolitan Area: Experience of the F.J. Muñiz Hospital

    Directory of Open Access Journals (Sweden)

    Alfredo Seijo

    2009-12-01

    Full Text Available Como consecuencia de la epidemia de dengue que afectó a la República de Bolivia y provincias del norte argentino, se produjo por primera vez un brote de dengue autóctono en el Area Metropolitana Buenos Aires. A partir de enero de 2009 asistimos casos de dengue importado hasta la tercera semana de marzo, cuando aparecieron los primeros casos por transmisión local, tendencia que se mantuvo hasta mediados de mayo. La mayor concentración de casos autóctonos atendidos residía en la región oeste de la ciudad de Buenos Aires y en localidades de los partidos de 3 de Febrero y La Matanza, que limitan con ella. Existieron factores concurrentes para que se produjera este brote: alta densidad vectorial, viajeros provenientes de regiones epidémicas concentrados por su domicilio en las áreas donde luego se produjo la transmisión local. El 95% ingresaron en los primeros días de viremia y en un período climático caracterizado por temperaturas medias elevadas que se mantuvieron hasta mediados de otoño. De los nueve pacientes con signos de alarma para el desarrollo de dengue grave, siete fueron casos autóctonos que no tenían antecedentes de haber padecido previamente dengue. Se comunican los hallazgos clínicos y epidemiológicos y se analizan los factores que regularon la transmisión.As a consequence of the dengue epidemic in the Bolivian Republic and the northern provinces of Argentina, an outbreak of indigenous dengue occurred for the first time in the Buenos Aires Metropolitan Area. Since January 2009 we assisted imported dengue cases coming from epidemic regions; later, around the end of March, and until middle autumn, indigenous cases appeared. The major concentration of these indigenous cases was in the west area of Buenos Aires City and in the neighboring localities 3 de Febrero and La Matanza. There were several factors that made the local transmission possible: a high vector density, people traveling from epidemic areas and clustering

  12. Análisis de un brote epidémico de brucelosis en trabajadores de un matadero

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    Luna Sánchez Antonio

    1998-01-01

    Full Text Available FUNDAMENTO: La notificación mediante el Sistema de Vigilancia Epidemiológica de un número inusual de casos de Brucelosis en trabajadores de un matadero a finales de 1996 hizo sospechar la existencia de un brote epidémico entre dicho colectivo profesional. MÉTODOS: Se recopiló la información disponible respecto a: 1 animales sacrificados en el matadero diagnosticados de brucelosis; 2 bajas laborales producidas y 3 datos de la mutualidad laboral relativos a los empleados del matadero con la enfermedad. Se realizó una encuesta epidemiológica a los trabajadores sobre los antecedentes de enfermedad, actividad laboral y riesgos no laborales (ingesta de leche o derivados sin higienizar. Las dependencias y actividades del matadero fueron inspeccionadas. Se diseñó un estudio de casos y controles. Se estudió cada puesto de trabajo tomando como controles a los restantes empleados del matadero. Para su verificación se realizó un estudio retrospectivo de cohortes. RESULTADOS: El brote epidémico de la enfermedad entre los trabajadores comenzó durante el mes de septiembre y duró hasta febrero del siguiente año. Las encuestas epidemiológicas descubrieron 28 trabajadores con síntomas sugestivos de la enfermedad, siendo los operarios del área de sacrificio del matadero quienes presentan la tasa de ataque más alta: 56%. En el estudio de casos y controles el riesgo más elevado se observó en dicho colectivo de trabajadores con una OR de 4,27 (IC 95%: 1,6-15 y p<0.01. Del mismo modo en el estudio de cohortes apreciamos que estos trabajadores presentan un RR de 2,5 (IC 95%: 1,5-4,3 cuando son comparados con el resto de trabajadores de la cohorte y de 8 (IC 95%: 2-30 si los comparamos con el colectivo de menor exposición. Los RR de los operarios de la limpieza y de la sala de despiece fueron de 6,56 (IC 95%: 1,6-27 para los primeros y de 4,77 (IC 95%: 1,1-21 para los segundos. Las fracciones etiológicas fueron del 87% para los de la zona de

  13. Propidium monoazide reverse transcription PCR and RT-qPCR for detecting infectious enterovirus and norovirus

    Science.gov (United States)

    Presently there is no established cell line or small animal model that allows for the detection of infectious human norovirus. Current methods based on RT-PCR and RT-qPCR detect both infectious and non-infectious virus and thus the conclusions that may be drawn regarding the publ...

  14. Efficacy of oxidizing disinfectants at inactivating murine norovirus on ready-to-eat foods.

    Science.gov (United States)

    Girard, Maryline; Mattison, Kirsten; Fliss, Ismail; Jean, Julie

    2016-02-16

    Noroviruses are the leading cause of foodborne illness, and ready-to-eat foods are frequent vehicles of their transmission. Studies of the disinfection of fruits and vegetables are becoming numerous. It has been shown that strong oxidizing agents are more effective than other chemical disinfectants for inactivating enteric viruses. The aim of this study was to evaluate the efficacy of oxidizing disinfectants (sodium hypochlorite, chloride dioxide and peracetic acid) at inactivating noroviruses on fruits and vegetables, using a norovirus surrogate, namely murine norovirus 3, which replicates in cell culture. Based on plaque assay, solutions of peracetic acid (85 ppm) and chlorine dioxide (20 ppm) reduced the infectivity of the virus in suspension by at least 3 log10 units after 1 min, while sodium hypochlorite at 50 ppm produced a 2-log reduction. On the surface of blueberries, strawberries and lettuce, chlorine dioxide was less effective than peracetic acid and sodium hypochlorite, which reduced viral titers by approximately 4 logs. A surprising increase in the efficacy of sodium hypochlorite on surfaces fouled with artificial feces was noted.

  15. Host genetic resistance to symptomatic norovirus (GGII.4) infections in Denmark

    DEFF Research Database (Denmark)

    Kindberg, Elin; Akerlind, Britt; Johnsen, Christina

    2007-01-01

    A total of 61 individuals involved in five norovirus outbreaks in Denmark were genotyped at nucleotides 428 and 571 of the FUT2 gene, determining secretor status, i.e., the presence of ABH antigens in secretions and on mucosa. A strong correlation (P = 0.003) was found between the secretor...

  16. Epidemiological investigation of a norovirus GII.4 Sydney outbreak in a China elder care facility.

    Science.gov (United States)

    Zheng, Qing-ming; Zeng, Hua-tang; Dai, Chuan-wen; Zhang, Shun-xiang; Zhang, Zhen; Mei, Shu-jiang; He, Ya-qing; Ma, Han-wu

    2015-01-01

    An outbreak of norovirus GII.4/Sydney_2012 affected a China elder care facility in December 2012. A total of 39 elderly people and staff met the outbreak case definition. The attack rates in the elderly and the staff were 15.9% (31/195) and 23.2% (19/82), respectively, including 13 asymptomatic cases in the staff. The result of gene sequencing revealed that the outbreak was caused by norovirus GII.4 Sydney. The mode of transmission of this outbreak was proven to be person-to-person. The first case (a self-cared elder) was affected outside the elder care facility and was not isolated after returning. Norovirus was transmitted via close contact among the self-cared elderly. Then, through service-related close contact, the attendants promoted the cross-transmission between the self-cared elderly and the nursed elderly. The virus was also spread among the staff via daily contact. In the elder care facility, the asymptomatic cases in the attendants played an important role in the transmission of norovirus, which deserves high attention.

  17. Norovirus outbreak associated with a hotel in the west of Ireland, 2006.

    Science.gov (United States)

    Michel, A; Fitzgerald, R; Whyte, D; Fitzgerald, A; Beggan, E; O'Connell, N; Greally, T

    2007-07-01

    An outbreak of gastrointestinal disease (nausea, vomiting or diarrhoea) occurred among a party of wedding guests, staff and other guests in a hotel in the west of Ireland, in October 2006. Upon notification, a multi-disciplinary outbreak control team was convened to investigate and control the outbreak. In all, 98 people were ascertained ill. The median duration of illness was 48 hours. The attack rate ranged between 48 and 85%. The hotel voluntarily notified health authorities and co-operated fully with investigation and control measures. Strict prevention and control measures were instituted promptly, including air ventilation, enhanced hand hygiene, isolation of cases, temporary "cooked food only", temporary alternative accommodation and specialised cleaning. Three cases of norovirus infection were laboratory-confirmed. There was no evidence of food- or water-borne transmission. Clinical and epidemiological findings indicated person-to-person transmission of norovirus. This report highlights the potential for large social gatherings to facilitate the spread of viral gastroenteritis by person-to-person transmission and via contaminated environment. Effective community management of this outbreak appears to have prevented its having an impact on local acute hospital services. The authors conclude that in addition to the existing national guidelines on the management of outbreaks of norovirus in healthcare settings, agreed guidelines for the management of norovirus outbreaks in the hotel and tourism industry are needed in Ireland.

  18. Optimization of methods for detecting norovirus on various fruit.

    Science.gov (United States)

    Kim, Hee-Yeon; Kwak, In-Shin; Hwang, In-Gyun; Ko, GwangPyo

    2008-11-01

    Methods for detecting norovirus (NoV) in food are crucial for investigation and prevention of outbreaks caused by NoV-contaminated food. However, current NoV detection methods have not been well examined or optimized. In this study, the effectiveness of various methods for eluting NoV from various fruit, concentrating the virus using polyethylene glycol (PEG), and extracting the viral RNA for subsequent assay by RT-PCR was optimized. First, six different buffers previously described for eluting NoV from fruit surfaces were evaluated. A known amount of NoV was spiked onto the surface of grapes, strawberries, and raspberries, and the virus was recovered with distilled water, 0.05 M glycine-0.14 M NaCl (pH 7.5), 2.9% tryptose phosphate broth-6% glycine, 100 mM Tris-HCl (pH 9.5), 50 mM glycine-50 mM MgCl(2) (pH 9.5), or 3% beef extract. Quantitation of the recovered virus using RT-PCR revealed that the most effective elution buffer was 3% beef extract. Secondly, to optimize a method for concentrating the recovered NoV, the key parameters of PEG precipitation, a typical method for concentrating enteric virus, were investigated. The influence of PEG molecular weight and the duration and temperature of the precipitation procedure were examined. NoV was concentrated most efficiently by precipitation when PEG (10,000) was used for 4h at room temperature. Finally, five different methods for nucleic acid extraction were evaluated. Among RNA extraction methods examined, QIAamp Viral RNA Mini kit showed the best recovery efficiency. Using the optimized method, approximately 6-80% of the seeded NoV was recovered from the various fruit.

  19. Norovirus P particle efficiently elicits innate, humoral and cellular immunity.

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    Hao Fang

    Full Text Available Norovirus (NoV P domain complexes, the 24 mer P particles and the P dimers, induced effective humoral immunity, but their role in the cellular immune responses remained unclear. We reported here a study on cellular immune responses of the two P domain complexes in comparison with the virus-like particle (VLP of a GII.4 NoV (VA387 in mice. The P domain complexes induced significant central memory CD4(+ T cell phenotypes (CD4(+ CD44(+ CD62L(+ CCR7(+ and activated polyclonal CD4(+ T cells as shown by production of Interleukin (IL-2, Interferon (IFN-γ, and Tumor Necrosis Factor (TNF-α. Most importantly, VA387-specific CD4(+ T cell epitope induced a production of IFN-γ, indicating an antigen-specific CD4(+ T cell response in P domain complex-immunized mice. Furthermore, P domain complexes efficiently induced bone marrow-derived dendritic cell (BMDC maturation, evidenced by up-regulation of co-stimulatory and MHC class II molecules, as well as production of IL-12 and IL-1β. Finally, P domain complex-induced mature dendritic cells (DCs elicited proliferation of specific CD4(+ T cells targeting VA387 P domain. Overall, we conclude that the NoV P domain complexes are efficiently presented by DCs to elicit not only humoral but also cellular immune responses against NoVs. Since the P particle is highly effective for both humoral and cellular immune responses and easily produced in Escherichia coli (E. coli, it is a good choice of vaccine against NoVs and a vaccine platform against other diseases.

  20. Análisis espacial de un brote de leishmaniasis en el sur del Área metropolitana de la Comunidad de Madrid. 2009-2013

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    Emiliano Aránguez Ruiz

    2014-06-01

    Full Text Available La leishmaniasis es una enfermedad zoonótica endémica en España. El objetivo de este estudio es realizar un análisis espacial de los elementos claves del ciclo de la enfermedad, vectores, reservorios y casos humanos, en un brote comunitario declarado en cuatro municipios del sur del Área metropolitana de Madrid: Fuenlabrada, Getafe, Humanes de Madrid y Leganés.Se analizaron 485 casos de leishmaniasis, declarados en el Sistema de Vigilancia Epidemiológica de la Comunidad de Madrid, con fecha de inicio de síntomas entre el 1 de julio de 2009 y el 30 de junio de 2013.La mayor parte de los casos se localizaron en el norte de Fuenlabrada. Los resultados del análisis espacial pusieron de manifiesto que, durante el periodo de estudio, la zona con mayor concentración de casos coincidió espacialmente con áreas residenciales periféricas inmediatas a espacios verdes con alta densidad de flebotomos y prevalencia relativamente elevada de leishmaniasis en lagomorfos. Esto informa de que la exposición principal ocurre en su entorno domiciliario o peridomiciliario.El estudio parece indicar que las infraestructuras viarias podrían haber tenido un papel decisivo en la distribución espacial del brote comportándose de diferentes maneras: barreras territoriales que aíslan en cierta medida a varios núcleos urbanos de la exposición al patógeno, vías de penetración del vector en el interior de otros núcleos o generadores de un entorno de hábitats idóneos para reservorios y vectores.El análisis espacial ha permitido orientar las actuaciones de prevención y control del brote y continúa siendo de gran utilidad en la evolución del mismo. Los sistemas de información geográfica son herramientas que ayudan a la comprensión de la génesis y evolución de los brotes de enfermedades infecciosas, así como al diseño de las intervenciones ambientales.

  1. Prevalence and molecular characterization of human noroviruses and sapoviruses in Ethiopia.

    Science.gov (United States)

    Sisay, Zufan; Djikeng, Appolinaire; Berhe, Nega; Belay, Gurja; Gebreyes, Wondwossen; Abegaz, Woldaregay Erku; Njahira, Moses N; Wang, Q H; Saif, Linda J

    2016-08-01

    Viral gastroenteritis is a major public health problem worldwide. In Ethiopia, very limited studies have been done on the epidemiology of enteropathogenic viruses. The aim of this study was to detect and characterize noroviruses (NoVs) and sapoviruses (SaVs) from acute gastroenteritis patients of all ages. Fecal samples were collected from diarrheic patients (n = 213) in five different health centers in Addis Ababa during June-September 2013. The samples were screened for caliciviruses by reverse transcription polymerase chain reaction (RT-PCR) using universal and genogroup-specific primer pairs. Phylogenetic analyses were conducted using the sequences of the PCR products. Of the clinical samples, 25.3 % and 4.2 % were positive for NoV and SaV RNA, respectively. Among the norovirus positives, 22 were sequenced further, and diverse norovirus strains were identified: GI (n = 4), GII (n = 17) and GIV (n = 1). Most strains were GII (n = 17/22: 77.2 %), which were further divided into three different genotypes (GII.4, GII.12/GII.g recombinant-like and GII.17), with GII.17 being the dominant (7/17) strain detected. GI noroviruses, in particular GI.4 (n = 1), GI.5 (n = 2) and GI.8 (n = 1), were also detected and characterized. The GIV strain detected is the first from East Africa. The sapoviruses sequenced were also the first reported from Ethiopia. Collectively, this study showed the high burden and diversity of noroviruses and circulation of sapoviruses in diarrheic patients in Ethiopia. Continued surveillance to assess their association with diarrhea is needed to define their epidemiology, disease burden, and impact on public health.

  2. Impact of genotype-specific herd immunity on the circulatory dynamism of norovirus: a 10-year longitudinal study of viral acute gastroenteritis.

    Science.gov (United States)

    Sakon, Naomi; Yamazaki, Kenji; Nakata, Keiko; Kanbayashi, Daiki; Yoda, Tomoko; Mantani, Masanobu; Kase, Tetsuo; Takahashi, Kazuo; Komano, Jun

    2015-03-15

    Human norovirus is a major cause of viral acute gastroenteritis worldwide. However, the transition of endemic norovirus genotypes remains poorly understood. The characteristics of natural immunity against norovirus are unclear because few studies have been performed in the natural infection setting. This prospective 10-year surveillance study of acute gastroenteritis in the province of Osaka, Japan, revealed that norovirus spread shows temporal, geographic, and age group-specific features in the humans. Genogroup II genotype 4 (GII.4) was detected in most sporadic pediatric cases, as well as in foodborne and nursing home outbreaks, respectively. The dominant genotypes in outbreaks at childcare facilities and schools shifted every season and involved GI, GII.2, GII.3, GII.4, and GII.6. Evidence at both the facility and individual levels indicated that genotype-specific herd immunity lasted long enough to influence the endemic norovirus genotype in the next season. Thus, norovirus circulates through human populations in a uniquely dynamic fashion.

  3. The Application of New Molecular Methods in the Investigation of a Waterborne Outbreak of Norovirus in Denmark, 2012

    DEFF Research Database (Denmark)

    van Alphen, Lieke B.; Dorleans, Frederique; Schultz, Anna Charlotte

    2014-01-01

    in order to control the outbreak. Norovirus GII.4 New Orleans 2009 variant was detected in 15 of 17 individual stool samples from 14 households. Norovirus genomic material from water samples was detected and quantified and sequencing of longer parts of the viral capsid region (>1000 nt) were applied...... to patient and water samples. All five purposely selected water samples tested positive for norovirus GII in levels up to 1.8×104 genomic units per 200 ml. Identical norovirus sequences were found in all 5 sequenced stool samples and 1 sequenced water sample, a second sequenced water sample showed 1 nt (....1%) difference. In a cohort study, including 256 participants, cases were defined as residents of the area experiencing diarrhoea or vomiting onset on 12–14 December 2012. We found an attack rate of 51%. Being a case was associated with drinking tap-water on 12–13 December (relative risk = 6.0, 95%CI: 1...

  4. Tres brotes de brucelosis investigados en un año de vigilancia de salud laboral en Ciudad Real Three outbreaks of brucellosis in a one-year period investigated by the occupational health service in Ciudad Real (Spain

    Directory of Open Access Journals (Sweden)

    Juan Castell Monsalve

    2009-12-01

    Full Text Available Presentamos 3 brotes investigados por nuestro servicio de salud laboral en el periodo de 1 año. Dos de ellos, con 2 casos cada uno, en sendas queserías industriales, y el tercero en un laboratorio pecuario perteneciente a la administración autonómica, también con 2 casos. En las 2 queserías se encontraron numerosas oportunidades para que los trabajadores pudieran haberse infectado; se consideró como de mayor riesgo la zona de descarga de leche, y la no utilización de equipos de protección individual por los trabajadores, las deficiencias en los laboratorios y la falta de separación efectiva de las dependencias fueron también potencials factores de riesgo. Respecto al laboratorio pecuario, se hallaron al menos 13 deficiencias importantes que permitían la fácil transmisión del agente infeccioso. En España, el riesgo de adquirir una infección por Brucella en laboratorios o industrias queseras es importante, y las condiciones y medidas para evitarlo que actualmente existen no son efectivas.We describe 3 outbreaks of brucellosis investigated by our Occupational Health Service in a 1-year period. Two of these outbreaks, with 2 cases each, occurred in 2 cheese factories and the third outbreak, also with 2 cases, occurred in a cattle laboratory belonging to the local government. In both cheese factories, numerous opportunities for the workers to become infected were found. The greatest risk was considered to be the area for unloading milk, while failure to use personal protection equipment by workers, deficiencies in the laboratories, and the lack of effective separation between areas were also potential risk factors. In the cattle laboratory, we found at least 13 major risk factors that could allow brucellosis transmission. In Spain, there is a substantial risk of Brucella infection in laboratories or dairy factories and current preventive measures are ineffective.

  5. The Viral Polymerase Inhibitor 2 '-C-Methylcytidine Inhibits Norwalk Virus Replication and Protects against Norovirus-Induced Diarrhea and Mortality in a Mouse Model

    OpenAIRE

    2013-01-01

    Human noroviruses are a major cause of food-borne illness, accountable for 50% of all-etiologies outbreaks of acute gastroenteritis (in both developing and developed countries). There is no vaccine or antiviral drug for the prophylaxis or treatment of norovirus-induced gastroenteritis. We recently reported the inhibitory effect of 2'-C-methylcytidine (2CMC), a hepatitis C virus polymerase inhibitor, on the in vitro replication of murine norovirus (MNV). Here we evaluated the inhibitory effect...

  6. Norovirus contamination levels in ground water treatment systems used for food-catering facilities in South Korea.

    Science.gov (United States)

    Lee, Bo-Ram; Lee, Sung-Geun; Park, Jong-Hyun; Kim, Kwang-Yup; Ryu, Sang-Ryeol; Rhee, Ok-Jae; Park, Jeong-Woong; Lee, Jeong-Su; Paik, Soon-Young

    2013-07-02

    This study aimed to inspect norovirus contamination of groundwater treatment systems used in food-catering facilities located in South Korea. A nationwide study was performed in 2010. Water samples were collected and, for the analysis of water quality, the temperature, pH, turbidity, and residual chlorine content were assessed. To detect norovirus genotypes GI and GII, RT-PCR and semi-nested PCR were performed with specific NV-GI and NV-GII primer sets, respectively. The PCR products amplified from the detected strains were then subjected to sequence analyses. Of 1,090 samples collected in 2010, seven (0.64%) were found to be norovirus-positive. Specifically, one norovirus strain was identified to have the GI-6 genotype, and six GII strains had the GII, GII-3, GII-4, and GII-17 genotypes. The very low detection rate of norovirus most likely reflects the preventative measures used. However, this virus can spread rapidly from person to person in crowded, enclosed places such as the schools investigated in this study. To promote better public health and sanitary conditions, it is necessary to periodically monitor noroviruses that frequently cause epidemic food poisoning in South Korea.

  7. Fluorinated TiO₂ as an ambient light-activated virucidal surface coating material for the control of human norovirus.

    Science.gov (United States)

    Park, Geun Woo; Cho, Min; Cates, Ezra L; Lee, David; Oh, Byung-Taek; Vinjé, Jan; Kim, Jae-Hong

    2014-11-01

    We evaluated the virucidal efficacy of light-activated fluorinated TiO₂ surface coatings on human norovirus and several surrogates (bacteriophage MS2, feline calcivirus (FCV), and murine norovirus (MNV)). Inactivation of viruses on surfaces exposed to a common fluorescent lamp was monitored and the effects of UVA intensity, temperature, and fluoride content were assessed. Destruction of RNA and capsid oxidation were evaluated for human norovirus inocula on the F-TiO₂ surfaces, while contact with the F-TiO₂ surface and exposure to residual UVA radiation of 10 μW cm(-2) for 60 min resulted in infectivity reductions for the norovirus surrogates of 2-3 log₁₀. Infectivity reductions on pristine TiO₂ surfaces in identical conditions were over 2 orders of magnitude lower. Under realistic room lighting conditions, MS2 infectivity declined below the lower detection limit after 12h. Reductions in RNA were generally low, with the exception of GII.4, while capsid protein oxidation likely played a larger role in infectivity loss. Inactivation of norovirus surrogates occurred significantly faster on F-TiO₂ compared to pristine TiO₂ surfaces. The material demonstrated antiviral action against human norovirus surrogates and was shown to effectively inhibit MS2 when exposed to residual UVA present in fluorescent room lighting conditions in a laboratory setting.

  8. Detection and differentiation of norovirus genogroups I and II from clinical stool specimens using real-time PCR.

    Science.gov (United States)

    Ramanan, Poornima; Espy, M J; Khare, Reeti; Binnicker, M J

    2017-04-01

    A real-time RT-PCR assay was designed to detect and differentiate norovirus genogroups I (GI) and II (GII), with primers and probes targeting the nonstructural polyprotein gene. Stool samples (n = 100) submitted for routine testing by the BioFire FilmArray® GI panel were also tested by the norovirus GI/GII real-time PCR assays. When compared to the FilmArray GI panel, the norovirus real-time PCR assay demonstrated a sensitivity of 77.5% (62/80) and specificity of 95% (19/20). Specimens yielding discordant results (n = 19) were tested at two outside laboratories for adjudication. Following discordant resolution, the adjusted sensitivity and specificity of the norovirus real-time PCR assays were 96.9% (63/65) and 100% (35/35), respectively. These results suggest that the real-time PCR assays are able to accurately detect and differentiate norovirus GI/GII from clinical stool specimens. Furthermore, our report highlights a potential issue with the specificity of the BioFire FilmArray® norovirus assay, which warrants additional investigation.

  9. ESTUDIO DE UN BROTE EPIDÉMICO DE TOS FERINA EN CASTELLÓN

    Directory of Open Access Journals (Sweden)

    Francisco González Morán

    2002-01-01

    Full Text Available Fun da men to: A par tir de la de claración de va rios ca sos en un cen tro es co lar se ini cia el es tu dio de bro te con el ob je ti vo de ca rac te ri zar éste des de el pun to de vis ta de per sona, lu gar y tiem po; se cal cu la la efec ti vi dad de la va cu na, y se es tu dia la con cor dan cia en tre los ca sos y el re sul ta do po si ti vo del es tudio se ro ló gi co. Mé to dos: Se de fine caso a la per so na que pre sen ta tos per - sis ten te de dos se manas de du ra ción. Se rea li za es tu dio de la di - fu sión de la en fer me dad a tra vés de la cur va epi dé mi ca, y de la efec ti vi dad de la do sis de re fuer zo de la va cu na an ti per tus sis. La con cor dan cia en tre los ca sos y la se ro lo gía po si ti va se eva - lúa por el ín dice Kappa. Re sul ta dos: Entre los alum nos de va rios cen tros es colares y sus con vi vien tes se en cues ta a 130 per so nas, de los que 94 en - tran en la de fi ni ción de caso. La me dia de edad de los ca sos es 10,5 años, un 42,6% son va ro nes, el 84% es co la res, el 71,3% mues tra sig nos de in fección re ciente (IgM po si ti va, y el tiem - po me dio des de la úl ti ma do sis de va cu na an ti per tus sis es de 8,25 años. La efec ti vi dad de la do sis de re fuer zo de la va cu na es del 66%. La con cor dan cia en tre los ca sos y el re sul ta do po si ti - vo de la se ro lo gía mues tra un Kappa igual a 0,45. No se ais ló B. Per tus sis en las 25 mues tras de fro tis fa ríngeo. Conclusiones: Las au las y el me dio fa mi liar son un fac tor de di fu sión de la en fer me dad. La in clu sión de una do sis de re - fuer zo a los 18 me ses me jora la efec ti vi dad de la va cu na an ti - per tus sis. El ais la mien to de la B. Per tus sis es poco fre cuen te, y la se ro lo gía, pue de ser una al ter na ti va ante la sos pe cha clí ni ca de la en fer me dad.

  10. Development of a Nanobody-Based Lateral Flow Immunoassay for Detection of Human Norovirus

    Science.gov (United States)

    Doerflinger, Sylvie Y.; Tabatabai, Julia; Schnitzler, Paul; Farah, Carlo; Rameil, Steffen; Sander, Peter; Koromyslova, Anna

    2016-01-01

    ABSTRACT Human noroviruses are the dominant cause of outbreaks of acute gastroenteritis. These viruses are usually detected by molecular methods, including reverse transcriptase PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Human noroviruses are genetically and antigenically diverse, with two main genogroups that are further subdivided into over 40 different genotypes. During the past decade, genogroup 2 genotype 4 (GII.4) has dominated in most countries, but recently, viruses belonging to GII.17 have increased in prevalence in a number of countries. A number of commercially available ELISAs and lateral flow immunoassays were found to have lower sensitivities to the GII.17 viruses, indicating that the antibodies used in these methods may not have a high level of cross-reactivity. In this study, we developed a rapid Nanobody-based lateral flow immunoassay (Nano-immunochromatography [Nano-IC]) for the detection of human norovirus in clinical specimens. The Nano-IC assay detected virions from two GII.4 norovirus clusters, which included the current dominant strain and a novel variant strain. The Nano-IC method had a sensitivity of 80% and specificity of 86% for outbreak specimens. Norovirus virus-like particles (VLPs) representing four genotypes (GII.4, GII.10, GII.12, and GII.17) could be detected by this method, demonstrating the potential in clinical screening. However, further modifications to the Nano-IC method are needed in order to improve this sensitivity, which may be achieved by the addition of other broadly reactive Nanobodies to the system. IMPORTANCE We previously identified a Nanobody (termed Nano-85) that bound to a highly conserved region on the norovirus capsid. In this study, the Nanobody was biotinylated and gold conjugated for a lateral flow immunoassay (termed Nano-IC). We showed that the Nano-IC assay was capable of detecting at least four antigenically distinct GII genotypes, including the newly emerging GII.17. In the clinical

  11. Engineering bacterial surface displayed human norovirus capsid proteins: A novel system to explore interaction between norovirus and ligands

    Directory of Open Access Journals (Sweden)

    Mengya eNiu

    2015-12-01

    Full Text Available Human noroviruses (HuNoVs are major contributors to acute nonbacterial gastroenteritis outbreaks. Many aspects of HuNoVs are poorly understood due to both the current inability to culture HuNoVs, and the lack of efficient small animal models. Surrogates for HuNoVs, such as recombinant viral like particles (VLPs expressed in eukaryotic system or P particles expressed in prokaryotic system, have been used for studies in immunology and interaction between the virus and its receptors. However, it is difficult to use VLPs or P particles to collect or isolate potential ligands binding to these recombinant capsid proteins. In this study, a new strategy was used to collect HuNoVs binding ligands through the use of ice nucleation protein (INP to display recombinant capsid proteins of HuNoVs on bacterial surfaces. The viral protein-ligand complex could be easily separated by a low speed centrifugation step. This system was also used to explore interaction between recombinant capsid proteins of HuNoVs and their receptors. In this system, the VP1 capsid encoding gene (ORF2 and the protruding domain (P domain encoding gene (3’ terminal fragment of ORF2 of HuNoVs GI.1 and GII.4 were fused with 5’ terminal fragment of ice nucleation protein encoding gene (inaQn. The results demonstrated that the recombinant VP1 and P domains of HuNoVs were expressed and anchored on the surface of Escherichia coli BL21 cells after the bacteria were transformed with the corresponding plasmids. Both cell surface displayed VP1 and P domains could be recognized by HuNoVs specific antibodies and interact with the viral histo-blood group antigens receptors. In both cases, displayed P domains had better binding abilities than VP1. This new strategy of using displayed HuNoVs capsid proteins on the bacterial surface could be utilized to separate HuNoVs binding components from complex samples, to investigate interaction between the virus and its receptors, as well as to develop an

  12. Evaluación morfológica de brotes regenerados de callos de arroz (variedad IACuba-28 resistentes a higromicina Morphological Evaluation of Shoots Regenerated from Hygromycin-Resistant Rice Callus (cv IACuba-28

    Directory of Open Access Journals (Sweden)

    Hernández Díaz Carlos Alberto

    2007-07-01

    Full Text Available Se estableció un sistema de evaluación de brotes de arroz regenerados de callos resistentes a higromicina, que permitió relacionar las características morfológicas de dichos brotes con su resistencia al antibiótico. Callos embriogénicos de arroz se transformaron con Agrobacterium tumefaciens (EHA105/ pCAMBIA1300, con el gen de la higromicina-fosfotransferasa como marcador de selección. Después de dos semanas en medio de cultivo con higromicina, los callos resistentes fueron transferidos a regeneración. Durante 30 días se realizaron extracciones sucesivas de brotes emitidos de los callos, en seis intervalos de cinco días cada uno. Estos brotes se clasificaron según su morfología en: clase I – brote vigoroso con una estructura bipolar típica, de ápice y raíz con longitudes proporcionales; clase II – brote con raíz pequeña respecto al ápice, o sin raíz; clase III – brote con alteraciones fenotípicas, albinismo, hojas muy anchas o enrolladas. Los brotes clasificados se transfirieron a medio MS con higromicina para evaluar su viabilidad. Los de clase I, que predominaron en las primeras extracciones, presentaron la mayor viabilidad durante el enraizamiento y crecimiento del follaje. En las últimas dos extracciones ocurrió una drástica reducción de los brotes clase I, y aumentaron los de clases II y III, simultáneamente disminuyó la viabilidad de estos últimos en MS con higromicina. Este resultado puede aplicarse para mejorar la eficiencia de obtención de plantas transgénicas de arroz en estas condiciones, debido a que precisa el momento óptimo para lograr brotes con características morfológicas normales y que sean resistentes a higromicina.An evaluation system based on the morphological characteristics of regenerated hygromycin-resistant rice callus shoots was established for correlating such characteristics with shoot viability on hygromycin. Embryogenic rice calli were transformed by Agrobacterium tumefaciens

  13. Inactivation of norovirus surrogates on surfaces and raspberries by steam-ultrasound treatment

    DEFF Research Database (Denmark)

    Schultz, Anna Charlotte; Uhrbrand, Katrine; Nørrung, Birgit

    2012-01-01

    Human disease outbreaks caused by norovirus (NoV) following consumption of contaminated raspberries are an increasing problem. An efficient method to decontaminate the fragile raspberries and the equipment used for processing would be an important step in ensuring food safety. A potential surface...... treatment that combines pressurized steam and high-power ultrasound (steam-ultrasound) was assessed for its efficacy to inactivate human NoV surrogates: coliphage (MS2), feline calicivirus (FCV), and murine norovirus (MNV) inoculated on plastic surfaces and MS2 inoculated on fresh raspberries. The amounts......, respectively; while a 3.7-log (99.9%) reduction of MNV was reached after 3 s of treatment. However, on fresh raspberries only a 1-log reduction (∼89%) of MS2 could be achieved after 1 s of treatment, at which point damage to the texture of the fresh raspberries was evident. Increasing treatment time (0 to 3 s...

  14. Waterborne norovirus outbreak in a municipal drinking-water supply in Sweden.

    Science.gov (United States)

    Riera-Montes, M; Brus Sjölander, K; Allestam, G; Hallin, E; Hedlund, K-O; Löfdahl, M

    2011-12-01

    During Easter 2009, almost 200 people resident in a small Swedish village fell ill with gastrointestinal symptoms. We conducted a retrospective cohort study and a molecular investigation in order to identify the source of the outbreak. Residents living in households connected to the public water network were at an increased risk of developing disease (relative risk 4·80, 95% confidence interval 1·68-13·73) compared to those with no connection to the public network. Norovirus genotype GI.3 was identified in stool samples from six patients and in a sample from the public water network. Contamination of one of the wells supplying the public water network was thought to be the source of the outbreak. This is a description of a norovirus outbreak linked to a municipal drinking-water supply in Sweden. Information from epidemiological and molecular investigations is of utmost importance to guide outbreak control measures and to prevent future outbreaks.

  15. Norovirus epidemiology in community and health care settings and association with patient age, denmark

    DEFF Research Database (Denmark)

    Franck, Kristina T; Fonager, Jannik; Ersbøll, Annette K;

    2014-01-01

    . In community and health care settings, we found an association between infection with GII.4 and increasing age. Norovirus GII.4 predominated in patients ≥60 years of age and in health care settings. A larger proportion of children than adults were infected with NoV GII.3 or GII.P21. Susceptibility to No......Norovirus (NoV) is a major cause of gastroenteritis. NoV genotype II.4 (GII.4) is the predominant genotype in health care settings but the reason for this finding is unknown. Stool samples containing isolates with a known NoV genotype from 2,109 patients in Denmark (patients consulting a general...... practitioner or outpatient clinic, inpatients, and patients from foodborne outbreaks) were used to determine genotype distribution in relation to age and setting. NoV GII.4 was more prevalent among inpatients than among patients in community settings or those who became infected during foodborne outbreaks...

  16. Inactivation Kinetics and Mechanism of a Human Norovirus Surrogate on Stainless Steel Coupons via Chlorine Dioxide Gas.

    Science.gov (United States)

    Yeap, Jia Wei; Kaur, Simran; Lou, Fangfei; DiCaprio, Erin; Morgan, Mark; Linton, Richard; Li, Jianrong

    2015-10-16

    Acute gastroenteritis caused by human norovirus is a significant public health issue. Fresh produce and seafood are examples of high-risk foods associated with norovirus outbreaks. Food contact surfaces also have the potential to harbor noroviruses if exposed to fecal contamination, aerosolized vomitus, or infected food handlers. Currently, there is no effective measure to decontaminate norovirus on food contact surfaces. Chlorine dioxide (ClO2) gas is a strong oxidizer and is used as a decontaminating agent in food processing plants. The objective of this study was to determine the kinetics and mechanism of ClO2 gas inactivation of a norovirus surrogate, murine norovirus 1 (MNV-1), on stainless steel (SS) coupons. MNV-1 was inoculated on SS coupons at the concentration of 10(7) PFU/coupon. The samples were treated with ClO2 gas at 1, 1.5, 2, 2.5, and 4 mg/liter for up to 5 min at 25°C and a relative humidity of 85%, and virus survival was determined by plaque assay. Treatment of the SS coupons with ClO2 gas at 2 mg/liter for 5 min and 2.5 mg/liter for 2 min resulted in at least a 3-log reduction in MNV-1, while no infectious virus was recovered at a concentration of 4 mg/liter even within 1 min of treatment. Furthermore, it was found that the mechanism of ClO2 gas inactivation included degradation of viral protein, disruption of viral structure, and degradation of viral genomic RNA. In conclusion, treatment with ClO2 gas can serve as an effective method to inactivate a human norovirus surrogate on SS contact surfaces.

  17. Regeneración Natural de la Guadua (Guadua Angustifolia Kunt por Activación de las Yemas del Rizoma.

    Directory of Open Access Journals (Sweden)

    Arbeláez Arce Anacilia

    1996-09-01

    Full Text Available La regeneración natural de los bambúes ocurre estacionalmente y es el resultado de dos estrategias reproductivas: la sexual, por medio de la producción de semilla y la asexual por la activación de l las yemas del rizoma. El estudio de la última estrategia, constituye el objetivo de la presente investigación. El registro de datos se llevó a cabo desde Julio de 1991 hasta Julio de 1995, en la plantación natural de Guadua angustifolia, existente en el Centro Agropecuario Cotové, de la Universidad Nacional, localizado en el municipio de Santafé de Antioquia, a 550 msnm, temperatura promedia anual 26.3 °C y 1244 mm de precipitación promedia anual. Corresponde a la zona de vida de Bosque seco Tropical (bs-T. La vida productiva del rizoma es de cuatro (4 años y el ciclo vegetativo superior a los diez (10 años. Un rizoma de Guadua angustifolia produce, con características similares en el diámetro y por consiguiente en altura, de uno a cuatro brotes, tres de ellos pueden producirse simultáneamente. Los brotes emergen del suelo a una distancia promedia de 1.22 m. del rizoma madre y forman un ángulo horizontal de 450 a 900 entre ellos. La producción máxima se dá en rizomas de 1 y/o 2 años. La producción anual de brotes es el 21 % de la población global.

  18. Genetic diversity among food-borne and waterborne norovirus strains causing outbreaks in Sweden.

    Science.gov (United States)

    Lysén, Maria; Thorhagen, Margareta; Brytting, Maria; Hjertqvist, Marika; Andersson, Yvonne; Hedlund, Kjell-Olof

    2009-08-01

    A total of 101 food-borne and waterborne outbreaks that were caused by norovirus and that resulted in more than 4,100 cases of illness were reported to the Swedish Institute for Infectious Disease Control from January 2002 to December 2006. Sequence and epidemiological data for isolates from 73 outbreaks were analyzed. In contrast to health care-related outbreaks, no clear seasonality could be observed. Sequence analysis showed a high degree of genetic variation among the noroviruses detected. Genogroup II (GII) viruses were detected in 70% of the outbreaks, and of those strains, strains of GII.4 were the most prevalent and were detected in 25% of all outbreaks. The GII.4 variants detected in global outbreaks in health care settings during 2002, 2004, and 2006 were also found in the food-borne outbreaks. GI strains totally dominated as the cause of water-related (drinking and recreational water) outbreaks and were found in 12 of 13 outbreaks. In 14 outbreaks, there were discrepancies among the polymerase and capsid genotype results. In four outbreaks, the polymerase of the recombinant GII.b virus occurred together with the GII.1 or GII.3 capsids, while the GII.7 polymerase occurred together with the GII.6 and GII.7 capsids. Mixed infections were observed in six outbreaks; four of these were due to contaminated water, and two were due to imported frozen berries. Contaminated food and water serve as important reservoirs for noroviruses. The high degree of genetic diversity found among norovirus strains causing food-borne and waterborne infections stresses the importance of the use of broad reaction detection methods when such outbreaks are investigated.

  19. Recombinant norovirus-specific scFv inhibit virus-like particle binding to cellular ligands

    Directory of Open Access Journals (Sweden)

    Hardy Michele E

    2008-01-01

    Full Text Available Abstract Background Noroviruses cause epidemic outbreaks of gastrointestinal illness in all age-groups. The rapid onset and ease of person-to-person transmission suggest that inhibitors of the initial steps of virus binding to susceptible cells have value in limiting spread and outbreak persistence. We previously generated a monoclonal antibody (mAb 54.6 that blocks binding of recombinant norovirus-like particles (VLP to Caco-2 intestinal cells and inhibits VLP-mediated hemagglutination. In this study, we engineered the antigen binding domains of mAb 54.6 into a single chain variable fragment (scFv and tested whether these scFv could function as cell binding inhibitors, similar to the parent mAb. Results The scFv54.6 construct was engineered to encode the light (VL and heavy (VH variable domains of mAb 54.6 separated by a flexible peptide linker, and this recombinant protein was expressed in Pichia pastoris. Purified scFv54.6 recognized native VLPs by immunoblot, inhibited VLP-mediated hemagglutination, and blocked VLP binding to H carbohydrate antigen expressed on the surface of a CHO cell line stably transfected to express α 1,2-fucosyltransferase. Conclusion scFv54.6 retained the functional properties of the parent mAb with respect to inhibiting norovirus particle interactions with cells. With further engineering into a form deliverable to the gut mucosa, norovirus neutralizing antibodies represent a prophylactic strategy that would be valuable in outbreak settings.

  20. Nosocomial outbreak of norovirus gastroenteritidis with unusual clinical-epidemiological features

    Directory of Open Access Journals (Sweden)

    Marco Arosio

    2008-12-01

    Full Text Available Literature reports about Norovirus outbreaks, especially in hospitals, have accumulated in the past years, including patients and health workers.This report describes a small outbreak by Norovirus which occurred in USC Urology with unusual clinical-epidemiological features.The clinical course was unusual, as it presented no vomiting and duration of diarrhoea was unusually long (4-6 days with the lack of involvement of health workers.The search for the virus was done with immunoassay method RIDASCREEN 2a generation on 11/19 patients (58% with gastroenteritis symptoms, and 3/11 samples (27% were positive. The molecular investigation by RT/PCR with diagnostic primers JV12 and JV13 on the polymerase region, carried out at the Istituto Superiore di Sanità, Rome, gave negative results while the RT/PCR using primers GIISKR and GIISKF, which amplify a fragment of the capsid region, was positive in 4/11 samples (36% showing a correlation of 2/4 samples (50% with RIDASCREEN immunoassay test. Our observations confirm the usefulness of immunoassay tests and the need to extend the molecular methods using different diagnostic primers. In outbreaks of gastroenteritis the microbiologist should consider the detection of Norovirus in diagnostic routine, as a positive result requires prevention measures to avoid also the spreading by droplets when vomiting is present.

  1. Norovirus in bivalve molluscs: a study of the efficacy of the depuration system

    Directory of Open Access Journals (Sweden)

    Giovanni Savini

    2009-12-01

    Full Text Available Noroviruses are the most common viral agents of acute gastroenteritis in humans and are often associated with the consumption of either fresh or undercooked live bivalve molluscs. The aim of the study was to evaluate the efficacy of the water depuration systems in the presence of Norovirus contamination A total of 96 shellfish samples was examined by reverse transcriptase-polymerase chain reaction, as follows: 58 mussel samples (Mytilus galloprovincialis, 35 Manila clam samples (Tapes decussatus and 3 Pacific oyster samples (Crassostrea gigas. Of these, 67 were collected before and 29 following depuration. Viral RNA was detected in one of the 67 non-depurated samples examined (1.5%; 95% confidence interval: 0.36-7.92% and in one of the 29 depurated samples (3.4%; 95% confidence interval: 0.82-17.22%. There were no statistically significant differences between depurated and non-depurated samples which indicated that the purifying systems in place were not able to remove Norovirus contamination from the live bivalve molluscs.

  2. A large common-source outbreak of norovirus gastroenteritis in a hotel in Singapore, 2012.

    Science.gov (United States)

    Raj, P; Tay, J; Ang, L W; Tien, W S; Thu, M; Lee, P; Pang, Q Y; Tang, Y L; Lee, K Y; Maurer-Stroh, S; Gunalan, V; Cutter, J; Goh, K T

    2017-02-01

    An outbreak of gastroenteritis affected 453 attendees (attack rate 28·5%) of six separate events held at a hotel in Singapore. Active case detection, case-control studies, hygiene inspections and microbial analysis of food, environmental and stool samples were conducted to determine the aetiology of the outbreak and the modes of transmission. The only commonality was the food, crockery and cutlery provided and/or handled by the hotel's Chinese banquet kitchen. Stool specimens from 34 cases and 15 food handlers were positive for norovirus genogroup II. The putative index case was one of eight norovirus-positive food handlers who had worked while they were symptomatic. Several food samples and remnants tested positive for Escherichia coli or high faecal coliforms, aerobic plate counts and/or total coliforms, indicating poor food hygiene. This large common-source outbreak of norovirus gastroenteritis was caused by the consumption of contaminated food and/or contact with contaminated crockery or cutlery provided or handled by the hotel's Chinese banquet kitchen.

  3. Application of porcine gastric mucin-conjugated magnetic beads and polyethylene glycol goncentration and detection of human noroviruses from green onion and grape

    Science.gov (United States)

    Objective: To set up detection methods for norovirus in fruits and vegetables by using porcine gastric mucin-conjugated magnetic beads (PGM-MB) and polyethylene glycol 8000 (PEG8000) concentrating and detecting the norovirus in green onion and grape. Methods: The highest virus dilution given a posit...

  4. Evaluation of a rapid immunochromatographic assay for the detection of rotavirus, norovirus and adenovirus from children hospitalized with acute watery diarrhea.

    Science.gov (United States)

    Kas, Monalisa P; Maure, Tobias; Soli, Kevin W; Umezaki, Masahiro; Morita, Ayako; Bebes, Sauli; Jonduo, Marinjho H; Larkins, Jo-Ann; Luang-Suarkia, Dagwin; Siba, Peter M; Greenhill, Andrew R; Horwood, Paul F

    2013-01-01

    We evaluated the IP-Triple I immunochromatographic rapid test for the detection of rotavirus, norovirus and adenovirus using stool samples from children with diarrhoea. The detection of norovirus and adenovirus was poor compared to polymerase chain reaction assays. However, high sensitivity (92%) and specificity (99%) were obtained for the detection of rotavirus.

  5. Real-time detection of noroviruses in surface water by use of a broadly reactive nucleic acid sequence-based amplification assay.

    NARCIS (Netherlands)

    Rutjes, Saskia A; Berg, Harold H J L van den; Lodder, Willemijn J; Roda Husman, Ana Maria de

    2006-01-01

    Noroviruses are the most common agents causing outbreaks of viral gastroenteritis. Outbreaks originating from contaminated drinking water and from recreational waters have been described. Due to a lack of cell culture systems, noroviruses are detected mostly by molecular methods. Molecular detection

  6. The efficacy of X-ray does on murine norovirus-1 (MNV-1) in pure culture, half-shell oyster, salmon sushi, and tuna salad

    Science.gov (United States)

    In this investigation, we determined the efficacy of X-ray doses on reducing a human norovirus (HuNoV) surrogate [murine norovirus-1 (MNV-1)] in pure culture, half-shell oyster, salmon sushi and tuna salad. The pure culture (phosphate-buffer saline, pH 7.4), half-shell oyster, salmon sushi and tuna ...

  7. Validation of a norovirus multiplex real-time RT-PCR assay for the detection of norovirus GI and GII from faeces samples.

    LENUS (Irish Health Repository)

    Jones, S

    2011-01-01

    Norovirus is a leading cause of infectious non-bacterial gastroenteritis. The virus is highly contagious and has multiple modes of transmission, presenting a growing challenge to hospital-based healthcare. In this study, a total of 120 stool samples are tested for the presence of norovirus GI and GII by the Roche two-step Lightcycler 2.0 assay incorporating primers and probes produced by TIB Molbiol, and the results are compared with results from the National Virus Reference Laboratory. The Roche\\/TIB Molbiol assay produced 51 positive results and 69 negative results. Discrepancy analysis was performed for six conflicting results using a second real-time polymerase chain reaction (PCR) assay (Roche\\/TIB Molbiol) and this confirmed that four of the five discrepant positive results were true positives. A single discrepant negative result generated by the Roche assay remained negative using the second assay. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated to be 98%, 98.6%, 98.0% and 98.6%, respectively. Melting curve analysis was used to differentiate genogroups I and II and this showed that 92% of strains belonged to genogroup II.

  8. Detecting the norovirus season in Sweden using search engine data--meeting the needs of hospital infection control teams.

    Science.gov (United States)

    Edelstein, Michael; Wallensten, Anders; Zetterqvist, Inga; Hulth, Anette

    2014-01-01

    Norovirus outbreaks severely disrupt healthcare systems. We evaluated whether Websök, an internet-based surveillance system using search engine data, improved norovirus surveillance and response in Sweden. We compared Websök users' characteristics with the general population, cross-correlated weekly Websök searches with laboratory notifications between 2006 and 2013, compared the time Websök and laboratory data crossed the epidemic threshold and surveyed infection control teams about their perception and use of Websök. Users of Websök were not representative of the general population. Websök correlated with laboratory data (b = 0.88-0.89) and gave an earlier signal to the onset of the norovirus season compared with laboratory-based surveillance. 17/21 (81%) infection control teams answered the survey, of which 11 (65%) believed Websök could help with infection control plans. Websök is a low-resource, easily replicable system that detects the norovirus season as reliably as laboratory data, but earlier. Using Websök in routine surveillance can help infection control teams prepare for the yearly norovirus season.

  9. Identification and Characterization of Single-Chain Antibodies that Specifically Bind GI Noroviruses

    Science.gov (United States)

    Hurwitz, Amy M.; Huang, Wanzhi; Kou, Baijun; Estes, Mary K.; Atmar, Robert L.; Palzkill, Timothy

    2017-01-01

    Norovirus infections commonly lead to outbreaks of acute gastroenteritis and spread quickly, resulting in many health and economic challenges prior to diagnosis. Rapid and reliable diagnostic tests are therefore essential to identify infections and to guide the appropriate clinical responses at the point-of-care. Existing tools, including RT-PCR and enzyme immunoassays, pose several limitations based on the significant time, equipment and expertise required to elicit results. Immunochromatographic assays available for use at the point-of-care have poor sensitivity and specificity, especially for genogroup I noroviruses, thus requiring confirmation of results with more sensitive testing methods. Therefore, there is a clear need for novel reagents to help achieve quick and reliable results. In this study, we have identified two novel single-chain antibodies (scFvs)—named NJT-R3-A2 and NJT-R3-A3—that effectively detect GI.1 and GI.7 virus-like particles (VLPs) through selection of a phage display library against the P-domain of the GI.1 major capsid protein. The limits of detection by each scFv for GI.1 and GI.7 are 0.1 and 0.2 ng, and 6.25 and 25 ng, respectively. They detect VLPs with strong specificity in multiple diagnostic formats, including ELISAs and membrane-based dot blots, and in the context of norovirus-negative stool suspensions. The scFvs also detect native virions effectively in norovirus-positive clinical stool samples. Purified scFvs bind to GI.1 and GI.7 VLPs with equilibrium constant (KD) values of 27 nM and 49 nM, respectively. Overall, the phage-based scFv reagents identified and characterized here show utility for detecting GI.1 and GI.7 noroviruses in multiple diagnostic assay formats with strong specificity and sensitivity, indicating promise for integration into existing point-of-care tests to improve future diagnostics. PMID:28095447

  10. Electronic Outbreak Surveillance in Germany: A First Evaluation for Nosocomial Norovirus Outbreaks

    Science.gov (United States)

    Hauri, Anja M.; Westbrock, Hans-Jürgen; Claus, Herman; Geis, Steffen; Giernat, Siegfried; Forβbohm, Michael; Uphoff, Helmut

    2011-01-01

    Background In Germany, surveillance for infectious disease outbreaks is integrated into an electronic surveillance system. For 2007, the national surveillance database contains case-based information on 201,224 norovirus cases, three-quarters of which are linked to outbreaks. We evaluated the data quality of the national database in reflecting nosocomial norovirus outbreak (NNO) data available in 19 Hessian local public health authorities (LPHAs) and the influence of differences between LPHA's follow-up procedures for laboratory notifications of Norovirus positive stool samples on outbreak underascertainment. Methods Data on NNO beginning in 2007 and notified to the 19 LPHAs were extracted from the national database, investigated regarding internal validity and compared to data collected from LPHAs for a study on NNO control. LPHAs were questioned whether they routinely contacted all persons for whom a laboratory diagnosis of norovirus infection was notified. The number of outbreaks per 1,000 hospital beds and the number of cases within NNOs for acute care and rehabilitation hospitals were compared between counties with and without complete follow-up. Results The national database contained information on 155 NNOs, including 3,115 cases. Cases were missed in the national database in 58 (37%) of the outbreaks. Information on hospitalisation was incorrect for an estimated 47% of NNO cases. Information on county of infection was incorrect for 24% (199/820) of cases being forwarded between LPHAs for data entry. Reported NNO incidence and number of NNO cases in acute care hospitals was higher in counties with complete follow-up (incidence-rate ratio (IRR) 2.7, 95% CI 1.4–5.7, p-value 0.002 and IRR 2.1, 95% CI 1.9–2.4, p-value 0.001, respectively). Conclusions Many NNOs are not notified by hospitals and differences in LPHA procedures have an impact on the number of outbreaks captured in the surveillance system. Forwarding of case-by-case data on Norovirus outbreak

  11. Evaluación de la definición de caso probable de dengue clásico durante el brote de dengue en Lima, 2005

    Directory of Open Access Journals (Sweden)

    José Juárez S

    2005-07-01

    Full Text Available Objetivos: Evaluar la utilidad diagnóstica de la definición de caso probable de dengue clásico (DCPDC para la identificación de casos definitivos, durante el brote en el distrito de Comas, abril - mayo 2005. Materiales y métodos: Estudio observacional, analítico, no controlado de corte transversal. Se incluyeron pacientes procedentes de Comas que en el periodo de estudio presentaron sospecha de dengue y con resultados de aislamiento viral o ELISA IgM, según el tiempo de enfermedad (4 ó e5 días respectivamente realizados en el Instituto Nacional de Salud. Se determinó la sensibilidad (S, especificidad (E, valor predictivo positivo (VPP y negativo (VPN de la DCPDC y de los síntomas que la conforman, tomando como prueba de oro al aislamiento viral o ELISA IgM. Resultados:Se incluyeron 316 pacientes, de los cuales se confirmaron 137 (43,4% casos de dengue. Se detectaron 60 pacientes mediante aislamiento viral, la DCPDC en pacientes con cuatro o menos días de enfermedad presentó una S=85%, E=13,40%, VPP=13,18%, VPN= 74,29%. Se detectaron 77 pacientes con cinco o más días de enfermedad con IgM ELISA, la DCPDC en este grupo presentó S= 68,42, E= 16,28, VPP= 68,42, VPN= 46,67. Conclusiones: La DCPDC aplicada en el brote de dengue en Comas, al igual que los síntomas individuales que la conforman es sensible, pero poco específico.

  12. Separate norovirus outbreaks linked to one source of imported frozen raspberries by molecular analysis, Denmark, 2010–2011

    DEFF Research Database (Denmark)

    Müller, L.; Schultz, Anna Charlotte; Fonager, J.

    2015-01-01

    Norovirus outbreaks occur frequently in Denmark and it can be difficult to establish whether apparently independent outbreaks have the same origin. Here we report on six outbreaks linked to frozen raspberries, investigated separately over a period of 3 months. Norovirus from stools were sequence...... capsid P2 region. In one outbreak at a hospital canteen, frozen raspberries was associated with illness by cohort investigation (relative risk 6·1, 95% confidence interval 3·2–11). Bags of raspberries suspected to be the source were positive for genogroup I and II noroviruses, one typable virus...... was genotype GI.6 (capsid). These molecular investigations showed that the apparently independent outbreaks were the result of one contamination event of frozen raspberries. The contaminated raspberries originated from a single producer in Serbia and were originally not considered to belong to the same batch...

  13. por valores

    Directory of Open Access Journals (Sweden)

    Jazmín Díaz-Barrios

    2005-01-01

    Full Text Available La era actual se caracteriza por una búsqueda de la identidad del hombre, donde el pivote del cambio organizacional es el individuo; cambiar en este entorno depende, en gran medida, de los valores que imperen en la cultura de la organización. Este trabajo documental intenta identificar aquellos valores, condición sine-qua-non, para el logro de los objetivos de cambio y analizarlos a fin de determinar sus indicadores, con el objeto de presentar una herramienta a las organizaciones que les facilite adaptarse a los nuevos tiempos. Se encontró que los valores: Delegación, Comunicación, Colaboración, Participación y Aprendizaje, son esenciales en los cambios integrales de esta era. Se determinaron 20 indicadores de su presencia. Se concluye que con esta información cada ente puede elaborar instrumentos que le permitan saber si los valores requeridos están presentes y en caso contrario tomar decisiones que alineen a la organización alrededor de los valores humanistas planteados, incrementando así las posibilidades de éxito en el proceso de cambio y por ende, las posibilidades de supervivencia en esta nueva época.

  14. A Membrane-Based Electro-Separation Method (MBES) for Sample Clean-Up and Norovirus Concentration.

    Science.gov (United States)

    Kang, Wei; Cannon, Jennifer L

    2015-01-01

    Noroviruses are the leading cause of acute gastroenteritis and foodborne illnesses in the United States. Enhanced methods for detecting noroviruses in food matrices are needed as current methods are complex, labor intensive and insensitive, often resulting in inhibition of downstream molecular detection and inefficient recovery. Membrane-based electro-separation (MBES) is a technique to exchange charged particles through a size-specific dialysis membrane from one solution to another using electric current as the driving force. Norovirus has a net negative surface charge in a neutrally buffered environment, so when placed in an electric field, it moves towards the anode. It can then be separated from the cathodic compartment where the sample is placed and then collected in the anodic compartment for downstream detection. In this study, a MBES-based system was designed, developed and evaluated for concentrating and recovering murine norovirus (MNV-1) from phosphate buffer. As high as 30.8% MNV-1 migrated from the 3.5 ml sample chamber to the 1.5 ml collection chamber across a 1 μm separation membrane when 20 V was applied for 30 min using 20 mM sodium phosphate with 0.01% SDS (pH 7.5) as the electrolyte. In optimization of the method, weak applied voltage (20 V), moderate duration (30 min), and low ionic strength electrolytes with SDS addition were needed to increase virus movement efficacy. The electric field strength of the system was the key factor to enhance virus movement, which could only be improved by shortening the electrodes distance, instead of increasing system applied voltage because of virus stability. This study successfully demonstrated the norovirus mobility in an electric field and migration across a size-specific membrane barrier in sodium phosphate electrolyte. With further modification and validation in food matrixes, a novel, quick, and cost-effective sample clean-up technique might be developed to separate norovirus particles from food

  15. Acute myositis associated with concurrent infection of rotavirus and norovirus in a 2-year-old girl

    Directory of Open Access Journals (Sweden)

    Kei Yamamoto

    2015-09-01

    Full Text Available Rotavirus and norovirus are common pathogens associated with gastroenteritis in children. Although rotavirus occasionally induces central nervous system disease, only 3 cases with rotavirus-induced acute myositis have been reported in the English literature. We recently treated a female patient with acute myositis associated with gastroenteritis induced by concurrent infection with rotavirus and norovirus. Having suffered from gastroenteritis for 3 days, she suddenly developed myositis affecting her lower extremities with concomitant creatine kinase elevation. Herein, we present our patient and review the previous cases including those reported in the Japanese literature.

  16. The viral polymerase inhibitor 2'-C-methylcytidine inhibits Norwalk virus replication and protects against norovirus-induced diarrhea and mortality in a mouse model.

    Science.gov (United States)

    Rocha-Pereira, Joana; Jochmans, Dirk; Debing, Yannick; Verbeken, Erik; Nascimento, Maria S J; Neyts, Johan

    2013-11-01

    Human noroviruses are a major cause of food-borne illness, accountable for 50% of all-etiologies outbreaks of acute gastroenteritis (in both developing and developed countries). There is no vaccine or antiviral drug for the prophylaxis or treatment of norovirus-induced gastroenteritis. We recently reported the inhibitory effect of 2'-C-methylcytidine (2CMC), a hepatitis C virus polymerase inhibitor, on the in vitro replication of murine norovirus (MNV). Here we evaluated the inhibitory effect of 2CMC on in vitro human norovirus replication through a Norwalk virus replicon model and in a mouse model by using AG129 mice orally infected with MNV. Survival, weight, and fecal consistency were monitored, and viral loads in stool samples and organs were quantified. Intestines were examined histologically. 2CMC reduced Norwalk virus replicon replication in a dose-dependent manner and was able to clear cells of the replicon. Treatment of MNV-infected AG129 mice with 2CMC (i) prevented norovirus-induced diarrhea; (ii) markedly delayed the appearance of viral RNA and reduced viral RNA titers in the intestine, mesenteric lymph nodes, spleen, lungs, and stool; (iii) completely prevented virus-induced mortality; and (iv) resulted in protective immunity against a rechallenge. We demonstrate for the first time that a small-molecule inhibitor of norovirus replication protects from virus-induced disease and mortality in a relevant animal model. These findings pave the way for the development of potent and safe antivirals as prophylaxis and therapy of norovirus infection.

  17. Epidemiología de las infecciones por arena y hantavirus del Nuevo Mundo

    Directory of Open Access Journals (Sweden)

    Noemí Pini

    2010-04-01

    Full Text Available En la última década el reconocimiento de un número de brotes o casos aislados de fiebres hemorrágicas virales (FHV ha alertado sobre la amenaza de estas enfermedades como potenciales infecciones emergentes. El concepto de FHV resulta relativamente moderno, si se considera que muchas de las enfermedades que agrupamos bajo este síndrome eran claramente conocidas por el hombre desde muchos siglos atrás (1. Su carácter de infecciones emergentes es, sin duda, verdadero si se tiene en cuenta que su reconocimiento se ha incrementado significativamente. Observadas, sin embargo, desde el ángulo de los agentes que las producen, el concepto de “nuevo” no es tal: los virus causantes de estas enfermedadeses probable que sean más antiguos que nuestra propia especie humana.

  18. Descripción de un brote de dermatofitosis en bovinos en el trópico mexicano - Report of a dermatophytosis outbreak in cattle in the mexican tropic.

    Directory of Open Access Journals (Sweden)

    Luis Jorge, García Márquez

    2012-07-01

    Full Text Available ResumenEn este informe se describen los hallazgos clínicos y patológicos de un brote de dermatofitosis en bovinos (Suizo/Cebú en la zona tropical de Tomatlán, Jalisco, México.AbstractThis report describes the clinical and pathological findings of a dermatophytosis outbreak in bovines (Swizz/Zebu in the tropical zone of Tomatlan, Jalisco, Mexico.

  19. Molecular characterisation of noroviruses detected in mussels (Mytilus galloprovincialis) from harvesting areas in Slovenia.

    Science.gov (United States)

    Henigman, Urška; Biasizzo, Majda; Vadnjal, Stanka; Toplak, Ivan; Gombač, Mitja; Steyer, Andrej; Poljšak Prijatelj, Mateja; Ambrožič, Mateja; Fonda, Irena; Kirbiš, Andrej; Barlič-Maganja, Darja

    2015-04-01

    Noroviruses are a leading cause of viral gastroenteritis in humans and are responsible for many outbreaks worldwide. Mussels are one of the most important foodstuffs connected with norovirus outbreaks, also resulting in multinational dimensions. Two hundred and thirty-eight (238) samples of mussels (Mytilus galloprovincialis) were collected in periods between the years 2006-2008 and 2010-2012 to study the prevalence of noroviruses (NoVs) from harvesting areas along the Adriatic coast of Slovenia. Between 2006 and 2008, 9.1% to 24.6% of mussel samples tested by specific GI and/or GII real-time RT-PCR methods were found to be positive for NoVs while between 2010 and 2012 the percentage of NoV positive samples varied from 12.5% to 22.2%. At the nucleotide level within the RdRp gene fragment the genetic diversity of NoVs detected in mussels ranged between 78.8-81.0% nucleotide identity among GII strains (92.1-99.6% within the GII.P4 genotype), 100% nucleotide identity among GI and 58.4-60.2% among GI and GII strains. Nine of the NoV strains detected from mussels were genotyped as GII.4, while two samples were within GI.P2 and one was a positive sample within genotype GII.P21. This study confirmed that mussels are a potential source of the NoV infection. The detected NoVs share the same topology on the phylogenetic tree within the NoV strains detected in water samples and human patients, not only from Slovenia but also from many different countries worldwide. We can assume that mussels in harvesting areas are not only contaminated from the surrounding area but also by contaminated water and sewage from large transport ships, which are regularly present in the area.

  20. Boerhaave's syndrome and tension pneumothorax secondary to Norovirus induced forceful emesis

    DEFF Research Database (Denmark)

    Venø, Søren; Eckardt, Jens

    2013-01-01

    Boerhaave's syndrome or spontaneous esophageal perforation is a rare condition, with high mortality. We describe a case of Boerhaave's syndrome presenting with tension pneumothorax. The patient was infected with Norovirus and developed Boerhaave's syndrome, initially thought to be gastroenteritis...... but later developing with tension pneumothorax, and mediastinitis caused by esophageal perforation. The patient was treated with thoracotomy with primary suture and oesophageal stent placement. He had a long period of recovery and was discharged after 98 days. Boerhaaves syndrome is often delayed and must...

  1. Production of Brazilian human norovirus VLPs and comparison of purification methods

    Directory of Open Access Journals (Sweden)

    Thais Alves da Costa Lamounier

    2015-01-01

    Full Text Available AbstractNoroviruses (NVs are responsible for most cases of human nonbacterial gastroenteritis worldwide. Some parameters for the purification of NV virus-like particles (VLPs such as ease of production and yield were studied for future development of vaccines and diagnostic tools. In this study, VLPs were produced by the expression of the VP1 and VP2 gene cassette of the Brazilian NV isolate, and two purification methods were compared: cesium chloride (CsCl gradient centrifugation and ion-exchange chromatography (IEC. IEC produced more and purer VLPs of NV compared to CsCl gradient centrifugation.

  2. Exposure to Airborne Noroviruses and Other Bioaerosol Components at a Wastewater Treatment Plant in Denmark

    DEFF Research Database (Denmark)

    Uhrbrand, Katrine; Schultz, Anna Charlotte; Madsen, Anne Mette

    2011-01-01

    . The objective of the study was therefore to examine the exposure of the workers to aerosolised microorganisms. Sampling of inhalable endotoxin, bacteria, moulds and viruses was performed on one occasion using personal samplers. Noroviruses (NoVs) and endotoxin were detected at concentrations that could pose...... an occupational health risk and possibly contribute to the increased frequency of gastrointestinal illness among the workers and should therefore be investigated further. In addition, positive correlations between exposure to endotoxin, bacteria, moulds and NoVs were found and indicate that the exposure...

  3. Detection, quantification and genotyping of noroviruses in oysters implicated in disease outbreaks

    DEFF Research Database (Denmark)

    Haefeli, Deborah; Gantenbein-Demarchi, Corinne; Böttiger, Blenda

    2012-01-01

    Noroviruses (NoVs) are a major cause of foodborne outbreaks of acute gastroenteritis in humans. Transmission of NoV is commonly linked to the consumption of oysters as they accumulate viruses through filter feeding in faecal-contaminated water. The NoV genogroups (G)I, GII and GIV infect humans....... While GI and GII have often been verified as causative agents of oyster-transmitted illness, GIV is rarely detected and has so far not been confirmed in outbreaks related to oysters. The aim of this study was to determine whether NoVs from oysters implicated in a disease outbreak were linked to the GI...

  4. Sewage surveillance reveals the presence of canine GVII norovirus and canine astrovirus in Uruguay.

    Science.gov (United States)

    Lizasoain, A; Tort, L F L; García, M; Gómez, M M; Leite, J P G; Miagostovich, M P; Cristina, J; Berois, M; Colina, R; Victoria, Matías

    2015-11-01

    Canine norovirus (NoV) and astrovirus (AstV) were studied in 20 domestic sewage samples collected in two cities in Uruguay. Four samples were characterized as canine AstV after phylogenetic analysis clustering with strains detected in Italy and Brazil in 2008 and 2012, respectively. One sample was characterized as canine NoV and clustered with a strain detected in Hong Kong and recently classified as GVII. This study shows the occurrence of a canine NoV GVII strain for the first time in the American continent and also warns about possible zoonotic infection, since canine strains were detected in domestic sewage.

  5. Experiencias en la vigilancia epidemiológica de agentes patógenos transmitidos por alimentos a través de electroforesis en campo pulsado (PFGE) en el Perú Experiences in the epidemiological surveillance of foodborne pathogens by pulsed field gel electrophoresis (PFGE) in Peru

    OpenAIRE

    María Luz Zamudio; Ana Meza; Henri Bailón; Jaime Martinez-Urtaza; Josefina Campos

    2011-01-01

    Las enfermedades transmitidas por alimentos (ETA) y otras enfermedades entéricas infecciosas ocurren a menudo como brotes y son causa de morbilidad y mortalidad en todo el mundo. En el Perú, son un importante problema de salud pública y son causados por una gran variedad de agentes infecciosos. Para la investigación epidemiológica se utiliza una variedad de métodos de tipificación. Una de las herramientas más importantes en la subtipificación molecular de patógenos bacterianos es la técnica d...

  6. Outbreak of norovirus infection in a nursing home for the elderly in Malta, November-December 2008.

    Science.gov (United States)

    Grima, A; Gatt, A; Zahra, G; Gambin, A

    2009-01-29

    In norovirus outbreak in a nursing home in Malta in November and December 2008, 44 people were affected. 35 of 91 residents and nine of 44 employees were symptomatic. The overall attack rate among residents was 38.5% [corrected]. The outbreak lasted 17 days and the symptoms were mild.

  7. Complete Genome Sequence of a Recombinant GII.P16-GII.4 Norovirus Detected in Kawasaki City, Japan, in 2016

    Science.gov (United States)

    Matsushima, Yuki; Shimizu, Tomomi; Ishikawa, Mariko; Komane, Ayako; Okabe, Nobuhiko; Ryo, Akihide; Kimura, Hirokazu; Katayama, Kazuhiko

    2016-01-01

    A recombinant norovirus, GII.P16-GII.4_Sydney2012, was first detected from nine patients with gastroenteritis in Kawasaki City, Japan, in 2016. The viral genome showed nucleotide sequence identities of 95.1% and 97.2% to the closest strains in the regions of 5′ terminus to ORF1 and ORF2 to 3′ terminus, respectively.

  8. Development of one-step Loop-Mediated Isothermal Amplification (LAMP) for the detection of norovirus in oysters

    Science.gov (United States)

    The aim of this study was to develop a simple and rapid technique for detecting human norovirus (NoV). The loop-mediated isothermal amplification (LAMP) technique was evaluated and found to be sensitive, highly specific, and useful for routine oyster testing. Reverse transcription-LAMP (RT-LAMP) pri...

  9. Antiviral Activity of Gold/Copper Sulfide Core/Shell Nanoparticles against Human Norovirus Virus-Like Particles.

    Directory of Open Access Journals (Sweden)

    Jessica Jenkins Broglie

    Full Text Available Human norovirus is a leading cause of acute gastroenteritis worldwide in a plethora of residential and commercial settings, including restaurants, schools, and hospitals. Methods for easily detecting the virus and for treating and preventing infection are critical to stopping norovirus outbreaks, and inactivation via nanoparticles (NPs is a more universal and attractive alternative to other physical and chemical approaches. Using norovirus GI.1 (Norwalk virus-like particles (VLPs as a model viral system, this study characterized the antiviral activity of Au/CuS core/shell nanoparticles (NPs against GI.1 VLPs for the rapid inactivation of HuNoV. Inactivation of VLPs (GI.1 by Au/CuS NPs evaluated using an absorbance-based ELISA indicated that treatment with 0.083 μM NPs for 10 min inactivated ~50% VLPs in a 0.37 μg/ml VLP solution and 0.83 μM NPs for 10 min completely inactivated the VLPs. Increasing nanoparticle concentration and/or VLP-NP contact time significantly increased the virucidal efficacy of Au/CuS NPs. Changes to the VLP particle morphology, size, and capsid protein were characterized using dynamic light scattering, transmission electron microscopy, and Western blot analysis. The strategy reported here provides the first reported proof-of-concept Au/CuS NPs-based virucide for rapidly inactivating human norovirus.

  10. Multicenter evaluation of the revised RIDA® QUICK test (N1402) for rapid detection of norovirus in a diagnostic laboratory setting.

    Science.gov (United States)

    Jonckheere, Stijn; Botteldoorn, Nadine; Vandecandelaere, Patricia; Frans, Johan; Laffut, Wim; Coppens, Guy; Vankeerberghen, Anne; De Beenhouwer, Hans

    2017-02-12

    The updated RIDA® QUICK (N1402) immunochromatographic assay (R-Biopharm) for detection of norovirus was evaluated during a prospective, multicenter study using 771 stool samples from patients with gastroenteritis. Compared to real-time reverse transcriptase polymerase chain reaction (RT-rtPCR) as gold standard, the RIDA® QUICK had an overall sensitivity of 72.8% (91/125) and a specificity of 99.5% (640/643). Genotype analysis of the polymerase (ORF1) and capsid (ORF2) region of the genome indicated that the RIDA® QUICK assay could detect a broad range of genotypes including new variants (15 of 125 positive samples) which were detected by an in-house SYBR®Green RT-rtPCR, but not by the RIDA® GENE PCR PG1415 (R-Biopharm) and mostly not by the RIDA® GENE PCR PG1405 and the Xpert® Norovirus assay (Cepheid). The RIDA® QUICK can be used to reliably confirm norovirus in stool samples, but a negative result does not definitively exclude the presence of norovirus.

  11. Comparative survival of Escherichia coli O157:H7, Salmonella Typhimurium, and Murine Norovirus on spinach plants

    Science.gov (United States)

    Introduction: Outbreaks resulting from the consumption of leafy greens contaminated with E. coli O157:H7, Salmonella spp., and norovirus have occurred. It is unclear how the stress response factor rpoS in E. coli O157:H7 and Salmonella spp. affects their survival on spinach. Purpose: A comparison ...

  12. Detection of noroviruses in foods: a study on virus extraction procedures in foods implicated in outbreaks of human gastroenteritis.

    NARCIS (Netherlands)

    Rutjes, Saskia A; Lodder-Verschoor, Froukje; Poel, Wim H M van der; Duynhoven, Yvonne T H P van; Roda Husman, Ana Maria de

    2006-01-01

    Disease outbreaks in which foods are epidemiologically implicated as the common source are frequently reported. Noroviruses and enteric hepatitis A viruses are among the most prevalent causative agents of foodborne diseases. However, the detection of these viruses in foods other than shellfish is of

  13. Diversity of murine norovirus in wild-rodent populations: species-specific associations suggest an ancient divergence.

    Science.gov (United States)

    Smith, Donald B; McFadden, Nora; Blundell, Richard J; Meredith, Anna; Simmonds, Peter

    2012-02-01

    A survey of wild-rodent populations has revealed that murine norovirus (MNV) is present and diverse in wild-house mice Mus musculus. This virus is genetically similar to MNV infecting show mice and previously described variants circulating in laboratory mice. The detection of MNV in wild-mouse populations suggests that MNV infection of laboratory mice and show mice (from which laboratory mice are derived) derives from contact with or their origins from wild-mouse progenitors. The survey additionally identified frequent infection of wood mice (Apodemus sylvaticus) with genetically divergent variants of MNV. These viruses are distinct from previously described MNV variants, differing by 22-23 % over the complete genome sequence compared with a maximum of 13 % between M. musculus-derived strains. Comparison with other noroviruses reveals that the Apodemus MNV groups with MNV in genogroup V and shares the same overall genome organization, predicted lengths of proteins encoded by ORFs 1-3 and the existence of a conserved alternative reading frame in VP1 encoding a homologue of the MNV ORF4. Different Apodemus MNV isolates were as variable as MNV isolates and showed evidence for inter-isolate recombination. Our observation of species-specific associations of MNV variants in wild populations suggests that murine noroviruses have an ancient origin, a feature that they may share with other norovirus genogroups.

  14. Sequence Analysis of the Capsid Gene during a Genotype II.4 Dominated Norovirus Season in One University Hospital

    DEFF Research Database (Denmark)

    Holzknecht, Barbara Juliane; Franck, Kristina Træholt; Nielsen, Rikke Thoft;

    2015-01-01

    Norovirus (NoV) is a leading cause of gastroenteritis and genotype II.4 (GII.4) is responsible for the majority of nosocomial NoV infections. Our objective was to examine whether sequencing of the capsid gene might be a useful tool for the hospital outbreak investigation to define possible...

  15. Brote de gripe A H1N1 en la base española de Camp "Arena" (Herat, Afganistán durante julio y agosto de 2009. Parte II: Medidas clínicas y preventivas Outbreak of Influenza A H1N1 in Spanish base Camp "Arena" (Herat, Afghanistan during july and august 2009. Part II: Clinical and preventive measures

    Directory of Open Access Journals (Sweden)

    F. Maimir Jané

    2011-03-01

    Full Text Available La Base de Camp "Arena" en Herat (Afganistán presentó durante los pasados meses de julio y agosto de 2009 un total de 121 casos de gripe A H1N1, 22 de ellos casos confirmados y el resto diagnosticados por "vínculo epidemiológico". Presentamos en el presente artículo las medidas clínicas y preventivas que fueron tomadas en la Base, en el intento de controlar el número de casos y asegurar la operatividad de la Base y el cumplimiento de la misión encomendada al contingente. Se revisan las características de la Base, las medidas tomadas con los pacientes, las medidas tomadas con los contactos, reflejando las dos distintas organizaciones que se realizaron al inicio del brote y posteriormente, las medidas generales tomadas en la Base y las medidas especiales características por tratarse de una unidad militar en una Zona de Operaciones. Finalmente realizamos una reflexión sobre algunas de las medidas tomadas.The Base Camp "Arena" in Herat (Afghanistan presented during the months of July and August 2009 a total of 121 cases of Flu A H1N1 (22 confirmed cases and the rest were diagnosed by epidemiological link. We present in this article the clinical and preventive measures taken at the base in an attempt to control the number of cases and ensure the operability of the base and fulfilling the mission entrusted to the quota. We review the characteristics of the Base, measures taken with patients, the measures taken with the contacts reflecting the two different organizations taken initially and during the second period that conducted at the outset of the outbreak, the general measures taken on the base and special measures because it features of a military unit in an area of operations. Finally we perform a reflection of some taken actions.

  16. Bovine Norovirus: Carbohydrate Ligand, Environmental Contamination, and Potential Cross-Species Transmission via Oysters ▿ †

    Science.gov (United States)

    Zakhour, Maha; Maalouf, Haifa; Di Bartolo, Ilaria; Haugarreau, Larissa; Le Guyader, Françoise S.; Ruvoën-Clouet, Nathalie; Le Saux, Jean-Claude; Ruggeri, Franco Maria; Pommepuy, Monique; Le Pendu, Jacques

    2010-01-01

    Noroviruses (NoV) are major agents of acute gastroenteritis in humans and the primary pathogens of shellfish-related outbreaks. Previous studies showed that some human strains bind to oyster tissues through carbohydrate ligands that are similar to their human receptors. Thus, based on presentation of shared norovirus carbohydrate ligands, oysters could selectively concentrate animal strains with increased ability to overcome species barriers. In comparison with human GI and GII strains, bovine GIII NoV strains, although frequently detected in bovine feces and waters of two estuaries of Brittany, were seldom detected in oysters grown in these estuaries. Characterization of the carbohydrate ligand from a new GIII strain indicated recognition of the alpha-galactosidase (α-Gal) epitope not expressed by humans, similar to the GIII.2 Newbury2 strain. This ligand was not detectable on oyster tissues, suggesting that oysters may not be able to accumulate substantial amounts of GIII strains due to the lack of shared carbohydrate ligand and that they should be unable to contribute to select GIII strains with an increased ability to recognize humans. PMID:20709837

  17. Murine norovirus (MNV-1) exposure in vitro to the purine nucleoside analog Ribavirin increases quasispecies diversity.

    Science.gov (United States)

    Julian, Timothy R; Baugher, Joseph D; Rippinger, Christine M; Pinekenstein, Rebecca; Kolawole, Abimbola O; Mehoke, Thomas S; Wobus, Christiane E; Feldman, Andrew B; Pineda, Fernando J; Schwab, Kellogg J

    2016-01-04

    Ribavirin is a pharmaceutical antiviral used for the treatment of RNA virus infections including norovirus, hepatitis C virus, hepatitis E virus, Lassa virus, respiratory syncytial virus, and rhinovirus. Despite the drug's history and documented efficacy, the antiviral mechanism of Ribavirin remains unclear. Mechanisms proposed include depletion of the intracellular GTP pool, immunomodulatory effects, induction of error catastrophe, inhibition of viral polymerase activity, and/or inhibition of viral capping. In the present study, we leveraged deep sequencing data to demonstrate that Ribavirin increases murine norovirus (MNV-1) viral diversity. By serial passaging MNV-1 in RAW 264.7 cells for twenty generations in the presence of Ribavirin, we demonstrated statistically significant increases in both the number of unique haplotypes and the average pairwise difference (APD). Based on statistically significant differences in the probability of nucleotide mutations based on Roche 454 sequencing, we also demonstrated that single nucleotide substitutions are increased in the presence of Ribavirin. Finally, we demonstrated Ribavirin's impact on statistically significantly reducing the relative proportion of the dominant sequence within the quasispecies.

  18. Norovirus epidemiology in community and health care settings and association with patient age, Denmark.

    Science.gov (United States)

    Franck, Kristina T; Fonager, Jannik; Ersbøll, Annette K; Böttiger, Blenda

    2014-07-01

    Norovirus (NoV) is a major cause of gastroenteritis. NoV genotype II.4 (GII.4) is the predominant genotype in health care settings but the reason for this finding is unknown. Stool samples containing isolates with a known NoV genotype from 2,109 patients in Denmark (patients consulting a general practitioner or outpatient clinic, inpatients, and patients from foodborne outbreaks) were used to determine genotype distribution in relation to age and setting. NoV GII.4 was more prevalent among inpatients than among patients in community settings or those who became infected during foodborne outbreaks. In community and health care settings, we found an association between infection with GII.4 and increasing age. Norovirus GII.4 predominated in patients ≥ 60 years of age and in health care settings. A larger proportion of children than adults were infected with NoV GII.3 or GII.P21. Susceptibility to NoV infection might depend on patient age and infecting NoV genotype. Cohort studies are warranted to test this hypothesis.

  19. Inactivation of Human Norovirus and Its Surrogates on Alfalfa Seeds by Aqueous Ozone.

    Science.gov (United States)

    Wang, Qing; Markland, Sarah; Kniel, Kalmia E

    2015-08-01

    Alfalfa sprouts have been associated with numerous foodborne outbreaks. Previous studies investigated the effectiveness of aqueous ozone on bacterially contaminated seeds, yet little is known about the response of human norovirus (huNoV). This study assessed aqueous ozone for the disinfection of alfalfa seeds contaminated with huNoV and its surrogates. The inactivation of viruses without a food matrix was also investigated. Alfalfa seeds were inoculated with huNoV genogroup II, Tulane virus (TV), and murine norovirus (MNV); viruses alone or inoculated on seeds were treated in deionized water containing 6.25 ppm of aqueous ozone with agitation at 22°C for 0.5, 1, 5, 15, or 30 min. The data showed that aqueous ozone resulted in reductions of MNV and TV infectivity from 1.66 ± 1.11 to 5.60 ± 1.11 log PFU/g seeds; for all treatment times, significantly higher reductions were observed for MNV (P water was similar to that of huNoV, whereas MNV had significantly greater reductions in genomic copies (P ozone-treated viruses alone, with significantly higher levels of inactivation (P ozone indicates that ozone may be a plausible substitute for chlorine as an alternative treatment for seeds. The behavior of TV was similar to that of huNoV, which makes it a promising surrogate for these types of scenarios.

  20. High-Resolution X-Ray Structure and Functional Analysis of the Murine Norovirus 1 Capsid Protein Protruding Domain

    Energy Technology Data Exchange (ETDEWEB)

    Taube, Stefan; Rubin, John R.; Katpally, Umesh; Smith, Thomas J.; Kendall, Ann; Stuckey, Jeanne A.; Wobus, Christiane E. (Michigan); (Danforth)

    2010-07-23

    Murine noroviruses (MNV) are closely related to the human noroviruses (HuNoV), which cause the majority of nonbacterial gastroenteritis. Unlike HuNoV, MNV grow in culture and in a small-animal model that represents a tractable model to study norovirus biology. To begin a detailed investigation of molecular events that occur during norovirus binding to cells, the crystallographic structure of the murine norovirus 1 (MNV-1) capsid protein protruding (P) domain has been determined. Crystallization of the bacterially expressed protein yielded two different crystal forms (Protein Data Bank identifiers [PDB ID], 3LQ6 and 3LQE). Comparison of the structures indicated a large degree of structural mobility in loops on the surface of the P2 subdomain. Specifically, the A{prime}-B{prime} and E{prime}-F{prime} loops were found in open and closed conformations. These regions of high mobility include the known escape mutation site for the neutralizing antibody A6.2 and an attenuation mutation site, which arose after serial passaging in culture and led to a loss in lethality in STAT1{sup -/-} mice, respectively. Modeling of a Fab fragment and crystal structures of the P dimer into the cryoelectron microscopy three-dimensional (3D) image reconstruction of the A6.2/MNV-1 complex indicated that the closed conformation is most likely bound to the Fab fragment and that the antibody contact is localized to the A{prime}-B{prime} and E{prime}-F{prime} loops. Therefore, we hypothesize that these loop regions and the flexibility of the P domains play important roles during MNV-1 binding to the cell surface.

  1. Absolute quantification of norovirus capsid protein in food, water, and soil using synthetic peptides with electrospray and MALDI mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Erica M. [Center for Environmental Security and Security Defense Systems Initiative, The Biodesign Institute, Arizona State University, 781 E. Terrace Mall, Tempe, AZ 85287-5904 (United States); Colquhoun, David R.; Schwab, Kellogg J. [Department of Environmental Health Sciences, The Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe St., Baltimore, MD 21205 (United States); Halden, Rolf U., E-mail: halden@asu.edu [Center for Environmental Security and Security Defense Systems Initiative, The Biodesign Institute, Arizona State University, 781 E. Terrace Mall, Tempe, AZ 85287-5904 (United States); Department of Environmental Health Sciences, The Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe St., Baltimore, MD 21205 (United States)

    2015-04-09

    Highlights: • Mass spectrometry-based methods for norovirus quantification are developed. • Absolute quantification is achieved using internal heavy isotope-labeled standards. • A single labeled peptide serves in two distinct detection strategies. • These methods are validated for food, water, and soil analysis. • MS-based detection limits are lowered by two orders of magnitude. - Abstract: Norovirus infections are one of the most prominent public health problems of microbial origin in the U.S. and other industrialized countries. Surveillance is necessary to prevent secondary infection, confirm successful cleanup after outbreaks, and track the causative agent. Quantitative mass spectrometry, based on absolute quantitation with stable-isotope labeled peptides, is a promising tool for norovirus monitoring because of its speed, sensitivity, and robustness in the face of environmental inhibitors. In the current study, we present two new methods for the detection of the norovirus genogroup I capsid protein using electrospray and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The peptide TLDPIEVPLEDVR was used to quantify norovirus-like particles down to 500 attomoles with electrospray and 100 attomoles with MALDI. With MALDI, we also demonstrate a detection limit of 1 femtomole and a quantitative dynamic range of 5 orders of magnitude in the presence of an environmental matrix effect. Due to the rapid processing time and applicability to a wide range of environmental sample types (bacterial lysate, produce, milk, soil, and groundwater), mass spectrometry-based absolute quantitation has a strong potential for use in public health and environmental sciences.

  2. Comparison of nucleic acid extraction and reverse transcription-qPCR approaches for detection of GI and GII noroviruses in drinking water

    Science.gov (United States)

    Noroviruses (NoVs) are responsible for a number of waterborne and foodborne gastroenteritis cases each year. They are frequently associated with human sewage, and thus a potential link between wastewater discharge and contamination of source waters exists. Subsequently, contami...

  3. Crystal Structures of GII.10 and GII.12 Norovirus Protruding Domains in Complex with Histo-Blood Group Antigens Reveal Details for a Potential Site of Vulnerability

    Energy Technology Data Exchange (ETDEWEB)

    Hansman, Grant S.; Biertümpfel, Christian; Georgiev, Ivelin; McLellan, Jason S.; Chen, Lei; Zhou, Tongqing; Katayama, Kazuhiko; Kwong, Peter D. (NIH); (NIID-Japan)

    2011-10-10

    Noroviruses are the dominant cause of outbreaks of gastroenteritis worldwide, and interactions with human histo-blood group antigens (HBGAs) are thought to play a critical role in their entry mechanism. Structures of noroviruses from genogroups GI and GII in complex with HBGAs, however, reveal different modes of interaction. To gain insight into norovirus recognition of HBGAs, we determined crystal structures of norovirus protruding domains from two rarely detected GII genotypes, GII.10 and GII.12, alone and in complex with a panel of HBGAs, and analyzed structure-function implications related to conservation of the HBGA binding pocket. The GII.10- and GII.12-apo structures as well as the previously solved GII.4-apo structure resembled each other more closely than the GI.1-derived structure, and all three GII structures showed similar modes of HBGA recognition. The primary GII norovirus-HBGA interaction involved six hydrogen bonds between a terminal {alpha}fucose1-2 of the HBGAs and a dimeric capsid interface, which was composed of elements from two protruding subdomains. Norovirus interactions with other saccharide units of the HBGAs were variable and involved fewer hydrogen bonds. Sequence analysis revealed a site of GII norovirus sequence conservation to reside under the critical {alpha}fucose1-2 and to be one of the few patches of conserved residues on the outer virion-capsid surface. The site was smaller than that involved in full HBGA recognition, a consequence of variable recognition of peripheral saccharides. Despite this evasion tactic, the HBGA site of viral vulnerability may provide a viable target for small molecule- and antibody-mediated neutralization of GII norovirus.

  4. Use of sequence analysis of the P2 domain for characterization of norovirus strains causing a large multistate outbreak of norovirus gastroenteritis in Germany 2012.

    Science.gov (United States)

    Höhne, Marina; Niendorf, Sandra; Mas Marques, Andreas; Bock, C-Thomas

    2015-10-01

    Human norovirus is the main cause of non-bacterial gastroenteritis worldwide. It is transmitted from person to person, by fecally contaminated food or water or through virus containing aerosols originating during vomiting of infected persons. In September and October 2012, the largest foodborne norovirus outbreak in Germany so far spread over 5 Federal States (Berlin, Brandenburg, Saxony, Saxony-Anhalt, and Thuringia) affecting nearly 11,000 people mainly in schools and child care facilities. Epidemiological and trace-back investigations supported the assumption that a batch of frozen strawberries imported from China was the likely source of the outbreak. Sequence analysis of the capsid region encoding the P2 domain was used successfully for identification of transmission routes and epidemiologic relationship but was hampered by a lack of universal primers for all known genotypes so far. In the present study, a molecular approach was designed to track outbreak-related samples from the affected states of the large foodborne outbreak in Germany. Therefore, sequence analysis within the highly variable P2 domain of the capsid gene using newly developed universal P2 primers for genogroup I and genogroup II strains in combination with sequencing of the polymerase gene (region A) and the orf1/orf2 junction (region c) was used. The sequence analysis of 138 norovirus positive stool samples suspected to be outbreak-related revealed a considerable genomic diversity. At least 3 strains of genogroup I (I.3, I.4, and I.9) and 5 strains of genogroup II (II.6, II.7, II. 8, and recombinants II.P7_II.6, and II.P16_II.13) as well as 19 samples containing mixtures of these strains were detected. Six samples were considered as not linked to the outbreak. The most prevalent genotype was GI.4 (48/132; 36%). Genotype I.9 and the recombinant strain II.P16_II.13 were detected for the first time in Germany. Notably, the genotype II.P16_II.13 could also be determined in one of the samples of

  5. Enfermedad por el virus Ébola medidas de bioseguridad

    Directory of Open Access Journals (Sweden)

    Kattia Bucknor Johnson

    2015-12-01

    Full Text Available El virus Ébola representa el patógeno prototipo de fiebre hemorrágica viral, causando una enfermedad severa de alta tasa de mortalidad. Esta alta mortalidad, combinada con la ausencia de vacunación y de un tratamiento específico, hace que el virus Ébola sea un patógeno importante para la salud pública. La fiebre hemorrágica de Ébola se cree es una zoonosis con persistencia del virus en especies de reservorios encontrados en áreas endémicas. A pesar de todos los esfuerzos realizados en cada brote para identificar los reservorios naturales no se conocen los huéspedes potenciales ni los artrópodos vectores. El manejo de los casos está basado en el aislamiento de los pacientes y en el uso de barreras de aislamiento, tales como ropa e implementos de protección como respiradores. Debido a su rápida propagación la OMS declaró que la enfermedad por el virus Ébola representa una emergencia de salud pública más allá de las fronteras y exhortó a la comunidad internacional a tomar las acciones necesarias para detener la epidemia.

  6. Functional receptor molecules CD300lf and CD300ld within the CD300 family enable murine noroviruses to infect cells

    Science.gov (United States)

    Haga, Kei; Fujimoto, Akira; Takai-Todaka, Reiko; Miki, Motohiro; Doan, Yen Hai; Murakami, Kosuke; Yokoyama, Masaru; Murata, Kazuyoshi; Nakanishi, Akira; Katayama, Kazuhiko

    2016-01-01

    Norovirus is the leading cause of acute gastroenteritis worldwide. Since the discovery of human norovirus (HuNoV), an efficient and reproducible norovirus replication system has not been established in cultured cells. Although limited amounts of virus particles can be produced when the HuNoV genome is directly transfected into cells, the HuNoV cycle of infection has not been successfully reproduced in any currently available cell-culture system. Those results imply that the identification of a functional cell-surface receptor for norovirus might be the key to establishing a norovirus culture system. Using a genome-wide CRISPR/Cas9 guide RNA library, we identified murine CD300lf and CD300ld as functional receptors for murine norovirus (MNV). The treatment of susceptible cells with polyclonal antibody against CD300lf significantly reduced the production of viral progeny. Additionally, ectopic CD300lf expression in nonsusceptible cell lines derived from other animal species enabled MNV infection and progeny production, suggesting that CD300lf has potential for dictating MNV host tropism. Furthermore, CD300ld, which has an amino acid sequence in the N-terminal region of its extracellular domain that is highly homologous to that of CD300lf, also functions as a receptor for MNV. Our results indicate that direct interaction of MNV with two cell-surface molecules, CD300lf and CD300ld, dictates permissive noroviral infection. PMID:27681626

  7. Early Detection of Epidemic GII-4 Norovirus Strains in UK and Malawi: Role of Surveillance of Sporadic Acute Gastroenteritis in Anticipating Global Epidemics.

    Directory of Open Access Journals (Sweden)

    David J Allen

    Full Text Available Noroviruses are endemic in the human population, and are recognised as a leading cause of acute gastroenteritis worldwide. Although they are a highly diverse group of viruses, genogroup-II genotype-4 (GII-4 noroviruses are the most frequently identified strains worldwide. The predominance of GII-4 norovirus strains is driven by the periodic emergence of antigenic variants capable of evading herd protection. The global molecular epidemiology of emerging GII-4 strains is largely based on data from outbreak surveillance programmes, but the epidemiology of GII-4 strains among sporadic or community cases is far less well studied. To understand the distribution of GII-4 norovirus strains associated with gastroenteritis in the wider population, we characterised the GII-4 norovirus strains detected during studies of sporadic cases of infectious gastroenteritis collected in the UK and Malawi between 1993 and 2009. Our data shows that GII-4 norovirus strains that have emerged as strains of global epidemic importance have circulated in the community up to 18 years before their recognition as pandemic strains associated with increases in outbreaks. These data may suggest that more comprehensive surveillance programmes that incorporate strains associated with sporadic cases may provide a way for early detection of emerging strains with pandemic potential. This may be of particular relevance as vaccines become available.

  8. Early Detection of Epidemic GII-4 Norovirus Strains in UK and Malawi: Role of Surveillance of Sporadic Acute Gastroenteritis in Anticipating Global Epidemics.

    Science.gov (United States)

    Allen, David J; Trainor, Eamonn; Callaghan, Anna; O'Brien, Sarah J; Cunliffe, Nigel A; Iturriza-Gómara, Miren

    2016-01-01

    Noroviruses are endemic in the human population, and are recognised as a leading cause of acute gastroenteritis worldwide. Although they are a highly diverse group of viruses, genogroup-II genotype-4 (GII-4) noroviruses are the most frequently identified strains worldwide. The predominance of GII-4 norovirus strains is driven by the periodic emergence of antigenic variants capable of evading herd protection. The global molecular epidemiology of emerging GII-4 strains is largely based on data from outbreak surveillance programmes, but the epidemiology of GII-4 strains among sporadic or community cases is far less well studied. To understand the distribution of GII-4 norovirus strains associated with gastroenteritis in the wider population, we characterised the GII-4 norovirus strains detected during studies of sporadic cases of infectious gastroenteritis collected in the UK and Malawi between 1993 and 2009. Our data shows that GII-4 norovirus strains that have emerged as strains of global epidemic importance have circulated in the community up to 18 years before their recognition as pandemic strains associated with increases in outbreaks. These data may suggest that more comprehensive surveillance programmes that incorporate strains associated with sporadic cases may provide a way for early detection of emerging strains with pandemic potential. This may be of particular relevance as vaccines become available.

  9. Intoxicación alimentaria por Clostridium perfringens en el Centro Penitenciario de Atención Institucional de San José: estudio de cohorte retrospectivo

    Directory of Open Access Journals (Sweden)

    Roy Wong-Mc Clure

    2004-06-01

    Full Text Available Las enfermedades transmitidas por los alimentos se presentan anualmente en Costa Rica y por lo general se estudian hasta identificar el agente etiológico, pero no hasta determinar su fuente de contaminación. No se ha documentado la importancia de fortalecer la inocuidad de alimentos, lo cual produce eventos que comprometen la salud pública cada año, por lo que fue importante estudiar el presente brote. En este estudio se analiza el brote diarreico de un centro penitenciario de San José, en 2003, procurando determinar el probable alimento contaminado. Materiales y métodos: El presente estudio corresponde a una cohorte retrospectiva que identifica exposición a los alimentos preparados dentro del Centro, en las 72 horas previas al pico epidémico. La descripción de la cohorte y el cálculo del (RR se realizó posteriormente para determinar la posible\tasociación causal. Las muestras de heces fueron procesadas en el laboratorio de referencia del INCIENSA. Resultados: La totalidad de los individuos pertenecían al sexo masculino, todos privados de libertad, con un promedio de edad de 31.1años (IC95%=28.9-33.4. La sintomatología más frecuente fue la diarrea (92.3% Y dolor abdominal tipo cólico (84.6%. El resultado de laboratorio aisló como agente etiológico el Clostridium perfringens enterotoxigénico (CPE. Al analizar los alimentos suministrados, pico epidémico y período de incubación, se tiene que el salchichón (RR=1.1;IC95%0.5-2.7 y la preparación con carne molida (RR=2.1,IC95%:0.6-7.4 mostraron ser los únicos alimentos capaces de transmitir el CPE. Discusión: El brote del Centro evidencia que la sintomatología descrita corresponde con lo documentado para la intoxicación por CPE y que, tomando en cuenta las condiciones necesarias para la transmisión, solo el salchichón y la preparación con carne molida cuentan con esta plausibilidad biológica. Al considerar el periodo de incubación, los valores de riesgo relativo

  10. Characterization of novel intragenotype recombination events among norovirus pandemic GII.4 variants.

    Science.gov (United States)

    Siqueira, Jones Anderson Monteiro; Bandeira, Renato da Silva; Justino, Maria Cleonice Aguiar; Linhares, Alexandre da Costa; Gabbay, Yvone Benchimol

    2016-10-01

    Recently, there has been an increase in the number of children hospitalized due to norovirus infection in Brazil. This is due both to the occurrence of more severe norovirus-related gastroenteritis cases after the introduction of the rotavirus vaccine and an increase in the tools for the detection of the disease. This pathogen is transmitted by the fecal-oral route, and the illness is characterized by diarrhea, vomiting, nausea and abdominal cramps. The genome of the virus is organized into three open reading frames showing strong mutation rates. Additionally, homologous recombination events, which can increase the virulence of the virus and lead to genotyping mistakes in molecular epidemiological studies, frequently occur. The purpose of this study was to describe two recombination events among different GII.4 variants that infected children who were hospitalized for severe acute gastroenteritis during distinct periods of time in Belém, Brazil. The recombination among the variants US95_96/Kaiso_2003 and Den Haag_2006b/Yerseke_2006a were observed in May 2003 and February 2009, respectively. In both cases, the association between the dominant variant at that point in time and another that was circulating at a low frequency in the population of Belém was demonstrated. Interestingly, the position of the breakpoint of the recombination event in the genome was the polymerase gene and was located at the nucleotide positions 4.834 and 5.002, which is an unusual location for the occurrence of recombination as other studies have previously reported the junction region as a breakpoint. In this study, both recombinant variant strains were related to severe cases of diarrhea that lead to hospitalization, demonstrating the viral evolution of GII.4 in response to selective pressures, which ultimately lead to the emergence of novel viral types in the pediatric population. The cases discussed here reinforce the need for continuous norovirus surveillance. To our knowledge, these

  11. A Membrane-Based Electro-Separation Method (MBES for Sample Clean-Up and Norovirus Concentration.

    Directory of Open Access Journals (Sweden)

    Wei Kang

    Full Text Available Noroviruses are the leading cause of acute gastroenteritis and foodborne illnesses in the United States. Enhanced methods for detecting noroviruses in food matrices are needed as current methods are complex, labor intensive and insensitive, often resulting in inhibition of downstream molecular detection and inefficient recovery. Membrane-based electro-separation (MBES is a technique to exchange charged particles through a size-specific dialysis membrane from one solution to another using electric current as the driving force. Norovirus has a net negative surface charge in a neutrally buffered environment, so when placed in an electric field, it moves towards the anode. It can then be separated from the cathodic compartment where the sample is placed and then collected in the anodic compartment for downstream detection. In this study, a MBES-based system was designed, developed and evaluated for concentrating and recovering murine norovirus (MNV-1 from phosphate buffer. As high as 30.8% MNV-1 migrated from the 3.5 ml sample chamber to the 1.5 ml collection chamber across a 1 μm separation membrane when 20 V was applied for 30 min using 20 mM sodium phosphate with 0.01% SDS (pH 7.5 as the electrolyte. In optimization of the method, weak applied voltage (20 V, moderate duration (30 min, and low ionic strength electrolytes with SDS addition were needed to increase virus movement efficacy. The electric field strength of the system was the key factor to enhance virus movement, which could only be improved by shortening the electrodes distance, instead of increasing system applied voltage because of virus stability. This study successfully demonstrated the norovirus mobility in an electric field and migration across a size-specific membrane barrier in sodium phosphate electrolyte. With further modification and validation in food matrixes, a novel, quick, and cost-effective sample clean-up technique might be developed to separate norovirus particles

  12. Brote de legionelosis en Murcia en julio de 2001. La óptica de sanidad ambiental Outbreak of Legionella disease in Murcia, at July 2001. The environmental health point of view

    Directory of Open Access Journals (Sweden)

    F. Sintas Lozano

    2002-06-01

    Full Text Available Se exponen las medidas de intervención adoptadas para el estudio y control del brote. Se encontraron 126 instalaciones con riesgo (45 de ellas de alto: 70 torres de refrigeración y similares, 35 fuentes ornamentales, 1 obra con movimiento de tierra y 20 sistemas con circuito cerrado aire-agua, que se distribuyeron por categorías de riesgo.De forma inmediata se clausuraron: las fuentes ornamentales, el baldeo de calles y riegos por aspersión de parques y la obra.Se realizaron un total de 486 inspecciones y 1040 toma de muestras, ordenando la limpieza y desinfección de torres de refrigeración y similares y su clausura en caso necesario. Posteriormente, se cambio de relleno en torres de refrigeración positivas a Lp.Del total de instalaciones investigadas (339, en 57 (16’9% se encontró un cultivo positivo a Lp. Distribución por tipo de instalación con cultivo positivo a Lp: en torres de refrigeración 23 (6’8%, en fuentes ornamentales 3 (7,32% y en agua sanitaria 31 (9’1%.Distribución por serogrupos: LpS1 (62’3%, serogrupos 2-14 (36’68%.LpS1Olda Olda (21’74% fue la mas abundante seguida de LpS1 Pontiac Filadelfia Lugano (18’84% frente a LpS1 Pontiac Filadelfia Glasgow (en 1 ocasión, 1’45%, esta ultima fue la aislada en las 18 muestras de enfermos.En 355 ocasiones se dispone de cultivo y PCR, encontrándose una sensibilidad de 30,8% (Intervalo de confianza al 95%, de 25,1 y una especificidad del 99,4±0,8. Hay que considerar la eventual influencia en los resultados aportada por la posible aparición de dos falsos negativos en el cultivo.Se encuentra un elevado porcentaje de muestras correspondientes a Legionella pneumophilla serogrupo 1, dentro de estas prevalecen las tipo Pontiac Philadelphia, y dentro de estas las tipo Lugano.La primera desinfección no erradicó la contaminación en su totalidad. Abundando en lo anterior, el hallazgo de un número considerable de torres de refrigeración positivas a Lp tras limpieza y

  13. Molecular epidemiology of rotavirus and norovirus in Ile-Ife, Nigeria: high prevalence of G12P[8] rotavirus strains and detection of a rare norovirus genotype.

    Science.gov (United States)

    Oluwatoyin Japhet, Margaret; Adeyemi Adesina, Olufisayo; Famurewa, Oladiran; Svensson, Lennart; Nordgren, Johan

    2012-09-01

    Rotavirus (RV) and norovirus (NoV) are considered the most common causes of viral gastroenteritis in children. In this study, the prevalence of RV and NoV infection in 55 children with diarrhea from the rural community Akinlalu in Southwestern Nigeria was investigated using real-time PCR assays. The RV and NoV strains were genotyped by PCR and/or sequencing. RV and NoV infections occurred with a prevalence of 34.5% and 25.5% respectively, with predominance in children 99%) indicating introduction in Nigeria from a single donor. Furthermore, a putative novel genotype within genogroup I NoV was detected, which till date has only been reported once in humans. To conclude, a high prevalence of the emerging G12P[8] RV strain was observed for the first time in Nigeria, as well as a putative novel NoV genotype in humans. These results provide new information which can be important for future vaccine evaluations and possible introduction in Nigeria.

  14. Incidence of Norovirus and Other Viral Pathogens That Cause Acute Gastroenteritis (AGE) among Kaiser Permanente Member Populations in the United States, 2012-2013.

    Science.gov (United States)

    Grytdal, Scott P; DeBess, Emilio; Lee, Lore E; Blythe, David; Ryan, Patricia; Biggs, Christianne; Cameron, Miriam; Schmidt, Mark; Parashar, Umesh D; Hall, Aron J

    2016-01-01

    Noroviruses and other viral pathogens are increasingly recognized as frequent causes of acute gastroenteritis (AGE). However, few laboratory-based data are available on the incidence of AGE caused by viral pathogens in the U.S. This study examined stool specimens submitted for routine clinical diagnostics from patients enrolled in Kaiser Permanente (KP) health plans in metro Portland, OR, and the Maryland, District of Columbia, and northern Virginia geographic areas to estimate the incidence of viral enteropathogens in these populations. Over a one-year study period, participating laboratories randomly selected stools submitted for routine clinical diagnostics for inclusion in the study along with accompanying demographic and clinical data. Selected stools were tested for norovirus, rotavirus, sapovirus, and astrovirus using standardized real-time RT-PCR protocols. Each KP site provided administrative data which were used in conjunction with previously published data on healthcare utilization to extrapolate pathogen detection rates into population-based incidence rates. A total of 1,099 specimens collected during August 2012 to September 2013 were included. Mean age of patients providing stool specimens was 46 years (range: 0-98 years). Noroviruses were the most common viral pathogen identified among patients with AGE (n = 63 specimens, 6% of specimens tested). In addition, 22 (2%) of specimens were positive for rotavirus; 19 (2%) were positive for sapovirus; and 7 (1%) were positive for astrovirus. Incidence of norovirus-associated outpatient visits was 5.6 per 1,000 person-years; incidence of norovirus disease in the community was estimated to be 69.5 per 1,000 person-years. Norovirus incidence was highest among children 65 years (outpatient incidence = 7.8 per 1,000 person-years; community incidence = 75.8 per 1,000 person-years). Outpatient incidence rates of rotavirus, sapovirus, and astrovirus were 2.0, 1.6, 0.6 per 1,000 person-years, respectively; community

  15. Incidence of Norovirus and Other Viral Pathogens That Cause Acute Gastroenteritis (AGE among Kaiser Permanente Member Populations in the United States, 2012-2013.

    Directory of Open Access Journals (Sweden)

    Scott P Grytdal

    Full Text Available Noroviruses and other viral pathogens are increasingly recognized as frequent causes of acute gastroenteritis (AGE. However, few laboratory-based data are available on the incidence of AGE caused by viral pathogens in the U.S. This study examined stool specimens submitted for routine clinical diagnostics from patients enrolled in Kaiser Permanente (KP health plans in metro Portland, OR, and the Maryland, District of Columbia, and northern Virginia geographic areas to estimate the incidence of viral enteropathogens in these populations. Over a one-year study period, participating laboratories randomly selected stools submitted for routine clinical diagnostics for inclusion in the study along with accompanying demographic and clinical data. Selected stools were tested for norovirus, rotavirus, sapovirus, and astrovirus using standardized real-time RT-PCR protocols. Each KP site provided administrative data which were used in conjunction with previously published data on healthcare utilization to extrapolate pathogen detection rates into population-based incidence rates. A total of 1,099 specimens collected during August 2012 to September 2013 were included. Mean age of patients providing stool specimens was 46 years (range: 0-98 years. Noroviruses were the most common viral pathogen identified among patients with AGE (n = 63 specimens, 6% of specimens tested. In addition, 22 (2% of specimens were positive for rotavirus; 19 (2% were positive for sapovirus; and 7 (1% were positive for astrovirus. Incidence of norovirus-associated outpatient visits was 5.6 per 1,000 person-years; incidence of norovirus disease in the community was estimated to be 69.5 per 1,000 person-years. Norovirus incidence was highest among children 65 years (outpatient incidence = 7.8 per 1,000 person-years; community incidence = 75.8 per 1,000 person-years. Outpatient incidence rates of rotavirus, sapovirus, and astrovirus were 2.0, 1.6, 0.6 per 1,000 person

  16. Norovirus Outbreak Investigation in Surmene District of Trabzon Province July 2010

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    Gamze Can

    2011-10-01

    Full Text Available Bu calismada, Temmuz 2010’da Trabzon Ilinin Surmene Ilcesinde meydana gelen norovirus salgininda yapilan incelemeleri sunmak amaclanmistir. Akut gastroenterit vakalari ilk olarak 09 Temmuz tarihinde ortaya cikmaya baslamis ve ilk gun 271 olan vaka sayisi ikinci gun 880’e ulasmistir. Ilk gunden itibaren alinan onlemlerle hizla dusen vaka sayisi norovirusun kisiden kisiye bulas ozelligi nedeniyle, 10. gun itibariyle az sayida vaka ile devam etmis ve 28 Temmuz itibariyle beklenen seviyeye inmistir. Salgin suresince 2483 akut gastroenterit vaka basvurusu olmustur. Salgina neden olarak; Daha once uygun duzeylerde seyreden klor duzeyinin tank bosalmasi sonucu bir sure sistemde dusuk duzeyde kalmasi ve ayni donemde bir aydir kullanimda olmayan bir kuyu pompasinin tamirinin bitirilip sistemden yeterince su akitilmadan devreye sokulmasi surecinin superpoze olmasi ile sistemin ana depoda kirlenmesi olarak tespit edilmistir. [TAF Prev Med Bull 2011; 10(5.000: 501-510

  17. Development and evaluation of methods for recovery of Noroviruses from food, water and air

    DEFF Research Database (Denmark)

    Uhrbrand, Katrine

    Noroviruses (NoVs) are the principal cause of viral gastroenteritis worldwide. NoVs are extremely infectious with an estimated infectious dose 50% (ID50) of 18 viral particles. Transmission of NoVs occurs via the faecal-oral route directly through person-to-person contact or indirectly via......, presented in manuscript I-III. Additionally, exposure to airborne NoV transmission and NoV decontamination of food surfaces were addressed in manuscript IV and V, respectively. In manuscript I five methods were compared for the ability to qualitatively recover NoV GII and feline calicivirus (FCV) spiked...... in the digestive tissue of oysters and blue mussels. A method based proteinase K digestion followed by NucliSens miniMAG nucleic acid extraction was found to give the best performance. In a subsequent collaborative trial the method was found to robustly recover the NoV GI, NoV GII and HAV bioaccumulated...

  18. Concentration of Enteroviruses, Adenoviruses, and Noroviruses from Drinking Water by Use of Glass Wool Filters▿

    Science.gov (United States)

    Lambertini, Elisabetta; Spencer, Susan K.; Bertz, Phillip D.; Loge, Frank J.; Kieke, Burney A.; Borchardt, Mark A.

    2008-01-01

    Available filtration methods to concentrate waterborne viruses are either too costly for studies requiring large numbers of samples, limited to small sample volumes, or not very portable for routine field applications. Sodocalcic glass wool filtration is a cost-effective and easy-to-use method to retain viruses, but its efficiency and reliability are not adequately understood. This study evaluated glass wool filter performance to concentrate the four viruses on the U.S. Environmental Protection Agency contaminant candidate list, i.e., coxsackievirus, echovirus, norovirus, and adenovirus, as well as poliovirus. Total virus numbers recovered were measured by quantitative reverse transcription-PCR (qRT-PCR); infectious polioviruses were quantified by integrated cell culture (ICC)-qRT-PCR. Recovery efficiencies averaged 70% for poliovirus, 14% for coxsackievirus B5, 19% for echovirus 18, 21% for adenovirus 41, and 29% for norovirus. Virus strain and water matrix affected recovery, with significant interaction between the two variables. Optimal recovery was obtained at pH 6.5. No evidence was found that water volume, filtration rate, and number of viruses seeded influenced recovery. The method was successful in detecting indigenous viruses in municipal wells in Wisconsin. Long-term continuous filtration retained viruses sufficiently for their detection for up to 16 days after seeding for qRT-PCR and up to 30 days for ICC-qRT-PCR. Glass wool filtration is suitable for large-volume samples (1,000 liters) collected at high filtration rates (4 liters min−1), and its low cost makes it advantageous for studies requiring large numbers of samples. PMID:18359827

  19. Human norovirus surrogate reduction in milk and juice blends by high pressure homogenization.

    Science.gov (United States)

    Horm, Katie Marie; Harte, Federico Miguel; D'Souza, Doris Helen

    2012-11-01

    Novel processing technologies such as high pressure homogenization (HPH) for the inactivation of foodborne viruses in fluids that retain nutritional attributes are in high demand. The objectives of this research were (i) to determine the effects of HPH alone or with an emulsifier (lecithin) on human norovirus surrogates-murine norovirus (MNV-1) and feline calicivirus (FCV-F9)-in skim milk and orange juice, and (ii) to determine HPH effects on FCV-F9 and MNV-1 in orange and pomegranate juice blends. Experiments were conducted in duplicate at 0, 100, 200, 250, and 300 MPa for milk, FCV-F9 was reduced by ≥4 and ∼1.3 log PFU/ml at 300 and 250 MPa, respectively, and ≥4- and ∼1-log PFU/ml reductions were obtained in orange juice at 300 and 250 MPa, respectively. In orange juice or milk combined with lecithin, FCV-F9 was reduced to nondetectable levels at 300 MPa, and by 1.77 and 0.78 log PFU/ml at 250 MPa. MNV-1 in milk was reduced by ∼1.3 log PFU/ml only at 300 MPa, and by ∼0.8 and ∼0.4 log PFU/ml in orange juice at 300 and 250 MPa, respectively. MNV-1 in milk or orange juice containing lecithin at 300 MPa showed 1.32- and 2.5-log PFU/ml reductions, respectively. In the pomegranate-orange juice blend, FCV-F9 was completely reduced, and MNV-1 was reduced by 1.04 and 1.78 log PFU/ml at 250 and 300 MPa, respectively. These results show that HPH has potential for commercial use to inactivate foodborne virus surrogates in juices.

  20. First detection and molecular characterization of sapoviruses and noroviruses with zoonotic potential in swine in Ethiopia.

    Science.gov (United States)

    Sisay, Zufan; Djikeng, Appolinaire; Berhe, Nega; Belay, Gurja; Abegaz, Woldaregay Erku; Wang, Q H; Saif, Linda J

    2016-10-01

    Noroviruses (NoVs) and sapoviruses (SaVs), which belong to the family Caliciviridae, are important human and animal enteric pathogens with zoonotic potential. In Ethiopia, no study has been done on the epidemiology of animal NoVs and SaVs. The aim of this study was to detect and characterize NoVs and SaVs from swine of various ages. Swine fecal samples (n = 117) were collected from commercial farms in Ethiopia. The samples were screened for caliciviruses by reverse transcription polymerase chain reaction (RT-PCR) using universal and genogroup-specific primer pairs. Phylogenetic analysis was conducted using a portion of the RNA-dependent RNA polymerase (RdRp) region and the VP1 region of genome sequences of caliciviruses. Among 117 samples, potential caliciviruses were detected by RT-PCR in 17 samples (14.5 %). Of the RT-PCR-positive fecal samples, four were sequenced, of which two were identified as human NoV GII.1 and the other two as porcine SaV GIII. The porcine SaV strains that were detected were genetically related to the porcine enteric calicivirus Cowden strain genogroup III (GIII), which is the prototype porcine SaV strain. No porcine NoVs were detected. Our results showed the presence of NoVs in swine that are most similar to human strains. These findings have important implications for NoV epidemiology and food safety. Therefore, continued surveillance of NoVs in swine is needed to define their zoonotic potential, epidemiology and public and animal health impact. This is the first study to investigate enteric caliciviruses (noroviruses and sapoviruses) in swine in Ethiopia.

  1. Adsorption characteristics of an enteric virus-binding protein to norovirus, rotavirus and poliovirus

    Directory of Open Access Journals (Sweden)

    Imai Takahiro

    2011-12-01

    Full Text Available Abstract Background Water contamination with human enteric viruses has posed human health risks all over the world. Reasonable and facile methodologies for recovering and quantifying infectious enteric viruses in environmental samples are needed to address the issues of waterborne viral infectious diseases. In this study, a bacterial protein that has a binding capability with several enteric viruses is discovered, and its binding characteristics were investigated for utilizing it as a viral adsorbent in virus recovery and detection technologies. Results A gene of an enteric virus-binding protein (EVBP, derived from a monomer of a bacterial chaperon protein GroEL, was successfully acquired from a genomic DNA library of activated sludge microorganisms with nested PCR. Equilibrium dissociation constants between EVBP and norovirus-like particles (NoVLPs of genotypes GI.7 and GII.4, estimated with quartz crystal microbalance method, were 240 and 210 nM, respectively. These values of equilibrium dissociation constant imply that the binding affinity between EVBP and NoVLPs is 1 to 3-log weaker than that in general antigen-antibody interactions, but about 2-log stronger than that in weak specific interactions of proteins with cations and organic polymers. The adsorptions of EVBP to norovirus, group A rotavirus and poliovirus type 1 were found to be significant in enzyme-linked immunosorbent assay. Meanwhile, the binding of native GroEL tetradecamer to viral particles was weaker than that of EVBP, presumably because of a steric hindrance. The small molecule of EVBP could have an advantage in the access to the surface of viral particles with rugged structure. Conclusions EVBP that has a broad binding spectrum to enteric viruses was newly discovered. The broad binding characteristic of EVBP would allow us to utilize it as a novel adsorbent for detecting diverse enteric viruses in clinical and environmental samples.

  2. Sensibilidad antimicrobiana y caracterización de cepas de Streptococcus pyogenes aisladas de un brote de escarlatina Antimicrobial sensitivity and typing of Streptococcus pyogenes strains isolated during a scarlet fever outbreak

    OpenAIRE

    Alberto González Pedraza-Avilés; Catalina Ortiz-Zaragoza; Ricardo Mota-Vázquez; Ma Eloísa Dickinson-Bannack; Rocío Dávila-Mendoza; Miguel Angel Fernández-Ortega

    2002-01-01

    Objetivo. Evaluar la actividad in vitro de 13 antibióticos contra 47 Streptococcus pyogenes grupo A (SGA). Determinar la presencia de genes que codifican para exotoxina pirogénica estreptocóccica A (SpeA) y serotipos con base en proteína M. Material y métodos. Estudio transversal hecho en el Centro de Salud Dr. José Castro Villagrana sobre un brote de escarlatina en el Colegio Espíritu de América, entre diciembre de 1999 y enero de 2000. El número de niños estudiados fue 137. Se extrajeron po...

  3. 诺如病毒:“完美的人类病原”%Norovirus:a perfect human pathogen

    Institute of Scientific and Technical Information of China (English)

    王丹; 甄珊珊; 汪萱怡

    2015-01-01

    Norovirus is the pathogen causing recent outbreaks of acute viral gastroenteritis in Beijing , Shanghai , Zhejiang and Guangdong in China . This short review introduces the biological and epidemiological characteristics of Norovirus and the current development of vaccine against its infection .%诺如病毒是近来在我国北京、上海、浙江、广东等地导致病毒性胃肠炎暴发的病原体。本文对该病毒的生物学特征与流行病学进行简短综述,并对正在研发的疫苗作介绍。

  4. - Bacillus anthracis, utilización de un Sistema de Información Geográfico (SIG, para el análisis espacio temporal de 54 brotes de carbunclo rural en el partido de Azul, Bs. As., Argentina (Bacillus anthracis, use of a Geographical infoormation Service (GIS, for the temporary space analysis of 54 outbreaks of rural anthax in the county of Azul, Province of Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Vazquez P.

    2006-02-01

    Full Text Available Resumen. El objeto de este trabajo es utilizar un Sistema de Información Geográfico (SIG para el análisis epidemiológico del Carbunclo Rural aplicado a un ecosistema ganadero, integrado por 618.000 bovinos, distribuidos en 1.350 establecimientos del partido de Azul, Provincia de Buenos Aires, Argentina. Esto permitió estudiar hechos epidemiológicos de una enfermedad de antigua data como es el Carbunclo Rural. Su agente causal el Bacillus anthracis, posee la característica de formar esporos que permite mantenerse durante decenas de años en el ambiente com capacidad de transmitir la enfermedad a otrois animales susceptibles. Se describe la metodología para su diagnóstico y los distintos elementos que integran el Sistema de Información Geográfico. Los 54 brotes identificados entre los años 1989 / 2005 fueron georreferenciados para posteriormente relacionarlos con las vías de avenamiento de aguas del partido de Azul, lãs características de sus suelos y la ubicación de las poblaciones de las poblaciones rurales que comparten la zona de isorriesgo. Se plantea un sistema de alerta epidemiológico temprano para establecimientos ganaderos que comparten vías de avenamiento de agua en común con el brote de Carbunclo diagnosticado. El 93 % de los brotes ocurrieron en establecimientos que comparten vías de avenamiento, mientras que el 7 % restante en establecimientos ganaderos ubicados fuera del área de influencia de estas vías Summary. The objjective of this study was the use of a Geographical Information Service (GIS for the epidemiologiacal analysis of rural Anthrax applied to a catle ecosystem, which includes 618.000 cattle, distributed on 1.350 farms in the county of Azul, Province of Buenos Aires, Argentina. This allowed studying long past epidemiological occurrences of a disease such as rural carbuncle Its causing egent is Bacillus anthracis, which has the property of forming spores That permit being maintained dozens of years in

  5. Crystallography of a Lewis-binding norovirus, elucidation of strain-specificity to the polymorphic human histo-blood group antigens.

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    Yutao Chen

    2011-07-01

    Full Text Available Noroviruses, an important cause of acute gastroenteritis in humans, recognize the histo-blood group antigens (HBGAs as host susceptible factors in a strain-specific manner. The crystal structures of the HBGA-binding interfaces of two A/B/H-binding noroviruses, the prototype Norwalk virus (GI.1 and a predominant GII.4 strain (VA387, have been elucidated. In this study we determined the crystal structures of the P domain protein of the first Lewis-binding norovirus (VA207, GII.9 that has a distinct binding property from those of Norwalk virus and VA387. Co-crystallization of the VA207 P dimer with Le(y or sialyl Le(x tetrasaccharides showed that VA207 interacts with these antigens through a common site found on the VA387 P protein which is highly conserved among most GII noroviruses. However, the HBGA-binding site of VA207 targeted at the Lewis antigens through the α-1, 3 fucose (the Lewis epitope as major and the β-N-acetyl glucosamine of the precursor as minor interacting sites. This completely differs from the binding mode of VA387 and Norwalk virus that target at the secretor epitopes. Binding pocket of VA207 is formed by seven amino acids, of which five residues build up the core structure that is essential for the basic binding function, while the other two are involved in strain-specificity. Our results elucidate for the first time the genetic and structural basis of strain-specificity by a direct comparison of two genetically related noroviruses in their interaction with different HBGAs. The results provide insight into the complex interaction between the diverse noroviruses and the polymorphic HBGAs and highlight the role of human HBGA as a critical factor in norovirus evolution.

  6. Genetic mapping of a highly variable norovirus GII.4 blockade epitope: potential role in escape from human herd immunity.

    Science.gov (United States)

    Debbink, Kari; Donaldson, Eric F; Lindesmith, Lisa C; Baric, Ralph S

    2012-01-01

    Noroviruses account for 96% of viral gastroenteritis cases worldwide, with GII.4 strains responsible >80% of norovirus outbreaks. Histo-blood group antigens (HBGAs) are norovirus binding ligands, and antigenic and preferential HBGA binding profiles vary over time as new GII.4 strains emerge. The capsid P2 subdomain facilitates HBGA binding, contains neutralizing antibody epitopes, and likely evolves in response to herd immunity. To identify amino acids regulating HBGA binding and antigenic differences over time, we created chimeric virus-like particles (VLPs) between the GII.4-1987 and GII.4-2006 strains by exchanging amino acids in putative epitopes and characterized their antigenic and HBGA binding profiles using anti-GII.4-1987 and -2006 mouse monoclonal antibodies (MAbs) and polyclonal sera, 1988 outbreak human sera, and synthetic HBGAs. The exchange of amino acids 393 to 395 between GII.4-1987 and GII.4-2006 resulted in altered synthetic HBGA binding compared to parental strains. Introduction of GII.4-1987 residues 294, 297 to 298, 368, and 372 (epitope A) into GII.4-2006 resulted in reactivity with three anti-GII.4-1987 MAbs and reduced reactivity with four anti-GII.4-2006 MAbs. The three anti-GII.4-1987 MAbs also blocked chimeric VLP-HBGA interaction, while an anti-GII.4-2006 blocking antibody did not, indicating that epitope A amino acids comprise a potential neutralizing epitope for GII.4-1987 and GII.4-2006. We also tested GII.4-1987-immunized mouse polyclonal sera and 1988 outbreak human sera for the ability to block chimeric VLP-HBGA interaction and found that epitope A amino acids contribute significantly to the GII.4-1987 blockade response. Our data provide insights that help explain the emergence of new GII.4 epidemic strains over time, may aid development of norovirus therapeutics, and may help predict the emergence of future epidemic strains.

  7. Detection of the pandemic norovirus variant GII.4 Sydney 2012 in Rio Branco, state of Acre, northern Brazil

    Directory of Open Access Journals (Sweden)

    Luciana Damascena da Silva

    2013-12-01

    Full Text Available Noroviruses (NoVs are important cause of gastroenteritis in humans worldwide. Genotype GII.4 is responsible for the majority of outbreaks reported to date. This study describes, for the first time in Brazil, the circulation of NoV GII.4 variant Sydney 2012 in faecal samples collected from children aged less than or equal to eight years in Rio Branco, state of Acre, northern Brazil, during July-September 2012.

  8. An outbreak of norovirus-associated acute gastroenteritis associated with contaminated barrelled water in many schools in Zhejiang, China

    Science.gov (United States)

    Sheng, Minyang; Song, Jianqiang; He, Fan; Qiu, Yinwei; Wu, Haocheng; Lu, Qinbao; Feng, Yan; Lin, Junfen; Chen, Enfu; Chai, Chengliang

    2017-01-01

    Objectives More than 900 students and teachers at many schools in Jiaxing city developed acute gastroenteritis in February 2014. An immediate epidemiological investigation was conducted to identify the pathogen, infection sources and route of transmission. Methods The probable cases and confirmed cases were defined as students or teachers with diarrhoea or vomiting present since the term began in February 2014. An active search was conducted for undiagnosed cases among students and teachers. Details such as demographic characteristics, gastrointestinal symptoms, and drinking water preference and frequency were collected via a uniform epidemiological questionnaire. A case-control study was implemented, and odds ratios (ORs) and 95% confidence intervals were calculated. Rectal swabs from several patients, food handlers and barrelled water factory workers, as well as water and food samples, were collected to test for potential bacteria and viruses. Results A total of 924 cases fit the definition of the probable case, including 8 cases of laboratory-confirmed norovirus infection at 13 schools in Jiaxing city between February 12 and February 21, 2014. The case-control study demonstrated that barrelled water was a risk factor (OR: 20.15, 95% CI: 2.59–156.76) and that bottled water and boiled barrelled water were protective factors (OR: 0.31, 95% CI: 0.13–0.70, and OR: 0.36, 95% CI: 0.16–0.77). A total of 11 rectal samples and 8 barrelled water samples were detected as norovirus-positive, and the genotypes of viral strains were the same (GII). The norovirus that contaminated the barrelled water largely came from the asymptomatic workers. Conclusions This acute gastroenteritis outbreak was caused by barrelled water contaminated by norovirus. The outbreak was controlled after stopping the supply of barrelled water. The barrelled water supply in China represents a potential source of acute gastroenteritis outbreaks due to the lack of surveillance and supervision

  9. Complete Genome Sequence of a Novel Recombinant GII.Pe_GII.17 Norovirus Strain from Hong Kong in 2015.

    Science.gov (United States)

    Chan, Martin C W; Hung, Tin-Nok; Kwok, Kirsty; Chan, Paul K S

    2015-11-12

    The complete genome sequence of a novel recombinant GII.Pe_GII.17 norovirus strain, tentatively named GII.17 Hong Kong 2015, was determined. RNA-dependent RNA polymerase has 95.6% and 98.4% and viral protein 1 has 90.6% and 95.9% identity at the nucleotide and amino acid levels, respectively, to the closest sequences in GenBank.

  10. Inactivation of murine norovirus on a range of copper alloy surfaces is accompanied by loss of capsid integrity.

    Science.gov (United States)

    Warnes, Sarah L; Summersgill, Emma N; Keevil, C William

    2015-02-01

    Norovirus is one of the most common causes of acute viral gastroenteritis. The virus is spread via the fecal-oral route, most commonly from infected food and water, but several outbreaks have originated from contamination of surfaces with infectious virus. In this study, a close surrogate of human norovirus causing gastrointestinal disease in mice, murine norovirus type 1 (MNV-1), retained infectivity for more than 2 weeks following contact with a range of surface materials, including Teflon (polytetrafluoroethylene [PTFE]), polyvinyl chloride (PVC), ceramic tiles, glass, silicone rubber, and stainless steel. Persistence was slightly prolonged on ceramic surfaces. A previous study in our laboratory observed that dry copper and copper alloy surfaces rapidly inactivated MNV-1 and destroyed the viral genome. In this new study, we have observed that a relatively small change in the percentage of copper, between 70 and 80% in copper nickels and 60 and 70% in brasses, had a significant influence on the ability of the alloy to inactivate norovirus. Nickel alone did not affect virus, but zinc did have some antiviral effect, which was synergistic with copper and resulted in an increased efficacy of brasses with lower percentages of copper. Electron microscopy of purified MNV-1 that had been exposed to copper and stainless steel surfaces suggested that a massive breakdown of the viral capsid had occurred on copper. In addition, MNV-1 that had been exposed to copper and treated with RNase demonstrated a reduction in viral gene copy number. This suggests that capsid integrity is compromised upon contact with copper, allowing copper ion access to the viral genome.

  11. Bacterial histo-blood group antigens contributing to genotype-dependent removal of human noroviruses with a microfiltration membrane.

    Science.gov (United States)

    Amarasiri, Mohan; Hashiba, Satoshi; Miura, Takayuki; Nakagomi, Toyoko; Nakagomi, Osamu; Ishii, Satoshi; Okabe, Satoshi; Sano, Daisuke

    2016-05-15

    We demonstrated the genotype-dependent removal of human norovirus particles with a microfiltration (MF) membrane in the presence of bacteria bearing histo-blood group antigens (HBGAs). Three genotypes (GII.3, GII.4, and GII.6) of norovirus-like particles (NoVLPs) were mixed with three bacterial strains (Enterobacter sp. SENG-6, Escherichia coli O86:K61:B7, and Staphylococcus epidermidis), respectively, and the mixture was filtered with an MF membrane having a nominal pore size of 0.45 μm. All NoVLP genotypes were rejected by the MF membrane in the presence of Enterobacter sp. SENG-6, which excreted HBGAs as extracellular polymeric substances (EPS). This MF membrane removal of NoVLPs was not significant when EPS was removed from cells of Enterobacter sp. SENG-6. GII.6 NoVLP was not rejected with the MF membrane in the presence of E. coli O86:K61:B7, but the removal of EPS of E. coli O86:K61:B7 increased the removal efficiency due to the interaction of NoVLPs with the exposed B-antigen in lipopolysaccharide (LPS) of E. coli O86:K61:B7. No MF membrane removal of all three genotypes was observed when S. epidermidis, an HBGA-negative strain, was mixed with NoVLPs. These results demonstrate that the location of HBGAs on bacterial cells is an important factor in determining the genotype-dependent removal efficiency of norovirus particles with the MF membrane. The presence of HBGAs in mixed liquor suspended solids from a membrane bioreactor (MBR) pilot plant was confirmed by immune-transmission electron microscopy, which implies that bacterial HBGAs can contribute to the genotype-dependent removal of human noroviruses with MBR using MF membrane.

  12. Vigilancia epidemiológica de enfermedades transmitidas por alimentos en la provincia de Río Negro, Argentina, 1993-2001 Surveillance of foodborne diseases in the Province of Rio Negro, Argentina, 1993 - 2001

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    Silvana Di Pietro

    2004-04-01

    Full Text Available Se describen 39 brotes de enfermedades transmitidas por alimentos que afectaron a 958 personas en la provincia de Río Negro, Argentina, en el período 1993- 2001. Se identifican los agentes causales, los alimentos involucrados, los sitios de ocurrencia, los factores de riesgo involucrados y los mecanismos de notificación empleados. Salmonella spp (38%, Trichinella spiralis (15%, Escherichia coli (13% y Staphylococcus aureus (15% resultaron los agentes más frecuentes en los brotes. Salmonella spp. también produjo el mayor número de casos (52%. Los principales alimentos involucrados resultaron cárneos (36%, quesos (10%, fiambres y sándwiches (10%, postres (10% y helados (8%. El mayor número de casos, por su parte, fue causado por la ingestión de helados (37%. Con relación al origen de los alimentos, 41% de los brotes fueron causados por comidas elaboradas en los domicilios, 23% en establecimientos comerciales, 13% en fiestas familiares, 8% en fiestas comunitarias y 8% en restaurantes de hoteles. En el 28% de los brotes fue identificado el agente etiológico por análisis epidemiológico exclusivamente, en el 64% se logró el aislamiento del agente, mientras que en el 8% de los casos no se logró el diagnóstico definitivo. Se analiza el valor de la encuesta epidemiológica en los estudios de enfermedades transmitidas por alimentos, la necesidad de fortalecer el sistema de notificación médica de casos y brotes y la importancia de las buenas prácticas en la manipulación de alimentos.A total of 39 outbreaks of foodborne diseases affecting 958 people in the province of Rio Negro, Argentina between 1993 and 2001 are described and evaluated. The main causal agents were identified involving food, sites of occurrence, risk factors and notification system used. Salmonella spp (38%, Trichinella spiralis (15%, Escherichia coli (13% and Staphylococcus aureus (15% were the most frequent agents present in outbreaks. Salmonella spp produced the

  13. Detection of noroviruses in foods: a study on virus extraction procedures in foods implicated in outbreaks of human gastroenteritis.

    Science.gov (United States)

    Rutjes, Saskia A; Lodder-Verschoor, Froukje; van der Poel, Wim H M; van Duijnhoven, Yvonne T H P; de Roda Husman, Ana Maria

    2006-08-01

    Disease outbreaks in which foods are epidemiologically implicated as the common source are frequently reported. Noroviruses and enteric hepatitis A viruses are among the most prevalent causative agents of foodborne diseases. However, the detection of these viruses in foods other than shellfish is often time-consuming and unsuccessful. In this study, three virus concentration methods were compared: polyethylene glycol (PEG) plus NaCl, ultracentrifugation, and ultrafiltration. Two RNA extraction methods, TRIzol and RNeasy Mini Kit (Qiagen), were compared for detection of viruses in whipped cream and lettuce (as representatives of the dairy and vegetable-fruit food groups, respectively). A seeding experiment with canine calicivirus was conducted to determine the efficiency of each virus extraction procedure. The PEG-NaCl-TRIzol method was most efficient for the detection of viruses in whipped cream and the ultracentrifugation-RNeasy-Mini Kit procedure was best for detection on lettuce. Based on the seeding experiments, food items implicated in norovirus-associated gastroenteritis outbreaks were subjected to the optimal procedure for a specific composition and matrix. No noroviruses were detected in the implicated food items, possibly because the concentration of virus on the food item was too low or because of the presence of inhibitory factors. For each food group, a specific procedure is optimal. Inhibitory factors should be controlled in these procedures because they influence virus detection in food.

  14. High sensitive and selective electrochemical biosensor: Label-free detection of human norovirus using affinity peptide as molecular binder.

    Science.gov (United States)

    Hwang, Hye Jin; Ryu, Myung Yi; Park, Chan Young; Ahn, Junki; Park, Hyun Gyu; Choi, Changsun; Ha, Sang-Do; Park, Tae Jung; Park, Jong Pil

    2017-01-15

    Norovirus is known as the major cause of highly infection for gastrointestinal tracts. In this study, robust and highly sensitive biosensors for detecting human norovirus by employing a recognition affinity peptide-based electrochemical platform were described. A series of amino acid-substituted and cysteine-incorporated recognition peptides isolated from evolutionary phage display technique was chemically synthesized and immobilized to a gold sensor layer, the detection performance of the gold-immobilized synthetic peptide-based sensor system was assessed using QCM, CV and EIS. Using EIS, the limit of detection with Noro-1 as a molecular binder was found to be 99.8nM for recombinant noroviral capsid proteins (rP2) and 7.8copies/mL for human norovirus, thereby demonstrating a high degree of sensitivity for their corresponding targets. These results suggest that a biosensor which consists of affinity peptides as a molecular binder and miniaturized microdevices as diagnostic tool could be served as a new type of biosensing platform for point-of-care testing.

  15. Perspectivas de salud ambiental en la investigación de brotes epidémicos asociados con una zona de abastecimiento de aguas de consumo humano Perspectives of environmental health in outbreaks research associated with a zone of consumption water supply human

    Directory of Open Access Journals (Sweden)

    Antonio Lara Villegas

    2004-12-01

    Full Text Available Introducción. El propósito de este trabajo fue estudiar la magnitud, posibles causas y factores ambientales contribuyentes en la aparición de brotes de origen hídrico, en el ámbito de actuación de la localidad de Benaoján (Serranía de Ronda, Málaga.Material y métodos. Análisis de la potabilidad del agua y controles de desinfección. Evaluación del cumplimiento de la calidad del agua potable y requisitos técnico sanitarios de abastecimientos de aguas, conforme a la normativa española sobre aguas de consumo público.Resultados. Se han realizado 110 análisis de potabilidad, comprobando que el 13,4% de las muestras no cumplen con los criterios de potabilidad del agua. Se practicaron 647 controles de desinfección, de los que el 53% resultaron no conformes. El diseño de la red de abastecimiento es del tipo ramificada y al menos presenta 30 ramales ciegos, puntos donde el agua queda estancada. El servicio municipal de aguas no realiza autocontroles de la calidad del agua ni tiene implantados planes generales de higiene de las instalaciones del abastecimiento.Discusión. La investigación ambiental sugiere que la red pública de abastecimiento de aguas es una fuente de infección, problema relacionado con la aparición de brotes epidémicos. Por ello el consumo de agua no tratada debe ser evitado.Introduction. The purpose of this work was studied the magnitude, possible causes and contributing environmental factors in the waterbourne outbreaks appearance, in the performance area of the locality of Benaoján (Town of Málaga, Spain.Material/Methods. Analysis of the potability of the water and disinfection controls. Evaluation of the fulfillment of the quality of the drinking water and sanitary technical requirements of water supplies, pursuant to the Spanish regulation on public consumption waters.Results. We have been accomplished 110 potability analysis, proving that 13,4% of the samples do not comply with the potability criteria of

  16. Brote de shigellosis con 146 casos relacionado con una feria Shigellosis outbreak with 146 cases related to a fair

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    Juan Castell Monsalve

    2008-02-01

    Full Text Available Fundamento: El 3 de septiembre de 2005, el Servicio de Salud Pública de Ciudad Real conoció la existencia de 20 casos de gastroenteritis en el municipio de Daimiel. Se inició una investigación, con los objetivos de determinar las causas y establecer medidas de control. La mayor parte de los afectados eran jóvenes que habían visitado la feria de la localidad. Métodos: Se llevó a cabo un estudio descriptivo y otro analítico de casos y controles. En el descriptivo se incluyeron todas las variables de interés disponibles en las historias clínicas de los pacientes. Se diseñó un estudio de casos y controles apareado por edad (más o menos 5 años, sexo y asistencia a la feria, que incluyó a 65 casos y a 65 controles. Se llevaron a cabo inspecciones de establecimientos y toma de muestras clínicas y de alimentos. Resultados: Se notificaron 196 casos, de los cuales 146 fueron confirmados. La curva epidémica sugiere una fuente común de corta duración. El estudio de casos y controles apareado muestra una asociación con el consumo de patatas con salsa en uno de los chiringuitos (odds ratio [OR] = 20,56; intervalo de confianza [IC] del 95%, 6,15-75,93; p Background: On September 3, 2005, the Ciudad Real Public Health Service (Spain received a report of 20 cases of gastroenteritis in the municipality of Daimiel. We conducted an investigation to determine the cause or causes of the outbreak and to implement control measures. Most of the cases involved young people who visited the municipality's fair. Methods: We carried out a descriptive study and an analytic case-control study. In the descriptive study, all variables of interest available in the medical records were included. In the case-control study, each case was matched with a control by age (plus or minus 5 years, gender, and attendance at the fair. Sixty-five cases and 65 controls were finally included in the study. Samples of foods and stools from food handlers were taken. Results

  17. Conformación de grupos regionales para la investigación y manejo de enfermedades transmisibles por alimentos (ETA’s en Costa Rica

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    Virginia Montero Campos

    Full Text Available El presente proyecto constituyó el fruto del esfuerzo conjunto de tres instituciones comprometidas con el mejoramiento de la calidad de vida de la población costarricense, en el marco de los módulos del programa interamericano de “Liderazgo en Inocuidad de Alimentos” del Instituto Interamericano de Cooperación para la Agricultura (IICA, con el financiamiento del Departamento de Agricultura de Estados Unidos (USDA y la Agencia de Inspección de Alimentos de Canadá (CFIA.Las instituciones involucradas en el desarrollo de este proyecto fueron el Instituto Tecnológico de Costa Rica, por medio del Laboratorio de Servicios Químicos y Microbiológicos (CEQIATEC, el Centro de Referencia en Bacteriología del Instituto de Investigación y Enseñanza en Nutrición y Salud (INCIENSA. La iniciativa del proyecto se basa en que, en los últimos años se ha documentado en nuestro país, la aparición de brotes de diarrea de gran magnitud, asociados al consumo de aguas y/o alimentos contaminados, lo que se ha denominado “Enfermedades Transmisibles por Alimentos” (ETA’s. Durante estos brotes, frecuentemente se ha observado que la capacidad de resolución de los niveles locales en el manejo e investigación de estos es limitada, por lo que en algunas ocasiones no se logra concluir con éxito la investigación relacionada con dicha situación.

  18. Brote epidémico de denguevirus 2, genotipo Jamaica, en Bolivia Epidemic outbreak of dengue virus 2/subgroup Jamaica in Bolivia

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    Alberto Gianella

    1998-11-01

    Full Text Available Objetivo. Confirmar la presencia de brote de dengue en la ciudad de Santa Cruz, Bolivia, así como identificar el denguevirus causal, estimar la tasa de ataque y determinar la proporción de infecciones sintomáticas. Material y métodos. En marzo de 1997 se realizó una encuesta seroepidemiológica con muestreo aleatorio en un distrito céntrico de la ciudad. Se obtuvo información sobre episodios de enfermedad aguda, antecedentes de cuadro febril reciente y muestras de sangre venosa. Se determinó la presencia de IgM antidengue con el método MAC ELISA y se procedió a la tipificación del virus con tecnología de reacción en cadena de la polimerasa. Resultados. Se detectaron anticuerpos IgM en 6.5% de los adultos (IC95% 3.4-9.6 y 5.1% de los niños (IC 95% 2.0-8.2. El virus circulante fue identificado como dengue serotipo 2, genotipo Jamaica. Menos de la mitad de los niños infectados tuvieron una infección sintomática, contra casi 90% de los adultos. Conclusiones. La tasa de ataque estimada es compatible con una epidemia de dengue en Santa Cruz. La introducción del serotipo 2 - Jamaica en el país aumenta el riesgo de dengue hemorrágico.Objective. To confirm an epidemic outbreak of Dengue virus in the city of Santa Cruz, Bolivia, and to determine the serotype of the virus, to estimate the rate of attack and the proportion of symptomatic infections. Material and methods. In March 1997, a seroepidemiological survey was conducted with random sampling in a central district of the city of Santa Cruz, Bolivia. Information on recent acute illness and febrile episodes was gathered, and venous blood samples were obtained. Levels of antidengue IgM were determined by MAC Elisa and the virus was tipified with RT-PCR. Results. IgM antibodies were detected in 6.5% of adults (CI 95% 3.4-9.6 and 5.1% of children (CI 95% 2.0-8.2. Circulating virus was identified as Dengue serotype 2, subgroup Jamaica. Less than half of the infected children experienced

  19. Survival and Transfer of Murine Norovirus within a Hydroponic System during Kale and Mustard Microgreen Harvesting.

    Science.gov (United States)

    Wang, Qing; Kniel, Kalmia E

    2015-11-13

    Hydroponically grown microgreens are gaining in popularity, but there is a lack of information pertaining to their microbiological safety. The potential risks associated with virus contamination of crops within a hydroponic system have not been studied to date. Here a human norovirus (huNoV) surrogate (murine norovirus [MNV]) was evaluated for its ability to become internalized from roots to edible tissues of microgreens. Subsequently, virus survival in recirculated water without adequate disinfection was assessed. Kale and mustard seeds were grown on hydroponic pads (for 7 days with harvest at days 8 to 12), edible tissues (10 g) were cut 1 cm above the pads, and corresponding pieces (4 cm by 4 cm) of pads containing only roots were collected separately. Samples were collected from a newly contaminated system (recirculated water inoculated with ∼3 log PFU/ml MNV on day 8) and from a previously contaminated system. (A contaminated system without adequate disinfection or further inoculation was used for production of another set of microgreens.) Viral titers and RNA copies were quantified by plaque assay and real-time reverse transcription (RT)-PCR. The behaviors of MNV in kale and mustard microgreens were similar (P > 0.05). MNV was detected in edible tissues and roots after 2 h postinoculation, and the levels were generally stable during the first 12 h. Relatively low levels (∼2.5 to ∼1.5 log PFU/sample of both edible tissues and roots) of infectious viruses were found with a decreasing trend over time from harvest days 8 to 12. However, the levels of viral RNA present were higher and consistently stable (∼4.0 to ∼5.5 log copies/sample). Recirculated water maintained relatively high levels of infectious MNV over the period of harvest, from 3.54 to 2.73 log PFU/ml. Importantly, cross-contamination occurred easily; MNV remained infectious in previously contaminated hydroponic systems for up to 12 days (2.26 to 1.00 PFU/ml), and MNV was detected in both

  20. Inactivation of the Tulane Virus, a Novel Surrogate for the Human Norovirus

    Science.gov (United States)

    TIAN, PENG; YANG, DAVID; QUIGLEY, CHRISTINA; CHOU, MARISSA; JIANG, XI

    2014-01-01

    Human noroviruses (HuNoVs) are the major cause of nonbacterial gastroenteritis epidemics. The culturable feline calicivirus and murine norovirus have been used extensively as surrogates to study HuNoV biology, as HuNoV does not grow in vitro. Additional efforts to identify new surrogates are needed, because neither of these common surrogates are truly intestinal pathogens. The newly described Tulane virus (TV) is a typical calicivirus, it is isolated from macaque stools, is cultivable in vitro, and recognizes human histo-blood group antigens. Therefore, TV is a promising surrogate for HuNoVs. In this study, we evaluated the resistance or stability of TV under various physical and environmental conditions by measuring a 50% reduction of tissue culture infective dose (TCID50) by using a TV cell culture system. Due to the nature of this virus, it is hard to produce a high-titer stock through tissue culture. In our study, the maximal reduction in virus titers was 5 D (D = 1 log) in heat-denaturation and EtOH experiments, and 4 D in UV, chlorine, and pH-stability experiments. Therefore in this study, we defined the inactivation of TV as reaching a TCID50/ml of 0 (a 4- to 5-D reduction in TCID50, depending on the detection limit). TV was inactivated after incubation at 63°C for 5 min, incubation at 56°C for 30 min (5 D), exposure to 60 mJ/cm2 of UVC radiation (4 D), or incubation at 300 ppm of free chlorine for 10 min (4 D). TV was shown to be stable from pH 3.0 to 8.0, though an obvious reduction in virus titer was observed at pH 2.5 and 9.0, and was inactivated at pH 10.0 (4 D). TV was resistant to a low concentration of EtOH (40% or lower) but was fully inactivated (5 D) by 50 to 70% EtOH after a short exposure (20 s). In contrast, quantitative real-time PCR was unable to detect, or poorly detected, virus titer reductions between treated and untreated samples described in this study. PMID:23575140

  1. Nonthermal inactivation of norovirus surrogates on blueberries using atmospheric cold plasma.

    Science.gov (United States)

    Lacombe, Alison; Niemira, Brendan A; Gurtler, Joshua B; Sites, Joseph; Boyd, Glenn; Kingsley, David H; Li, Xinhui; Chen, Haiqiang

    2017-05-01

    Viruses are currently the leading cause of foodborne outbreaks, most of which are associated with foods consumed raw. Cold plasma (CP) is an emerging novel nonthermal technology that can be used to surface decontaminate foods. This study investigated CP technology for the nonthermal inactivation of human norovirus surrogates, Tulane virus (TV) and murine norovirus (MNV), on the surface of blueberries. Blueberries (5 g) were weighed into sterile 4 oz. glass jars and inoculated with TV, 5 log PFU/g. Samples were treated with atmospheric CP for 0, 15, 30, 45, and 60 s at a working distance of 7.5 cm with 4 cubic feet/minute (cfm) of CP jet. Temperature readings were taken with an infrared camera prior to, and immediately following, CP treatments. In order to establish the impact of air flow during CP treatment (4 cfm), an additional 7 cfm jet of room temperature air was introduced from a separate nozzle. The experiment was repeated with 90 and 120 s as additional treatment time points. Viral titers were measured immediately after each treatment with a plaque assay using LLC-MK2 cells (TV) or RAW 264.7 cells (MNV). TV was significantly reduced 1.5 PFU/g compared to the control after treatment time of 45s, which was achieved regardless of temperature conditions. With the addition of 7 cfm of ambient air, the maximum log reduction for TV was 3.5 log PFU/g after 120s of treatment. MNV was significantly reduced by 0.5 log PFU/g compare to the control at 15s, and further treatment of MNV with ambient air brought the log reduction to greater than 5 log PFU/g at 90 s of treatment (Fig. 3). These results demonstrate that CP viral inactivation does not rely on thermal inactivation, and is therefore nonthermal in nature. With further optimization, CP may be used by food processors as a means of nonthermal inactivation of foodborne viruses.

  2. Anticuerpos frente a virus West nile y otros virus transmitidos por artropodos en la poblacion del Delta del Ebro

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    Lozano Alvaro

    1998-01-01

    Full Text Available FUNDAMENTOS: El virus West Nile (VWN es un Flavivirus que se transmite al hombre a través de distintas especies de mosquitos y produce brotes y casos esporádicos de enfermedad en distintas regiones del Viejo Mundo, incluída la Cuenca Mediterránea. Las zonas húmedas europeas que acogen aves migratorias procedentes de África constituyen áreas de alto riesgo para esta infección, así como para otras infecciones víricas transmitidas por artrópodos. MÉTODOS: Con objeto de investigar la prevalencia de la infección por el VWN y otros virus de transmisión similar en la población humana del Delta del Ebro, se estudiaron 1037 muestras de suero, obtenidas en 10 localidades de la zona, para presencia de anticuerpos frente a VWN y otros 12 virus transmitidos por artrópodos (3 Alfavirus, 8 Flaviviridae y 1 Bunyaviridae mediante titulación por inhibición de la hemaglutinación (IHA. En algunos casos se estudió la presencia de IgM específica por IHA tras fraccionar el suero por centrifugación en gradientes de sacarosa. RESULTADOS: En total, se encontró reactividad significativa frente a alguno de los virus probados en 130 casos (12.5%; 4.1% frente a Alfavirus, 8.0% frente a Flaviviridae y 0.4% frente a Bunyaviridae. El análisis de los títulos de anticuerpos reveló porcentajes significativos de muestras con títulos elevados frente a antígenos de VWN y otros. La distribución de la seroprevalencia fue muy desigual, concentrándose fundamentalmente en 3 localidades del interior del Delta (Ampolla, San Jaime y Montells, donde la prevalencia de anticuerpos frente a Flaviviridae llegó a alcanzar el 30% y se observaron niveles residuales de IgM frente a VWN en algunos sueros. CONCLUSIONES: Estos resultados y los obtenidos previamente en otras regiones de la Península Ibérica sugieren que el VWN circula en la población humana de las zonas de riesgo y produce brotes epidémicos periódicos. Habida cuenta del alto porcentaje de

  3. [Preventive measures of food poisoning at care facilities for the elderly--current status and problems in food poisoning by noroviruses].

    Science.gov (United States)

    Ezoe, Kumiko; Nagatomi, Hideki; Imaizumi, Iwao

    2012-08-01

    Food poisoning at care facilities for the elderly has been breaking out approximately ten cases per year nationwide from 2001 to 2010. Especially, it reflected the characteristics of food poisoning caused by noroviruses at a high rate. Usually we have been preventing from food poisoning by noroviruses working on existing measures such as temperature control of food materials, sanitary handlings of cooking tools and table wares, and so on. Additionally, the most effective measures to avoid secondary pollution at care facilities for the elderly is that all members at these facilities have to have a sense of crisis about food poisoning by noroviruses and managers at these facilities must take care of health control for all staff.

  4. Scientific Opinion on the risk posed by pathogens in food of non-animal origin. Part 2 (Salmonella and Norovirus in berries

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    EFSA Panel on Biological Hazards (BIOHAZ

    2014-06-01

    Full Text Available Berries are a perishable food which can be consumed as fresh or minimally-processed as well as a frozen ingredient added to many foods. Strawberries, raspberries, blackberries and blueberries are the most commonly consumed in the EU. Risk factors for berry contamination by Salmonella and Norovirus were considered in the context of the whole food chain. Available estimates of the prevalence of these pathogens in berries were evaluated together with mitigation options relating to prevention of contamination and the relevance of microbiological criteria. It was concluded that each farm environment represents a unique combination of risk factors that can influence occurrence and persistence of pathogens in berry production. Appropriate implementation of food safety management systems including Good Agricultural Practices (GAP, Good Hygiene Practices (GHP and Good Manufacturing Practices (GMP, should be primary objectives of berry producers. There is currently insufficient evidence to justify the establishment of microbiological criteria for Salmonella for fresh or frozen berries. Outbreaks associated with Norovirus in frozen raspberries and strawberries are an emerging public health risk, although it is not known if in these outbreaks contamination occurred at minimal processing or during primary production. It is currently not possible to assess the suitability of an EU-wide Norovirus Hygiene Criterion at primary production for raspberries and strawberries. Microbiological criteria for Norovirus in berries are useful for validation and verification of food safety management systems, including HACCP-based processes and procedures, and can be used to communicate to food business operators and other stakeholders what is acceptable or unacceptable, however there is insufficient data to provide a risk base for establishing a Process Hygiene and Food Safety Criteria for Norovirus in berries. Collection of appropriate data and subsequent risk

  5. Lewis histo-blood group α1,3/α1,4 fucose residues may both mediate binding to GII.4 noroviruses.

    Science.gov (United States)

    Nasir, Waqas; Frank, Martin; Koppisetty, Chaitanya A K; Larson, Göran; Nyholm, Per-Georg

    2012-09-01

    Human noroviruses cause recurrent epidemics of gastroenteritis known to be dominated by the clinically important GII.4 genotype which recognizes human Secretor gene-dependent ABH histo-blood group antigens (HBGAs) as attachment factors. There is increasing evidence that GII.4 noroviruses have undergone evolutionary changes to recognize Lewis antigens and non-Secretor saliva. In this study, we have investigated the possibilities of the Lewis α1,3/α1,4 fucoses as mediators of binding of GII.4 noroviruses to Lewis antigens. The study was carried out using molecular dynamics simulations of Lewis type-1 and type-2 chain HBGAs in complex with VA387 P domain dimers in explicit water. Based on the computer simulations, we suggest the possibility of two receptor binding modes for Lewis HBGAs: the "Secretor pose" with the Secretor Fucα1,2 in the binding site and the "Lewis pose" with the Lewis Fucα1,3/α1,4 residues in the binding site. This was further supported by an extensive GlyVicinity analysis of the Protein Data Bank with respect to the occurrence of the Lewis and Secretor poses in complexes of Lewis antigens with lectins and antibodies as well as GII norovirus strains. The Lewis pose can also explain the interactions of GII.4 norovirus strains with Le(x) and SLe(x) structures. Moreover, the present model suggests binding of complex branched polysaccharides, with the Lewis antigens at the nonreducing end, to P domain dimers of GII.4 strains. Our results are relevant for understanding the evolution of norovirus binding specificities and for in silico design of future antiviral therapeutics.

  6. Brote de gripe A H1N1 en la base española de Camp "Arena" (Herat, Afganistán durante julio y agosto de 2009. Parte I: Características clínicas y reducción de la duración de la fiebre con el uso de oseltamivir Outbreak of new influenza a H1N1 in Spanish base Camp "Arena" (Herat, Afghanistan during july and august 2009. Part I: Clinical features and reducing the duration of fever with the use of oseltamivir during the outbreak of new influenza A H1N1 in Spanish forces in Afghanistan

    Directory of Open Access Journals (Sweden)

    F. Maimir Jané

    2011-03-01

    Full Text Available Introducción: Desde la declaración de alerta fase 6 por la OMS se han presentado brotes de gripe A H1N1 en todo el mundo. Presentamos los resultados del estudio realizado en el brote de nueva gripe A H1N1 en la Base Militar de Camp Arena en Herat (Afganistán. Método: Estudio prospectivo de serie de casos, de pacientes controlados por el Servicio de Sanidad del Role 2, valorando la edad, síntomas al ingreso, duración de la fiebre, test de despistaje rápido, complicaciones, intolerancia al oseltamivir. En el grupo inicial de paciente se valoró RT-PCR. Se compararon los grupos con y sin tratamiento con oseltamivir para la duración de la fiebre. Resultados: Estudio de 106 pacientes, con edad media 27,17 años, los síntomas más frecuentes fueron la tos seca y mal estado general. Los pacientes tratados sin oseltamivir presentaron una duración media de la fiebre de 3,71 días, y con oseltamivir de 2,54 días (pIntroduction: Since the warning statement of Phase 6 by WHO, the world has presented Influenza A H1N1 outbreaks. We present the results of the study of a new Influenza A H1N1 outbreak in the Military Base Camp Arena, in Heart (Afghanistan. Methods: Prospective case series of patients monitored by the Health Service of the Role 2, assessing the age, symptoms at admission, duration of fever, rapid screening test, complications, intolerance to oseltamivir. The initial group of patients was evaluated RT-PCR. We compared groups with and without treatment with oseltamivir for the duration of fever. Results: Study of 106 patients, mean age 27.17 years, the most common symptoms were dry cough and general disrepair. Patients without oseltamivir showed an average of 3.71 days of fever and with oseltamivir of 2.54 days (p <0.001. There were a total of 13 complications, the most frequent bronchitis. Intolerance to oseltamivir was presented in 11.29% of patients. Conclusions: Oseltamivir reduces the duration of fever significantly, with onset of

  7. Crystallisation and preliminary X-ray diffraction analysis of the protease from Southampton norovirus complexed with a Michael-acceptor inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Coates, Leighton [ORNL; Cooper, Jon [University of Southampton, England; Hussey, Robert [University of Southampton, England

    2008-01-01

    Noroviruses are the predominant cause of human epidemic nonbacterial gastroenteritis. Viral replication requires a cysteine protease that cleaves a 200 kDa viral polyprotein into its constituent functional parts. Here, the crystallization of the recombinant protease from the Southampton norovirus is described. While the native crystals were found to diffract only to medium resolution (2.9 {angstrom}), cocrystals of an inhibitor complex diffracted X-rays to 1.7 {angstrom} resolution. The polypeptide inhibitor (Ac-EFQLQ-propenyl ethyl ester) possesses an amino-acid sequence designed to match the substrate specificity of the enzyme, but was synthesized with a reactive Michael acceptor group at the C-terminal end.

  8. Antigenic Relatedness of Norovirus GII.4 Variants Determined by Human Challenge Sera.

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    Ying-Chun Dai

    Full Text Available The GII.4 noroviruses (NoVs are a single genotype that is responsible for over 50% of NoV gastroenteritis epidemics worldwide. However, GII.4 NoVs have been found to undergo antigenic drifts, likely selected by host herd immunity, which raises an issue for vaccine strategies against NoVs. We previously characterized GII.4 NoV antigenic variations and found significant levels of antigenic relatedness among different GII.4 variants. Further characterization of the genetic and antigenic relatedness of recent GII.4 variants (2008b and 2010 cluster was performed in this study. The amino acid sequences of the receptor binding interfaces were highly conserved among all GII.4 variants from the past two decades. Using serum samples from patients enrolled in a GII.4 virus challenge study, significant cross-reactivity between major GII.4 variants from 1998 to 2012 was observed using enzyme-linked immunosorbent assays and HBGA receptor blocking assays. The overall abilities of GII.4 NoVs to bind to the A/B/H HBGAs were maintained while their binding affinities to individual ABH antigens varied. These results highlight the importance of human HBGAs in NoV evolution and how conserved antigenic types impact vaccine development against GII.4 variants.

  9. Report of recombinant norovirus GII.g/GII.12 in Beijing, China.

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    Shaowei Sang

    Full Text Available BACKGROUND: Norovirus (NoV has been recognized as the most important cause of nonbacterial acute gastroenteritis affecting all age group people in the world. Genetic recombination is a common occurance in RNA viruses and many recombinant NoV strains have been described since it was first reported in 1997. However, the knowledge of recombinant NoV in China is extremely limited. METHODS: A total of 685 stool specimens were tested for NoV infection from the acute gastroenteritis patients who visited one general hospital in Beijing from April 2009 to November 2011. The virus recombination was identified by constructing phylogenetic trees of two genes, further SimPlot and the maximum chi-square analysis. RESULTS: The overall positive rate was 9.6% (66/685. GII.4 New Orleans 2009 and GII.4 2006b variants were the dominant genotype. Four GII.g/GII.12 and one GII.12/GII.3 recombinant strains were confirmed, and all derived from adult outpatients. The predictive recombination point occurred at the open reading frame (ORF1/ORF2 overlap. CONCLUSIONS: The GII.g ORF1/GII.12ORF2 recombinant has been reported in several countries and it was the first report of this recombinant in China.

  10. Detection and Quantification of Norovirus in Raspberries Implicated in Disease Outbreaks

    DEFF Research Database (Denmark)

    Schultz, Anna Charlotte; Vinje, Jan; Böttiger, Blenda

    2012-01-01

    In recent years, raspberries have emerged as high risk foods for norovirus (NoV) outbreaks. However, the lack of robust and standardized methods has limited our understanding of the level of NoV contamination of raspberries correlated to public health risk. We present an optimized and quality...... controlled protocol for the viral RNA extraction using NucliSens and Plant RNA Isolation Aid and detection by RT-qPCR including bovine serum albumin of NoV in 25 g of raspberries. The protocol was applied on raspberries that had been linked epidemiologically to nine NoV outbreaks which had occurred...... of detection was 119 and 140 RT-qPCR units/25g for NoV GI or GII, respectively. Nineteen (37%) of 51 raspberry samples tested positive for GI and/or GII NoVs with the respective geometric mean values of 70 (range 22-330) or 29 (range 3-217) detectable genome copies/g of raspberries, when corrected using...

  11. Antiviral effects of black raspberry (Rubus coreanus) seed extract and its polyphenolic compounds on norovirus surrogates.

    Science.gov (United States)

    Lee, Ji-Hye; Bae, Sun Young; Oh, Mi; Seok, Jong Hyeon; Kim, Sella; Chung, Yeon Bin; Gowda K, Giri; Mun, Ji Young; Chung, Mi Sook; Kim, Kyung Hyun

    2016-06-01

    Black raspberry seeds, a byproduct of wine and juice production, contain large quantities of polyphenolic compounds. The antiviral effects of black raspberry seed extract (RCS) and its fraction with molecular weight less than 1 kDa (RCS-F1) were examined against food-borne viral surrogates, murine norovirus-1 (MNV-1) and feline calicivirus-F9 (FCV-F9). The maximal antiviral effect was achieved when RCS or RCS-F1 was added simultaneously to cells with MNV-1 or FCV-F9, reaching complete inhibition at 0.1-1 mg/mL. Transmission electron microscopy (TEM) images showed enlarged viral capsids or disruption (from 35 nm to up to 100 nm) by RCS-F1. Our results thus suggest that RCS-F1 can interfere with the attachment of viral surface protein to host cells. Further, two polyphenolic compounds derived from RCS-F1, cyanidin-3-glucoside (C3G) and gallic acid, identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against the viruses. C3G was suggested to bind to MNV-1 RNA polymerase and to enlarge viral capsids using differential scanning fluorimetry and TEM, respectively.

  12. Persistence and Elimination of Human Norovirus in Food and on Food Contact Surfaces: A Critical Review.

    Science.gov (United States)

    Cook, Nigel; Knight, Angus; Richards, Gary P

    2016-07-01

    This critical review addresses the persistence of human norovirus (NoV) in water, shellfish, and processed meats; on berries, herbs, vegetables, fruits, and salads; and on food contact surfaces. The review focuses on studies using NoV; information from studies involving only surrogates is not included. It also addresses NoV elimination or inactivation by various chemical, physical, or processing treatments. In most studies, persistence or elimination was determined by detection and quantification of the viral genome, although improved methods for determining infectivity have been proposed. NoV persisted for 60 to 728 days in water, depending on water source. It also persisted on berries, vegetables, and fruit, often showing 8.0, freeze-drying, and UV radiation. Ineffective disinfectants included hydrogen peroxide, quaternary ammonium compounds, most ethanol-based disinfectants, and antiseptics at normally used concentrations. Thorough washing of herbs and produce was effective in reducing, but not eliminating, NoV in most products. Washing hands with soap generally reduced NoV by <2 log. Recommendations for future research needs are provided.

  13. Characterization of the Genomic Diversity of Norovirus in Linked Patients Using a Metagenomic Deep Sequencing Approach

    Science.gov (United States)

    Nasheri, Neda; Petronella, Nicholas; Ronholm, Jennifer; Bidawid, Sabah; Corneau, Nathalie

    2017-01-01

    Norovirus (NoV) is the leading cause of gastroenteritis worldwide. A robust cell culture system does not exist for NoV and therefore detailed characterization of outbreak and sporadic strains relies on molecular techniques. In this study, we employed a metagenomic approach that uses non-specific amplification followed by next-generation sequencing to whole genome sequence NoV genomes directly from clinical samples obtained from 8 linked patients. Enough sequencing depth was obtained for each sample to use a de novo assembly of near-complete genome sequences. The resultant consensus sequences were then used to identify inter-host nucleotide variations that occur after direct transmission, analyze amino acid variations in the major capsid protein, and provide evidence of recombination events. The analysis of intra-host quasispecies diversity was possible due to high coverage-depth. We also observed a linear relationship between NoV viral load in the clinical sample and the number of sequence reads that could be attributed to NoV. The method demonstrated here has the potential for future use in whole genome sequence analyses of other RNA viruses isolated from clinical, environmental, and food specimens. PMID:28197136

  14. Prevalence and genetic diversity of norovirus among patients with acute diarrhea in Guatemala.

    Science.gov (United States)

    Estévez, Alejandra; Arvelo, Wences; Hall, Aron J; López, María R; López, Beatriz; Reyes, Lissette; Moir, Juan Carlos; Gregoricus, Nicole; Vinjé, Jan; Parashar, Umesh D; Lindblade, Kim A

    2013-07-01

    Noroviruses (NoVs) are a leading cause of acute gastroenteritis outbreaks and sporadic cases of diarrhea in industrialized countries. To study the prevalence and genetic diversity of NoVs in Guatemala, stool specimens were collected from hospitalized and ambulatory patients presenting with diarrhea (≥3 loose or liquid stools in a 24-hr period) who were enrolled in a prospective surveillance system in the Departments of Santa Rosa (October 2007 to August 2010) and Quetzaltenango (August 2009 to August 2010), Guatemala. Specimens were tested for rotavirus, enteric bacteria, and parasites by routine methods and for genogroups I and II NoV by real-time reverse transcription-PCR. A total of 2,403 stool specimens were collected from hospitalized (n = 528) and ambulatory patients (n = 1,875). Overall, 341 (14%) samples tested positive for NoVs including 114 (22%) hospitalized and 227 (12%) ambulatory patients. NoVs disease peaked during the winter (November-January) months. Among the 341 NoVs-positive patients, 32 (9%) were also positive for rotavirus, 32 (9%) for bacteria, and 9 (3%) for protozoa. Nucleotide sequences were obtained from 84 samples collected from hospitalized children aged Guatemala. The findings highlight the need to implement laboratory diagnostics for NoVs to improve appropriate clinical management of diarrheal diseases and guide vaccine development.

  15. Noroviruses in oysters from local markets and oyster farms in southern Thailand.

    Science.gov (United States)

    Kittigul, Leera; Pombubpa, Kannika; Sukonthalux, Suntharee; Rattanatham, Tippawan; Utrarachkij, Fuangfa

    2011-01-01

    One hundred and eighteen oyster samples collected from local markets and oyster farms in southern Thailand were examined for noroviruses (NoVs) and bacterial indicators of fecal contamination (fecal coliforms and Escherichia coli). Using a virus concentration procedure followed by RT-nested PCR, NoVs were detected in 38% of the samples. Oysters collected from oyster farms were found with NoVs at a higher detection rate (25/53 samples) than oysters from local markets (20/65 samples). Of the 45 NoV-positive oyster samples, 67% belonged to NoV genogroup I (GI), 15% to GII, and 18% to both GI and GII. DNA sequencing showed that 2 NoVs belonged to NoV GI-2 genotype. Fecal coliforms in NoV-positive oyster samples were in the range of oyster samples contained fecal coliforms within the standard acceptable level of raw shellfish (oyster samples were within acceptable levels of E. coli contamination (oysters obtained from both markets and oyster farms might pose a potential risk of acute gastroenteritis associated with raw oyster consumption. Examination for both fecal bacterial indicators and enteric viruses should be conducted for microbiological food safety of shellfish.

  16. Norovirus genotypes implicated in two oyster-related illness outbreaks in Ireland.

    Science.gov (United States)

    Rajko-Nenow, P; Keaveney, S; Flannery, J; McINTYRE, A; Doré, W

    2014-10-01

    We investigated norovirus (NoV) concentrations and genotypes in oyster and faecal samples associated with two separate oyster-related outbreaks of gastroenteritis in Ireland. Quantitative analysis was performed using real-time quantitative reverse transcription polymerase chain reaction and phylogenetic analysis was conducted to establish the NoV genotypes present. For both outbreaks, the NoV concentration in oysters was >1000 genome copies/g digestive tissue and multiple genotypes were identified. In faecal samples, GII.13 was the only genotype detected for outbreak 1, whereas multiple genotypes were detected in outbreak 2 following the application of cloning procedures. While various genotypes were identified in oyster samples, not all were successful in causing infection in consumers. In outbreak 2 NoV GII.1 was identified in all four faecal samples analysed and NoV GII concentrations in faecal samples were >108 copies/g. This study demonstrates that a range of NoV genotypes can be present in highly contaminated oysters responsible for gastroenteritis outbreaks.

  17. A Waterborne Gastroenteritis Outbreak Caused by Norovirus GII.17 in a Hotel, Hebei, China, December 2014.

    Science.gov (United States)

    Qin, Meng; Dong, Xiao-Gen; Jing, Yan-Yan; Wei, Xiu-Xia; Wang, Zhao-E; Feng, Hui-Ru; Yu, Hong; Li, Jin-Song; Li, Jie

    2016-09-01

    Norovirus (NoV) is responsible for an estimated 90 % of all epidemic nonbacterial outbreaks of gastroenteritis worldwide. Waterborne outbreaks of NoV are commonly reported. A novel GII.17 NoV strain emerged as a major cause of gastroenteritis outbreaks in China during the winter of 2014/2015. During this time, an outbreak of gastroenteritis occurred at a hotel in a ski park in Hebei Province, China. Epidemiological investigations indicated that one water well, which had only recently been in use, was the probable source. GII.17 NoV was detected by real-time reverse-transcription polymerase chain reaction from samples taken from cases, from concentrated water samples from water well, and from the nearby sewage settling tank. Nucleotide sequences of NoV extracted from clinical and water specimens were genetically identical and had 99 % homology with Beijing/CHN/2015. All epidemiological data indicated that GII.17 NoV was responsible for this outbreak. This is the first reported laboratory-confirmed waterborne outbreak caused by GII.17 NoV genotype in China. Strengthening management of well drinking water and systematica monitoring of NoV is essential for preventing future outbreaks.

  18. Mouse Norovirus infection promotes autophagy induction to facilitate replication but prevents final autophagosome maturation

    Energy Technology Data Exchange (ETDEWEB)

    O’Donnell, Tanya B. [Department of Microbiology and Immunology, at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne 3010 (Australia); Hyde, Jennifer L. [School of Chemical and Biological Sciences, University of Queensland, St. Lucia, Brisbane, Queensland 4072 (Australia); Mintern, Justine D. [Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne 3010 (Australia); Mackenzie, Jason M., E-mail: jason.mackenzie@unimelb.edu.au [Department of Microbiology and Immunology, at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne 3010 (Australia)

    2016-05-15

    Autophagy is a cellular process used to eliminate intracellular pathogens. Many viruses however are able to manipulate this cellular process for their own advantage. Here we demonstrate that Mouse Norovirus (MNV) infection induces autophagy but does not appear to utilise the autophagosomal membrane for establishment and formation of the viral replication complex. We have observed that MNV infection results in lipidation and recruitment of LC3 to the autophagosome membrane but prevents subsequent fusion of the autophagosomes with lysosomes, as SQSTM1 (an autophagy receptor) accumulates and Lysosome-Associated Membrane Protein1 is sequestered to the MNV replication complex (RC) rather than to autophagosomes. We have additionally observed that chemical modulation of autophagy differentially affects MNV replication. From this study we can conclude that MNV infection induces autophagy, however suppresses the final maturation step of this response, indicating that autophagy induction contributes to MNV replication independently of RC biogenesis. - Highlights: • MNV induces autophagy in infected murine macrophages. • MNV does not utilise autophagosomal membranes for replication. • The MNV-induced autophagosomes do not fuse with lysosomes. • MNV sequesters SQSTM1 to prevent autophagy degradation and turnover. • Chemical modulation of autophagy enhances MNV replication.

  19. Enhanced removal of a human norovirus surrogate from fresh vegetables and fruits by a combination of surfactants and sanitizers.

    Science.gov (United States)

    Predmore, Ashley; Li, Jianrong

    2011-07-01

    Fruits and vegetables are major vehicles for transmission of food-borne enteric viruses since they are easily contaminated at pre- and postharvest stages and they undergo little or no processing. However, commonly used sanitizers are relatively ineffective for removing human norovirus surrogates from fresh produce. In this study, we systematically evaluated the effectiveness of surfactants on removal of a human norovirus surrogate, murine norovirus 1 (MNV-1), from fresh produce. We showed that a panel of surfactants, including sodium dodecyl sulfate (SDS), Nonidet P-40 (NP-40), Triton X-100, and polysorbates, significantly enhanced the removal of viruses from fresh fruits and vegetables. While tap water alone and chlorine solution (200 ppm) gave only <1.2-log reductions in virus titer in all fresh produce, a solution containing 50 ppm of surfactant was able to achieve a 3-log reduction in virus titer in strawberries and an approximately 2-log reduction in virus titer in lettuce, cabbage, and raspberries. Moreover, a reduction of approximately 3 logs was observed in all the tested fresh produce after sanitization with a solution containing a combination of 50 ppm of each surfactant and 200 ppm of chlorine. Taken together, our results demonstrate that the combination of a surfactant with a commonly used sanitizer enhanced the efficiency in removing viruses from fresh produce by approximately 100 times. Since SDS is an FDA-approved food additive and polysorbates are recognized by the FDA as GRAS (generally recognized as safe) products, implementation of this novel sanitization strategy would be a feasible approach for efficient reduction of the virus load in fresh produce.

  20. A probabilistic model of norovirus disease burden associated with greywater irrigation of home-produced lettuce in Melbourne, Australia.

    Science.gov (United States)

    Fiona Barker, S; O'Toole, Joanne; Sinclair, Martha I; Leder, Karin; Malawaraarachchi, Manori; Hamilton, Andrew J

    2013-03-01

    The reuse of domestic greywater has become common in Australia, especially during periods of extreme drought. Greywater is typically used in a raw, untreated form, primarily for landscape irrigation, but more than a quarter of greywater users irrigate vegetable gardens with the water, despite government advice against this practice. Greywater can be contaminated with enteric pathogens and may therefore pose a health risk if irrigated produce is consumed raw. A quantitative microbial risk assessment (QMRA) model was constructed to estimate the norovirus disease burden associated with consumption of greywater-irrigated lettuce. The annual disease burdens (95th percentile; DALYs per person) attributed to greywater irrigation ranged from 2 × 10(-8) to 5 × 10(-4), depending on the source of greywater and the existence of produce washing within households. Accounting for the prevalence of produce-washing behaviours across Melbourne, the model predicted annual disease burdens ranging from 4 × 10(-9) for bathroom water use only to 3 × 10(-6) for laundry water use only, and accounting for the proportionate use of each greywater type, the annual disease burden was 2 × 10(-6). We recommend the preferential use of bathroom water over laundry water where possible as this would reduce the annual burden of disease to align with the current Australian recycled water guidelines, which recommend a threshold of 10(-6) DALYs per person. It is also important to consider other exposure pathways, particularly considering the high secondary attack rate of norovirus, as it is highly likely that the estimated norovirus disease burden associated with greywater irrigation of vegetables is negligible relative to household contact with an infected individual.

  1. Perspectivas de la diarrea por rotavirus en El Salvador

    OpenAIRE

    Roberto Arturo Zablah

    2005-01-01

    Materiales y métodos: En diciembre del año 2000, un brote epidémico de gastroenteritis ocurrió en El Salvador que se asoció con numerosas hospitalizaciones y muertes de niños en todo el país. El Ministerio de Salud Pública se mostró preocupado, pues se ignoraba su etiología y las medidas de control usuales fueron ineficaces. El brote lo produjo un rotavirus, y las medidas de control fueron rediseñadas para mejorar el tratamiento con rehidratación oral e iniciar un sistema de vigilancia para c...

  2. Test and validation of methods to sample and detect human virus from environmental surfaces using norovirus as a model virus

    DEFF Research Database (Denmark)

    Ibfelt, T.; Frandsen, T.; Permin, Anders;

    2016-01-01

    Background: Viruses cause a major proportion of human infections, especially gastroenteritis and respiratory infections in children and adults. Indirect transmission between humans via environmental surfaces may play a role in infections, but methods to investigate this have been sparse. Aim...... with a commercial multiplex real-time quantitative polymerase chain reaction detection assay. Findings: Combining the polyester swab with direct lysis allowed recovery down to 100 and 10 genome copies/cm2 of norovirus GI.1 and GII.3, respectively. This procedure resulted in the significant highest recovery of both...

  3. Propagación por estacas y estudio preliminar del establecimiento in vitro de granadilla (Passiflora ligularis, juss

    Directory of Open Access Journals (Sweden)

    Dora Flores

    Full Text Available La granadilla (Passiflora ligularis es una especie de polinización abierta, razón por la cual presenta un alto porcentaje de variabilidad genética. En Costa Rica este cultivo ofrece una opción de diversificación agrícola para la zona de Los Santos y El Guarco de Cartago. El uso de técnicas biotecnológicas como el cultivo de tejidos favorece la explotación de este, ya que permitiría el establecimiento de plantaciones más homogéneas que contribuirían a mejorar el rendimiento y la calidad del fruto. El objetivo de esta investigación fue establecer la metodología de propagación por estacas y realizar un estudio preliminar que conduzca al establecimiento in vitro de material. Se realizaron tres introducciones de estacas al invernadero y es empleado Agrirrot (0,01% AIB para inducir el enraizamiento; se obtuvo un 50% o más de enraizamiento y brotación de las estacas en cada introducción. Para el establecimiento in vitro se introdujeron brotes provenientes de estacas pretratadas en el invernadero. Se obtuvo un 37,5% de explantes muertos por quema, un 50% presentó contaminación fungosa, bacteriana o ambas y un 12,5% de material limpio y brotado.

  4. Empiema por Fusobacterium necrophorum

    OpenAIRE

    ML. Valle Feijoo; M. Rodriguez Arias; A. Cobas Paz; J. De la Fuente Aguado

    2014-01-01

    Resumen La infección sistémica por Fusobacterium necrophorum se caracteriza por la tríada clásica de trombosis de la vena yugular interna, bacteriemia y focos metastásicos y se conoce como Síndrome de Lemierre (SL), sepsis post-angina o necrobacilosis. El compromiso pulmonar precipitado por la embolización séptica es extremadamente común en el SL, sin embargo el F. necrohorum raramente se asila en empiemas sin SL concurrente, por lo que hemos estimado oportuno comunicar un nuevo caso clíni...

  5. Celulitis por citomegalovirus

    OpenAIRE

    2002-01-01

    Las lesiones cutáneas por citomegalovirus (CMV) son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritemato...

  6. Sensitivity of hepatitis A and murine norovirus to electron beam irradiation in oyster homogenates and whole oysters - quantifying the reduction in potential infection risks

    Science.gov (United States)

    Despite worldwide regulations and advisories restricting shellfish harvest to approved locations, consumption of raw oysters continues to be an exposure route for human norovirus (NoV) and hepatitis A virus (HAV). Therefore, a technology that can reduce the public health risks is needed. The focus...

  7. Genome Sequence of Enterobacter cloacae Strain SENG-6, a Bacterium Producing Histo-Blood Group Antigen-Like Substances That Can Bind with Human Noroviruses.

    Science.gov (United States)

    Ishii, Satoshi; Amarasiri, Mohan; Hashiba, Satoshi; Yang, Peiyi; Okabe, Satoshi; Sano, Daisuke

    2016-01-01

    Enterobacter sp. strain SENG-6, isolated from healthy human feces, produces histo-blood group antigen (HBGA)-like substances that can bind with human noroviruses. Based on the genome sequence analysis, strain SENG-6 belongs to the species Enterobacter cloacae The genome sequence of this strain should help identify genes associated with the production of HBGA-like substances.

  8. Norovirus disease associated with excess mortality and use of statins : A retrospective cohort study of an outbreak following a pilgrimage to Lourdes

    NARCIS (Netherlands)

    Rondy, M.; Koopmans, M.; Rotsaert, C.; van Loon, T.; Beljaars, B.; van Dijk, G.; Siebenga, J.; Svraka, S.; Rossen, J. W. A.; Teunis, P.; van Pelt, W.; Verhoef, L.

    2011-01-01

    Although norovirus infection is generally known to be a mild disease, there is some evidence for severe outcome. An outbreak in a Dutch psychiatric institution, originating from pilgrims returning from Lourdes (France), provided an opportunity for performing a retrospective cohort study in order to

  9. Bacterial surface-displayed GII.4 human norovirus capsid proteins bound to surface of Romaine lettuce through HBGA-like molecules

    Science.gov (United States)

    Human Noroviruses (HuNoVs) are the main cause of nonbacterial gastroenteritis. Contaminated produce is a main vehicle for dissemination of HuNoVs. In this study, we used an ice nucleation protein (INP) mediated surface display system to present the protruding domain of GII.4 HuNoV capsid protein (G...

  10. Inactivation of human norovirus surrogates by benzalkonium chloride, potassium peroxymonosulfate, tannic acid, and gallic acid.

    Science.gov (United States)

    Su, Xiaowei; D'Souza, Doris H

    2012-09-01

    Novel methods to effectively disinfect contact surfaces and prevent human norovirus transmission are essential. The effect of benzalkonium chloride (BAC), potassium peroxymonosulfate (KPMS), tannic acid (TA), and gallic acid (GA) on enteric virus surrogates, murine norovirus (MNV-1), feline calicivirus (FCV-F9), and bacteriophage MS2 was studied. Viruses at high (∼7 log₁₀ PFU/mL) or low (∼5 log₁₀ PFU/mL) titers were mixed with equal volumes of BAC (0.2, 0.5, and 1 mg/mL), KPMS (5, 10, and 20 mg/mL), TA (0.02 and 0.2 mg/mL), GA (0.2, 0.4, and 0.8 mg/mL), or water and incubated for 2 h at room temperature. Viral infectivity after triplicate treatments was evaluated using plaque assays in duplicate. Low titers of FCV-F9 and MNV-1 were completely reduced, while low-titer MS2 was reduced by 1.7-1.8 log₁₀ PFU/mL with BAC at all three concentrations. High-titer FCV-F9 was reduced by 2.87, 3.08, and 3.25 log₁₀ PFU/mL, and high-titer MNV-1 was reduced by 1.55, 2.32, and 2.75 log₁₀ PFU/mL with BAC at 0.1, 0.25, and 0.5 mg/mL, respectively. High-titer MS2 was reduced by ∼2 log₁₀ PFU/mL with BAC at all three concentrations. KPMS at all three concentrations reduced high and low titers of FCV-F9 and MS2 and low-titer MNV-1 to undetectable levels, while high-titer MNV-1 was reduced by 0.92 and 3.44 log₁₀ PFU/mL with KMPS at 2.5 and 5 mg/mL, respectively. TA at 0.2 mg/mL only reduced high-titer FCV-F9 by 0.98 log₁₀ PFU/mL and low-titer FCV-F9 by 1.95 log₁₀ PFU/mL. GA at 0.1, 0.2, and 0.4 mg/mL reduced low-titer FCV-F9 by 2.50, 2.36, and 0.86 log₁₀ PFU/mL, respectively with negligible effects against high-titer FCV-F9. BAC and KPMS show promise to be used as broad-spectrum contact surface disinfectants for prevention of noroviral surrogate contamination.

  11. Thermal Inactivation Kinetics of Human Norovirus Surrogates and Hepatitis A Virus in Turkey Deli Meat.

    Science.gov (United States)

    Bozkurt, Hayriye; D'Souza, Doris H; Davidson, P Michael

    2015-07-01

    Human noroviruses (HNoV) and hepatitis A virus (HAV) have been implicated in outbreaks linked to the consumption of presliced ready-to-eat deli meats. The objectives of this research were to determine the thermal inactivation kinetics of HNoV surrogates (murine norovirus 1 [MNV-1] and feline calicivirus strain F9 [FCV-F9]) and HAV in turkey deli meat, compare first-order and Weibull models to describe the data, and calculate Arrhenius activation energy values for each model. The D (decimal reduction time) values in the temperature range of 50 to 72°C calculated from the first-order model were 0.1 ± 0.0 to 9.9 ± 3.9 min for FCV-F9, 0.2 ± 0.0 to 21.0 ± 0.8 min for MNV-1, and 1.0 ± 0.1 to 42.0 ± 5.6 min for HAV. Using the Weibull model, the tD = 1 (time to destroy 1 log) values for FCV-F9, MNV-1, and HAV at the same temperatures ranged from 0.1 ± 0.0 to 11.9 ± 5.1 min, from 0.3 ± 0.1 to 17.8 ± 1.8 min, and from 0.6 ± 0.3 to 25.9 ± 3.7 min, respectively. The z (thermal resistance) values for FCV-F9, MNV-1, and HAV were 11.3 ± 2.1°C, 11.0 ± 1.6°C, and 13.4 ± 2.6°C, respectively, using the Weibull model. The z values using the first-order model were 11.9 ± 1.0°C, 10.9 ± 1.3°C, and 12.8 ± 1.7°C for FCV-F9, MNV-1, and HAV, respectively. For the Weibull model, estimated activation energies for FCV-F9, MNV-1, and HAV were 214 ± 28, 242 ± 36, and 154 ± 19 kJ/mole, respectively, while the calculated activation energies for the first-order model were 181 ± 16, 196 ± 5, and 167 ± 9 kJ/mole, respectively. Precise information on the thermal inactivation of HNoV surrogates and HAV in turkey deli meat was generated. This provided calculations of parameters for more-reliable thermal processes to inactivate viruses in contaminated presliced ready-to-eat deli meats and thus to reduce the risk of foodborne illness outbreaks.

  12. Detection, fate and inactivation of pathogenic norovirus employing settlement and UV treatment in wastewater treatment facilities.

    Science.gov (United States)

    Barrett, M; Fitzhenry, K; O'Flaherty, V; Dore, W; Keaveney, S; Cormican, M; Rowan, N; Clifford, E

    2016-10-15

    It is accepted that discharged wastewaters can be a significant source of pathogenic viruses in receiving water bodies contributing to pollution and may in turn enter the human food chain and pose a risk to human health, thus norovirus (NoV) is often a predominant cause of gastroenteritis globally. Working with NoV poses particular challenges as it cannot be readily identified and detection by molecular methods does not assess infectivity. It has been proposed that the infectivity of NoV may be modelled through the use of an alternative virus; F-specific RNA (FRNA) bacteriophages; GA genotype and other FRNA bacteriophages have been used as a surrogate in studies of NoV inactivation. This study investigated the efficiency of novel pulsed ultraviolet irradiation and low pressure ultraviolet irradiation as a potential pathogen inactivation system for NoV and FRNA bacteriophage (GA) in secondary treated wastewaters. The role of UV dose and the impact of suspended solids concentration on removal efficiency were also examined. The study also investigated the role of settlement processes in wastewater treatment plants in removing NoV. While NoV inactivation could not be determined it was found that at a maximum UV dose of 6.9J/cm(2) (6900mJ/cm(2)) an average 2.4 log removal of FRNA bacteriophage (GA) was observed; indicating the potential need for high UV doses to remove NoV if FRNA bacteriophage prove a suitable indicator for NoV. The study found that increasing concentrations of suspended solids impacted on PUV efficiency however, it appears the extent of the impact may be site specific. Furthermore, the study found that settlement processes can play a significant role in the removal of FRNA bacteriophage, thus potentially NoV.

  13. Herd immunity to GII.4 noroviruses is supported by outbreak patient sera.

    Science.gov (United States)

    Cannon, Jennifer L; Lindesmith, Lisa C; Donaldson, Eric F; Saxe, Lauryn; Baric, Ralph S; Vinjé, Jan

    2009-06-01

    Noroviruses (NoVs) of genogroup II, cluster 4 (GII.4), are the most common cause of outbreaks of acute gastroenteritis worldwide. During the past 13 years, GII.4 NoVs caused four seasons of widespread activity globally, each associated with the emergence of a new strain. In this report, we characterized the most recent epidemic strain, GII.4-2006 Minerva, by comparing virus-like particle (VLP) antigenic relationships and histo-blood group antigen (HBGA) binding profiles with strains isolated earlier. We also investigated the seroprevalence and specificity of GII.4 antibody in the years prior to, during, and following the GII.4 pandemic of 1995 and 1996 using a large collection of acute- and convalescent-phase serum pairs (n = 298) collected from 34 outbreaks. In a surrogate neutralization assay, we measured the blockade of HBGA binding using a panel of GII.4 VLPs representing strains isolated in 1987, 1997, 2002, and 2006 and a GII.3 VLP representing a strain isolated in the mid-1990s. Serum titers required for 50% HBGA blockade were compared between populations. In general, blockade of GII.4 VLP-HBGA binding was greater with convalescent-phase outbreak sera collected near the time of origin of the VLP strain. Heterotypic genotypes did not contribute to herd immunity against GII.4 NoVs based on their inability to block GII.4 VLP binding to HBGA. However, previous exposure to GII.4 NoV followed by infection by GII.3 NoV appeared to evoke an immune response to GII.4 NoV. These results support the hypothesis that herd immunity is a driving force for GII.4 evolution in the U.S. population. The data also suggest that complex patterns of cross-protection may exist across NoV genotypes in humans.

  14. Virucidal effect of cold atmospheric gaseous plasma on feline calicivirus, a surrogate for human norovirus.

    Science.gov (United States)

    Aboubakr, Hamada A; Williams, Paul; Gangal, Urvashi; Youssef, Mohammed M; El-Sohaimy, Sobhy A A; Bruggeman, Peter J; Goyal, Sagar M

    2015-06-01

    Minimal food-processing methods are not effective against foodborne viruses, such as human norovirus (NV). It is important, therefore, to explore novel nonthermal technologies for decontamination of foods eaten fresh, minimally processed and ready-to-eat foods, and food contact surfaces. We studied the in vitro virucidal activity of cold atmospheric gaseous plasma (CGP) against feline calicivirus (FCV), a surrogate of NV. Factors affecting the virucidal activity of CGP (a so-called radio frequency atmospheric pressure plasma jet) were the plasma generation power, the exposure time and distance, the plasma feed gas mixture, and the virus suspension medium. Exposure to 2.5-W argon (Ar) plasma caused a 5.55 log10 unit reduction in the FCV titer within 120 s. The reduction in the virus titer increased with increasing exposure time and decreasing exposure distance. Of the four plasma gas mixtures studied (Ar, Ar plus 1% O2, Ar plus 1% dry air, and Ar plus 0.27% water), Ar plus 1% O2 plasma treatment had the highest virucidal effect: more than 6.0 log10 units of the virus after 15 s of exposure. The lowest virus reduction was observed with Ar plus 0.27% water plasma treatment (5 log10 unit reduction after 120 s). The highest reduction in titer was observed when the virus was suspended in distilled water. Changes in temperature and pH and formation of H2O2 were not responsible for the virucidal effect of plasma. The oxidation of viral capsid proteins by plasma-produced reactive oxygen and nitrogen species in the solution was thought to be responsible for the virucidal effect. In conclusion, CGP exhibits virucidal activity in vitro and has the potential to combat viral contamination in foods and on food preparation surfaces.

  15. Efficacy of three ethanol-based hand rubs against feline calicivirus, a surrogate virus for norovirus.

    Science.gov (United States)

    Kampf, G; Grotheer, D; Steinmann, J

    2005-06-01

    We investigated the efficacy of three ethanol-based hand rubs (Sterillium Virugard, 95% ethanol; Sterillium Rub, 80% ethanol; Desderman N, 75.1% ethanol) against feline calicivirus (FCV), the surrogate virus for norovirus, on artificially contaminated hands of healthy volunteers. The ASTM E 1838-02 standard was used. Experiments were controlled with 70% ethanol and 70% propan-1-ol which were previously found to have maximal efficacy against FCV. In the first step, three different organic loads (5% fetal bovine serum, 5% faecal suspension and the tripartite ASTM load) were compared. A significant influence of the type of organic load was found (P<0.001, ANOVA). In the second step, the hand rubs were investigated with a 5% faecal suspension as a challenging organic load. The hand rub based on 95% ethanol was more effective than those based on 70% ethanol (mean log10 reduction factor: 2.17 vs. 1.56; P=0.17) and 70% propan-1-ol (mean RF: 1.63 vs. 0.95; P=0.0003). The hand rub based on 80% ethanol was also more effective than those based on 70% ethanol (mean RF: 1.25 vs. 1.03: P=0.20) and 70% propan-1-ol (mean RF: 1.43 vs. 1.09; P=0.03). The hand rub based on 75.1% ethanol was less effective than those based on 70% ethanol (mean RF: 1.07 vs. 1.27; P=0.47) and 70% propan-1-ol (mean RF: 0.78 vs. 0.97; P=0.35). Based on our data, ethanol has superior efficacy against FCV than propan-1-ol. In addition, a higher ethanol concentration in three commercially available hand rubs was associated with better efficacy against FCV.

  16. Inhibition of histo-blood group antigen binding as a novel strategy to block norovirus infections.

    Directory of Open Access Journals (Sweden)

    Xu-Fu Zhang

    Full Text Available Noroviruses (NoVs are the most important viral pathogens that cause epidemic acute gastroenteritis. NoVs recognize human histo-blood group antigens (HBGAs as receptors or attachment factors. The elucidation of crystal structures of the HBGA-binding interfaces of a number of human NoVs representing different HBGA binding patterns opens a new strategy for the development of antiviral compounds against NoVs through rational drug design and computer-aided virtual screening methods. In this study, docking simulations and virtual screening were used to identify hit compounds targeting the A and B antigens binding sites on the surface of the capsid P protein of a GII.4 NoV (VA387. Following validation by re-docking of the A and B ligands, these structural models and AutoDock suite of programs were used to screen a large drug-like compound library (derived from ZINC library for inhibitors blocking GII.4 binding to HBGAs. After screening >2 million compounds using multistage protocol, 160 hit compounds with best predicted binding affinities and representing a number of distinct chemical classes have been selected for subsequent experimental validation. Twenty of the 160 compounds were found to be able to block the VA387 P dimers binding to the A and/or B HBGAs at an IC50<40.0 µM, with top 5 compounds blocking the HBGA binding at an IC50<10.0 µM in both oligosaccharide- and saliva-based blocking assays. Interestingly, 4 of the top-5 compounds shared the basic structure of cyclopenta [a] dimethyl phenanthren, indicating a promising structural template for further improvement by rational design.

  17. Burden of acute gastroenteritis, norovirus and rotavirus in a managed care population.

    Science.gov (United States)

    Karve, Sudeep; Krishnarajah, Girishanthy; Korsnes, Jennifer S; Cassidy, Adrian; Candrilli, Sean D

    2014-01-01

    This study assessed and described the episode rate, duration of illness, and health care utilization and costs associated with acute gastroenteritis (AGE), norovirus gastroenteritis (NVGE), and rotavirus gastroenteritis (RVGE) in physician office, emergency department (ED), and inpatient care settings in the United States (US). The retrospective analysis was conducted using an administrative insurance claims database (2006-2011). AGE episode rates were assessed using medical (ICD-9-CM) codes for AGE; whereas a previously published "indirect" method was used in assessing estimated episode rates of NVGE and RVGE. We calculated per-patient, per-episode and total costs incurred in three care settings for the three diseases over five seasons. For each season, we extrapolated the total economic burden associated with the diseases to the US population. The overall AGE episode rate in the physician office care setting declined by 15% during the study period; whereas the AGE episode rate remained stable in the inpatient care setting. AGE-related total costs (inflation-adjusted) per 100 000 plan members increased by 28% during the 2010-2011 season, compared with the 2006-2007 season ($832,849 vs. $1 068 116) primarily due to increase in AGE-related inpatient costs. On average, the duration of illness for NVGE and RVGE was 1 day longer than the duration of illness for AGE (mean: 2 days). Nationally, the average AGE-related estimated total cost was $3.88 billion; NVGE and RVGE each accounted for 7% of this total. The episodes of RVGE among pediatric populations have declined; however, NVGE, RVGE and AGE continue to pose a substantial burden among managed care enrollees. In conclusion, the study further reaffirms that RVGE has continued to decline in pediatric population post-launch of the rotavirus vaccination program and provides RVGE- and NVGE-related costs and utilization estimates which can serve as a resource for researchers and policy makers to conduct cost

  18. Updates on the genetic variations of Norovirus in sporadic gastroenteritis in Chungnam Korea, 2009-2010

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    Park KwiSung

    2012-01-01

    Full Text Available Abstract Previously, we explored the epidemic pattern and molecular characterization of noroviruses (NoVs isolated in Chungnam, Korea in 2008, and the present study extended these observations to 2009 and 2010. In Korea, NoVs showed the seasonal prevalence from late fall to spring, and widely detected in preschool children and peoples over 60 years of age. Epidemiological pattern of NoV was similar in 2008 and in 2010, but pattern in 2009 was affected by pandemic influenza A/H1N1 2009 virus. NoV-positive samples were subjected to sequence determination of the capsid gene region, which resolved the isolated NoVs into five GI (2, 6, 7, 9 and 10 and eleven GII genotypes (1, 2, 3, 4, 6, 7, 8, 12, 13, 16 and 17. The most prevalent genotype was GII.4 and occupied 130 out of 211 NoV isolates (61.6%. Comparison of NoV GII.4 of prevalent genotype in these periods with reference strains of the same genotype was conducted to genetic analysis by a phylogenetic tree. The NoV GII.4 strains were segregated into seven distinct genetic groups, which are supported by high bootstrap values and previously reported clusters. All Korean NoV GII.4 strains belonged to either VI cluster or VII cluster. The divergence of nucleotide sequences within VI and VII intra-clusters was > 3.9% and > 3.5%, respectively. The "Chungnam(06-117/2010" strain which was isolated in June 2010 was a variant that did not belong to cluster VI or VII and showed 5.8-8.2%, 6.2-8.1% nucleotide divergence with cluster VI and VII, respectively.

  19. Aerosolization of a Human Norovirus Surrogate, Bacteriophage MS2, during Simulated Vomiting.

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    Grace Tung-Thompson

    Full Text Available Human noroviruses (NoV are the leading cause of acute gastroenteritis worldwide. Epidemiological studies of outbreaks have suggested that vomiting facilitates transmission of human NoV, but there have been no laboratory-based studies characterizing the degree of NoV release during a vomiting event. The purpose of this work was to demonstrate that virus aerosolization occurs in a simulated vomiting event, and to estimate the amount of virus that is released in those aerosols. A simulated vomiting device was constructed at one-quarter scale of the human body following similitude principles. Simulated vomitus matrices at low (6.24 mPa*s and high (177.5 mPa*s viscosities were inoculated with low (108 PFU/mL and high (1010 PFU/mL concentrations of bacteriophage MS2 and placed in the artificial "stomach" of the device, which was then subjected to scaled physiologically relevant pressures associated with vomiting. Bio aerosols were captured using an SKC Biosampler. In low viscosity artificial vomitus, there were notable differences between recovered aerosolized MS2 as a function of pressure (i.e., greater aerosolization with increased pressure, although this was not always statistically significant. This relationship disappeared when using high viscosity simulated vomitus. The amount of MS2 aerosolized as a percent of total virus "vomited" ranged from 7.2 x 10-5 to 2.67 x 10-2 (which corresponded to a range of 36 to 13,350 PFU total. To our knowledge, this is the first study to document and measure aerosolization of a NoV surrogate in a similitude-based physical model. This has implications for better understanding the transmission dynamics of human NoV and for risk modeling purposes, both of which can help in designing effective infection control measures.

  20. Linking healthcare associated norovirus outbreaks: a molecular epidemiologic method for investigating transmission

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    Andrews Nick

    2006-07-01

    Full Text Available Abstract Background Noroviruses are highly infectious pathogens that cause gastroenteritis in the community and in semi-closed institutions such as hospitals. During outbreaks, multiple units within a hospital are often affected, and a major question for control programs is: are the affected units part of the same outbreak or are they unrelated transmission events? In practice, investigators often assume a transmission link based on epidemiological observations, rather than a systematic approach to tracing transmission. Here, we present a combined molecular and statistical method for assessing: 1 whether observed clusters provide evidence of local transmission and 2 the probability that anecdotally|linked outbreaks truly shared a transmission event. Methods 76 healthcare associated outbreaks were observed in an active and prospective surveillance scheme of 15 hospitals in the county of Avon, England from April 2002 to March 2003. Viral RNA from 64 out of 76 specimens from distinct outbreaks was amplified by reverse transcription-PCR and was sequenced in the polymerase (ORF 1 and capsid (ORF 2 regions. The genetic diversity, at the nucleotide level, was analysed in relation to the epidemiological patterns. Results Two out of four genetic and epidemiological clusters of outbreaks were unlikely to have occurred by chance alone, thus suggesting local transmission. There was anecdotal epidemiological evidence of a transmission link among 5 outbreaks pairs. By combining this epidemiological observation with viral sequence data, the evidence of a link remained convincing in 3 of these pairs. These results are sensitive to prior beliefs of the strength of epidemiological evidence especially when the outbreak strains are common in the background population. Conclusion The evidence suggests that transmission between hospitals units does occur. Using the proposed criteria, certain hypothesized transmission links between outbreaks were supported while

  1. Fast detection of Noroviruses using a real-time PCR assay and automated sample preparation

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    Schmid Michael

    2004-06-01

    Full Text Available Abstract Background Noroviruses (NoV have become one of the most commonly reported causative agents of large outbreaks of non-bacterial acute gastroenteritis worldwide as well as sporadic gastroenteritis in the community. Currently, reverse transcriptase polymerase chain reaction (RT-PCR assays have been implemented in NoV diagnosis, but improvements that simplify and standardize sample preparation, amplification, and detection will be further needed. The combination of automated sample preparation and real-time PCR offers such refinements. Methods We have designed a new real-time RT-PCR assay on the LightCycler (LC with SYBR Green detection and melting curve analysis (Tm to detect NoV RNA in patient stool samples. The performance of the real-time PCR assay was compared with that obtained in parallel with a commercially available enzyme immunoassay (ELISA for antigen detection by testing a panel of 52 stool samples. Additionally, in a collaborative study with the Baden-Wuerttemberg State Health office, Stuttgart (Germany the real-time PCR results were blindly assessed using a previously well-established nested PCR (nPCR as the reference method, since PCR-based techniques are now considered as the "gold standard" for NoV detection in stool specimens. Results Analysis of 52 clinical stool samples by real-time PCR yielded results that were consistent with reference nPCR results, while marked differences between the two PCR-based methods and antigen ELISA were observed. Our results indicate that PCR-based procedures are more sensitive and specific than antigen ELISA for detecting NoV in stool specimens. Conclusions The combination of automated sample preparation and real-time PCR provided reliable diagnostic results in less time than conventional RT-PCR assays. These benefits make it a valuable tool for routine laboratory practice especially in terms of rapid and appropriate outbreak-control measures in health-care facilities and other settings.

  2. Predominance of norovirus and sapovirus in Nicaragua after implementation of universal rotavirus vaccination.

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    Filemón Bucardo

    Full Text Available BACKGROUND: Despite significant reduction of rotavirus (RV infections following implementation of RotaTeq vaccination in Nicaragua, a large burden of patients with diarrhea persists. METHODS: We conducted a community- and hospital-based study of the burden of RV, norovirus (NV and sapovirus (SV infections as cause of sporadic acute gastroenteritis (GE among 330 children ≤ 5 years of age between September 2009 and October 2010 in two major cities of Nicaragua with a RotaTeq coverage rate of 95%. RESULTS: We found that NV, SV and RV infections altogether accounted for 45% of cases of GE. Notably, NV was found in 24% (79/330 of the children, followed by SV (17%, 57/330 and RV (8%, 25/330. The detection rate in the hospital setting was 27%, 15% and 14% for NV, SV and RV respectively, whereas in the community setting the detection rate of RV was < 1%. Among each of the investigated viruses one particular genogroup or genotype was dominant; GII.4 (82% for NV, GI (46% for SV and G1P[8] (64% in RV. These variants were also found in higher proportions in the hospital setting compared to the community setting. The GII.4.2006 Minerva strain circulating globally since 2006 was the most common among genotyped NV in this study, with the GII.4-2010 New Orleans emerging in 2010. CONCLUSIONS: This study shows that NV has become the leading viral cause of gastroenteritis at hospital and community settings in Nicaragua after implementation of RV vaccination.

  3. Trivalent combination vaccine induces broad heterologous immune responses to norovirus and rotavirus in mice.

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    Kirsi Tamminen

    Full Text Available Rotavirus (RV and norovirus (NoV are the two major causes of viral gastroenteritis (GE in children worldwide. We have developed an injectable vaccine design to prevent infection or GE induced with these enteric viruses. The trivalent combination vaccine consists of NoV capsid (VP1 derived virus-like particles (VLPs of GI-3 and GII-4 representing the two major NoV genogroups and tubular RV recombinant VP6 (rVP6, the most conserved and abundant RV protein. Each component was produced in insect cells by a recombinant baculovirus expression system and combined in vitro. The vaccine components were administered intramuscularly to BALB/c mice either separately or in the trivalent combination. High levels of NoV and RV type specific serum IgGs with high avidity (>50% as well as intestinal IgGs were detected in the immunized mice. Cross-reactive IgG antibodies were also elicited against heterologous NoV VLPs not used for immunization (GII-4 NO, GII-12 and GI-1 VLPs and to different RVs from cell cultures. NoV-specific serum antibodies blocked binding of homologous and heterologous VLPs to the putative receptors, histo-blood group antigens, suggesting broad NoV neutralizing activity of the sera. Mucosal antibodies of mice immunized with the trivalent combination vaccine inhibited RV infection in vitro. In addition, cross-reactive T cell immune responses to NoV and RV-specific antigens were detected. All the responses were sustained for up to six months. No mutual inhibition of the components in the trivalent vaccine combination was observed. In conclusion, the NoV GI and GII VLPs combination induced broader cross-reactive and potentially neutralizing immune responses than either of the VLPs alone. Therefore, trivalent vaccine might induce protective immune responses to the vast majority of circulating NoV and RV genotypes.

  4. The burden of norovirus gastroenteritis: an important foodborne and healthcare-related infection.

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    Belliot, G; Lopman, B A; Ambert-Balay, K; Pothier, P

    2014-08-01

    Human norovirus (NoV) is now recognized as one of the most important causative agents of gastroenteritis in all age groups worldwide. During the course of NoV infection, symptoms are usually mild and disappear within 48 h after onset. The incidence of NoV infection is high, with hundreds of cases per 10 000 of the population, although the number of infections is still underestimated. Epidemiological surveys conducted in Europe and North America have shown that NoV infections constitute a major disease burden, especially for young children and the elderly, in whom NoV infection leads to high rates of hospitalization and mortality. NoV infections are also of concern in hospitals, where viral infections can be persistent in immunocompromised patients. Although the cost of NoV infection in the hospital community has not yet been clearly established, it appears that NoV infections could cost hundreds of thousands of euros in terms of unit closure, and NoV-related sickness in patients and health workers. Besides their clinical burden, NoVs, as foodborne pathogens, also cause to millions of dollars of losses for the healthcare system and the food industry. Recent estimates in the USA showed that, annually, NoV illness cost $2 billion and led to a loss of approximately 5000 quality-adjusted life-years, making NoV one of the top five pathogens causing enteric illnesses. The highest cost among 14 foodborne pathogens is also attributed to human NoV in The Netherlands. This accumulation of evidence underlines the enormous impact of NoV on populations.

  5. Postharvest Survival of Porcine Sapovirus, a Human Norovirus Surrogate, on Phytopathogen-Infected Leafy Greens.

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    Esseili, Malak A; Chin, Ashlina; Saif, Linda; Miller, Sally A; Qu, Feng; Lewis Ivey, Melanie L; Wang, Qiuhong

    2015-08-01

    Leafy greens are increasingly being recognized as an important vehicle for human noroviruses (HuNoV), which cause recurring gastroenteritis outbreaks. Leafy greens often become infected by phytopathogens in the field, which may cause symptoms on the edible parts. Whether plant pathogen infections enhance the survival of HuNoV on leafy greens is unknown. Lettuce and spinach plants were infected with a bacterium, Xanthomonas campestris pv. vitians strain 701a, and with Cucumber mosaic virus strain Fny, respectively. The survival rate of porcine sapovirus (SaV), a HuNoV surrogate, on infected and noninfected postharvest leaves was then assessed. In addition, acibenzolar-S-methyl, a commercial chemical elicitor of plant systemic defense, was used to assess whether stimulating the plant host defense affects the postharvest survival of SaV. Leaves harvested from control and treated plants were inoculated with SaV and incubated for 7 days at 4°C. The infectivity (tissue culture infectious dose affecting 50% of the culture [TCID50]/ml) and RNA (genomic equivalent/ml) titers of SaV were assayed using immunohistochemistry staining and SaV-specific TaqMan real-time reverse transcription PCR. Our results showed that cucumber mosaic virus Fny induced mild, nonnecrotic symptoms on spinach leaves and had no effect on SaV survival. In contrast, X. campestris pv. vitians 701a induced small localized necrotic lesions and significantly enhanced SaV survival on lettuce leaves. Treatment with acibenzolar-S-methyl was effective in reducing X. campestris pv. vitians 701a-induced lesions on infected lettuce plants but had no direct effect on SaV survival when used on healthy lettuce plants. These findings indicate that phytopathogen-induced necrotic lesions may enhance the postharvest survival of HuNoV on lettuce leaves. Therefore, preventive measures aiming to maintain healthy plants and minimize preharvest biological damage are expected to improve the safety of leafy greens.

  6. High frequency of porcine norovirus infection in finisher units of Brazilian pig-production systems.

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    Silva, Patrícia F N; Alfieri, Alice F; Barry, Aline F; de Arruda Leme, Raquel; Gardinali, Noemi R; van der Poel, Wim H M; Alfieri, Amauri Alcindo

    2015-01-01

    Norovirus (NoV) is a member of the Caliciviridae family and is considered an emerging human enteric pathogen. NoVs are detected in farm animals such as cattle, sheep and pigs. Porcine NoV (PoNoV) is widespread worldwide, but frequency of infection is often low. This study aimed to investigate the natural PoNoV infection from adult animals of an important Brazilian pig-production region. Faecal samples (n = 112) of asymptomatic pigs aged 9 to 24 weeks old were collected from 16 grower-to-finish herds located in Paraná state, Brazilian Southern region, and evaluated for PoNoV presence. A reverse transcription-polymerase chain reaction (RT-PCR) assay was performed using specific primers that target a conserved region of the virus capsid gene (VP1). PoNoV was detected in 58 (51.8%) of the 112 faecal samples and in 14 (87.5%) of the 16 herds evaluated. Six of the obtained amplicons were submitted to phylogenetic genotyping analysis. The higher nucleotide (86.5-97.4%) and amino acid (100%) similarities of the sequences in this study were with the representative strains of the porcine NoV genogroup II genotype 11 (PoNoV GII-11). These results reveal that PoNoV infection is endemic in one of the most important pork production areas of Brazil and that the PoNoV GII-11 is prevalent in this region.

  7. Prevalence of human noroviruses in frozen marketed shellfish, red fruits and fresh vegetables.

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    Loutreul, Julie; Cazeaux, Catherine; Levert, Delphine; Nicolas, Aline; Vautier, Sandrine; Le Sauvage, Anne Laure; Perelle, Sylvie; Morin, Thierry

    2014-09-01

    Noroviruses (NoVs), currently recognised as the most common human food-borne pathogens, are ubiquitous in the environment and can be transmitted to humans through multiple foodstuffs. In this study, we evaluated the prevalence of human NoV genogroups I (GI) and II (GII) in 493 food samples including soft red fruits (n = 200), salad vegetables (n = 210) and bivalve mollusc shellfish (n = 83), using the Bovine Enterovirus type 1 as process extraction control for the first time. Viral extractions were performed by elution concentration and genome detection by TaqMan Real-Time RT-PCR (RT-qPCR). Experimental contamination using hepatitis A virus (HAV) was used to determine the limit of detection (LOD) of the extraction methods. Positive detections were obtained from 2 g of digestive tissues of oysters or mussels kept for 16 h in seawater containing 2.0-2.7 log10 plaque-forming units (PFU)/L of HAV. For lettuces and raspberries, the LOD was, respectively, estimated at 2.2 and 2.9 log10 PFU per 25 g. Of the molluscs tested, 8.4 and 14.4% were, respectively, positive for the presence of GI NoV and GII NoV RNA. Prevalence in GI NoVs varied from 11.9% for the salad vegetables samples to 15.5% for the red soft fruits. Only 0.5% of the salad and red soft fruits samples were positive for GII NoVs. These results highlight the high occurrence of human NoVs in foodstuffs that can be eaten raw or after a moderate technological processing or treatment. The determination of the risk of infection associated with an RT-qPCR positive sample remains an important challenge for the future.

  8. Protein-RNA linkage and posttranslational modifications of feline calicivirus and murine norovirus VPg proteins

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    Allan Olspert

    2016-06-01

    Full Text Available Members of the Caliciviridae family of positive sense RNA viruses cause a wide range of diseases in both humans and animals. The detailed characterization of the calicivirus life cycle had been hampered due to the lack of robust cell culture systems and experimental tools for many of the members of the family. However, a number of caliciviruses replicate efficiently in cell culture and have robust reverse genetics systems available, most notably feline calicivirus (FCV and murine norovirus (MNV. These are therefore widely used as representative members with which to examine the mechanistic details of calicivirus genome translation and replication. The replication of the calicivirus RNA genome occurs via a double-stranded RNA intermediate that is then used as a template for the production of new positive sense viral RNA, which is covalently linked to the virus-encoded protein VPg. The covalent linkage to VPg occurs during genome replication via the nucleotidylylation activity of the viral RNA-dependent RNA polymerase. Using FCV and MNV, we used mass spectrometry-based approach to identify the specific amino acid linked to the 5′ end of the viral nucleic acid. We observed that both VPg proteins are covalently linked to guanosine diphosphate (GDP moieties via tyrosine positions 24 and 26 for FCV and MNV respectively. These data fit with previous observations indicating that mutations introduced into these specific amino acids are deleterious for viral replication and fail to produce infectious virus. In addition, we also detected serine phosphorylation sites within the FCV VPg protein with positions 80 and 107 found consistently phosphorylated on VPg-linked viral RNA isolated from infected cells. This work provides the first direct experimental characterization of the linkage of infectious calicivirus viral RNA to the VPg protein and highlights that post-translational modifications of VPg may also occur during the viral life cycle.

  9. Norovirus outbreak caused by a new septic system in a dolomite aquifer.

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    Borchardt, Mark A; Bradbury, Kenneth R; Alexander, E Calvin; Kolberg, Rhonda J; Alexander, Scott C; Archer, John R; Braatz, Laurel A; Forest, Brian M; Green, Jeffrey A; Spencer, Susan K

    2011-01-01

    Septic systems that are built in compliance with regulations are generally not expected to be the cause of groundwater borne disease outbreaks, especially in areas with thick vadose zones. However, this case study demonstrates that a disease outbreak can occur in such a setting and outlines the combination of epidemiological, microbiological, and hydrogeological methods used to confirm the source of the outbreak. In early June 2007, 229 patrons and employees of a new restaurant in northeastern Wisconsin were affected by acute gastroenteritis; 6 people were hospitalized. Epidemiological case-control analysis indicated that drinking the restaurant's well water was associated with illness (odds ratio = 3.2, 95% confidence interval = 0.9 to 11.4, P = 0.06). Microbiological analysis (quantitative reverse transcription-polymerase chain reaction) measured 50 genomic copies per liter of norovirus genogroup I in the well water. Nucleotide sequencing determined the genotype as GI.2 and further showed the identical virus was present in patrons' stool specimens and in the septic tank. Tracer tests using dyes injected at two points in the septic system showed that effluent was traveling from the tanks (through a leaking fitting) and infiltration field to the well in 6 and 15 d, respectively. The restaurant septic system and well (85-m deep, in a fractured dolomite aquifer) both conformed to state building codes. The early arrival of dye in the well, which was 188 m from the septic field and located beneath a 35-m thick vadose zone, demonstrates that in highly vulnerable hydrogeological settings, compliance with regulations may not provide adequate protection from fecal pathogens.

  10. A Conserved Interaction between a C-Terminal Motif in Norovirus VPg and the HEAT-1 Domain of eIF4G Is Essential for Translation Initiation.

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    Eoin N Leen

    2016-01-01

    Full Text Available Translation initiation is a critical early step in the replication cycle of the positive-sense, single-stranded RNA genome of noroviruses, a major cause of gastroenteritis in humans. Norovirus RNA, which has neither a 5´ m7G cap nor an internal ribosome entry site (IRES, adopts an unusual mechanism to initiate protein synthesis that relies on interactions between the VPg protein covalently attached to the 5´-end of the viral RNA and eukaryotic initiation factors (eIFs in the host cell. For murine norovirus (MNV we previously showed that VPg binds to the middle fragment of eIF4G (4GM; residues 652-1132. Here we have used pull-down assays, fluorescence anisotropy, and isothermal titration calorimetry (ITC to demonstrate that a stretch of ~20 amino acids at the C terminus of MNV VPg mediates direct and specific binding to the HEAT-1 domain within the 4GM fragment of eIF4G. Our analysis further reveals that the MNV C terminus binds to eIF4G HEAT-1 via a motif that is conserved in all known noroviruses. Fine mutagenic mapping suggests that the MNV VPg C terminus may interact with eIF4G in a helical conformation. NMR spectroscopy was used to define the VPg binding site on eIF4G HEAT-1, which was confirmed by mutagenesis and binding assays. We have found that this site is non-overlapping with the binding site for eIF4A on eIF4G HEAT-1 by demonstrating that norovirus VPg can form ternary VPg-eIF4G-eIF4A complexes. The functional significance of the VPg-eIF4G interaction was shown by the ability of fusion proteins containing the C-terminal peptide of MNV VPg to inhibit in vitro translation of norovirus RNA but not cap- or IRES-dependent translation. These observations define important structural details of a functional interaction between norovirus VPg and eIF4G and reveal a binding interface that might be exploited as a target for antiviral therapy.

  11. [Acute renal failure due to obstructive ureteral stone associated with norovirus gastroenteritis in an infant with congenital solitary kidney].

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    Kato, Taiki; Hamano, Atsushi; Kawamura, Hideki

    2014-10-01

    We report a 35 month-old boy with acute renal failure caused by an obstructive ureteral stone associated with norovirus gastroenteritis. He visited his family physician because of fever, abdominal pain and vomiting. He was diagnosed as acute gastroenteritis. The symptoms relieved once, but abdominal pain and vomiting recurred two days after the visit and the volume of urine decreased. He was diagnosed as norovirus gastoenteritis and acute renal failure which was unresponsive to fluid replacement. Ultrasound study of the abdomen showed a solitary kidney with mild hydronephrosis. He was then admitted to our hospital. He was finally diagnosed as acute postrenal failure due to obstructive ureteral stone with left solitary kidney by abdominal computer tomography (CT). We performed transurethral catheterization immediately. The creatinine and blood urea nitrogen returned to normal level in 2 days. The CT performed on the 28th day post operation showed disappearance of the stone after uric alkalization. Recently, some cases of postrenal failure due to bilateral obstructive ureteral stones, mainly ammonium acid urate stones, associated with viral gastroenteritis were reported. As clinical features, they are common in boys three years or younger after an episode of rotavirus gastroenteritis with high uric acid concentration. By far, the most common cause of acute renal failure in patients with severe gastroenteritis is prerenal failure resulting from hypovolemia. But postrenal cause due to bilateral obstructive stones should be taken in a consideration.

  12. Norovirus Narita 104 Virus-Like Particles Expressed in Nicotiana benthamiana Induce Serum and Mucosal Immune Responses

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    Lolita George Mathew

    2014-01-01

    Full Text Available Narita 104 virus is a human pathogen belonging to the norovirus (family Caliciviridae genogroup II. Noroviruses cause epidemic gastroenteritis worldwide. To explore the potential of developing a plant-based vaccine, a plant optimized gene encoding Narita 104 virus capsid protein (NaVCP was expressed transiently in Nicotiana benthamiana using a tobacco mosaic virus expression system. NaVCP accumulated up to approximately 0.3 mg/g fresh weight of leaf at 4 days postinfection. Initiation of hypersensitive response-like symptoms followed by tissue necrosis necessitated a brief infection time and was a significant factor limiting expression. Transmission electron microscopy of plant-derived NaVCP confirmed the presence of fully assembled virus-like particles (VLPs. In this study, an optimized method to express and partially purify NaVCP is described. Further, partially purified NaVCP was used to immunize mice by intranasal delivery and generated significant mucosal and serum antibody responses. Thus, plant-derived Narita 104 VLPs have potential for use as a candidate subunit vaccine or as a component of a multivalent subunit vaccine, along with other genotype-specific plant-derived VLPs.

  13. Norovirus Narita 104 Virus-Like Particles Expressed in Nicotiana benthamiana Induce Serum and Mucosal Immune Responses

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    Mathew, Lolita George; Herbst-Kralovetz, Melissa M.; Mason, Hugh S.

    2014-01-01

    Narita 104 virus is a human pathogen belonging to the norovirus (family Caliciviridae) genogroup II. Noroviruses cause epidemic gastroenteritis worldwide. To explore the potential of developing a plant-based vaccine, a plant optimized gene encoding Narita 104 virus capsid protein (NaVCP) was expressed transiently in Nicotiana benthamiana using a tobacco mosaic virus expression system. NaVCP accumulated up to approximately 0.3 mg/g fresh weight of leaf at 4 days postinfection. Initiation of hypersensitive response-like symptoms followed by tissue necrosis necessitated a brief infection time and was a significant factor limiting expression. Transmission electron microscopy of plant-derived NaVCP confirmed the presence of fully assembled virus-like particles (VLPs). In this study, an optimized method to express and partially purify NaVCP is described. Further, partially purified NaVCP was used to immunize mice by intranasal delivery and generated significant mucosal and serum antibody responses. Thus, plant-derived Narita 104 VLPs have potential for use as a candidate subunit vaccine or as a component of a multivalent subunit vaccine, along with other genotype-specific plant-derived VLPs. PMID:24949472

  14. Evaluation of survival of murine norovirus-1 during sauerkraut fermentation and storage under standard and low-sodium conditions.

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    Gagné, Marie-Josée; Barrette, Julie; Savard, Tony; Brassard, Julie

    2015-12-01

    Sodium reduction strategies have raised a few concerns in regards to possible outbreaks in unpasteurised raw fermented vegetables. Among potential outbreak agents, foodborne viruses are recognized as an important cause of food-borne illnesses. As most of them are acid-resistant, evaluation of the efficacy of lactic fermentation in inactivating enteric viruses must be considered to ensure the safety of these foods. In particular with the sodium reduction trend which could impair adequate fermentation in vegetables, we have challenged sauerkraut fermentation at a final concentration of 4 log TCID50/mL with the murine norovirus (MNV-1). Three sodium chloride concentrations (1.0%, 1.5%, 2.0%) were evaluated in spontaneous and starter fermentation of sauerkraut and were followed during fermentation and over a storage phase of 90 days. Detection of MNV-1 genetic material was carried out by real-time RT-PCR and the infectivity on cell culture. Real-time RT-PCR results showed that viral RNA was still detected after 90 day in sauerkraut under all the different conditions. Furthermore, MNV-1 viral particles were able to infect RAW cells after 90 days of storage with a non-significant viral charge reduction. Sodium reduction has a significant impact on the fermentation processing of sauerkraut but no influence on the destruction of norovirus particles or on their survival.

  15. Role of hospital surfaces in the transmission of emerging health care-associated pathogens: norovirus, Clostridium difficile, and Acinetobacter species.

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    Weber, David J; Rutala, William A; Miller, Melissa B; Huslage, Kirk; Sickbert-Bennett, Emily

    2010-06-01

    Health care-associated infections (HAI) remain a major cause of patient morbidity and mortality. Although the main source of nosocomial pathogens is likely the patient's endogenous flora, an estimated 20% to 40% of HAI have been attributed to cross infection via the hands of health care personnel, who have become contaminated from direct contact with the patient or indirectly by touching contaminated environmental surfaces. Multiple studies strongly suggest that environmental contamination plays an important role in the transmission of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus spp. More recently, evidence suggests that environmental contamination also plays a role in the nosocomial transmission of norovirus, Clostridium difficile, and Acinetobacter spp. All 3 pathogens survive for prolonged periods of time in the environment, and infections have been associated with frequent surface contamination in hospital rooms and health care worker hands. In some cases, the extent of patient-to-patient transmission has been found to be directly proportional to the level of environmental contamination. Improved cleaning/disinfection of environmental surfaces and hand hygiene have been shown to reduce the spread of all of these pathogens. Importantly, norovirus and C difficile are relatively resistant to the most common surface disinfectants and waterless alcohol-based antiseptics. Current hand hygiene guidelines and recommendations for surface cleaning/disinfection should be followed in managing outbreaks because of these emerging pathogens.

  16. Effect of high hydrostatic pressure processing on norovirus infectivity and genome stability in strawberry puree and mineral water.

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    Kovač, Katarina; Diez-Valcarce, Marta; Raspor, Peter; Hernández, Marta; Rodríguez-Lázaro, David

    2012-01-03

    We report an evaluation of the effect of various combinations of pressures and times on the inactivation of norovirus (NoV) in two types of matrices that are important in NoV transmission: water and soft fruits. The human NoV surrogate murine norovirus was used as the model virus. The effect of HHP on the viral genome was evaluated by using RT real-time PCR (RT-qPCR), and infectivity assay was used to assess effects on the ability of the virus to attach to and replicate in cells. HHP treatments of 400 MPa for 2.5 min proved to be sufficient for efficient inactivation of NoV (>99.9% reduction). The efficacy of viral inactivation was highly dependent on the matrix in which the virus was present. Therefore, the effect of HHP should be carefully studied in all matrices to which HHP could potentially be applied. Finally, we found no consistent correlation between RT-qPCR and virus infectivity results, and consequently RT-qPCR is not a satisfactory tool for predicting risks to human health.

  17. Comparative Inactivation of Murine Norovirus and MS2 Bacteriophage by Peracetic Acid and Monochloramine in Municipal Secondary Wastewater Effluent.

    Science.gov (United States)

    Dunkin, Nathan; Weng, ShihChi; Schwab, Kellogg J; McQuarrie, James; Bell, Kati; Jacangelo, Joseph G

    2017-03-07

    Chlorination has long been used for disinfection of municipal wastewater (MWW) effluent while the use peracetic acid (PAA) has been proposed more recently in the United States. Previous work has demonstrated the bactericidal effectiveness of PAA and monochloramine in wastewater, but limited information is available for viruses, especially ones of mammalian origin (e.g., norovirus). Therefore, a comparative assessment was performed of the virucidal efficacy of PAA and monochloramine against murine norovirus (MNV) and MS2 bacteriophage in secondary effluent MWW and phosphate buffer (PB). A suite of inactivation kinetic models was fit to the viral inactivation data. Predicted concentration-time (CT) values for 1-log10 MS2 reduction by PAA and monochloramine in MWW were 1254 and 1228 mg-min/L, respectively. The 1-, 2-, and 3-log10 model predicted CT values for MNV viral reduction in MWW were 32, 47, and 69 mg-min/L for PAA and 6, 13, and 28 mg-min/L for monochloramine, respectively. Wastewater treatment plant disinfection practices informed by MS2 inactivation data will likely be protective for public health but may overestimate CT values for reduction of MNV. Additionally, equivalent CT values in PB resulted in greater viral reduction which indicate that viral inactivation data in laboratory grade water may not be generalizable to MWW applications.

  18. Aspectos clínicos, serológicos y parasitológicos de un brote de triquinelosis humana en Villa Mercedes, San Luis, Argentina: Las fases aguda y cronica de la infección Clinical, serological and parasitological aspects of an outbreak of human trichinellosis in Villa Mercedes, San Luis, Argentina. The acute and chronic phases of the infection

    Directory of Open Access Journals (Sweden)

    Marcela A. Calcagno

    2005-08-01

    Full Text Available Se describen las características clínicas y serológicas de individuos cursando las fases aguda (n: 54 y crónica (n: 32 de triquinelosis, de un brote epidémico ocurrido en una zona endémica de Argentina, originado por el consumo de productos de cerdo de origen comercial. Se evaluaron los datos epidemiológicos, signos y síntomas de la parasitosis y estudios de laboratorio. Se realizaron estudios parasitológicos en pacientes y en chacinados. Los resultados mostraron que: a la carga parasitaria de los productos de cerdo fue de 200.0±18.3 larvas/g; b se demostró la presencia de larvas musculares en 10 de 11 pacientes estudiados; c durante la fase aguda se observó fiebre (94%, eosinofilia (90%, mialgias (85%, cefalea (81%, edema facial (54%, diarrea (52% y anticuerpos anti-Trichinella (64%; d el 15% de los pacientes debió ser hospitalizado presentando el 7% de ellos complicaciones; e durante la fase crónica se observó mialgia (72%, alteraciones visuales (22%, desórdenes gastrointestinales (31% y la persistencia de anticuerpos (77%. Este estudio evidencia el impacto socioeconómico de la triquinelosis debido a las características clínicas de la fase aguda y a la presencia de síntomas en la fase crónica.Clinical and serological features of individuals undergoing the acute (n: 54 and chronic (n: 32 phases of trichinellosis belonging to an outbreak originated by the consumption of pork products of a commercial source, arisen in Argentina, are described. Epidemiological data, signs, symptoms, and laboratory studies were assessed. Parasitological studies were performed in patients and pork products. Results showed that: a the parasite burden of pork products was 200.0±18.3 larvae/g; b muscle larvae were demonstrated in 10 out of the 11 patients studied; c during the acute phase, fever (94%, eosinophilia (90%, myalgia (85%, headache (81%, facial edema (54%, diarrhoea (52% and anti-Trichinella antibodies (64% were observed; d 15% of the

  19. Caracterización epidemiológica, clínica y microbiológica del brote de diarrea asociado a Clostridium difficile, ocurrido en el Hospital San Juan de Dios, 2008-2009 Epidemiologic, clinical, and microbiologic description of an outbreak of Clostridium difficile associated diarrhea in Costa Rica

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    Manuel Antonio Villalobos-Zúñiga

    2012-09-01

    Full Text Available Antecedentes: la enfermedad diarreica asociada a Clostridium difficile (EDACD es la causa más importante de diarrea nosocomial en el mundo. En Costa Rica, se presentó recientemente un brote de EDACD en el Hospital San Juan de Dios de San José, hospital de tercer nivel con 700 camas. En el estudio se analizan las características epidemiológicas, clínicas y microbiológicas de los pacientes con EDACD atendidos entre noviembre de 2008 y junio de 2009. Pacientes y métodos: se definió como caso de EDACD un paciente con cuadro diarréico con detección de ELISA positiva por toxina A de C. difficile en heces. Se realizó un análisis de la incidencia anual desde 2004 de EDACD, y de la incidencia mensual de EDACD en 2009 en el HSJD, así como un estudio observacional y retrospectivo de 112 expedientes médicos correspondientes a pacientes con el diagnóstico de EDACD atendidos en el Hospital, en el periodo comprendido entre el 15 de noviembre de 2008 y el 15 de junio de 2009. El análisis de los datos se efectuó mediante pruebas estadísticas descriptivas y medidas de asociación. Resultados: la incidencia de EDACD aumentó desde finales de 2008, y alcanzó su pico máximo en abril de 2009, cuando se implementaron medidas sanitarias que disminuyeron en un 75% el número de pacientes en 8 meses. De los 112 expedientes médicos revisados, 63 (56% fueron hombres. La edad promedio fue de 65,33 años; 103 (92% pacientes desarrollaron su enfermedad mientras estuvieron hospitalizados; el tiempo promedio de internamiento fue de 18,6 días. Solo el 9% no presentó ninguna comorbilidad. Las comorbilidades más frecuentes fueron: HTA y DM tipo 2, con un 57,5% y un 39,8%, respectivamente, y enfermedad neuropsiquiátrica en un 29,2%. El 96% (107 pacientes había recibido tres o más antibióticos antes del inicio de la diarrea. La duración promedio de la antibióticoterapia fue de 32 días por paciente. En promedio, la duración de la diarrea fue de 10,2 d

  20. EFSA BIOHAZ Panel (EFSA Panel on Biological Hazards), 2014. Scientific Opinion on the risk posed by pathogens in food of non-animal origin. Part 2 (Salmonella and Norovirus in tomatoes)

    OpenAIRE

    2014-01-01

    Tomatoes may be minimally processed to obtain ready-to-eat products, and these steps include selection, washing, cleaning, stem removal, cutting, packaging and storage. Epidemiological data from the EU have identified one salmonellosis outbreak and one Norovirus outbreak associated with tomato consumption between 2007 and 2012. Risk factors for tomato contamination by Salmonella and Norovirus were considered in the context of the whole food chain. Available estimates of the Salmonella and Nor...

  1. Celulitis por citomegalovirus

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    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

  2. Angioedema por rellenos faciales: Descripción de cinco casos

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    Micaela A. Cosatti

    2010-12-01

    Full Text Available En los últimos años se ha incrementado la utilización de sustancias de relleno facial con fines estéticos. Estos productos, originalmente considerados inertes, se asocian con diversos efectos adversos localizados alrededor del sitio de la aplicación. Describimos a 5 mujeres con antecedentes de inyecciones de sustancia de relleno facial que presentaron como síntoma inicial angioedema facial duro y persistente seguido por la aparición de nódulos subcutáneos. Todas las pacientes fueron derivadas al servicio de alergia por sospecha de angioedema de causa alérgica sin respuesta al tratamiento con antihistamínicos. El angioedema inició 27.6 meses (1 a 48 luego de la inyección del producto, y las pacientes evolucionaron con brotes y remisiones que fueron tratados con corticoides orales y en 2 oportunidades con inyecciones locales. El tiempo medio desde el inicio de los síntomas hasta la remisión del angioedema fue 8.75 meses (1 a 24. A octubre de 2009 cuatro pacientes se mantuvieron en remisión persistente, luego de un seguimiento clínico de 24.5 meses (7 a 36. Una paciente continúa con exacerbaciones luego de 11 meses de iniciados los síntomas. Las sustancias de relleno facial pueden producir angioedema como evento adverso y deben ser consideradas en el diagnóstico diferencial del angioedema persistente. Sólo responden al tratamiento con esteroides y en algunos casos esteroides dependientes, con ciclosporina. La frecuencia de angioedema por rellenos faciales entre pacientes con angioedema asistidos en la Unidad de Asma, Alergia e Inmunología Clínica fue del 0.5%.

  3. Norovirus diversity in diarrheic children from an African-descendant settlement in Belem, Northern Brazil.

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    Glicélia Cruz Aragão

    Full Text Available Norovirus (NoV, sapovirus (SaV and human astrovirus (HAstV are viral pathogens that are associated with outbreaks and sporadic cases of gastroenteritis. However, little is known about the occurrence of these pathogens in relatively isolated communities, such as the remnants of African-descendant villages ("Quilombola". The objective of this study was the frequency determination of these viruses in children under 10 years, with and without gastroenteritis, from a "Quilombola" Community, Northern Brazil. A total of 159 stool samples were obtained from April/2008 to July/2010 and tested by an enzyme immunoassay (EIA and reverse transcription-polymerase chain reaction (RT-PCR to detect NoV, SaV and HAstV, and further molecular characterization was performed. These viruses were detected only in the diarrheic group. NoV was the most frequent viral agent detected (19.7%-16/81, followed by SaV (2.5%-2/81 and HAstV (1.2%-1/81. Of the 16 NoV-positive samples, 14 were sequenced with primers targeting the B region of the polymerase (ORF1 and the D region of the capsid (ORF2. The results showed a broad genetic diversity of NoV, with 12 strains being classified as GII-4 (5-41.7%, GII-6 (3-25%, GII-7 (2-16.7%, GII-17 (1-8.3% and GI-2 (1-8.3%, as based on the polymerase region; 12 samples were classified, based on the capsid region, as GII-4 (6-50%, being 3-2006b variant and 3-2010 variant, GII-6 (3-25%, GII-17 (2-16.7% and GII-20 (1-8.3%. One NoV-strain showed dual genotype specificity, based on the polymerase and capsid region (GII-7/GII-20. This study provides, for the first time, epidemiological and molecular information on the circulation of NoV, SaV and HAstV in African-descendant communities in Northern Brazil and identifies NoV genotypes that were different from those detected previously in studies conducted in the urban area of Belém. It remains to be determined why a broader NoV diversity was observed in such a semi-isolated community.

  4. Norovirus GII.4 detection in environmental samples from patient rooms during nosocomial outbreaks.

    Science.gov (United States)

    Nenonen, Nancy P; Hannoun, Charles; Svensson, Lennart; Torén, Kjell; Andersson, Lars-Magnus; Westin, Johan; Bergström, Tomas

    2014-07-01

    Norovirus (NoV) is an important cause of nosocomial gastroenteric outbreaks. This 5-month study was designed to characterize NoV contamination and airborne dispersal in patient rooms during hospital outbreaks. Air vents, overbed tables, washbasins, dust, and virus traps designed to collect charged particles from the air were swabbed to investigate the possibility of NoV contamination in patient rooms during outbreaks in seven wards and in an outbreak-free ward. Symptomatic inpatients were also sampled. Nucleic acid extracts of the samples were examined for NoV RNA using genogroup I (GI) and GII real-time reverse transcription-PCR (RT-PCR). The NoV strains were characterized by RT-PCR, sequencing, and phylogenetic analysis of the RNA-dependent RNA-polymerase-N/S capsid-coding region (1,040 nucleotides [nt]). Patient strains from two outbreaks in one ward were sequenced across the RNA-dependent-RNA-polymerase major capsid-coding region (2.5 kb), including the hypervariable P2 domain. In the outbreak wards, NoV GII was detected in 48 of 101 (47%) environmental swabs and 63 of 108 patients (58%); NoV genotype II.4 was sequenced from 18 environmental samples, dust (n = 8), virus traps (n = 4), surfaces (n = 6), and 56 patients. In contrast, NoV GII was detected in 2 (GII.4) of 28 (7%) environmental samples and in 2 (GII.6 and GII.4) of 17 patients in the outbreak-free ward. Sequence analyses revealed a high degree of similarity (>99.5%, 1,040 nt) between NoV GII.4 environmental and patient strains from a given ward at a given time. The strains clustered on 11 subbranches of the phylogenetic tree, with strong correlations to time and place. The high nucleotide similarity between the NoV GII.4 strains from patients and their hospital room environment provided molecular evidence of GII.4 dispersal in the air and dust; therefore, interventional cleaning studies are justified.

  5. Epidemiological and virological investigation of a Norovirus outbreak in a resort in Puglia, Italy

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    Coscia Maria

    2007-11-01

    Full Text Available Abstract Background This paper describes the third large outbreak of Norovirus (NoV gastroenteritis reported in the Southern Italy region of Puglia. Methods A matched case control study was conducted, on 19 July 2005, for investigating risk factors, using a structured questionnaire on food consumption. A multivariate analysis was conducted to estimate the adjusted Odds Ratios. Laboratory and environmental investigation were also performed. Results On the day of the study 41 cases were identified and 41 controls were enrolled. Controls were matched for age and gender. The mean age of the cases was 26 years old, and 58% were female. The clinical pattern of the disease was characterised by the presence of diarrhoea (95%, vomiting (70%, abdominal pain (51% and fever (32%. Of the 41 cases included in the study, the majority (65% were residents of Northern Italian regions. No food samples were available for testing. The matched univariate analysis revealed that cases were more likely to have consumed raw mussels, eggs or ice cubes made of tap water than controls. In the multivariate conditional logistic regression analysis, having eaten raw mussels or ice became more strongly associated with illness. All of the 20 faecal samples collected were tested for NoVs. Eighteen stools (90% of total examined were positive by RT-PCR, and sequence analysis performed onto 3 samples confirmed the presence of a GGII NoV. No test specific for NoV was performed on water or food samples. Conclusion The most likely hypothesis supported by the findings of the epidemiological investigation was that illness was associated with raw mussels and ice, made with tap water. These hypothesis could not be confirmed by specific microbiologic testing for NoV in food or ice. The lack of clear knowledge of NoV as a major causative agent of epidemic outbreaks of gastroenteritis in Italy is due to the absence of timely reporting of the cases to the local public health offices and the

  6. A quantitative exposure model simulating human norovirus transmission during preparation of deli sandwiches.

    Science.gov (United States)

    Stals, Ambroos; Jacxsens, Liesbeth; Baert, Leen; Van Coillie, Els; Uyttendaele, Mieke

    2015-03-02

    Human noroviruses (HuNoVs) are a major cause of food borne gastroenteritis worldwide. They are often transmitted via infected and shedding food handlers manipulating foods such as deli sandwiches. The presented study aimed to simulate HuNoV transmission during the preparation of deli sandwiches in a sandwich bar. A quantitative exposure model was developed by combining the GoldSim® and @Risk® software packages. Input data were collected from scientific literature and from a two week observational study performed at two sandwich bars. The model included three food handlers working during a three hour shift on a shared working surface where deli sandwiches are prepared. The model consisted of three components. The first component simulated the preparation of the deli sandwiches and contained the HuNoV reservoirs, locations within the model allowing the accumulation of NoV and the working of intervention measures. The second component covered the contamination sources being (1) the initial HuNoV contaminated lettuce used on the sandwiches and (2) HuNoV originating from a shedding food handler. The third component included four possible intervention measures to reduce HuNoV transmission: hand and surface disinfection during preparation of the sandwiches, hand gloving and hand washing after a restroom visit. A single HuNoV shedding food handler could cause mean levels of 43±18, 81±37 and 18±7 HuNoV particles present on the deli sandwiches, hands and working surfaces, respectively. Introduction of contaminated lettuce as the only source of HuNoV resulted in the presence of 6.4±0.8 and 4.3±0.4 HuNoV on the food and hand reservoirs. The inclusion of hand and surface disinfection and hand gloving as a single intervention measure was not effective in the model as only marginal reductions of HuNoV levels were noticeable in the different reservoirs. High compliance of hand washing after a restroom visit did reduce HuNoV presence substantially on all reservoirs. The

  7. Estudio epidemiológico de los brotes de gastroenteritis aguda de etología vírica en Cataluña

    OpenAIRE

    Torner Gràcia, Núria

    2008-01-01

    La gastroenteritis aguda es un problema de salud, constituyendo la primera causa de morbilidad y de mortalidad en la población infantil en los países en vías de desarrollo. En países desarrollados cerca del 10% de las hospitalizaciones en menores de 5 años se produce por esta causa. Afecta también a los adultos y especialmente a los ancianos, suponiendo el segundo o tercer motivo de consulta en servicios sanitarios de todo tipo. Las gastroenteritis agudas pueden estar causadas por bacterias, ...

  8. An epidemiological study on the norovirus detected in the field environment after an outbreak of norovirus gastroenteritis%诺如病毒胃肠炎暴发后环境中病毒检测情况分析

    Institute of Scientific and Technical Information of China (English)

    周晓红; 李晖; 杨杏芬; 柯昌文; 钟豪杰; 孙立梅; 郭汝宁

    2010-01-01

    Objective To study the status of norovirus in environment of the patient's residence and water samples after a norovirus gastroenteritis outbreak, to provide evidences for the development of strategies for prevention and control of the disease. Methods After a norovirus gastroenteritis outbreak, anus swabs from the patient, swabs from the household environment and the water samples were collected to detect the norovirus by RT-PCR methods. Sequencing analysis was conducted on those positive specimens. Results Three specimens of the anus swabs from 9 patients and 2 samples of the 46 house environment swabs were positive to the virus. The latter were from the surface of water-closets of two families that the illness were asymptomatic. Among 5 water samples, only one was positive, which was the rivulet water that the feces of the villagers evacuated directly. Results showed that the sequences of the virus detected from the anus swabs of the patients, the swabs from the household environment and the samples of the rivulet water belonged to the same species. Conclusion It is necessary to strengthen activities as supervision and disinfection to the feces of the patients, especially on monitoring the feces that might have contaminated the water during the noroviru gastroenteritis outbreak.%目的 了解诺如病毒胃肠炎暴发后,病例临床症状消失、末例病例发病日期经过最长潜伏期(72 h)且无续发病例的情况下,病例家庭环境及外环境水标本中病毒存在情况.方法 在末例病例发病日期经过最长潜伏期(72h)后,采集病例肛拭标本、家庭环境标本、外环境水标本,采用RT-PCR方法 检测病毒,阳性标本测序分析.结果 9份病例肛拭标本中3份呈阳性;46份家庭环境拭子中2份呈阳性,分别是来自两户已无现症病例的家庭厕所马桶表面;5份外环境水标本中1份呈阳性,即村民粪便直接排入的河涌.病例肛拭、家庭环境拭子及河涌水三者检出的病

  9. Detection of norovirus in oyster by real time RT-PCR%应用荧光定量RT-PCR法检测牡蛎中诺如病毒

    Institute of Scientific and Technical Information of China (English)

    邓丽丽; 刘巍; 莫建光; 谭冬梅; 谢镇国; 唐振柱; 董柏青

    2011-01-01

    目的 建立牡蛎样品中的诺如病毒检测方法.方法 优化甘氨酸缓冲液处理牡蛎匀浆液,摸索PEG沉淀浓缩病毒的浓度,提取病毒RNA,采用荧光定量RT-PCR方法进行诺如病毒检测.应用优化后的方法检测105份牡蛎样本,并用核苷酸序列测定法对阳性PCR产物进行验证.结果 甘氨酸缓冲液pH值为4.5,PEG沉淀浓度为16%时的诺如病毒富集提取效果最好,该方法的诺如病毒检出限为1.17×102个质粒拷贝.应用该方法对未知样本进行检测阳性率达14.29%,所得阳性PCR产物经核苷酸序列测序证实为诺如病毒.结论 本研究方法可以应用于牡蛎中的诺如病毒检测,南宁市海鲜市场上的部分牡蛎含有诺如病毒.%Aim To develop an assay for detection of norovirus in oysters. Methods The viral RNA was extracted and purified by using an optimized protocol of virus elution with glysine buffer and virus precipitation with polyethylene glycol (PEG). The RNA extracts were analyzed for norovirus using realtime RT-PCR. Positive PCR products were sequenced to further confirm the presence of virus. Results When the pH of glysine buffer was 4.5 and the concentration of PEG was 16%,higher levels of norovirus could be detected,with the detection limit of 1.17×102 copies. By this protocol,15 (14.29%) out of the 105 samples were tested positive. All the positive PCR products were confirmed as norovirus by sequence analysis. Conclusion The method adopted in this study is applicable for use in screening norovirus in oysters. The result shows that norovirus is present in oysters from aquatic markets in Nanning.8

  10. Aumento de consultas en atención primaria por infección respiratoria de vías altas y por fiebre coincidiendo con la gripe (H1N1 2009

    Directory of Open Access Journals (Sweden)

    Pablo Aldaz

    2011-01-01

    Full Text Available Fundamento: En verano de 2009 se registró en Navarra una onda de gripe A (H1N1 2009. Evaluar su repercusión en consultas de atención primaria con diagnóstico diferente al de gripe. Métodos: Estudiamos las consultas en atención primaria del Servicio Navarro de Salud desde el 21 de junio y al 21 de septiembre de 2009 con diagnósticos de gripe (Clasificación Internacional de Atención Primaria, código R80, síndrome febril (código A03, infección respiratoria aguda de vías altas (código R74 y bronquitis aguda (código R78, y las comparamos con las registradas en el mismo periodo en los tres años previos. Resultados: En verano de 2009 se notificaron 3417 casos de síndrome gripal (5,5 por 1.000 habitantes. Entre las semanas 27 y 31 se produjo un brote de gripe, con más de la mitad (87/160 de los frotis de pacientes con síndrome gripal positivos para el virus (H1N1 2009 sin detectarse otros tipos de virus gripal. Coincidiendo con la onda de síndromes gripales observamos aumentos de consultas por síndrome febril e infección respiratoria de vías altas. En comparación con la media de los tres años anteriores, en el verano del 2009 se produjo un incremento del 44! en consultas por síndrome febril (de 3,6 a 5,3 por 1000: p<0,001, del 6! en consultas por infección de vías altas (de 13,2 a 14,1 por 1000; p<0,001 y del 8! en consultas por bronquitis aguda (de 6,3 a 6,9 por 1000; p=0,003. Estos diagnósticos supusieron 3,2 consultas adicionales por 1.000 habitantes atribuibles a la gripe, es decir, un 58! de consultas adicionales. Conclusiones: La gripe se acompaña de aumento en el número de consultas por síndrome febril y por infección respiratoria de vías altas.

  11. Genotyping of Norovirus strains detected in outbreaks between April 2002 and March 2003 in Osaka City, Japan.

    Science.gov (United States)

    Seto, Yoshiyuki; Iritani, Nobuhiro; Kubo, Hideyuki; Kaida, Atsushi; Murakami, Tsukasa; Haruki, Kosuke; Nishio, Osamu; Ayata, Minoru; Ogura, Hisashi

    2005-01-01

    Noroviruses (NVs) are the major cause of food- and waterborne nonbacterial gastroenteritis in Japan. Between April 2002 and March 2003, a total of 111 fecal specimens from 40 outbreaks of acute nonbacterial gastroenteritis in Osaka City, Japan were subject to NV detection. Seventy-two samples (64.9%) from 31 outbreaks (77.5%) were NV positive by a real time reverse transcription (RT)-PCR assay. To further determine the genotype of individual NV strains, we sequenced the capsid N-terminal/shell (N/S) domain of some representative strains from each outbreak. The 51 NV strains detected in this study were segregated into 15 genotypes (6 in genogroup I and 9 in genogroup II), and GII/5 genotype NV was a dominant outbreak genotype.

  12. Group A rotavirus and norovirus display sharply distinct seasonal profiles in Belém, northern Brazil

    Directory of Open Access Journals (Sweden)

    Jones Anderson Monteiro Siqueira

    2013-08-01

    Full Text Available Several viruses have been associated with acute gastroenteritis (AGE, and group A rotavirus (RVA and nor-ovirus (NoV are the most prevalent. This study aimed to assess their prevalence among children hospitalised for diarrhoea during a three-year surveillance study. From May 2008-April 2011, overall positivity rates of 21.6% (628/2904 and 35.4% (171/483 were observed for RVA and NoV, respectively. The seasonality observed indicated distinct patterns when both viruses were compared. This finding may explain why hospitalisation for AGE remains constant throughout the year. Continuous AGE monitoring is needed to better assess the patterns of infection.

  13. Assessment of airborne bacteria and noroviruses in air emission from a new highly-advanced hospital wastewater treatment plant

    DEFF Research Database (Denmark)

    Uhrbrand, Katrine; Schultz, Anna Charlotte; Koivisto, A. J.

    2017-01-01

    wastewater treatment technologies. Air particle measurements and sampling of inhalable bacteria, endotoxin and noroviruses (NoVs) were performed indoor at the WWTP and outside at the WWTP ventilation air exhaust, downwind of the air exhaust, and upwind of the WWTP. No significant differences were seen....... In total, 35 different bacterial genera and 64 bacterial species were identified in the air samples. Significantly higher genus and species richness was found with an Andersen Cascade Impactor compared with filter-based sampling. No pathogenic bacteria were found in the exhaust air. Streptomyces...... to pose a health risk to surroundings. Hence, we assess the risk of airborne exposure to pathogenic bacteria and NoVs from the WWTP air emission to surroundings to be negligible. However, as a slightly higher NoV concentration was detected inside the WWTP, we cannot exclude the possibility that exposure...

  14. In Vitro Antiviral Activity of Clove and Ginger Aqueous Extracts against Feline Calicivirus, a Surrogate for Human Norovirus.

    Science.gov (United States)

    Aboubakr, Hamada A; Nauertz, Andrew; Luong, Nhungoc T; Agrawal, Shivani; El-Sohaimy, Sobhy A A; Youssef, Mohammed M; Goyal, Sagar M

    2016-06-01

    Foodborne viruses, particularly human norovirus, are a concern for public health, especially in fresh vegetables and other minimally processed foods that may not undergo sufficient decontamination. It is necessary to explore novel nonthermal techniques for preventing foodborne viral contamination. In this study, aqueous extracts of six raw food materials (flower buds of clove, fenugreek seeds, garlic and onion bulbs, ginger rhizomes, and jalapeño peppers) were tested for antiviral activity against feline calicivirus (FCV) as a surrogate for human norovirus. The antiviral assay was performed using dilutions of the extracts below the maximum nontoxic concentrations of the extracts to the host cells of FCV, Crandell-Reese feline kidney (CRFK) cells. No antiviral effect was seen when the host cells were pretreated with any of the extracts. However, pretreatment of FCV with nondiluted clove and ginger extracts inactivated 6.0 and 2.7 log of the initial titer of the virus, respectively. Also, significant dosedependent inactivation of FCV was seen when host cells were treated with clove and ginger extracts at the time of infection or postinfection at concentrations equal to or lower than the maximum nontoxic concentrations. By comprehensive two-dimensional gas chromatography-mass spectrometry analysis, eugenol (29.5%) and R-(-)-1,2-propanediol (10.7%) were identified as the major components of clove and ginger extracts, respectively. The antiviral effect of the pure eugenol itself was tested; it showed antiviral activity similar to that of clove extract, albeit at a lower level, which indicates that some other clove extract constituents, along with eugenol, are responsible for inactivation of FCV. These results showed that the aqueous extracts of clove and ginger hold promise for prevention of foodborne viral contamination.

  15. Effects of Abiotic and Biotic Stresses on the Internalization and Dissemination of Human Norovirus Surrogates in Growing Romaine Lettuce.

    Science.gov (United States)

    DiCaprio, Erin; Purgianto, Anastasia; Li, Jianrong

    2015-07-01

    Human norovirus (NoV) is the major causative agent of fresh-produce-related outbreaks of gastroenteritis; however, the ecology and persistence of human NoV in produce systems are poorly understood. In this study, the effects of abiotic and biotic stresses on the internalization and dissemination of two human NoV surrogates (murine norovirus 1 [MNV-1] and Tulane virus [TV]) in romaine lettuce were determined. To induce abiotic stress, romaine lettuce was grown under drought and flood conditions that mimic extreme weather events, followed by inoculation of soil with MNV-1 or TV. Independently, lettuce plants were infected with lettuce mosaic virus (LMV) to induce biotic stress, followed by inoculation with TV. Plants were grown for 14 days, and viral titers in harvested tissues were determined by plaque assays. It was found that drought stress significantly decreased the rates of both MNV-1 and TV internalization and dissemination. In contrast, neither flood stress nor biotic stress significantly impacted viral internalization or dissemination. Additionally, the rates of TV internalization and dissemination in soil-grown lettuce were significantly higher than those for MNV-1. Collectively, these results demonstrated that (i) human NoV surrogates can be internalized via roots and disseminated to shoots and leaves of romaine lettuce grown in soil, (ii) abiotic stress (drought) but not biotic stress (LMV infection) affects the rates of viral internalization and dissemination, and (iii) the type of virus affects the efficiency of internalization and dissemination. This study also highlights the need to develop effective measures to eliminate internalized viruses in fresh produce.

  16. In vivo comparison of two human norovirus surrogates for testing ethanol-based handrubs: the mouse chasing the cat!

    Directory of Open Access Journals (Sweden)

    Syed A Sattar

    Full Text Available Human noroviruses (HuNoV, a major cause of acute gastroenteritis worldwide, cannot be readily cultured in the lab. Therefore, a feline calicivirus (FCV is often used as its surrogate to, among other things, test alcohol-based handrubs (ABHR. The more recent laboratory culture of a mouse norovirus (MNV provides an alternative. While MNV is closer to HuNoV in several respects, to date, no comparative testing of FCV and MNV survival and inactivation on human hands has been performed. This study was designed to address the knowledge gap. The rates of loss in viability during drying on hands were -1.91 and -1.65% per minute for FCV and MNV, respectively. When the contaminated skin was exposed for 20 s to either a commercial ABHR with 62% (v/v ethanol or to 75% (v/v ethanol in water, FCV infectivity was reduced by 3.5 log₁₀ by the commercial ABHR while 75% ethanol did not show any noticeable improvement in activity as compared to the 20 s contact. An 80% (v/v aqueous solution of ethanol gave only a 1.75 log₁₀ reduction in MNV activity after 20 s. The results show significant differences in the ethanol susceptibility of FCV and MNV in contact times relevant to field use of ABHR and also that 62% ethanol was a more effective virucide than either 75% or 80% ethanol. These findings indicate the need for a review of the continuing use of FCV as a surrogate for HuNoV.

  17. Of gastro and the gold standard: evaluation and policy implications of norovirus test performance for outbreak detection

    Directory of Open Access Journals (Sweden)

    Fisman David N

    2009-03-01

    Full Text Available Abstract Background The norovirus group (NVG of caliciviruses are the etiological agents of most institutional outbreaks of gastroenteritis in North America and Europe. Identification of NVG is complicated by the non-culturable nature of this virus, and the absence of a diagnostic gold standard makes traditional evaluation of test characteristics problematic. Methods We evaluated 189 specimens derived from 440 acute gastroenteritis outbreaks investigated in Ontario in 2006–07. Parallel testing for NVG was performed with real-time reverse-transcriptase polymerase chain reaction (RT2-PCR, enzyme immunoassay (EIA and electron microscopy (EM. Test characteristics (sensitivity and specificity were estimated using latent class models and composite reference standard methods. The practical implications of test characteristics were evaluated using binomial probability models. Results Latent class modelling estimated sensitivities of RT2-PCR, EIA, and EM as 100%, 86%, and 17% respectively; specificities were 84%, 92%, and 100%; estimates obtained using a composite reference standard were similar. If all specimens contained norovirus, RT2-PCR or EIA would be associated with > 99.9% likelihood of at least one test being positive after three specimens tested. Testing of more than 5 true negative specimens with RT2-PCR would be associated with a greater than 50% likelihood of a false positive test. Conclusion Our findings support the characterization of EM as lacking sensitivity for NVG outbreaks. The high sensitivity of RT2-PCR and EIA permit identification of NVG outbreaks with testing of limited numbers of clinical specimens. Given risks of false positive test results, it is reasonable to limit the number of specimens tested when RT2-PCR or EIA are available.

  18. Ototoxicidad por medicamentos

    OpenAIRE

    Mercado M,Víctor; Burgos S,Rodolfo; Muñoz V,Claudio

    2007-01-01

    Se define ototoxicidad a las perturbaciones transitorias o definitivas de la función auditiva, vestibular, o de las dos a la vez, inducidas por sustancias de uso terapéutico¹. Son muchos los trabajos de investigación que se han dedicado ha este tema quedando aun dudas por resolver debido a las complejas consecuencias donde está envuelto el daño cocleovestibular. El propósito de esta revisión, es presentar las últimas teorías que tratan de explicar desde el punto de vista de la farmacociónétic...

  19. Electrocardiografo por computadora

    OpenAIRE

    Tinoco Hernandez, Rosanna; Paredes Bejarano, Margarita; Romero Chaglia, Norman; Yapur Auad, Miguel Eduardo

    2009-01-01

    El presente trabajo trata sobrees el diseño y la implementación de un graficador de señales cardiacas por computadora, para lo cual diseñamos un circuito electrónico capaz de recibir la senal analógica proveniente de la actividad electrica del corazón , amplificarla, y luego convertirla en una señal digital para ser procesada por software y finalmente ser graficada, siendo posible así observar la señal cardiaca en el monitor de un computador como un tren de pulsos. Cabe destacar que par...

  20. X-ray structure at 1.75 resolution of a norovirus 3C protease linked to an active site-directed peptide inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Jon [University of Southampton, England; Coates, Leighton [ORNL; Hussey, Robert [University of Southampton, England

    2010-01-01

    Noroviruses are recognized universally as the most important cause of human epidemic non-bacterial gastroenteritis. Viral replication requires a 3C cysteine protease that cleaves a 200kDa viral polyprotein into its constituent functional proteins. Here we describe the X-ray structure of the Southampton norovirus 3C protease (SV3CP) bound to an active site-directed peptide inhibitor (MAPI) which has been refined at 1.75 resolution, following initial MAD phasing with a selenomethionine derivative. The inhibitor, acetyl-Glu-Phe-Gln-Leu-Gln-X, based on a 3C protease cleavage recognition sequences in the 200kDa polyprotein substrate, reacts covalently through its propenylethylester group (X) with the active site nucleophile, Cys 139. The 3C protease-inhibitor structure permits, for the first time, the identification of substrate recognition and binding groups and provides important new information for the development of antiviral prophylactics.

  1. Diagnóstico clínico patológico de brotes de enfermedades en tilapia roja (oreochromis spp.)

    OpenAIRE

    Rey, A. L.; Iregui Castro, C. A.; Verján, N.

    2012-01-01

    Se diagnosticaron las distintas patologías en tilapia roja que fueron consultadas al servicio de diagnóstico del Laboratorio de Patología de la Facultad de medicina Veterinaria de la Universidad Nacional, describiendo y clasificando los tipos de alteraciones macro y microscópicas e intentando formular los primeros mapas epidemiológicos por región geográfica y para esta especie. (...)

  2. Norovirus and MS2 inactivation kinetics of UV-A and UV-B with and without TiO2.

    Science.gov (United States)

    Lee, Jung Eun; Ko, GwangPyo

    2013-10-01

    Germicidal ultraviolet, such as 254-nm UV-C, is a common method of disinfection of pathogenic enteric viruses. However, the disinfection efficacies of UV-A or -B in terms of inactivating waterborne viruses such as norovirus have not been characterized. We evaluated the inactivation kinetics of MS2 bacteriophage and murine norovirus (MNV), a surrogate of human norovirus (NoV), by UV-A and -B. In addition to UV disinfection, we further investigated whether the presence of TiO2 could enhance the virus inactivation kinetics of UV-A and -B. Both MS2 and MNV were highly resistant to UV-A. However, the addition of TiO2 enhanced the efficacy of UV-A for inactivating these viruses. UV-A dose of 1379 mJ/cm(2) resulted in a 4 log10 reduction. In comparison, UV-B alone effectively inactivated both MS2 and MNV, as evidenced by the 4 log10 reduction by 367 mJ/cm(2) of UV-B. The addition of TiO2 increased the inactivation of MS2; however, it did not significantly increase the efficacy of UV-B disinfection for inactivating MNV. When these treatments were applied to field water such as groundwater, the results were generally consistent with the laboratory findings. Our results clearly indicated that UV-B is useful for the disinfection of waterborne norovirus. However, MNV was quite resistant to UV-A, and UV-A effectively inactivated the tested viruses only when used in combination with TiO2.

  3. Review: norovirus prevalence in Belgian, Canadian and French fresh produce: a threat to human health?

    Science.gov (United States)

    Baert, L; Mattison, K; Loisy-Hamon, F; Harlow, J; Martyres, A; Lebeau, B; Stals, A; Van Coillie, E; Herman, L; Uyttendaele, M

    2011-12-15

    Foodborne viruses, especially noroviruses (NoV), are increasingly reported as the cause of foodborne outbreaks. NoV outbreaks have been reported linked to fresh soft red fruits and leafy greens. Belgium, Canada and France were the first countries to provide data about the prevalence of NoV on fresh produce. In total, 867 samples of leafy greens, 180 samples of fresh soft red fruits and 57 samples of other types of fresh produce (tomatoes, cucumber and fruit salads) were analyzed. Firstly, the NoV detection methodology, including virus and RNA extraction, real-time RT-PCR and quality controls were compared among the three countries. In addition, confirmation and genotyping of the NoV strains was attempted for a subset of NoV positive samples using conventional RT-PCR targeting an alternative region followed by sequencing. Analysis of the process control showed that 653, 179 and 18 samples of the leafy greens, soft red fruits and other fresh produce types were valid for analysis based on the recovery of the process control. NoV was detected by real-time RT-PCR in 28.2% (N=641), 33.3% (N=6) and 50% (N=6) of leafy greens tested in Canada, Belgium and France, respectively. Soft red fruits were found positive by real-time RT-PCR in 34.5% (N=29) and 6.7% (N=150) of the samples tested in Belgium and France, respectively. 55.5% (N=18) of the other fresh produce types, analyzed in Belgium, were found NoV positive by real-time RT-PCR. Conventional RT-PCR resulted in an amplicon of the expected size in 19.5% (52/266) of the NoV positive samples where this assay was attempted. Subsequent sequencing was only successful in 34.6% (18/52) of the suspected amplicons obtained by conventional RT-PCR. From this study, using the described methodology, NoV genomes were frequently detected in fresh produce however sequence confirmation was not successful for the majority of the samples tested. Infection or outbreaks were rarely or not known to be related to the NoV positive samples. With

  4. Escherichia coli, Salmonella spp., Virus dell'Epatite A e Norovirus in Molluschi Bivalvi nel 2011-12 in Sud Italia

    Directory of Open Access Journals (Sweden)

    Giovanna Fusco

    2013-03-01

    Full Text Available La legislazione europea ha fissato limiti microbiologici, chimici e biotossicologici per i molluschi ma non ha dato indicazioni sulla contaminazione da virus a trasmissione alimentare. In questo studio sono riportati i risultati sulla contaminazione da Salmonella spp., Escherichia coli (E. coli, Virus dell'Epatite A (HAV e Norovirus (NoV di campioni di molluschi raccolti, nel biennio 2011-2012, in Sud Italia. Tutte le matrici analizzate di Mytilus galloprovincialis e di Solen marginatus sono risultate negative all'HAV, il 6,8% positiva a Norovirus GI (NoVGI e l'11,9% positiva a Norovirus GII (NoVGII. Inoltre esse sono risultate negative alla contaminazione da Salmonella spp. mentre il 27% è risultata positiva a E. coli. I dati ottenuti, inoltre, hanno dimostrato l'assenza di correlazione tra la contaminazione batterica dei Molluschi Bivalvi eduli testati e quella virale. Si suggerisce alle Autorità Competenti la valutazione urgente di misure normative aggiuntive al fine di garantire la sicurezza al consumatore.

  5. Prevención y control de la infección ante sujetos sospechosos de infección por el nuevo coronavirus MERS-CoV en Unidades militares

    Directory of Open Access Journals (Sweden)

    MªE. Mayo Montero

    2015-09-01

    Full Text Available Los primeros casos del nuevo coronavirus MERS-CoV surgieron en Arabia Saudí en el año 2012. Hasta la fecha el virus se ha extendido a países vecinos, notificándose casos importados en Europa, América del Norte, África y Asia. En mayo de 2015 se declara a la OMS el primer caso confirmado por laboratorio de un brote en Corea del Sur, donde se ha producido hasta transmisión cuaternaria. El agente se transmite por vía aérea, por contacto directo con secreciones infectadas y por fómites, presenta una letalidad en torno al 37%. Por lo que en el manejo de pacientes se adoptarán precauciones estándar, de contacto y de transmisión aérea cuando se apliquen técnicas que generen aerosoles. Debido a la gravedad de la enfermedad y al desconocimiento de los mecanismos de transmisión, resulta prioritario establecer en las unidades militares donde se sospeche la aparición de un caso las medidas de prevención y control de la infección para: detectar rápida y precozmente un caso sospechoso, proteger al personal sanitario, a otros pacientes y al resto del personal, así como implementar las medidas de aislamiento apropiadas.

  6. Osteomielitis por salmonella

    Directory of Open Access Journals (Sweden)

    Alicia Velázquez Pérez

    2014-08-01

    Full Text Available Se presenta el caso de una paciente femenina de color blanco y dos años de edad, con diagnóstico prenatal de sicklemia, que desde edades tempranas tiene problemas de la enfermedad. Ingresó en esta ocasión por una de las complicaciones infecciosas que ocasiona este padecimiento, una osteomielitis del húmero izquierdo, aislándose el germen en el hemocultivo realizado, una salmonella. Necesitó de tratamiento enérgico y prolongado; se obtuvo un resultado satisfactorio en la evolución de la enfermedad y se sigue sistemáticamente por consulta externa en la actualidad

  7. causada por Fusarium moniliforme

    Directory of Open Access Journals (Sweden)

    Mariano Mendoza Elos

    2006-01-01

    Full Text Available El objetivo de éste trabajo fue determinar la resistencia horizontal de 134 líneas S1 de maíz al hongo Fusarium moniliforme. La enfermedad fue inducida mediante inoculación en la etapa de floración masculina bajo condiciones de campo utilizando la técnica del palillo. Las líneas se evaluaron en México en 2002. La estimación de la enfermedad se hizo en dos ocasiones con una separación de 20 días. Las evaluaciones mostraron que las líneas Roque-801, 804, 1103 y 1405 fueron resistentes en la primera evaluación. Las tasas de incremento de la enfermedad variaron de 0,01 a 0,229 por unidad por día. Las líneas mostraron bajos niveles de enfermedad de 0 a 1 % en la primera evaluación. En la segunda evaluación, los niveles de enfermedad variaron de 49 a 100 %. En un programa de mejoramiento genético estas líneas pueden ser utilizadas para mejorar la resistencia horizontal del maíz a la pudrición del tallo causada por Fusarium moniliforme

  8. La lucha por Guayaquil

    Directory of Open Access Journals (Sweden)

    Felipe Burbano de Lara

    2009-01-01

    Full Text Available En el contexto del referendo constitucional del 2008 en Ecuador, este texto analiza la disputa entre Rafael Correa, presidente del Gobierno ecuatoriano y principal líder de Alianza País, y el alcalde la ciudad más grande del país, Jaime Nebot. Disputa que es examinada a partir de tres ejes: la lucha contra el neoliberalismo, la construcción de un proyecto estatal nacional y la búsqueda por una por una hegemonía política de Alianza País. Se profundiza en las nociones de autonomía y globalización que sirvieron de eje al discurso del alcalde, frente al modelo de autonomía propuesto por el Gobierno.In the context of Ecuador's 2008 Constitutional Referendum, this text analyses the dispute between Rafael Correa –the President of the Ecuadorian government and the figurehead of Alianza País– and the mayor of the largest city in the country, Jaime Nebot. The argument will be developed along three fronts: the battle against neoliberalism, the construction of a national state project, and the search for the political hegemony of Alianza País. The article examines the concepts of autonomy and globalization that were central to Nebot's discourse and contrasts them with the autonomous model put forward by the government.

  9. Inactivation efficiency and mechanism of UV-TiO2 photocatalysis against murine norovirus using a solidified agar matrix.

    Science.gov (United States)

    Park, Daseul; Shahbaz, Hafiz Muhammad; Kim, Sun-Hyoung; Lee, Mijin; Lee, Wooseong; Oh, Jong-Won; Lee, Dong-Un; Park, Jiyong

    2016-12-05

    Human norovirus (HuNoV) is the primary cause of viral gastroenteritis worldwide. Fresh blueberries are among high risk foods associated with norovirus related outbreaks. Therefore, it is important to assess intervention strategies to reduce the risk of foodborne illness. The disinfection efficiency of decontamination methods is difficult to evaluate for fruits and vegetables due to an inconsistent degree of contamination and irregular surface characteristics. The inactivation efficiency and mechanism of murine norovirus 1 (MNV-1, a surrogate for HuNoV) was studied on an experimentally prepared solidified agar matrix (SAM) to simulate blueberries using different wavelengths (A, B, C) of UV light both with and without TiO2 photocatalysis (TP). MNV-1 was inoculated on exterior and interior of SAM and inactivation efficiencies of different treatments were investigated using a number of assays. Initial inoculum levels of MNV-1 on the SAM surface and interior were 5.2logPFU/mL. UVC with TiO2 (UVC-TP) achieved the highest level of viral reduction for both externally inoculated and internalized MNV-1. Externally inoculated MNV-1 was reduced to non-detectable levels after UVC-TP treatment for 5min while there was still a 0.9 log viral titer after UVC alone. For internalized MNV-1, 3.2 log and 2.7 log reductions were obtained with UVC-TP and UVC alone treatments for 10min, respectively. The Weibull model was applied to describe the inactivation behavior of MNV-1, and the model showed a good fit to the data. An excellent correlation between the steady-state concentration of OH radicals ([OH]ss) and viral inactivation was quantified using a para-chlorobenzoic acid (pCBA) probe compound, suggesting that OH radicals produced in the UV-TP reaction were the major species for MNV-1 inactivation. Transmission electron microscopy images showed that the structure of viral particles was completely disrupted with UVC-TP and UVC alone. SDS-PAGE analysis showed that the major capsid

  10. Reprogramación celular de embriones de Anthurium andraeanum por fitohormonas para micropropagación masiva

    Directory of Open Access Journals (Sweden)

    Julieta Mireles-Ordaz

    2015-01-01

    Full Text Available El género Anthurium incluye alrededor de 800 especies, las cuales son originarias de diversos países tropicales y subtropicales de América. Numerosos cultivos de estas especies de Anthurium son crecidos y comercializados debido a su gran popularidad como plantas ornamentales alrededor de todo el mundo, de las cuales la más popular es Anthurium andreanum. La reproducción sexual de estas plantas en invernaderos es difícil y toma mucho tiempo, lo cual representa una desventaja para su producción masiva y comercialización. La micropropagación in vitro ha emergido como una opción para sobrellevar dicha desventaja, hasta la fecha se han logrado avances parcialmente exitosos en la micropropagación en especies de Anthurium usando varios tejidos como explantes iniciales, incluyendo hojas, pecíolo, espádice, espata, brote lateral, meristemo apical y embriones somáticos, estos últimos previamente inducidos a partir de tejido diferenciado. Sin embargo, hasta ahora no hay reportes del uso de embriones cigóticos como tejido madre para la propagación masiva de estas plantas. En el presente estudio reportamos la formación de callos organogénicos a partir de embriones cigóticos inmaduros crecidos en medio MS suplementado con la combinación de 2 mg/l de ácido 2,4-diclorofenoxiacético (2,4-D y 0.5 mg/l de 6-benzilamino-purina (BAP. Los resultados obtenidos demuestran que los embriones en proceso de desarrollo son altamente eficientes como explantes de origen para inducir la formación de tejido calloso de una manera rápida y fácil, dando en promedio 9 brotes por callo y logrando una taza de sobrevivencia de las plantas del 90% en la fase de aclimatación.

  11. EFSA BIOHAZ Panel (EFSA Panel on Biological Hazards), 2014. Scientific Opinion on the risk posed by pathogens in food of non-animal origin. Part 2 (Salmonella and Norovirus in berries)

    DEFF Research Database (Denmark)

    Hald, Tine; Baggesen, Dorte Lau

    Berries are a perishable food which can be consumed as fresh or minimally-processed as well as a frozen ingredient added to many foods. Strawberries, raspberries, blackberries and blueberries are the most commonly consumed in the EU. Risk factors for berry contamination by Salmonella and Norovirus...... base for establishing a Process Hygiene and Food Safety Criteria for Norovirus in berries. Collection of appropriate data and subsequent risk-based development of microbiological criteria to support improved control of Norovirus in frozen raspberries and strawberries should be considered as a priority....... were considered in the context of the whole food chain. Available estimates of the prevalence of these pathogens in berries were evaluated together with mitigation options relating to prevention of contamination and the relevance of microbiological criteria. It was concluded that each farm environment...

  12. Por mil devaluados pesos

    Directory of Open Access Journals (Sweden)

    Annie Rodríguez Collázos

    2013-03-01

    Full Text Available El estudio de lo popular y lo urbano hasta ahora se ha centrado en el comportamiento y en algunas relaciones de los habitantes con su entorno. “Por mil devaluados pesos. Publicidad popular y urbana”, pretende explorar las formas de publicidad, dispersas en diferentes espacios populares y urbanos en Bogotá, identificando esquemas y formas características de sus propios códigos comunicativos; se centran en un objeto de estudio consistente en las estrategias publicitarias y los códigos comunicativos en los mensajes publicitarios populares en las subculturas de San Victorino, 7 de Agosto y Sanandresito de San José.

  13. Aprendizaje significativo por competencias

    OpenAIRE

    Acevedo Tovar, Luz Marina; Universidad Nacional Mayor de San Marcos

    2014-01-01

    Los cambios que desde hace un tiempo se han venido produciendo en educación, han dado lugar a la aparición de nuevos conceptos o a la modificación del significado de algunos térmi¬nos. Dos de estos conceptos, son los de aprendizaje significativo y competencias ¿Qué es realmente aprendizaje significativo?; ¿existe una oposición entre aprendizaje signifi¬cativo y aprendizaje repetitivo?- ¿el aprendizaje significativo es posible sólo por competen¬cias?.- Intentaré responder a estos interrogantes...

  14. Onicomicosis por hongos fuliginosos

    OpenAIRE

    Ingrid Salas-Campos; Norma T Gross-Martinez; Pedro J Carrillo-Dover

    2009-01-01

    Justificación y objetivo: Las infecciones de las uñas producidas por hongos son un problema de frecuente consulta dermatológica. Los dermatofitos son la mayor causa de estas infecciones, siendo Trichophyton rubrum el agente etiológico más importante. Sin embargo, los hongos no dermatofitos, tanto hialinos como fuliginosos, pueden ser también responsables de estos cuadros clínicos. Debido a que estos hongos tienden a ser resistentes a los antimicóticos comúnmente usados para tratar las onicomi...

  15. Inactivation of murine Norovirus-1, coliphage φX174 and Bacteroides fragilis phage B40-8 on surfaces and fresh cut iceberg lettuce by hydrogen peroxide and UV light

    OpenAIRE

    2011-01-01

    In this study, the inactivating properties of liquid hydrogen peroxide (L-H2O2), vaporized hydrogen peroxide (V-H2O2), UV light, and a combination of V-H2O2 and UV light were tested on murine norovirus 1 (MNV-1) and bacteriophages (φX174 and B40-8) as models for human noroviruses. Disinfection of surfaces was examined on stainless steel discs based on European Standard EN 13697 (2001). For fresh-produce decontamination, a mixture of the viruses was inoculated onto shredded iceberg lettuce and...

  16. Caracterización epidemiológica, clínica y microbiológica del brote de diarrea asociado a Clostridium difficile, ocurrido en el Hospital San Juan de Dios, 2008-2009 Epidemiologic, clinical, and microbiologic description of an outbreak of Clostridium difficile associated diarrhea in Costa Rica

    OpenAIRE

    Manuel Antonio Villalobos-Zúñiga; Ricardo Boza-Cordero

    2012-01-01

    Antecedentes: la enfermedad diarreica asociada a Clostridium difficile (EDACD) es la causa más importante de diarrea nosocomial en el mundo. En Costa Rica, se presentó recientemente un brote de EDACD en el Hospital San Juan de Dios de San José, hospital de tercer nivel con 700 camas. En el estudio se analizan las características epidemiológicas, clínicas y microbiológicas de los pacientes con EDACD atendidos entre noviembre de 2008 y junio de 2009. Pacientes y métodos: se definió como caso de...

  17. Clinical characteristics and genetic diversity of noroviruses in adults with acute gastroenteritis in Beijing, China in 2008-2009.

    Science.gov (United States)

    Tian, Geng; Jin, Miao; Li, Huiying; Li, Quanrui; Wang, Jing; Duan, Zhao-jun

    2014-07-01

    Norovirus (NoV) infections that cause acute gastroenteritis are commonly observed during colder months. This study was conducted to investigate the clinical features and molecular epidemiology of NoVs in adult outpatients with acute gastroenteritis in Beijing, China from August 2008 to July 2009. Five hundred nineteen patients were enrolled, their stool specimens were collected, and 136 (26.2%) were positive for NoV. The elderly were found to be more susceptible to NoVs than other age groups. The greatest number of gastroenteritis cases associated with occurred in October. Six GI and eleven GII NoV genotypes were isolated; among these, the GII.4 genotype was most prevalent (70/140 and 50% were the 2006b variant). The elderly were more susceptible to the GII.4 genotype than to other genotypes. Greater numbers of neutrophils in the peripheral blood were observed in the NoV infected group than in uninfected control group. However, the levels of neutrophils and leukocytes in the non-GII.4 patients infected with NoV were higher than those of the GII.4-infected patients. The data highlight the role of NoV as a primary agent responsible for gastroenteritis in adults in Beijing, China.

  18. Identifying Carbohydrate Ligands of a Norovirus P Particle using a Catch and Release Electrospray Ionization Mass Spectrometry Assay

    Science.gov (United States)

    Han, Ling; Kitova, Elena N.; Tan, Ming; Jiang, Xi; Klassen, John S.

    2014-01-01

    Noroviruses (NoVs), the major cause of epidemic acute gastroenteritis, recognize human histo-blood group antigens (HBGAs), which are present as free oligosaccharides in bodily fluid or glycolipids and glycoproteins on the surfaces of cells. The subviral P particle formed by the protruding (P) domain of the NoV capsid protein serves as a useful model for the study NoV-HBGA interactions. Here, we demonstrate the application of a catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS) assay for screening carbohydrate libraries against the P particle to rapidly identify NoV ligands and potential inhibitors. Carbohydrate libraries of 50 and 146 compounds, which included 18 and 24 analogs of HBGA receptors, respectively, were screened against the P particle of VA387, a member of the predominant GII.4 NoVs. Deprotonated ions corresponding to the P particle bound to carbohydrates were isolated and subjected to collision-induced dissociation to release the ligands in their deprotonated forms. The released ligands were identified by ion mobility separation followed by mass analysis. All 13 and 16 HBGA ligands with intrinsic affinities >500 M-1 were identified in the 50 and the 146 compound libraries, respectively. Furthermore, screening revealed interactions with a series of oligosaccharides with structures found in the cell wall of mycobacteria and human milk. The affinities of these newly discovered ligands are comparable to those of the HBGA receptors, as estimated from the relative abundance of released ligand ions.

  19. Type I Interferon Receptor Deficiency in Dendritic Cells Facilitates Systemic Murine Norovirus Persistence Despite Enhanced Adaptive Immunity.

    Directory of Open Access Journals (Sweden)

    Timothy J Nice

    2016-06-01

    Full Text Available In order for a virus to persist, there must be a balance between viral replication and immune clearance. It is commonly believed that adaptive immunity drives clearance of viral infections and, thus, dysfunction or viral evasion of adaptive immunity is required for a virus to persist. Type I interferons (IFNs play pleiotropic roles in the antiviral response, including through innate control of viral replication. Murine norovirus (MNoV replicates in dendritic cells (DCs and type I IFN signaling in DCs is important for early control of MNoV replication. We show here that the non-persistent MNoV strain CW3 persists systemically when CD11c positive DCs are unable to respond to type I IFN. Persistence in this setting is associated with increased early viral titers, maintenance of DC numbers, increased expression of DC activation markers and an increase in CD8 T cell and antibody responses. Furthermore, CD8 T cell function is maintained during the persistent phase of infection and adaptive immune cells from persistently infected mice are functional when transferred to Rag1-/- recipients. Finally, increased early replication and persistence are also observed in mixed bone marrow chimeras where only half of the CD11c positive DCs are unable to respond to type I IFN. These findings demonstrate that increased early viral replication due to a cell-intrinsic innate immune deficiency is sufficient for persistence and a functional adaptive immune response is not sufficient for viral clearance.

  20. Increased and prolonged human norovirus infection in RAG2/IL2RG deficient gnotobiotic pigs with severe combined immunodeficiency

    Science.gov (United States)

    Lei, Shaohua; Ryu, Junghyun; Wen, Ke; Twitchell, Erica; Bui, Tammy; Ramesh, Ashwin; Weiss, Mariah; Li, Guohua; Samuel, Helen; Clark-Deener, Sherrie; Jiang, Xi; Lee, Kiho; Yuan, Lijuan

    2016-01-01

    Application of genetically engineered (GE) large animals carrying multi-allelic modifications has been hampered by low efficiency in production and extended gestation period compared to rodents. Here, we rapidly generated RAG2/IL2RG double knockout pigs using direct injection of CRISPR/Cas9 system into developing embryos. RAG2/IL2RG deficient pigs were immunodeficient, characterized by depletion of lymphocytes and either absence of or structurally abnormal immune organs. Pigs were maintained in gnotobiotic facility and evaluated for human norovirus (HuNoV) infection. HuNoV shedding lasted for 16 days in wild type pigs, compared to 27 days (until the end of trials) in RAG2/IL2RG deficient pigs. Additionally, higher HuNoV titers were detected in intestinal tissues and contents and in blood, indicating increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs and the importance of lymphocytes in HuNoV clearance. These results suggest that GE immunodeficient gnotobiotic pigs serve as a novel model for biomedical research and will facilitate HuNoV studies. PMID:27118081

  1. Effects of a Variety of Food Extracts and Juices on the Specific Binding Ability of Norovirus GII.4 P Particles

    Science.gov (United States)

    LI, DAN; BAERT, LEEN; XIA, MING; ZHONG, WEIMING; JIANG, XI; UYTTENDAELE, MIEKE

    2014-01-01

    The effects of 13 food extracts and juices, including shellfish, fruits, and vegetables, on the binding ability of human norovirus (NoV) were examined, using P particles of human NoV GII.4 as a research surrogate. The enhancements (positive values) or reductions (negative values) of NoV P particle detection (changes in optical density at 450 nm) in the presence of different food extracts and juices as compared with P particles diluted in phosphate-buffered saline were tested by saliva-binding, enzyme-linked immunosorbent assay in triplicate. In the presence of different food extracts and juices at different concentrations, an increase or decrease of the receptor-binding ability of the NoV P particles was observed. Due to a higher specific binding and thus a higher accumulation of the viral particles, oysters may be contaminated with human NoV more often than other shellfish species (mussel, hard clams, and razor clams). Cranberry and pomegranate juices were shown to reduce the specific binding ability of human NoV P particles. No such binding inhibition effects were observed for the other tested extracts of fresh produce (strawberry, blackberry, blueberry, cherry tomato, spinach, romaine lettuce) or, notably, for raspberry, which has been associated with human NoV outbreaks. PMID:22980024

  2. Radiation sensitivity of poliovirus, a model for norovirus, inoculated in oyster ( Crassostrea gigas) and culture broth under different conditions

    Science.gov (United States)

    Jung, Pil-Mun; Park, Jae Seok; Park, Jin-Gyu; Park, Jae-Nam; Han, In-Jun; Song, Beom-Seok; Choi, Jong-il; Kim, Jae-Hun; Byun, Myung-Woo; Baek, Min; Chung, Young-Jin; Lee, Ju-Woon

    2009-07-01

    Poliovirus is a recognized surrogate for norovirus, pathogen in water and food, due to the structural and genetic similarity. Although radiation sensitivity of poliovirus in water or media had been reported, there has been no research in food model such as shellfish. In this study, oyster ( Crassostrea gigas) was incubated in artificial seawater contaminated with poliovirus, and thus radiation sensitivity of poliovirus was determined in inoculated oyster. The effects of ionizing radiation on the sensitivity of poliovirus were also evaluated under different conditions such as pH (4-7) and salt concentration (1-15%) in culture broth, and temperature during irradiation. The D10 value of poliovirus in PBS buffer, virus culture broth and oyster was determined to 0.46, 2.84 and 2.94 kGy, respectively. The initial plaque forming unit (PFU) of poliovirus in culture broth was slightly decreased as the decrease of pH and the increase of salt concentration, but radiation sensitivity was not affected by pH and salt contents. However, radiation resistance of poliovirus was increased at frozen state. These results provide the basic information for the inactivation of pathogenic virus in foods by using irradiation.

  3. Rotavirus Recombinant VP6 Nanotubes Act as an Immunomodulator and Delivery Vehicle for Norovirus Virus-Like Particles

    Science.gov (United States)

    Lappalainen, Suvi; Vesikari, Timo

    2016-01-01

    We have recently shown that tubular form of rotavirus (RV) recombinant VP6 protein has an in vivo adjuvant effect on the immunogenicity of norovirus (NoV) virus-like particle (VLP) vaccine candidate. In here, we investigated in vitro effect of VP6 on antigen presenting cell (APC) activation and maturation and whether VP6 facilitates NoV VLP uptake by these APCs. Mouse macrophage cell line RAW 264.7 and dendritic cell line JAWSII were used as model APCs. Internalization of VP6, cell surface expression of CD40, CD80, CD86, and major histocompatibility class II molecules, and cytokine and chemokine production were analyzed. VP6 nanotubes were efficiently internalized by APCs. VP6 upregulated the expression of cell surface activation and maturation molecules and induced secretion of several proinflammatory cytokines and chemokines. The mechanism of VP6 action was shown to be partially dependent on lipid raft-mediated endocytic pathway as shown by methyl-β-cyclodextrin inhibition on tumor necrosis factor α secretion. These findings add to the understanding of mechanism by which VP6 exerts its immunostimulatory and immunomodulatory actions and further support its use as a part of nonlive RV-NoV combination vaccine. PMID:27689099

  4. Radiation sensitivity of poliovirus, a model for norovirus, inoculated in oyster (Crassostrea gigas) and culture broth under different conditions

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Pil-Mun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Park, Jae Seok [Korea Food and Drug Administration, Seoul 122-704 (Korea, Republic of); Park, Jin-Gyu; Park, Jae-Nam; Han, In-Jun; Song, Beom-Seok; Choi, Jong-il; Kim, Jae-Hun; Byun, Myung-Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Baek, Min [Atomic Energy Policy Division, Ministry of Education, Science and Technology, Gwacheon 427-715 (Korea, Republic of); Chung, Young-Jin [Department of Food and Nutrition, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2009-07-15

    Poliovirus is a recognized surrogate for norovirus, pathogen in water and food, due to the structural and genetic similarity. Although radiation sensitivity of poliovirus in water or media had been reported, there has been no research in food model such as shellfish. In this study, oyster (Crassostrea gigas) was incubated in artificial seawater contaminated with poliovirus, and thus radiation sensitivity of poliovirus was determined in inoculated oyster. The effects of ionizing radiation on the sensitivity of poliovirus were also evaluated under different conditions such as pH (4-7) and salt concentration (1-15%) in culture broth, and temperature during irradiation. The D{sub 10} value of poliovirus in PBS buffer, virus culture broth and oyster was determined to 0.46, 2.84 and 2.94 kGy, respectively. The initial plaque forming unit (PFU) of poliovirus in culture broth was slightly decreased as the decrease of pH and the increase of salt concentration, but radiation sensitivity was not affected by pH and salt contents. However, radiation resistance of poliovirus was increased at frozen state. These results provide the basic information for the inactivation of pathogenic virus in foods by using irradiation.

  5. Increased and prolonged human norovirus infection in RAG2/IL2RG deficient gnotobiotic pigs with severe combined immunodeficiency.

    Science.gov (United States)

    Lei, Shaohua; Ryu, Junghyun; Wen, Ke; Twitchell, Erica; Bui, Tammy; Ramesh, Ashwin; Weiss, Mariah; Li, Guohua; Samuel, Helen; Clark-Deener, Sherrie; Jiang, Xi; Lee, Kiho; Yuan, Lijuan

    2016-04-27

    Application of genetically engineered (GE) large animals carrying multi-allelic modifications has been hampered by low efficiency in production and extended gestation period compared to rodents. Here, we rapidly generated RAG2/IL2RG double knockout pigs using direct injection of CRISPR/Cas9 system into developing embryos. RAG2/IL2RG deficient pigs were immunodeficient, characterized by depletion of lymphocytes and either absence of or structurally abnormal immune organs. Pigs were maintained in gnotobiotic facility and evaluated for human norovirus (HuNoV) infection. HuNoV shedding lasted for 16 days in wild type pigs, compared to 27 days (until the end of trials) in RAG2/IL2RG deficient pigs. Additionally, higher HuNoV titers were detected in intestinal tissues and contents and in blood, indicating increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs and the importance of lymphocytes in HuNoV clearance. These results suggest that GE immunodeficient gnotobiotic pigs serve as a novel model for biomedical research and will facilitate HuNoV studies.

  6. Vomiting Larry: a simulated vomiting system for assessing environmental contamination from projectile vomiting related to norovirus infection.

    Science.gov (United States)

    Makison Booth, Catherine

    2014-09-01

    Infectious diseases such as norovirus can induce emesis (vomiting), which can be of a projectile nature. Although studies have been carried out on transmission, prevalence and decontamination of such micro-organisms within various environments, little is known about the extent to which the surrounding environment is contaminated when an individual vomits. This is an important consideration for infection control purposes. The aim of this study was to develop a simulated vomiting system (Vomiting Larry) to be used for assessing the extent to which projected fluid can contaminate the environment. Vomiting Larry was set up within a Controlled Atmosphere Chamber (CAC) facility at the Health and Safety Laboratory (HSL). Simulated vomiting was undertaken using water as a vomitus substitute containing a fluorescent marker enabling small splashes, ordinarily missed, to be visualised using UV lighting. Experiments revealed that splashes and droplets produced during an episode of projectile vomiting can travel great distances (>3 m forward spread and 2.6 m lateral spread). The research highlighted that small droplets can be hard to see and therefore cleaning all contaminated surfaces is difficult to achieve. Evidence from this study suggests that areas of at least 7.8 m(2) should be decontaminated following an episode of projectile vomiting.

  7. Sepsis por shigella flexneri

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    César Cabrera C

    2005-04-01

    Full Text Available Se presenta un caso raro de sepsis por Shigella flexneri en una paciente de 45 años de edad quien estando hospitalizada para el estudio de un tumor cerebral, requirió el uso de manitol y dosis altas de corticoides; luego de ello presenta deposiciones líquidas con moco y sangre, desarrolla síndrome de respuesta inflamatoria sistémica, luego se aísla Shigella flexneri en el hemocultivo; recibió tratamiento antibiótico con ciprofloxacina. Se describen las características del caso y se comenta de acuerdo con la revisión de literatura.

  8. Pasos por la salud

    OpenAIRE

    Fierro Rojas, Carlos

    2013-01-01

    Pasos por la Salud surge como un proyecto (mismo que derivara una estrategia de atención) que establece el Departamento de Educación Física Valle de México, para fortalecer la aplicación del programa de Educación Física en Educación Básica, fomentará la práctica del ejercicio físico hacia la promoción de la salud, brindará a los alumnos elementos teóricos y bases metodológicas que le ayuden a comprender los beneficios de salud que producen la práctica del ejercicio, concientizar al alumno de ...

  9. Research on Relationship between Norovirus Outbreak and HBGAs Receptor%诺如病毒爆发与HBGAs受体关系的研究

    Institute of Scientific and Technical Information of China (English)

    唐亚丽; 陈茂余; 王立华; 杨玉芳; 戴迎春

    2013-01-01

    目的:研究诺如病毒爆发与HBGAs受体的关系.方法:选择2010年1月-2011年12月两年期间诺如病毒爆发的患者60例,作为实验组,同时,随机选择同期健康志愿者60例,作为对照组.收集患者和志愿者唾液,采用凝集抑制实验法检测唾液中HBGAS血型物质;用EIA法检测NoV-VLP与HBGAs的结合特性;比较不同型别诺如病毒爆发在实验组和对照组中HBGAs分布差异.结果:在感染诺如病毒的患者中,并无患者是唾液非分泌型,提示非分泌型HBGAs受体不与G Ⅱ 24型诺如病毒毒株结合与OD450值测定结果一致.其中检出分泌型中A型1例(1.67%),B型48例(80.00%),O型3例(5.00%),AB型2例(13.33%),60例患者的检测结果与其本身的血型相一致.无论是分泌型还是非分泌型的分布比例,两组存在明显的差异(P<0.05),具有统计学意义.结论:B型患者为诺如病毒感染的高度敏感人群,提示在我国人群的感染类型多以分泌型B型人群为主.%Objective: To investigate the relationship between Norovirus and HBGAs (Histo Blood Group Antigens) receptor. Methods: A total of 60 cases, infected by norovirus between January 2010 and December 2011, were chosen as experimental group, at the same time, 60 from healthy volunteers were randomly selected as control group. The saliva of the patients and volunteers were collected and HBGAS blood group substances in the saliva were detected by agglutination inhibition assay method, the characteristics of combination of NoV-VLP and HBGAs, by EIA method. HBGAs distribution with different types of norovirus erupt were compared between the experimental group and control group. Results: Among the patients infected by norovirus, there were no patients whose saliva was non-secretory type, suggesting that non-secreted HBGAs receptor didn't combine with GⅡ 24 strains of norovirus, which is consistent with the OD450 value determination results: In secreted type, 1 case of type A (1

  10. Onicomicosis por hongos fuliginosos

    Directory of Open Access Journals (Sweden)

    Ingrid Salas-Campos

    2009-12-01

    Full Text Available Justificación y objetivo: Las infecciones de las uñas producidas por hongos son un problema de frecuente consulta dermatológica. Los dermatofitos son la mayor causa de estas infecciones, siendo Trichophyton rubrum el agente etiológico más importante. Sin embargo, los hongos no dermatofitos, tanto hialinos como fuliginosos, pueden ser también responsables de estos cuadros clínicos. Debido a que estos hongos tienden a ser resistentes a los antimicóticos comúnmente usados para tratar las onicomicosis, es que se hace indispensable que el clínico se asegure por medio de un examen de laboratorio de la etiología de la infección. Métodos: Se estudiaron tres casos de pacientes con lesiones en uñas, que acudieron al laboratorio de Micología Médica, Facultad de Microbiología, Universidad de Costa Rica. Se realizaron los análisis de rutina para aislamiento e identificación de hongos patógenos. Resultados: En los tres casos estudiados se observó al examen directo micelio fuliginoso. En uno de los casos se aisló e identificó Scytalidium dimidiatum, hongo que presenta resistencia a los antifúngicos utilizados para tratar onicomicosis. Conclusión. El reporte de hongos diferentes a los dermatofitos como agentes etiológicos de onicomicosis es importante para que el médico pueda elegir el tratamiento más recomendado para este tipo de infección.

  11. Motivado por cirujanos

    Directory of Open Access Journals (Sweden)

    Carlos Salazar-Vargas

    2010-12-01

    Full Text Available Comenzaba la década de los 60 y nuestro grupo nerviosamente iniciaba lecciones en los hospitales de San José. En aquellos años, el estudiante de medicina empezaba su contacto con pacientes, por lo menos 1 ó 2 años después de iniciada la carrera. El estudio del ser humano normal que ya habíamos concluido, continuaba con el del enfermo, y más adelante aprenderíamos el tratamiento. La enfermedad descrita en el libro, de pronto se convertía en un enfermo, y es a este quien hoy veíamos, cohibido pero inquisidor, en la cama de un hospital. Los profesores nos enseñaban a interrogar y a examinar a los pacientes, y cada gesto suyo, cada pregunta, cada maniobra, eran celosamente guardados en la memoria de los educandos. Con claridad percibíamos, aun a temprana edad, las diferencias entre los especialistas, y casi de manera involuntaria, cada quien iba tomando partido y escogía su futuro camino. Fue durante esos tempranos años, cuando mi vida se cruzó con la de 7 maravillosas personas y excelentes cirujanos, que marcaron para siempre mi destino y, sin quererlo ellos, me hicieron inclinarme por la cirugía. Dos eran serios y profundamente académicos: el Dr. Manuel Aguilar Bonilla y el Dr. Vesalio Guzmán Calleja; 3, decididos, incansables y muy hábiles: el Dr. Longino Soto Pacheco, el Dr. Claudio Orlich Carranza y el Dr. Carlos Prada Díaz, y 2, abordables, prácticos, joviales y amistosos: el Dr. Fernando Valverde Soley y el Dr. Randall Ferris Iglesias….

  12. Scientific Opinion on the risk posed by pathogens in food of non-animal origin. Part 2 (Salmonella and Norovirus in leafy greens eaten raw as salads

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Biological Hazards (BIOHAZ

    2014-03-01

    Full Text Available Leafy greens eaten raw as salads are minimally processed and widely consumed foods. Risk factors for leafy greens contamination by Salmonella spp. and Norovirus were considered in the context of the whole food chain including agricultural production and processing. Available estimates of the prevalence of these pathogens (together with the use of Escherichia coli as an indicator organism in leafy greens were evaluated. Specific mitigation options relating to contamination of leafy greens were considered and qualitatively assessed. It was concluded that each farm environment represents a unique combination of numerous characteristics that can influence occurrence and persistence of pathogens in leafy greens production. Appropriate implementation of food safety management systems, including Good Agricultural Practices (GAP, Good Hygiene Practices (GHP and Good Manufacturing Practices (GMP, should be primary objectives of leafy green producers. The relevance of microbiological criteria applicable to production, processing and at retail/catering were considered. The current legal framework does not include microbiological criteria applicable at primary production which will validate and verify GAP and GHP. It is proposed to define a criterion at primary production of leafy greens which is designated as Hygiene Criterion, and E. coli was identified as suitable for this purpose. A Process Hygiene Criterion for E. coli in leafy green packaging plants or fresh cutting plants was considered and will also give an indication of the degree to which GAP, GHP, GMP or HACCP programs have been implemented. A Food Safety Criterion for Salmonella in leafy greens could be used as a tool to communicate to producers and processors that Salmonella should not be present in the product. Studies on the prevalence and infectivity of Norovirus are limited, and quantitative data on viral load are scarce making establishment of microbiological criteria for Norovirus on

  13. Sociedad por Acciones Simplificada

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    Carlos Andrés Arcila Salazar

    2009-06-01

    Full Text Available En Colombia, aspectos como la responsabilidad limitada; supresión de la llamada doctrina de ultra vires; duración ilimitada; eliminación de la regla, una acción, un voto; remedios al abuso de los derechos; posibilidad de eliminar prohibiciones a los administradores, libertad de establecer restricciones para la transferencia de acciones y la simplificación de los procedimientos de fusión; son inviables bajo nuestra legislación. Sin embargo, la Ley 1258 de 2008, ha incorporado al derecho societario colombiano un nuevo tipo societario híbrido, llamado “Sociedad por Acciones Simplificada”. Esta forma societaria híbrida se basa en un principio básico: garantizar amplia libertad a los empresarios en la estructuración de sus relaciones a través de disposiciones contractuales. La S.A.S. provee a los empresarios significativa flexibilidad contractual, a la vez que preserva beneficios como la limitación de la responsabilidad.

  14. Sociedad por Acciones Simplificada

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Arcila Salazar

    2009-07-01

    Full Text Available En Colombia, aspectos como la responsabilidad limitada; supresión de la llamada doctrina de ultra vires; duración ilimitada; eliminación de la regla, una acción, un voto; remedios al abuso de los derechos; posibilidad de eliminar prohibiciones a los administradores, libertad de establecer restricciones para la transferencia de acciones y la simplificación de los procedimientos de fusión; son inviables bajo nuestra legislación. Sin embargo, la Ley 1258 de 2008, ha incorporado al derecho societario colombiano un nuevo tipo societario híbrido, llamado “Sociedad por Acciones Simplificada”. Esta forma societaria híbrida se basa en un principio básico: garantizar amplia libertad a los empresarios en la estructuración de sus relaciones a través de disposiciones contractuales. La S.A.S. provee a los empresarios significativa flexibilidad contractual, a la vez que preserva beneficios como la limitación de la responsabilidad.

  15. Temperature inactivation of Feline calicivirus vaccine strain FCV F-9 in comparison with human noroviruses using an RNA exposure assay and reverse transcribed quantitative real-time polymerase chain reaction-A novel method for predicting virus infectivity.

    Science.gov (United States)

    Topping, J R; Schnerr, H; Haines, J; Scott, M; Carter, M J; Willcocks, M M; Bellamy, K; Brown, D W; Gray, J J; Gallimore, C I; Knight, A I

    2009-03-01

    A one-step reverse transcription quantitative real-time polymerase chain reaction (RT-QPCR) method in combination with RNase treatment and low copy number samples was developed in order to examine the effect of temperature on the ability of virus capsids to protect their RNA content. The method was applied to a non-cultivable virus (GII.4 norovirus) and Feline calicivirus vaccine strain F-9 (FCV) which is often used as a norovirus surrogate. Results demonstrated that FCV RNA is exposed maximally after 2min at 63.3 degrees C and this correlated with a greater than 4.5log reduction in infectivity as assessed by plaque assay. In contrast human GII.4 norovirus RNA present in diluted clinical specimens was not exposed maximally until 76.6 degrees C, at least 13.3 degrees C greater than that for FCV. These data suggest that norovirus possesses greater thermostability than this commonly used surrogate. Further, these studies indicate that current food processing regimes for pasteurisation are insufficient to achieve inactivation of GII.4 NoVs. The method provides a novel molecular method for predicting virus infectivity.

  16. The South to north variation of norovirus epidemics from 2006-07 to 2008-09 in Japan.

    Directory of Open Access Journals (Sweden)

    Shinako Inaida

    Full Text Available BACKGROUND: Norovirus (NoV is a major cause of gastroenteritis during the autumn and winter seasons in Japan as well as in other temperate climate regions. Most outbreaks are thought to occur by secondary attacks through person-to-person infection by fecal-oral route. Severe cases are found in young children or patients with chronic diseases. Clarifying the patterns of epidemic diffusion is important for considering effective monitoring and surveillance as well as possible prevention. METHODS: We considered the predominant viral genotype from the laboratory result obtained from Infectious Agents Surveillance Report (IASR of National Institute of Infectious Diseases (NIID. We investigated the increase of NoV cases nationwide for the 2006-07 to 2008-09 seasons using sentinel gastroenteritis data collected from about 3000 pediatric clinics on National Epidemiological Surveillance of Infectious Diseases (NESID acquired from the kriging method in the geographic information system (GIS. RESULTS: During these three seasons, the majority of the detected virus was GII.4, which ranged from 60.4 to 88.9%. The number of cases (per sentinel site at the peak week was 22.81 in the 2006-07 season and it decreased in the following seasons. NoV cases began to increase earlier in the southern areas and gradually extended into the northern areas, similarly, over the seasons. The average period from when the increase of cases was detected in the southern area to when it reached the northern area was 12.7 weeks. CONCLUSION: The decrease of the number of sentinel cases at the peak week may suggest the development of herd immunity after a period of high prevalence. Although the NoV epidemic is thought to be associated with cold weather, its cases first increased in the southern area with relatively warm temperature, indicating there are other climate factors involved. Geographic study using the sentinel data could enhance the monitoring and surveillance of and

  17. High protective efficacy of probiotics and rice bran against human norovirus infection and diarrhea in gnotobiotic pigs

    Directory of Open Access Journals (Sweden)

    Shaohua Lei

    2016-11-01

    Full Text Available Probiotics have been recognized as vaccine adjuvants and therapeutic agents to treat acute gastroenteritis in children. We previously showed that rice bran reduced human rotavirus diarrhea in gnotobiotic pigs. Human noroviruses (HuNoVs are the major pathogens causing nonbacterial acute gastroenteritis worldwide. In this study, Lactobacillus rhamnosus GG (LGG and Escherichia coli Nissle 1917 (EcN were first screened for their ability to bind HuNoV P particles and virions derived from clinical samples containing HuNoV genotype GII.3 and GII.4, then the effects of LGG+EcN and rice bran on HuNoV infection and diarrhea were investigated using the gnotobiotic pig model. While LGG+EcN colonization inhibited HuNoV shedding, probiotic cocktail regimens in which rice bran feeding started 7 days prior to or 1 day after viral inoculation in the LGG+EcN colonized gnotobiotic pigs exhibited high protection against HuNoV diarrhea and shedding, characterized by significantly reduced incidence (89% versus 20% and shorter mean duration of diarrhea (2.2 versus 0.2 days, as well as shorter mean duration of virus shedding (3.2 versus 1.0 days. In both probiotic cocktail groups, the diarrhea reduction rates were 78% compared with the control group, and diarrhea severity was reduced as demonstrated by the significantly lower cumulative fecal scores. The high protective efficacy of the probiotic cocktail regimens was attributed to stimulation of IFN-γ+ T cell responses, increased production of intestinal IgA and IgG, and maintenance of healthy intestinal morphology (manifested as longer villi compared with the control group. Therefore, probiotic cocktail regimens containing LGG+EcN and rice bran may represent highly efficacious strategies to prevent and treat HuNoV gastroenteritis, and potentially other human enteric pathogens.

  18. Year-round prevalence of norovirus in the environment of catering companies without a recently reported outbreak of gastroenteritis.

    Science.gov (United States)

    Boxman, Ingeborg L A; Verhoef, Linda; Dijkman, Remco; Hägele, Geke; Te Loeke, Nathalie A J M; Koopmans, Marion

    2011-05-01

    Food handlers play an important role in the transmission of norovirus (NoV) in food-borne outbreaks of gastroenteritis (GE). In a year-round prevalence study, the prevalence of NoV in catering companies without recently reported outbreaks of GE was investigated and compared to the observed prevalence in catering companies with recently reported outbreaks. Swab samples were collected from surfaces in the kitchens and (staff) bathrooms in 832 randomly chosen companies and analyzed for the presence of NoV RNA. In total, 42 (1.7%) out of 2,496 environmental swabs from 35 (4.2%) catering companies tested positive. In contrast, NoV was detected in 147 (39.7%) of the 370 samples for 44 (61.1%) of the 72 establishments associated with outbreaks of gastroenteritis. NoV-positive swabs were more frequently found in winter, in specific types of companies (elderly homes and lunchrooms), and in establishments with separate bathrooms for staff. We found a borderline association with population density but no relation to the number of employees. Sequence analysis showed that environmental strains were interspersed with strains found in outbreaks of illness in humans. Thus, the presence of NoV in catering companies seemed to mirror the presence in the population but was strongly increased when associated with food-borne GE. Swabs may therefore serve as a valuable tool in outbreak investigations for the identification of the causative agent, although results should be interpreted with care, taking into account all other epidemiological data.

  19. Evolutionary Constraints on the Norovirus Pandemic Variant GII.4_2006b over the Five-Year Persistence in Japan

    Science.gov (United States)

    Sato, Hironori; Yokoyama, Masaru; Nakamura, Hiromi; Oka, Tomoichiro; Katayama, Kazuhiko; Takeda, Naokazu; Noda, Mamoru; Tanaka, Tomoyuki; Motomura, Kazushi

    2017-01-01

    Norovirus GII.4 is a major cause of global outbreaks of viral gastroenteritis in humans, and has evolved by antigenic changes under the constantly changing human herd immunity. Major shift in the pandemic GII.4 strain periodically occurs concomitant with changes in the antigenic capsid protein VP1. However, how the newly emerged strain evolves after the onset of pandemic remains unclear. To address this issue, we examined molecular evolution of a pandemic lineage, termed the GII.4_2006b, by using the full-length viral genome and VP1 sequences (n = 317) from stools collected at 20 sites in Japan between 2006 and 2011. Phylogenetic tree showed a radial diversification of the genome sequences of GII.4_2006b, suggesting a rapid genetic diversification of the GII.4_2006b population from a few ancestral variants. Impressively, amino acid sequences of the variable VP1 in given seasons remained as homogeneous as those of viral enzymes under annual increase in the nucleotide diversity in the VP1 coding region. The Hamming distances between the earliest and subsequent variants indicate strong constraints on amino acid changes even for the highly variable P2 subdomain. These results show the presence of evolutionary constraints on the VP1 protein and viral enzymes, and suggest that these proteins gain near maximal levels of fitness benefits in humans around the onset of the outbreaks. These findings have implications for our understanding of molecular evolution, mechanisms of the periodic shifts in the pandemic NoV GII.4 strains, and control of the NoV GII.4 pandemic strain.

  20. Hospitalization due to norovirus and genotypes of rotavirus in pediatric patients, state of Espírito Santo

    Directory of Open Access Journals (Sweden)

    Leandro Rua Ribeiro

    2008-03-01

    Full Text Available Viruses are the leading cause for hospitalization due to gastroenteritis worldwide. Group A rotaviruses (RV are the most prevalent and are assorted in glycoproteins (G and protease sensitive (P dual genotypes based on polymorphic genes that encode the external VP7 and VP4 capsid proteins, respectively. Noroviruses (NoV have increasingly answered by sporadic gastroenteritis. This study aimed to determine the prevalence of NoV and RV in 68 hospitalized children, between July 2004 and November 2006, at a pediatric hospital in Vitória city, state of Espírito Santo, Southeastern Brazil. Nucleic acid was extracted from fecal suspension following the guanidine-silica procedure. Reverse transcriptase-polymerase chain reaction (RT-PCR and polyacrylamide gel electrophoresis were employed for NoV and RV detection, respectively. RV genotyping was accomplished using RT-PCR followed by heminested multiplex PCR with specific primers for the most prevalent types of G and P. Fecal samples were positive for NoV and RV in 39.7% (27/68 and 20.5% (14/68, respectively and together were responsible for 60% (41/68 of the cases. RV genotypes were: 50% G9P[8], 28.7% G2P[4], 7.1% G1P[8], G2P[8] and G?P[8]. Vomit was a prominent manifestation observed in 92% and 85% of the NoV and RV cases, respectively. The median hospitalization was 5 and 5.5 days for the patients infected with NoV and RV, respectively. The data showed that NoV prevailed over RV and it also corroborated the emergence of RV G9 genotype followed by G2P[4], reinforcing the need for RV genotype surveillance.