Brote de enfermedad transmitida por alimentos en el distrito de Catache, provincia de Santa Cruz, departamento de Cajamarca. Abril 2007

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Suarez, Victor

2007-01-01

De acuerdo con la información proporcionada por la Dirección de Epidemiología de la DIRESA Cajamarca, durante la primera semana de abril se ha producido un brote de una enfermedad transmitida por alimentos en el distrito de Catache, provincia de Santa Cruz, departamento de Cajamarca, con 49 casos. Los primeros casos se presentaron el 3 de abril y los últimos seis casos fueron atendidos en el C.S. Catache el día 9 de abril. El 100% de los casos presentaron nauseas, 85,7% vómitos y 75,5% cef...

Brote epidémico de neumonías por Legionella pneumophila en niños cubanos

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Roberto Razón Behar

2002-09-01

Full Text Available La Legionella pneumophila es uno de los patógenos responsable de neumonías atípicas, a través de la inhalación de aerosoles o aspiración de líquidos infectados. Se detectó un brote epidémico de neumonías por Legionella, originado por la aspiración de agua contaminada de una piscina en un grupo de niños cubanos. El agente causal se identificó en 5 de 9 pacientes, por la técnica de inmunofluorescencia indirecta en muestras de sueros pareados. Los síntomas y signos más frecuentes fueron malestar general, anorexia, astenia, fiebre persistente de 39 °C a 40 °C (103 °F a 105 °F, mialgias, cefaleas, náuseas, vómitos, dolor abdominal, diarreas, tos húmeda, dolor torácico y polipnea. Durante el desarrollo de la enfermedad, el tratamiento antibiótico fue empírico (incluyendo los macrólidos, por no tener confirmado el diagnóstico. Todos los pacientes evolucionaron satisfactoriamente. Se reportó un brote epidémico de neumonías por Legionella en niños por primera vez en Cuba, lo cual tiene importancia clínica y epidemiológica.The legionella pneumophila is one of the pathogens responsible for atypic pneumonias by the inhalation of aerosols or aspiration of infected liquids. An epidemic outbreak of pneumonias caused by Legionella was detected among a group of Cuban children. It was originated by the aspiration of contaminated water in a swimming pool. The causal agent was identified in 5 of 9 patients by using the indirect immunofluorescence technique in samples of matched sera. The most frequent symptoms and signs were malaise, anorexia, asthenia, persistent fever from 39°C to 40°C (103° F to 105° F, myalgias, headache, nauseas, vomits, abdominal pain, diarrheas, moist cough, thoracic pain and polypnoea. The antibiotic treatment was empiric (including the macrolides during the development of the disease, since the diagnosis was not confirmed. The patients’ evolution was satisfactory. An epidemic outbreak of pneumonias

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.

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.

Mortalidad por enfermedad de Chagas: A propósito de los brotes de Chagas agudo como enfermedad reemergente de transmisión alimentaria

OpenAIRE

Rísquez, Alejandro

2009-01-01

Tras la ocurrencia de los primeros brotes de Chagas agudos en la capital (diciembre 2007) y Estado Vargas (marzo 2009) por trasmisión oral, se procedió a una revisión de la mortalidad por la enfermedad registrada entre 1997 y 2006, cuyos datos se analizaron de acuerdo a la edad, sexo y forma de presentación. El número absoluto de muertes sigue siendo elevado con promedio de 796 muertes anuales, de predominio en el sexo masculino, la mayoría en después de los 60 años de edad. Llama la atención...

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

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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.

Brote de rabia urbana transmitida por perros en el distrito de Santa Marta, Colombia, 2006-2008

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Páez, Andrés; Rey, Gloria; Agudelo, Carlos; Dulce, Álvaro; Parra, Edgar; Díaz-Granados, Hernando; Heredia, Damaris; Polo, Luis

2009-01-01

Introducción. En el distrito de Santa Marta ocurrió un brote de rabia urbana entre abril de 2006 y enero de 2008, con cuatro casos fatales en humanos y 28 en perros. Objetivos. Describir el brote, las técnicas de diagnóstico de laboratorio y las acciones de control de foco empleadas. Medir el impacto de la vacunación antirrábica canina en términos de seroconversión de anticuerpos neutralizantes. Discutir el significado epidemiológico y las implicaciones en salud pública. Materiales y métodos....

Brote de rabia urbana transmitida por perros en el distrito de Santa Marta, Colombia, 2006-2008

OpenAIRE

Andrés Páez; Gloria Rey; Carlos Agudelo; Alvaro Dulce; Edgar Parra; Hernando Díaz-Granados; Damaris Heredia; Luis Polo

2009-01-01

Introducción. En el distrito de Santa Marta ocurrió un brote de rabia urbana entre abril de 2006 y enero de 2008, con cuatro casos fatales en humanos y 28 en perros. Objetivos. Describir el brote, las técnicas de diagnóstico de laboratorio y las acciones de control de foco empleadas. Medir el impacto de la vacunación antirrábica canina en términos de seroconversión de anticuerpos neutralizantes. Discutir el significado epidemiológico y las implicaciones en salud pública. Materiales y mé...

Clostridium difficile outbreak in Costa Rica: control actions and associated factors Brote de infección por Clostridium difficile en Costa Rica: medidas de control y factores asociados

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Roy A. Wong-McClure

2012-12-01

Full Text Available OBJECTIVE: To describe interventions implemented during a nosocomial outbreak of Clostridium difficile in a general hospital in Costa Rica from December 2009 to April 2010 in order to achieve outbreak control and the factors determined to be associated with C. difficile infection. METHODS: Laboratory-confirmed cases of C. difficile were analyzed to describe the outbreak pattern and intervention measures implemented. Cases were selected and recruited in a case-control study. Controls were selected from the same services and time period as the cases. Evaluated exposures included underlying medical conditions and treatments administered before the onset of symptoms. RESULTS: The mean ages in case and control groups were 62.3 and 55.3 years, respectively. Control measures included a hand-hygiene campaign, deep disinfection of hospital surfaces, strict isolation of cases, use of personal protection equipment, and restriction of antibiotic use. The adjusted attributable risks associated with the outbreak were diabetes [odds ratio (OR 3.4, 95% confidence interval (CI 1.5-7.7], chronic renal failure (OR 9.0, 95% CI 1.5-53.0, and prescribing ceftazidime (OR 33.3, 95% CI 2.9-385.5 and cefotaxime (OR 20.4, 95% CI 6.9-60.3. CONCLUSIONS: Timely implementation of control measures resulted in reduced infection transmission and successful control of the outbreak. Conditions associated with C. difficile infection were similar to those found in previously described outbreaks of this bacterium.OBJETIVO: Describir las intervenciones ejecutadas durante un brote intrahospitalario de infección por Clostridium difficile en un hospital general de Costa Rica desde diciembre del 2009 hasta abril del 2010 para lograr el control del brote y de los factores asociados a la infección por C. difficile. MÉTODOS: Se analizaron los casos de infección por C. difficile que se habían confirmado mediante pruebas de laboratorio a fin de describir las características del brote y

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.

Análisis de un brote de meningitis viral en la provincia de Tucumán, Argentina

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Freire María Cecilia

2003-01-01

Full Text Available OBJETIVO: Confirmar la existencia de un brote de meningitis viral en 1996 en la provincia de Tucumán, Argentina, y estudiar sus características epidemiológicas. MÉTODOS: Se analizó información obtenida del Sistema Nacional de Vigilancia Epidemiológica (SINAVE del Ministerio de Salud de Argentina para el período de 1994-1998, la cual fue provista por la Dirección de Epidemiología de dicho ministerio. Para el cálculo de incidencias se usaron estimaciones poblacionales para los años 1994-1998 realizadas por el Instituto Nacional de Estadística y Censos (INDEC sobre la base del censo de 1991. El estudio de frecuencias se realizó mediante el análisis de tablas de contingencia de doble entrada, según el método de ji cuadrado con la corrección de Yates. Se consideró significativo el resultado cuando P < 0,05. RESULTADOS: Se confirmó la presencia de un brote de 189 casos entre el 11 de febrero y el 18 de mayo de 1996. La incidencia de casos en la provincia mostró un aumento entre 1995 y 1996 (de 0,5 a 19,3 casos por 100000 años-persona y dicha incidencia fue significativamenrte mayor que la observada en el resto del país (19,3 frente a 2,8 casos por 100000 años-persona. El 75,1% de los casos ocurrió en niños menores de 9 años (142/189. Se detectó la presencia de Enterovirus (EV en 65 de las 111 muestras estudiadas (58,6%. Mediante la reacción en cadena de la polimerasa (RCP anidada con transcripción inversa se logró detectar EV en 66,3% (53/80 de los casos estudiados por este método, en comparación con solo 29,6% (24/81 de los estudiados mediante aislamiento viral. Se identificó echovirus tipo 4 en 15 (68% en las 22 muestras tipificadas (5 por aislamiento, 3 por secuenciación y 7 por ambos métodos. Este brote demuestra la capacidad de los EV para diseminarse y producir enfermedad en la población. Durante el brote, por lo menos 56% de los casos fueron hospitalizados. CONCLUSIONES: El uso de métodos moleculares

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

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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.

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

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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.

Aislamiento rápido del virus dengue 3 por el método de shell vial en el brote de dengue en Lima

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Victoria Gutiérrez P

2005-07-01

Full Text Available El aislamiento de virus dengue con los métodos tradicionales demora hasta un mes, en situaciones de emergencia como el brote de dengue clásico en el distrito de Comas-Lima entre abril y mayo de 2005, es necesario un diagnóstico precoz. Se procesaron 117 muestras de sueros de pacientes con diagnóstico clínico de dengue clásico en fase virémica procedentes la zona del brote, mediante el método de shell vial para el aislamiento del virus dengue en la línea celular C6-36, se identificó el serotipo del virus mediante inmunofluorescencia indirecta (IFI empleando anticuerpos monoclonales. Se logró el aislamiento del virus DEN-3 al quinto día de cosecha en el 48,7% (57/117 de los sueros. Los resultados sugieren que el método de shell vial, por el menor tiempo de aislamiento que el método tradicional, puede ser implementado como método de diagnóstico y usado en la vigilancia epidemiológica del virus dengue.

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

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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

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

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

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Probable brote de transmisión oral de enfermedad de Chagas en Turbo, Antioquia

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Juan Fernando Ríos

2011-03-01

Conclusión. Se identificó un probable brote agudo de enfermedad de Chagas en Antioquia y se plantea como hipótesis la transmisión por vía oral, mediante la ingestión de T. cruzi en alimentos contaminados con restos de triatominos o excrementos de marsupiales.

Brote de bacteriemia por Serratia marcescens en pacientes portadores de catéteres tunelizados en hemodiálisis secundario a colonización de la solución antiséptica. Experiencia en 4 centros

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José L. Merino

2016-11-01

Conclusiones: Las bacteriemias por gérmenes no convencionales deben ponernos sobre aviso para investigar posibles brotes. La aplicación de una solución contaminada por S. marcescens en los catéteres en hemodiálisis fue la vía de bacteriemia. El tratamiento antibiótico intravenoso y el sellado de los catéteres permitió una excelente supervivencia tanto de los pacientes como de los catéteres.

Outbreak of rotavirus gastroenteritis with high mortality, Nicaragua, 2005 Brote de gastroenteritis por rotavirus con alta mortalidad, Nicaragua, 2005

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Juan José Amador

2008-04-01

Full Text Available OBJECTIVES: We investigated a nationwide outbreak of severe rotavirus gastroenteritis in Nicaragua in children under 5 years old, leading to many consultations, hospitalizations, and deaths. We questioned whether a vaccine might have prevented these illnesses and deaths, sought to identify risk factors for death, and developed a clinical profile of children hospitalized with diarrhea. METHODS: We conducted a case-control study to determine whether children who died had access to routine immunizations, a proxy predicting access to a rotavirus vaccine. We identified risk factors for death among children who died in the outbreak compared with surviving age-matched controls with diarrhea. We collected stools, clinical data, and immunization data on children hospitalized for diarrhea to test for rotavirus, develop the profile, and forecast future access to a rotavirus vaccine. RESULTS: The outbreak from February to April 2005 caused 47 470 consultations and 52 deaths. Approximately 80% of cases and controls and 60% of children hospitalized with diarrhea had access to routine immunizations and would likely have had access to a rotavirus vaccine. With a vaccine efficacy of 85%, up to 51% of severe rotavirus cases and up to 68% of deaths could have been prevented if a rotavirus vaccine were available as part of routine child-hood immunizations. Study of 35 case-control pairs indicated that severe illnesses, malnutrition, and care by traditional healers were risk factors for death. Rotavirus was found in 42% of samples from hospitalized children and was associated with severe disease and dehydration. CONCLUSIONS: The impact of the seasonal outbreaks of rotavirus disease could be diminished with a rotavirus vaccine, improvements in oral rehydration programs, and training of traditional healers in the proper management of children with acute diarrhea.OBJETIVOS: Se investigó un brote nacional de gastroenteritis grave por rotavirus en niños menores de 5 a

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

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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.

Brote de rabia urbana transmitida por perros en el distrito de Santa Marta, Colombia, 2006-2008

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Andrés Páez

2009-09-01

El control del brote se logró 20 meses después del primer caso en perros y 14 meses después de haberse iniciado la primera vacunación masiva en animales. Es necesario implementar y mantener acciones para el control de la rabia urbana y evitar su impacto en los humanos.

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

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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...

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

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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.

Caracterización de dos brotes de fiebre tifoidea en Apartadó, Antioquia, 2005

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Nora María Cardona-Castro

2007-06-01

Conclusiones. La electroforesis en campo pulsado estableció la presencia de dos brotes, que inicialmente, por epidemiología y pruebas fenotípicas del patógeno, habían sido descritos como uno solo. Además, permitió diferenciar dos aislamientos de origen clonal diferente, que indicaron casos aislados. No se pudo corroborar la fuente de infección en el agua.

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.

BROTE DE LEGIONELOSIS EN UN RESTAURANTE DE LA COMUNIDAD DE MADRID

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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.

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 objetivo 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 Excel 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 sintomatología 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.

Brote de fiebre amarilla selvática en Colombia 2004

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Pilar Bernal M.

2004-03-01

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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

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.

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

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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.

NOROVIRUS INFECTION (SYSTEMATIC REVIEW

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N. I. Khokhlova

2018-01-01

Full Text Available The share of norovirus infection is 17–20% of all cases of acute gastroenteritis in the world. The dominant II genogroup of noroviruses is characterized by rapid variability. The new recombinant norovirus GII.P16-GII.2 caused a sharp increase in the incidence of gastroenteritis in Asian and European countries during the winter season 2016–2017. The epidemiological features of norovirus infection are long-term excretion of the pathogen from the body of patients and carriers of viruses, especially in persons with immunosuppression; the implementation of various transmission routes (food, water, contact, aerosol, high contagiosity, winter seasonality in the countries of the northern hemisphere. In recent years, two human systems for the cultivation of noroviruses in vitro have been created, a double tropism of noroviruses has been established for immune cells and epithelial cells of the intestine, and the life cycle of noroviruses has been studied. The microbiota and its members can be either protective or stimulating for norovirus infection. Lactobacillus may play a protective role against norovirus infection. The existence of chronic norovirus infection lasting from several months to several years is proved, especially in patients with immunodeficiency. Severe form of norovirus infection and deaths are more often recorded in young children, the elderly, patients with comorbidity and immunocompromised individuals. The clinical picture of norovirus gastroenteritis is similar in many respects to other viral gastroenteritis, which determines the need for laboratory verification of the diagnosis. The polymerase chain reaction method with reverse transcription is the most widely used in the world for diagnosing infection in patients and for detecting the virus in food and environmental objects. There are still no approved vaccines and antiviral drugs against this infection. Recommended therapeutic interventions include, along with rehydration with

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

Prevent the Spread of Norovirus

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... is also a major cause of outbreaks in restaurants and catered-meal settings if contaminated food is ... 2014 CDC Norovirus web site Norovirus Treatment Norovirus Trends and Outbreaks For Food Handlers: Norovirus and Working ...

Inactivation of Norovirus by Lemongrass Essential Oil Using a Norovirus Surrogate System.

Science.gov (United States)

Kim, Ye Won; You, Hyun Ju; Lee, Soyoung; Kim, Bomi; Kim, Do Kyung; Choi, Joo-Bong; Kim, Ji-Ah; Lee, Hee Jung; Joo, In Sun; Lee, Jeong Su; Kang, Dong Hyun; Lee, Giljae; Ko, Gwang Pyo; Lee, Sung-Joon

2017-08-01

This study investigated the effect of lemongrass essential oil (LGEO) on the infectivity and viral replication of norovirus. Murine norovirus 1 (MNV-1), a surrogate of human norovirus, was preincubated with LGEO and then used to infect RAW 264.7 cells in a plaque reduction assay. LGEO exhibited a significant reduction in MNV-1 plaque formation in both time- and dose-dependent manners. The quantification of viral genome by quantitative real-time PCR showed similar results in line with those of the plaque reduction assay. It was revealed that citral, a single compound in LGEO, showed dramatic reduction in MNV-1 infectivity (-73.09% when using a treatment of 0.02%, v/v). The inhibitory activity of LGEO on viral replication was further investigated in HG23 cells that harbored a human norovirus replicon. LGEO treatment significantly reduced viral replication in HG23 cells, which suggests that LGEO may have dual inhibitory activities that inactivate viral coat proteins required for viral infection and suppress norovirus genome replication in host cells. In animal experiments, oral administration of murine norovirus preincubated with LGEO significantly suppressed virus infectivity in vivo. Collectively, these results suggest that LGEO, in particular the LGEO component citral, inactivates the norovirus and its subsequent replication in host cells. Thus, LGEO shows promise as a method of inhibiting norovirus within the food industry.

Manifestaciones sistémicas del brote dentario

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Juana María Abreu Correa

1997-12-01

Full Text Available Se realizó un estudio para comprobar la presencia de manifestaciones sistémicas asociadas con el brote dentario, aspecto que ha sido motivo de discrepancias entre médicos y estomatólogos durante mucho tiempo. Para la obtención de los datos se entrevistaron a las madres de 121 infantes, cuyas edades oscilaron entre 6 y 12 meses, por considerarse las edades más propensas a estas manifestaciones. Se aplicó el método estadístico de prueba de contraste de hipótesis. No hubo diferencias en relación con el sexo. Las madres refirieron los síntomas y signos que se presentan durante la erupción dentaria y que se expresan en por cientos; otro grupo planteó que la erupción fue asintomática. Entre las manifestaciones o patologías asociadas, las diarreas tuvieron una mayor incidencia, seguidas de la fiebre, el estado catarral y los vómitos. También estuvieron presentes, aunque con menos incidencia, la irritabilidad y la dermatitis. Según las pruebas estadísticas los resultados fueron altamente significativos, lo que demuestra la relación existente entre manifestaciones sistémicas y el brote dentario.It was conducted a study to prove the presence of systemic manifestations associated with tooth eruption, an aspect that has been the cause of differences between doctors and stomatologists for a long time. In order to obtain information the mothers of 121 infants aged 6-12 months were interviewed as they had more possibilities to present these manifestations. The statistical method of hypothesis contrast test was applied. There were no differences in connection with sex. Mothers explained the symptoms and signs appearing during tooth eruption that are expressed in percents. The other group said that the eruption was asymptomatic. Among the associated manifestations or pathologies, diarrheas had the greatest incidence, followed by fever, cold, and vomits. Irritability and dermatitis were also present but with less incidence. According to the

Brotes de babesiosis y anaplasmosis bovina diagnosticados en el INTA Salta, Argentina: período 2006-2016

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ARAOZ V

2017-12-01

Full Text Available Se realizó un estudio retrospectivo de brotes de babesiosis y anaplasmosis (tristeza parasitaria bovina, TPB ocurridos entre 2006 y 2016 en el Noroeste argentino (NOA para evaluar algunos aspectos epidemiológicos y clínicos de estas enfermedades. De 4.398 muestras para diagnóstico, 238 (5,4% tuvieron sospechas de TPB, las cuales se confirmaron en 106 (44,3% casos por observación microscópica de los agentes causales. Cuarenta y siete (44,3% brotes se debieron a Anaplasma marginale, 40 (37,7% a Babesia bovis y 14 (13,2% a Babesia bigemina. En cinco (4,7% focos de babesiosis no se determinó la especie causal de Babesia. Los brotes se diagnosticaron en 62 establecimientos ganaderos de cuatro provincias (Salta, Jujuy, Santiago del Estero y Chaco. La mayoría ocurrieron en verano y otoño, con máxima incidencia en abril y nula en setiembre para ambas noxas. Las vacas adultas fueron la categoría de ganado más afectada. En 58% (61/106 de los brotes murió al menos un bovino, con un número promedio de cuatro muertes por brote. Se concluye que la TPB continúa incidiendo negativamente en la producción bovina del NOA. SUMMARY. Bovine babesiosis and anaplasmosis outbreaks diagnosed at INTA Salta, Argentina: 2006-2016. A retrospective study of babesiosis and anaplasmosis outbreaks (tick fever, TF was made, which occurred from 2006 to 2016 in Northwest Argentina (NWA, to evaluate clinical and epidemiological aspects of these diseases. From 4,398 specimens, 238 (5.4% were associated with suspicions of TF and 106 of these cases (44.3% were confirmed as TF outbreaks by microscopic observation of causal agents. Forty seven (44.3% were due to Anaplasma marginale, 40 (37.7% to Babesia bovis and 14 (13.2% to Babesia bigemina. In five (4.7% outbreaks of babesiosis, Babesia species were not determined. Outbreaks were diagnosed at 62 different cattle ranches in four provinces (Salta, Jujuy, Santiago del Estero and Chaco. The outbreaks occurred mostly during

Brotes escolares de gripe (H1N1 2009 en Cataluña

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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.

Norovirus: Food Handlers

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

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

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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.

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.

Norovirus: U.S. Trends and Outbreaks

Science.gov (United States)

... harvested 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 ( ...

Personalized Genetic Testing and Norovirus Susceptibility

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Natalie Prystajecky

2014-01-01

Full Text Available BACKGROUND: The availability of direct-to-consumer personalized genetic testing has enabled the public to access and interpret their own genetic information. Various genetic traits can be determined including resistance to norovirus through a nonsense mutation (G428A in the FUT2 gene. Although this trait is believed to confer resistance to the most dominant norovirus genotype (GII.4, the spectrum of resistance to other norovirus strains is unknown. The present report describes a cluster of symptomatic norovirus GI.6 infection in a family identified to have norovirus resistance through personalized genetic testing.

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

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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.

Intoxicación por atropina en estudiantes del colegio de Capiro-Piñas

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Janette Esther Eras Carranza

2017-06-01

Full Text Available Introducción: La atropina es un producto que inicialmente estimula el Sistema Nervioso Central y luego lo deprime. Presenta efecto antiespasmódico sobre músculo liso reduciendo las secreciones salivales y bronquiales, así como reduce la transpiración, incrementa la frecuencia cardiaca y la visión se torna en borrosa. Objetivo: Identificar la magnitud del brote de intoxicación por atropina acorde a la curva epidémica, la fuente de intoxicación y el tipo de transmisión. Descripción de los casos: El 2 de septiembre del año 2008 se notificaron cuatro casos de adolescentes hospitalizadas entre 12 a 18 años de edad, todas de sexo femenino con sintomatología dada por mareos, cefalea y pérdida de conocimiento, el diagnóstico planteado fue intoxicación por atropina. La magnitud del brote fue focalizado al grupo de adolescentes del sexo femenino con tasa de ataque de 21.3%, el grupo de edad fue de 15 a 19 años. La duración del brote fue de cuatro días de, la fuente de intoxicación fue común a partir del sitio donde tentativamente estuvo dispersa la escopolamina, el aula del colegio. Conclusiones: Se trató de un brote que afectó a adolescentes del sexo femenino, tuvo una corta duración y una fuente común de origen químico. Por medio del laboratorio se confirmó la presencia de escopolamina en las muestras de sangre y no hubo trasmisión en estos casos.

[Noroviruses: leading cause of gastroenteritis].

Science.gov (United States)

Delacour, H; Dubrous, P; Koeck, J L

2010-04-01

Although noroviruses were the first viral agents to be linked to gastrointestinal disease, they were long considered a secondary cause far behind rotaviruses. Development of molecular-based diagnostic techniques has provided clearer insight into the epidemiological impact of noroviruses that are now recognized not only as the leading cause of non-bacterial gastroenteritis outbreaks but also as an important cause of sporadic gastroenteritis in both children and adults. Norovirus infection is generally characterized by mild acute vomiting and diarrhea usually lasting for only a few days, but it can lead to more severe and potentially life-threatening symptoms in high-risk groups such as young children, elderly, and immunodeficient persons. It has been demonstrated that they are present in tropical countries. Molecular epidemiological studies have documented the great genetic diversity of noroviruses with regular emergence of variants. Since no vaccine is available, prevention on norovirus infection depends mainly on strict personal and community hygiene measures.

Brote de histoplasmosis aguda en un grupo familiar: identificación de la fuente de infección

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Roberto Alonso Jiménez

2002-06-01

Full Text Available Se informa un brote de histoplasmosis ocurrido en los integrantes de una familia y que comprometió a cuatro personas, dos mujeres, una niña y un hombre. El caso índice consultó por sintomatología respiratoria grave, de comienzo súbito, que requirió hospitalización. En los otros casos, la infección cursó de manera asintomática pero se puso en evidencia por la reactividad en las pruebas serológicas con histoplasmina. La búsqueda de una fuente común de contagio llevó a sospechar que era la tierra de un vivero que se había utilizado como fertilizante de las plantas caseras. Las suspensiones de las tierras de las macetas sirvieron para inocular ratones BALB/c, de cuyos órganos fue posible aislar el agente etiológico, Histoplasma capsulatum var. capsulatum. Si bien la histoplasmosis es más frecuente en ciertas ocupaciones y es propia de áreas rurales, las epidemias y los brotes son ahora comunes en áreas urbanas debido a actividades como la urbanización masiva, la tala de árboles, las demoliciones y el uso de tierras enriquecidas con abonos orgánicos (gallinaza, guano. Se llama la atención sobre el peligro que representa esta última actividad.

Brote de shigelosis en la ciudad de Luján, Argentina

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Anabella Della Gaspera

2015-06-01

Full Text Available El objetivo del estudio fue describir un brote por Shigella sonnei ocurrido en julio de 2012 en Luján, Buenos Aires, Argentina. Estuvieron afectadas 5 personas que asistieron a una reunión familiar, donde consumieron una rosca vienesa de elaboración artesanal adquirida en un comercio. Todos presentaron fiebre, dolores articulares, escalofríos y diarrea no sanguinolenta con mucus. Se realizaron coprocultivos en los afectados y análisis microbiológicos de los ingredientes. Se aisló y caracterizó S. sonnei de todos los pacientes y de la crema de almendras empleada en la preparación de la rosca vienesa. A los aislamientos se les determinó el perfil de sensibilidad a los antimicrobianos y el genético por electroforesis en campo pulsado. Los resultados demostraron la relación genética de los aislamientos, y esto confirmó la ocurrencia de los casos por exposición a una misma fuente de infección, la crema de almendras. Al ser un ingrediente industrial, de improbable contaminación inicial, la crema de almendras podría haber sufrido una contaminación durante la manipulación en la panadería.

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.

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

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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.

Descripción de un brote de enfisema y edema pulmonar agudo del bovino (EPAB) en Parral (Chile)

OpenAIRE

H. URRUTIA; C. BREVIS; M. QUEZADA; S. DONOSO

1997-01-01

Se describe un brote de enfisema y edema alveolar agudo del bovino (EPAB) ocurrido en la zona centro-sur a fines del verano de 1995. Los animales Frisón negro, de aproximadamente 2 años de edad, fueron afectados después de cambiarse de una pradera fibrosa a una suculenta de alfalfa. La mortalidad por esta causa fue de un 23%. Las principales lesiones encontradas en la necropsia fueron enfisema y edema intersticial intenso del pulmón, lo cual fue corroborado histopatológicamente, encontrándose...

Descripción de un brote de enfisema y edema pulmonar agudo del bovino (EPAB) en Parral (Chile)

OpenAIRE

URRUTIA, H.; BREVIS, C.; QUEZADA, M.; DONOSO, S.

1997-01-01

Se describe un brote de enfisema y edema alveolar agudo del bovino (EPAB) ocurrido en la zona centro-sur a fines del verano de 1995. Los animales Frisón negro, de aproximadamente 2 años de edad, fueron afectados después de cambiarse de una pradera fibrosa a una suculenta de alfalfa. La mortalidad por esta causa fue de un 23%. Las principales lesiones encontradas en la necropsia fueron enfisema y edema intersticial intenso del pulmón, lo cual fue corroborado histopatológicamente, encontrándos...

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

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.

Human Noroviruses and Sporadic Gastroenteritis

Centers for Disease Control (CDC) Podcasts

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.

Dental care associated with an outbreak of HIV infection among dialysis patients Atención dental asociada con un brote de infección por VIH en pacientes sometidos a diálisis

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Leonelo E. Bautista

1997-09-01

Full Text Available An outbreak of 14 cases of human immunodeficiency virus (HIV infection was discovered by chance in May 1993 among hemodialysis patients at a university hospital in Bucaramanga, Colombia. The outbreak occurred in 1992. Stored sera were used to establish the probable period of infection (PPI for 10 of the 14 cases. A nested case-control study was carried out to evaluate possible transmission mechanisms. The health care experience of each HIV-positive patient during that patient’s PPI was compared to the experience of time-matched controls. Only invasive dental procedures were significantly associated with the risk of infection. Patients upon whom invasive dental procedures were performed during their PPIs had an average risk of HIV infection 8.15 times greater than comparable controls (P = 0.006, and seven out of nine cases of HIV infection with known PPIs in 1992 had an invasive dental procedure performed one to six months before seroconversion. None of the dental care personnel were found to be infected. Based on the available evidence, it seems most likely that the infection was transmitted from patient to patient by contaminated dental instruments.En mayo de 1993 se descubrió fortuitamente un brote de 14 casos de infección por virus de la inmunodeficiencia humana (VIH en pacientes sometidos a hemodiálisis en un hospital universitario de Bucaramanga, Colombia. El brote tuvo lugar en 1992. Se usaron sueros almacenados para determinar el período de infección probable (PI de 10 de los 14 casos y se llevó a cabo un estudio de casos y controles anidado a fin de evaluar los posibles mecanismos de transmisión. La atención de salud recibida por cada paciente positivo a VIH durante su PIP se comparó con la atención recibida por controles apareados con los casos en tiempo. Solamente los procedimientos odontológicos invasores mostraron una asociación significativa con el riesgo de infección. Los pacientes sometidos a procedimientos dentales

Recent advances in understanding noroviruses [version 1; referees: 2 approved

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Eric Bartnicki

2017-01-01

Full Text Available 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.

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. Copyright © 2015. Published by Elsevier Ltd.

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

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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.

Ultrasensitive norovirus detection using DNA aptasensor technology.

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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.

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

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Mercedes Susana Carranza Patiño

2016-10-01

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 (DCA. 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.

A survey of Australian oysters for the presence of human noroviruses.

Science.gov (United States)

Brake, Felicity; Ross, Tom; Holds, Geoffrey; Kiermeier, Andreas; McLeod, Catherine

2014-12-01

Impending international policies for norovirus in oysters and the lack of Australian data suggested there was a need to undertake a national survey of norovirus in oysters. Two geographically distinct oyster-growing areas from each of three Australian states were sampled on 4 occasions during 2010 and 2011. The sites selected were considered by state shellfish authorities to be the most compromised with respect to the potential for human faecal contamination as identified by shoreline surveys. The oysters were tested for norovirus GI, GII and Escherichia coli. Norovirus GII was detected in two of 120 (1.7%) samples and norovirus GI was not detected. One of the norovirus positive samples was cloned and sequenced as GII.3. Five of 120 (4.2%) samples were found to have more than the guidance concentration of 230 E. coli per 100 g of shellfish but these samples did not contain detectable concentrations of norovirus. The apparently low prevalence of norovirus in oysters from Australian growing areas supports epidemiological data that suggests norovirus contamination of Australian oysters is rare. The results from this study emphasise the need for future norovirus control measures for shellfish to be commensurate with the risk associated with the growing area. Copyright © 2014 Elsevier Ltd. All rights reserved.

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.

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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

Descripción de un brote epidémico de malaria en una comunidad indígena asentada en la zona urbana de Armenia, Colombia, 2012

Directory of Open Access Journals (Sweden)

Liliana Quintero

2015-03-01

Conclusiones. Se reportó el primer brote autóctono de malaria por P.vivax en Armenia, asociado con un asentamiento subnormal en una comunidad indígena y se constató cómo en los márgenes del río Quindío se presentan las condiciones eco-epidemiológicas que permiten el ciclo de reproducción del mosquito vector de la malaria.

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.

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.

INDUCCIÓN DE CRECIMIENTO LATERAL EN NOGAL PECANERO (Carya illinoensis K. Koch. MEDIANTE DESPUNTE DE BROTES EN PRIMAVERA

Directory of Open Access Journals (Sweden)

J. G. Arreola-Ávila

2010-01-01

Full Text Available El nogal pecanero en desarrollo produce brotes apicales vigorosos limitando la inducción y desarrollo de brotes laterales, característica que retrasa la etapa productiva del árbol y estimula un desarrollo considerable de la copa con el consecuente problema de sombreo entre árboles, particularmente en huertas establecidas en altas densidades. Este estudio se realizó con el objetivo de evaluar el efecto que tiene la poda de despunte en verde, sobre la reducción del crecimiento de brotes apicales y la generación de brotación lateral, aspectos necesarios para limitar el desarrollo excesivo de la copa de nogales juveniles. De una huerta establecida en alta densidad en Viesca, Coahuila, se seleccionaron árboles de nogal pecanero de cinco años de edad. En la primavera del 2007 se realizaron tres tratamientos que consistieron en despunte en verde a 5, 10 y 15 yemas formadas, sobre brotes en pleno crecimiento activo, se incluyó un testigo sin despuntar. El despunte en verde, a 5 yemas desarrolladas, incrementó el porcentaje de rebrotes laterales en un 55 %. Mientras que en los tratamientos de despunte a 10 y 15 yemas se observaron incrementos de 53 y 50 %, respectivamente. Los tratamientos causaron una disminución en la longitud, número de hojas y área foliar de los nuevos brotes desarrollados (rebrotes en comparación con el testigo.

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

OpenAIRE

Luna Sánchez Antonio

1997-01-01

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 ...

Development of rhabdomyolysis in a child after norovirus gastroenteritis.

Science.gov (United States)

Nishio, Tomohiro; Yonetani, Ryoko; Ito, Eisuke; Yoneta, Makiko; Maruo, Yoshihiro; Yoshida, Tokiko; Sugimoto, Tohru

2016-11-04

In children, the most significant cause of rhabdomyolysis or muscle breakdown is viral infection. However, there are no reports that norovirus, a gastroenteric virus that commonly infects children, specifically causes rhabdomyolysis. Here, we report the first pediatric case of norovirus-associated rhabdomyolysis. The patient, a 2-year-old boy with fever, diarrhea, and vomiting, was referred to our hospital with dysstasia and transaminitis. He was diagnosed with rhabdomyolysis. Additionally, norovirus genogroup GII was detected from stool samples by real-time quantitative reverse transcription Polymerase Chain Reaction, and thereafter, the norovirus GII.4 variant was identified. However, the association between rhabdomyolysis and the isolated norovirus variant was not clarified. After treatment the patient recovered without renal failure or disseminated intravascular coagulation. Rhabdomyolysis is a disease for which there is a need for early detection and treatment. If abnormal posture or muscle weakness is observed during the course of gastroenteritis, blood and urinary tests should be performed to rule out rhabdomyolysis.

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. Copyright © 2012 Elsevier Ltd. All rights reserved.

Norovirus Genotype Profiles Associated with Foodborne Transmission, 1999??"2012

OpenAIRE

Verhoef, Linda; Hewitt, Joanne; Barclay, Leslie; Ahmed, Sharia; Lake, Rob; Hall, Aron J.; Lopman, Ben; Kroneman, Annelies; Vennema, Harry; VinjA(c), Jan; Koopmans, 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 norovirus transmission and genotyping information from multiple international outbreak surveillance systems (Noronet, CaliciNet, EpiSurv) and from a systematic review of peer-reviewed literature. The pr...

High Hand Contamination Rates During Norovirus Outbreaks in Long-Term Care Facilities.

Science.gov (United States)

Park, Geun Woo; Williamson, Keenan J; DeBess, Emilio; Cieslak, Paul R; Gregoricus, Nicole; De Nardo, Elizabeth; Fricker, Christopher; Costantini, Verónica; Vinjé, Jan

2018-02-01

We examined norovirus contamination on hands of ill patients during 12 norovirus outbreaks in 12 long-term care facilities (LTCFs). The higher frequency and norovirus titers on hands of residents compared to hands of heathcare workers highlights the importance of adhering to appropriate hand hygiene practices during norovirus outbreaks in LTCFs. Infect Control Hosp Epidemiol 2018;39:219-221.

Norovirus Prevention (A Cup of Health with CDC)

Centers for Disease Control (CDC) Podcasts

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.

High pressure processing inactivates human norovirus within oysters

Science.gov (United States)

Consumption of raw bivalve mollusks can result in norovirus infection. One potential intervention for virus-contaminated shellfish is high pressure processing (HPP). Currently HPP is known to inactivate Vibrio bacteria, hepatitis A virus, and murine norovirus within oysters. To evaluate the potentia...

Desarrollo floral del aguacate 'hass' en clima semicálido. Parte I. Influencia de la carga de fruto y edad de los brotes

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S. Salazar-García

2007-01-01

1,200 m en la que se ubicaron los huertos. El proceso completo de desarrollo floral desde S-1 (yema cerrada hasta S-11 (antesis en yemas apicales de brotes del flujo de invierno requirió de 367 a 371 días, mientras que los brotes del flujo de verano necesitaron 225 días. La edad de los brotes (invierno o verano no influyó en la fecha de antesis, que ocurrió en febrero.

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.

Inactivation of human norovirus using chemical sanitizers.

Science.gov (United States)

Kingsley, David H; Vincent, Emily M; Meade, Gloria K; Watson, Clytrice L; Fan, Xuetong

2014-02-03

The porcine gastric mucin binding magnetic bead (PGM-MB) assay was used to evaluate the ability of chlorine, chlorine dioxide, peroxyacetic acid, hydrogen peroxide, and trisodium phosphate to inactivate human norovirus within 10% stool filtrate. One-minute free chlorine treatments at concentrations of 33 and 189 ppm reduced virus binding in the PGM-MB assay by 1.48 and 4.14 log₁₀, respectively, suggesting that chlorine is an efficient sanitizer for inactivation of human norovirus (HuNoV). Five minute treatments with 5% trisodium phosphate (pH~12) reduced HuNoV binding by 1.6 log₁₀, suggesting that TSP, or some other high pH buffer, could be used to treat food and food contact surfaces to reduce HuNoV. One minute treatments with 350 ppm chlorine dioxide dissolved in water did not reduce PGM-MB binding, suggesting that the sanitizer may not be suitable for HuNoV inactivation in liquid form. However a 60-min treatment with 350 ppm chlorine dioxide did reduce human norovirus by 2.8 log₁₀, indicating that chlorine dioxide had some, albeit limited, activity against HuNoV. Results also suggest that peroxyacetic acid has limited effectiveness against human norovirus, since 1-min treatments with up to 195 ppm reduced human norovirus binding by chlorine (sodium hypochlorite) as a HuNoV disinfectant wherever possible. Copyright © 2013. Published by Elsevier B.V.

Brote de legionelosis asociado a un balneario

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I. Santa Marina Rodríguez

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.

[Comparison of two nucleic acid extraction methods for norovirus in oysters].

Science.gov (United States)

Yuan, Qiao; Li, Hui; Deng, Xiaoling; Mo, Yanling; Fang, Ling; Ke, Changwen

2013-04-01

To explore a convenient and effective method for norovirus nucleic acid extraction from oysters suitable for long-term viral surveillance. Two methods, namely method A (glycine washing and polyethylene glycol precipitation of the virus followed by silica gel centrifugal column) and method B (protease K digestion followed by application of paramagnetic silicon) were compared for their performance in norovirus nucleic acid extraction from oysters. Real-time RT-PCR was used to detect norovirus in naturally infected oysters and in oysters with induced infection. The two methods yielded comparable positive detection rates for the samples, but the recovery rate of the virus was higher with method B than with method A. Method B is a more convenient and rapid method for norovirus nucleic acid extraction from oysters and suitable for long-term surveillance of norovirus.

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. Copyright © 2015 Elsevier B.V. All rights reserved.

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

Non-thermal inactivation of Noroviruses in food

Science.gov (United States)

Velebit, B.; Petronijević, R.; Bošković, T.

2017-09-01

An increased incidence of foodborne illnesses caused by Norovirus and consumer demand for fresh, convenient, and safe foods have prompted research into alternative antiviral processing technologies. Chlorine dioxide, UV treatment and thermal processing are standard antinoroviral technologies that have been employed for a while; however, they tend to be non-effective in modern processing due to residue concerns (ClO2), shadowing effects (UV) and low-energy efficiency (heat treatment). Alternative technologies have been validated such as ozone treatment, high pressure processing and pulse electric fields. Although these techniques are promising, none of them individually can deem food free of Norovirus. Further research on the effects on Norovirus in various food matrices is required. Good manufacturing practices and proper sanitation procedures remain the “gold” safety tools in food business.

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.

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

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

An outbreak of multiple norovirus strains on a cruise ship in China, 2014.

Science.gov (United States)

Wang, X; Yong, W; Shi, L; Qiao, M; He, M; Zhang, H; Guo, B; Xie, G; Zhang, M; Jin, M; Ding, J

2016-01-01

To determine the cause of an outbreak of acute gastroenteritis that occurred on a cruise ship sailing along the Yangzi River from Chongqing to Nanjing, China. Noroviruses were identified by reverse transcription-PCR (RT-PCR) in rectal swabs from 34 of 54 subjects tested (63·0%). Sequencing and genotyping showed that noroviruses of up to seven different genotypes circulated in this outbreak: noroviruses GI.1, GI.2, GI.3, GI.4, GI.8, GI.9 and an uncommon strain GII.17. Common genotypes were not identified in this event. None of the food or water samples were tested positive for noroviruses. We suspected that it was a point-source infection due to contaminated water or food harvested from contaminated water, taking account of the co-existence of diverse norovirus genotypes. In this study, we presented the molecular investigation of a norovirus outbreak on a cruise in China. We revealed that the outbreak was caused by several different norovirus genotypes and analysed the possible source of infection as well, thus facilitating the evaluation of epidemiological issues regarding noroviruses in this area. © 2015 The Society for Applied Microbiology.

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.

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.

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

OpenAIRE

Jaime A. del Río; Carmen M. Jurado; Fernando Arango

2009-01-01

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 ...

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.

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

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

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. PMID:26598569

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. © The American Society of Tropical Medicine and Hygiene.

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.

Innate Susceptibility to Norovirus Infections Influenced by FUT2 Genotype in a United States Pediatric Population

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Currier, Rebecca L.; Payne, Daniel C.; Staat, Mary A.; Selvarangan, Rangaraj; Shirley, S. Hannah; Halasa, Natasha; Boom, Julie A.; Englund, Janet A.; Szilagyi, Peter G.; Harrison, Christopher J.; Klein, Eileen J.; Weinberg, Geoffrey A.; Wikswo, Mary E.; Parashar, Umesh; Vinjé, Jan; Morrow, Ardythe L.

2015-01-01

Background. Norovirus is a leading cause of acute gastroenteritis (AGE). Noroviruses bind to gut histo-blood group antigens (HBGAs), but only 70%–80% of individuals have a functional copy of the FUT2 (“secretor”) gene required for gut HBGA expression; these individuals are known as “secretors.” Susceptibility to some noroviruses depends on FUT2 secretor status, but the population impact of this association is not established. Methods. From December 2011 to November 2012, active AGE surveillance was performed at 6 geographically diverse pediatric sites in the United States. Case patients aged <5 years were recruited from emergency departments and inpatient units; age-matched healthy controls were recruited at well-child visits. Salivary DNA was collected to determine secretor status and genetic ancestry. Stool was tested for norovirus by real-time reverse transcription polymerase chain reaction. Norovirus genotype was then determined by sequencing. Results. Norovirus was detected in 302 of 1465 (21%) AGE cases and 52 of 826 (6%) healthy controls. Norovirus AGE cases were 2.8-fold more likely than norovirus-negative controls to be secretors (P < .001) in a logistic regression model adjusted for ancestry, age, site, and health insurance. Secretors comprised all 155 cases and 21 asymptomatic infections with the most prevalent norovirus, GII.4. Control children of Meso-American ancestry were more likely than children of European or African ancestry to be secretors (96% vs 74%; P < .001). Conclusions. FUT2 status is associated with norovirus infection and varies by ancestry. GII.4 norovirus exclusively infected secretors. These findings are important to norovirus vaccine trials and design of agents that may block norovirus-HBGA binding. PMID:25744498

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.

Norovirus genotype profiles associated with foodborne transmission, 1999–2012

NARCIS (Netherlands)

L. Verhoef; J. Hewitt (Joanne); L. Barclay (Leslie); S.M. Ahmed (Sharia); 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

Comparison of norovirus RNA levels in outbreak-related oysters with background environmental levels.

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Lowther, James A; Gustar, Nicole E; Hartnell, Rachel E; Lees, David N

2012-02-01

Norovirus is the principal agent of bivalve shellfish-associated gastroenteric illness worldwide. Numerous studies using PCR have demonstrated norovirus contamination in a significant proportion of both oyster and other bivalve shellfish production areas and ready-to-eat products. By comparison, the number of epidemiologically confirmed shellfish-associated outbreaks is relatively low. This suggests that factors other than the simple presence or absence of virus RNA are important contributors to the amount of illness reported. This study compares norovirus RNA levels in oyster samples strongly linked to norovirus or norovirus-type illness with the levels typically found in commercial production areas (non-outbreak-related samples). A statistically significant difference between norovirus levels in the two sets of samples was observed. The geometric mean of the levels in outbreak samples (1,048 copies per g) was almost one order of magnitude higher than for positive non-outbreak-related samples (121 copies per g). Further, while none of the outbreak-related samples contained fewer than 152 copies per g, the majority of positive results for non-outbreak-related samples was below this level. These observations support the concept of a dose-response for norovirus RNA levels in shellfish and could help inform the establishment of threshold criteria for risk management.

Temperature-dependent persistence of human norovirus within oysters (Crassotrea virginica)

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This study characterizes the persistence of human norovirus in Eastern oysters (Crassostrea virginica) held at different seawater temperatures. Oysters were contaminated with human norovirus GI.1 (Norwalk strain 8fIIa) by exposing them to virus contaminated water at 15 degrees C, and subsequently ho...

Interferon lambda (IFN-λ) efficiently blocks norovirus transmission in a mouse model.

Science.gov (United States)

Rocha-Pereira, Joana; Jacobs, Sophie; Noppen, Sam; Verbeken, Eric; Michiels, Thomas; Neyts, Johan

2018-01-01

Human noroviruses are highly efficient in person to person transmission thus associated with explosive outbreaks of acute gastroenteritis. Outbreak control is limited to disinfection and isolation measures. Strategies to control the spread of noroviruses should be developed and models to study norovirus transmission will greatly facilitate this. Here, a mouse-to-mouse transmission model, in which mice develop acute murine norovirus (MNV)-induced diarrhea, was used to explore the role of interferon lambda (IFN-λ) in the control of a norovirus infection. Sentinel AG129 mice [deficient in IFN-α/β and IFN-γ receptors] that were co-housed with MNV-infected mice shedding high amounts of virus in their stool, developed a MNV-infection with associated diarrhea. Inoculation of such sentinel mice with an IFN-λ expression plasmid resulted in the production of circulating IFN-λ and upregulation of the expression of IFN-stimulated genes (ISGs) of the gut. Injection of the IFN-λ-expressing plasmid to sentinels prevents MNV-induced disease upon exposure to MNV-infected mice, as well as MNV replication in the small intestine, the associated signs of inflammation and the mounting of a specific IgG-based immune response. This demonstrates that IFN-λ can alone mediate protection against transmission of norovirus. The development of a simple delivery method for IFN-λ could be explored as a strategy to control norovirus outbreaks and protect vulnerable populations such as the elderly and immunocompromised. Copyright © 2017. Published by Elsevier B.V.

Airborne or Fomite Transmission for Norovirus? A Case Study Revisited.

Science.gov (United States)

Xiao, Shenglan; Tang, Julian W; Li, Yuguo

2017-12-14

Norovirus infection, a highly prevalent condition associated with a high rate of morbidity, comprises a significant health issue. Although norovirus transmission mainly occurs via the fecal-oral and vomit-oral routes, airborne transmission has been proposed in recent decades. This paper re-examines a previously described norovirus outbreak in a hotel restaurant wherein airborne transmission was originally inferred. Specifically, the original evidence that suggested airborne transmission was re-analyzed by exploring an alternative hypothesis: could this outbreak instead have occurred via fomite transmission? This re-analysis was based on whether fomite transmission could have yielded similar attack rate distribution patterns. Seven representative serving pathways used by waiters were considered, and the infection risk distributions of the alternative fomite transmission routes were predicted using a multi-agent model. These distributions were compared to the reported attack rate distribution in the original study using a least square methods approach. The results show that with some reasonable assumptions of human behavior patterns and parameter values, the attack rate distribution corresponded well with that of the infection risk via the fomite route. This finding offers an alternative interpretation of the transmission routes that underlay this particular norovirus outbreak and an important consideration in the development of infection control guidelines and the investigation of similar norovirus outbreaks in future.

Food-borne norovirus-outbreak at a military base, Germany, 2009.

Science.gov (United States)

Wadl, Maria; Scherer, Kathrin; Nielsen, Stine; Diedrich, Sabine; Ellerbroek, Lüppo; Frank, Christina; Gatzer, Renate; Hoehne, Marina; Johne, Reimar; Klein, Günter; Koch, Judith; Schulenburg, Jörg; Thielbein, Uta; Stark, Klaus; Bernard, Helen

2010-02-17

Norovirus is often transmitted from person-to-person. Transmission may also be food-borne, but only few norovirus outbreak investigations have identified food items as likely vehicles of norovirus transmission through an analytical epidemiological study.During 7-9 January, 2009, 36 persons at a military base in Germany fell ill with acute gastroenteritis. Food from the military base's canteen was suspected as vehicle of infection, norovirus as the pathogen causing the illnesses. An investigation was initiated to describe the outbreak's extent, to verify the pathogen, and to identify modes of transmission and source of infection to prevent further cases. For descriptive analysis, ill persons were defined as members of the military base with acute onset of diarrhoea or vomiting between 24 December 2008, and 3 February 2009, without detection of a pathogen other than norovirus in stools. We conducted a retrospective cohort study within the headquarters company. Cases were military base members with onset of diarrhoea or vomiting during 5-9 January. We collected information on demographics, food items eaten at the canteen and contact to ill persons or vomit, using a self-administered questionnaire. We compared attack rates (AR) in exposed and unexposed persons, using bivariable and multivariable logistic regression modelling. Stool specimens of ill persons and canteen employees, canteen food served during 5-7 January and environmental swabs were investigated by laboratory analysis. Overall, 101/815 (AR 12.4%) persons fell ill between 24 December 2008 and 3 February 2009. None were canteen employees. Most persons (n = 49) had disease onset during 7-9 January. Ill persons were a median of 22 years old, 92.9% were male. The response for the cohort study was 178/274 (72.1%). Of 27 cases (AR 15.2%), 25 had eaten at the canteen and 21 had consumed salad. Salad consumption on 6 January (aOR: 8.1; 95%CI: 1.5-45.4) and 7 January (aOR: 15.7; 95%CI: 2.2-74.1) were independently

Recurring norovirus transmission on an airplane.

Science.gov (United States)

Thornley, Craig N; Emslie, Nicola A; Sprott, Tim W; Greening, Gail E; Rapana, Jackie P

2011-09-01

Previously reported outbreaks of norovirus gastroenteritis associated with aircraft have been limited to transmission during a single flight sector. During October 2009, an outbreak of diarrhea and vomiting occurred among different groups of flight attendants who had worked on separate flight sectors on the same airplane. We investigated the cause of the outbreak and whether the illnesses were attributable to work on the airplane. Information was obtained from flight attendants on demographic characteristics, symptoms, and possible transmission risk factors. Case patients were defined as flight attendants with diarrhea or vomiting airplane during 13-18 October 2009. Stool samples were tested for norovirus RNA. A passenger had vomited on the Boeing 777-200 airplane on the 13 October flight sector. Sixty-three (82%) of 77 flight attendants who worked on the airplane during 13-18 October provided information, and 27 (43%) met the case definition. The attack rate among flight attendants decreased significantly over successive flight sectors from 13 October onward (P airplane during successive flight sectors. Airlines should make provision for adequate disinfection of airplanes with use of products effective against norovirus and other common infectious agents after vomiting has occurred.

Nanobodies targeting norovirus capsid reveal functional epitopes and potential mechanisms of neutralization.

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Anna D Koromyslova

2017-11-01

Full Text Available Norovirus is the leading cause of gastroenteritis worldwide. Despite recent developments in norovirus propagation in cell culture, these viruses are still challenging to grow routinely. Moreover, little is known on how norovirus infects the host cells, except that histo-blood group antigens (HBGAs are important binding factors for infection and cell entry. Antibodies that bind at the HBGA pocket and block attachment to HBGAs are believed to neutralize the virus. However, additional neutralization epitopes elsewhere on the capsid likely exist and impeding the intrinsic structural dynamics of the capsid could be equally important. In the current study, we investigated a panel of Nanobodies in order to probe functional epitopes that could trigger capsid rearrangement and/ or interfere with HBGA binding interactions. The precise binding sites of six Nanobodies (Nano-4, Nano-14, Nano-26, Nano-27, Nano-32, and Nano-42 were identified using X-ray crystallography. We showed that these Nanobodies bound on the top, side, and bottom of the norovirus protruding domain. The impact of Nanobody binding on norovirus capsid morphology was analyzed using electron microscopy and dynamic light scattering. We discovered that distinct Nanobody epitopes were associated with varied changes in particle structural integrity and assembly. Interestingly, certain Nanobody-induced capsid morphological changes lead to the capsid protein degradation and viral RNA exposure. Moreover, Nanobodies employed multiple inhibition mechanisms to prevent norovirus attachment to HBGAs, which included steric obstruction (Nano-14, allosteric interference (Nano-32, and violation of normal capsid morphology (Nano-26 and Nano-85. Finally, we showed that two Nanobodies (Nano-26 and Nano-85 not only compromised capsid integrity and inhibited VLPs attachment to HBGAs, but also recognized a broad panel of norovirus genotypes with high affinities. Consequently, Nano-26 and Nano-85 have a great

Nanobodies targeting norovirus capsid reveal functional epitopes and potential mechanisms of neutralization

Science.gov (United States)

2017-01-01

Norovirus is the leading cause of gastroenteritis worldwide. Despite recent developments in norovirus propagation in cell culture, these viruses are still challenging to grow routinely. Moreover, little is known on how norovirus infects the host cells, except that histo-blood group antigens (HBGAs) are important binding factors for infection and cell entry. Antibodies that bind at the HBGA pocket and block attachment to HBGAs are believed to neutralize the virus. However, additional neutralization epitopes elsewhere on the capsid likely exist and impeding the intrinsic structural dynamics of the capsid could be equally important. In the current study, we investigated a panel of Nanobodies in order to probe functional epitopes that could trigger capsid rearrangement and/ or interfere with HBGA binding interactions. The precise binding sites of six Nanobodies (Nano-4, Nano-14, Nano-26, Nano-27, Nano-32, and Nano-42) were identified using X-ray crystallography. We showed that these Nanobodies bound on the top, side, and bottom of the norovirus protruding domain. The impact of Nanobody binding on norovirus capsid morphology was analyzed using electron microscopy and dynamic light scattering. We discovered that distinct Nanobody epitopes were associated with varied changes in particle structural integrity and assembly. Interestingly, certain Nanobody-induced capsid morphological changes lead to the capsid protein degradation and viral RNA exposure. Moreover, Nanobodies employed multiple inhibition mechanisms to prevent norovirus attachment to HBGAs, which included steric obstruction (Nano-14), allosteric interference (Nano-32), and violation of normal capsid morphology (Nano-26 and Nano-85). Finally, we showed that two Nanobodies (Nano-26 and Nano-85) not only compromised capsid integrity and inhibited VLPs attachment to HBGAs, but also recognized a broad panel of norovirus genotypes with high affinities. Consequently, Nano-26 and Nano-85 have a great potential to

Efecto de la densidad de explantes y el volumen de medio de cultivo sobre la multiplicación in vitro de arándano (Vaccinium corymbosum L. variedades Brigitta y Legacy

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Mario Rodríguez Beraud

2015-01-01

Full Text Available El objetivo fue evaluar la multiplicación in vitro de dos variedades de arándano (Vaccinium corymbosum L., “Brigitta” y “Legacy”, en respuesta a cinco densidades de explantes (5, 10, 15, 20 y 25 y cuatro volúmenes de medio (10, 20, 30 y 40 mL utilizando para ambas variedades el medio WPM (Woody Plant Medium en un diseño completamente al azar con 20 tratamientos y 12 repeticiones por tratamiento. Transcurrido 45 días se evaluó: altura de brote, número de brotes/explante, número de nudos/brote y número de brotes/frasco. Brigitta obtuvo la mayor altura del brote en tratamientos con densidades y volúmenes elevados, mientras que Legacy obtuvo el mayor promedio de altura del brote con densidades intermedias y volúmenes elevados. En cuanto al número de brotes/explante, el volumen de medio no influyó en la variedad Brigitta, en cambio, altas densidades la afectaron significativamente, mientras que en Legacy el máximo número de brotes se alcanzó con densidades bajas y volúmenes intermedios. En relación al número de nudos por explante Brigitta obtuvo los valores más bajos comparados con Legacy, pero en ambas variedades se produjo una disminución del número de nudos con menores volúmenes de medio. Para el número de brotes por frasco Brigitta obtuvo las mayores respuestas con densidades elevadas, superando los 40 brotes por frasco. En cambio, en Legacy el resultado máximo se obtuvo con la densidad 25 explantes en 30 mL de medio. Por lo tanto, se concluye que ambas variedades fueron influenciadas tanto por el volumen del medio como la densidad de explantes.

Atomic structure of the murine norovirus protruding domain and sCD300lf receptor complex.

Science.gov (United States)

Kilic, Turgay; Koromyslova, Anna; Malak, Virginie; Hansman, Grant S

2018-03-21

Human noroviruses are the leading cause of acute gastroenteritis in human. Noroviruses also infect animals such as cow, mice, cat, and dog. How noroviruses bind and enter host cells is still incompletely understood. Recently, the type I transmembrane protein CD300lf was recently identified as the murine norovirus receptor, yet it is unclear how the virus capsid and receptor interact at the molecular level. In this study, we determined the X-ray crystal structure of the soluble CD300lf (sCD300lf) and murine norovirus capsid-protruding domain complex at 2.05 Å resolution. We found that the sCD300lf binding site is located on the topside of the protruding domain and involves a network of hydrophilic and hydrophobic interactions. The sCD300lf locked nicely into a complementary cavity on the protruding domain that is additionally coordinated with a positive surface charge on the sCD300lf and a negative surface charge on the protruding domain. Five of six protruding domain residues interacting with sCD300lf were maintained between different murine norovirus strains, suggesting that the sCD300lf was capable of binding to a highly conserved pocket. Moreover, a sequence alignment with other CD300 paralogs showed that the sCD300lf interacting residues were partially conserved in CD300ld, but variable in other CD300 family members, consistent with previously reported infection selectivity. Overall, these data provide insights into how a norovirus engages a protein receptor and will be important for a better understanding of selective recognition and norovirus attachment and entry mechanisms. IMPORTANCE Noroviruses exhibit exquisite host-range specificity due to species-specific interactions between the norovirus capsid protein and host molecules. Given this strict host-range restriction it has been unclear how the viruses are maintained within a species between relatively sporadic epidemics. While much data demonstrates that noroviruses can interact with carbohydrates

Strain-Specific Virolysis Patterns of Human Noroviruses in Response to Alcohols.

Science.gov (United States)

Park, Geun Woo; Collins, Nikail; Barclay, Leslie; Hu, Liya; Prasad, B V Venkataram; Lopman, Benjamin A; Vinjé, Jan

2016-01-01

Alcohol-based hand sanitizers are widely used to disinfect hands to prevent the spread of pathogens including noroviruses. Alcohols inactivate norovirus by destruction of the viral capsid, resulting in the leakage of viral RNA (virolysis). Since conflicting results have been reported on the susceptibility of human noroviruses against alcohols, we exposed a panel of 30 human norovirus strains (14 GI and 16 GII strains) to different concentrations (50%, 70%, 90%) of ethanol and isopropanol and tested the viral RNA titer by RT-qPCR. Viral RNA titers of 10 (71.4%), 14 (100%), 3 (21.4%) and 7 (50%) of the 14 GI strains were reduced by > 1 log10 RNA copies/ml after exposure to 70% and 90% ethanol, and 70% and 90% isopropanol, respectively. RNA titers of 6 of the 7 non-GII 4 strains remained unaffected after alcohol exposure. Compared to GII strains, GI strains were more susceptible to ethanol than to isopropanol. At 90%, both alcohols reduced RNA titers of 8 of the 9 GII.4 strains by ≥ 1 log10 RNA copies/ml. After exposure to 70% ethanol, RNA titers of GII.4 Den Haag and Sydney strains decreased by ≥ 1.9 log10, whereas RNA reductions for GII.4 New Orleans strains were alcohol susceptibility patterns between different norovirus genotypes vary widely and that virolysis data for a single strain or genotype are not representative for all noroviruses.

Vital Signs-Preventing Norovirus Outbreaks

Centers for Disease Control (CDC) Podcasts

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.

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.

Norovirus Genetic Diversity – from within patient viral evolution to global distribution : Genetische diversiteit van norovirus – van virale evolutie binnen patiënten tot wereldwijde verspreiding

NARCIS (Netherlands)

J. van Beek (Janko)

2018-01-01

textabstractNoroviruses belong to the family of Caliciviridae and cause acute gastroenteritis. The genetic diversity within the genus Norovirus is extremely large and novel genotypes, recombinants within and between genotypes, and antigenic drift variants are regularly discovered. The distribution

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

Food-borne norovirus-outbreak at a military base, Germany, 2009

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Hoehne Marina

2010-02-01

Full Text Available Abstract Background Norovirus is often transmitted from person-to-person. Transmission may also be food-borne, but only few norovirus outbreak investigations have identified food items as likely vehicles of norovirus transmission through an analytical epidemiological study. During 7-9 January, 2009, 36 persons at a military base in Germany fell ill with acute gastroenteritis. Food from the military base's canteen was suspected as vehicle of infection, norovirus as the pathogen causing the illnesses. An investigation was initiated to describe the outbreak's extent, to verify the pathogen, and to identify modes of transmission and source of infection to prevent further cases. Methods For descriptive analysis, ill persons were defined as members of the military base with acute onset of diarrhoea or vomiting between 24 December 2008, and 3 February 2009, without detection of a pathogen other than norovirus in stools. We conducted a retrospective cohort study within the headquarters company. Cases were military base members with onset of diarrhoea or vomiting during 5-9 January. We collected information on demographics, food items eaten at the canteen and contact to ill persons or vomit, using a self-administered questionnaire. We compared attack rates (AR in exposed and unexposed persons, using bivariable and multivariable logistic regression modelling. Stool specimens of ill persons and canteen employees, canteen food served during 5-7 January and environmental swabs were investigated by laboratory analysis. Results Overall, 101/815 (AR 12.4% persons fell ill between 24 December 2008 and 3 February 2009. None were canteen employees. Most persons (n = 49 had disease onset during 7-9 January. Ill persons were a median of 22 years old, 92.9% were male. The response for the cohort study was 178/274 (72.1%. Of 27 cases (AR 15.2%, 25 had eaten at the canteen and 21 had consumed salad. Salad consumption on 6 January (aOR: 8.1; 95%CI: 1.5-45.4 and 7

Preventing Norovirus Outbreaks PSA (:60)

Centers for Disease Control (CDC) Podcasts

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.

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

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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.

promisorios de Myrciaria dubia (H.B.K. “camu camu” para propagación vegetativa por acodo aéreo

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Jiang Oliver Liao Torres

2012-01-01

Full Text Available El objetivo del presente trabajo fue evaluar el efecto de la ubicación y diámetro de la rama en tres genotipospromisorios de camu camu utilizando la técnica del acodo aéreo sobre el enraizamiento y brotación. Lasplantas madres fueron acodadas, posteriormente las ramas enraizadas se trasplantaron siguiendo el diseño deBloques Completos al Azar, con tres repeticiones. A los 3 meses del trasplante se realizó la evaluación de lasvariables, encontrando los mejores promedios para el Número de raíces al Tercio medio, Diámetro grueso,Genotipo MD-015 y al Tercio superior, Diámetro grueso, Genotipo MD-015 con 28.67 y 28.33 raíces,respectivamente; en la variable Longitud de raíces el Tercio superior, Diámetro grueso, Genotipo MD-015mostró los mejores resultados con 15.27 cm. Con respecto al Número de brotes el Tercio Superior, DiámetroGrueso, Genotipo MD-014 y el Tercio superior, Diámetro grueso, Genotipo MD-015 alcanzaron los mejoresresultados con 13.00 y 12.67 brotes, respectivamente; en la Longitud de brotes, el mejor tratamiento fue elTercio superior, Diámetro grueso, Genotipo MD-015 con 30.73 cm; finalmente en la variable Número dehojas/brote sobresalieron el Tercio superior, Diámetro grueso, Genotipo MD-014 y Tercio superior, Diámetrogrueso, Genotipo MD-015 con 15.10 y 14.83 hojas por brote, respectivamente. Los resultados permitieronidentificar al Tercio superior, Diámetro grueso, Genotipo MD-015 como los mejores en cuanto a la capacidadde enraizamiento y brotación.

[Norovirus outbreaks in hospitals and nursing homes in Catalonia, Spain].

Science.gov (United States)

Godoy, Pere; Domínguez, Angela; Alvarez, Josep; Camps, Neus; Barrabeig, Irene; Bartolomé, Rosa; Sala, María Rosa; Ferre, Dolors; Pañella, Helena; Torres, Joan; Minguell, Sofía; Alsedà, Miquel; Pumares, Analía

2009-01-01

The low infectious dose and multiple transmission routes favour the appearance of norovirus outbreaks. The objective of this study was to compare the incidence of norovirus outbreaks in hospitals and nursing homes in Catalonia. A descriptive study of norovirus outbreaks between 15/10/2004 and 30/10/2005 was carried out. An epidemiological survey was completed for each outbreak. Norovirus in clinical samples was determined by PCR techniques. The incidence in each centre and the annual incidence of outbreaks by centre were calculated. Differences were calculated using the chi-square test and the Student's t test, taking a p value of > 0.05 as significant. Seventeen outbreaks (6 in hospitals and 11 in nursing homes) were detected. The global attack rate was 33.4% (652/1951) and was slightly higher in nursing homes (35.2%) than in hospitals (31.4%). A total of 94.1% (16/17) of outbreaks were caused by person-to-person transmission and only 5.9% (1/17) by foods. The mean number of days between the first and last case was 11.4 (SD = 6.9). The mean duration of symptoms was 2.39 days (SD=1.6), and was higher hospitals, 2.63 (SD=1.7), than in nursing homes, 1.97 (SD=1.7) (p < 0.0001). Norovirus is responsible for a large number of outbreaks due to person-to-person transmission. Control should be standardized to reduce the number and duration of outbreaks.

Norovirus Infection in Older Adults: Epidemiology, Risk Factors, and Opportunities for Prevention and Control.

Science.gov (United States)

Cardemil, Cristina V; Parashar, Umesh D; Hall, Aron J

2017-12-01

Norovirus is the leading cause of acute gastroenteritis. In older adults, it is responsible for an estimated 3.7 million illnesses; 320,000 outpatient visits; 69,000 emergency department visits; 39,000 hospitalizations; and 960 deaths annually in the United States. Older adults are particularly at risk for severe outcomes, including prolonged symptoms and death. Long-term care facilities and hospitals are the most common settings for norovirus outbreaks in developed countries. Diagnostic platforms are expanding. Several norovirus vaccines in clinical trials have the potential to reap benefits. This review summarizes current knowledge on norovirus infection in older adults. Published by Elsevier Inc.

Brote de parotiditis vírica en un colegio de Bizkaia en 2006

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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.

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

The major targets of acute norovirus infection are immune cells in the gut-associated lymphoid tissue.

Science.gov (United States)

Grau, Katrina R; Roth, Alexa N; Zhu, Shu; Hernandez, Abel; Colliou, Natacha; DiVita, Bayli B; Philip, Drake T; Riffe, Cara; Giasson, Benoit; Wallet, Shannon M; Mohamadzadeh, Mansour; Karst, Stephanie M

2017-12-01

Noroviruses are the leading cause of food-borne gastroenteritis outbreaks and childhood diarrhoea globally, estimated to be responsible for 200,000 deaths in children each year 1-4 . Thus, reducing norovirus-associated disease is a critical priority. Development of vaccines and therapeutics has been hindered by the limited understanding of basic norovirus pathogenesis and cell tropism. While macrophages, dendritic cells, B cells and stem-cell-derived enteroids can all support infection of certain noroviruses in vitro 5-7 , efforts to define in vivo norovirus cell tropism have generated conflicting results. Some studies detected infected intestinal immune cells 8-12 , other studies detected epithelial cells 13 , and still others detected immune and epithelial cells 14-16 . Major limitations of these studies are that they were performed on tissue sections from immunocompromised or germ-free hosts, chronically infected hosts where the timing of infection was unknown, or following non-biologically relevant inoculation routes. Here, we report that the dominant cellular targets of a murine norovirus inoculated orally into immunocompetent mice are macrophages, dendritic cells, B cells and T cells in the gut-associated lymphoid tissue. Importantly, we also demonstrate that a norovirus can infect T cells, a previously unrecognized target, in vitro. These findings represent the most extensive analyses to date of in vivo norovirus cell tropism in orally inoculated, immunocompetent hosts at the peak of acute infection and thus they significantly advance our basic understanding of norovirus pathogenesis.

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...

Reporting and Surveillance for Norovirus Outbreaks

Science.gov (United States)

... Vaccine Surveillance Network (NVSN) Foodborne Diseases Active Surveillance Network (FoodNet) National Outbreak Reporting System (NORS) Estimates of Foodborne Illness in the United States CDC's Vessel Sanitation Program CDC Feature: Surveillance for Norovirus Outbreaks Top ...

Molecular surveillance of norovirus, 2005-16 : an epidemiological analysis of data collected from the NoroNet network

NARCIS (Netherlands)

van Beek, Janko; de Graaf, Miranda; Al-Hello, Haider; Allen, David J; Ambert-Balay, Katia; Botteldoorn, Nadine; Brytting, Mia; Buesa, Javier; Cabrerizo, Maria; Chan, Martin; Cloak, Fiona; Di Bartolo, Ilaria; Guix, Susana; Hewitt, Joanne; Iritani, Nobuhiro; Jin, Miao; Johne, Reimar; Lederer, Ingeborg; Mans, Janet; Martella, Vito; Maunula, Leena; McAllister, Georgina; Niendorf, Sandra; Niesters, Hubert G; Podkolzin, Alexander T; Poljsak-Prijatelj, Mateja; Rasmussen, Lasse Dam; Reuter, Gábor; Tuite, Gráinne; Kroneman, Annelies; Vennema, Harry; Koopmans, Marion P G

BACKGROUND: The development of a vaccine for norovirus requires a detailed understanding of global genetic diversity of noroviruses. We analysed their epidemiology and diversity using surveillance data from the NoroNet network. METHODS: We included genetic sequences of norovirus specimens obtained

Human Norovirus and Its Surrogates Induce Plant Immune Response in Arabidopsis thaliana and Lactuca sativa.

Science.gov (United States)

Markland, Sarah M; Bais, Harsh; Kniel, Kalmia E

2017-08-01

Human norovirus is the leading cause of foodborne illness worldwide with the majority of outbreaks linked to fresh produce and leafy greens. It is essential that we thoroughly understand the type of relationship and interactions that take place between plants and human norovirus to better utilize control strategies to reduce transmission of norovirus in the field onto plants harvested for human consumption. In this study the expression of gene markers for the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways was measured and compared in romaine lettuce (Lactuca sativa) and Arabidopsis thaliana Col-0 plants that were inoculated with Murine Norovirus-1, Tulane Virus, human norovirus GII.4, or Hank's Balanced Salt Solution (control). Genes involving both the SA and JA pathways were expressed in both romaine lettuce and A. thaliana for all three viruses, as well as controls. Studies, including gene expression of SA- and JA-deficient A. thaliana mutant lines, suggest that the JA pathway is more likely involved in the plant immune response to human norovirus. This research provides the first pieces of information regarding how foodborne viruses interact with plants in the preharvest environment.

El Reglamento Sanitario Internacional, la enfermedad por el virus del Ébola y las enfermedades infecciosas emergentes en América Latina y el Caribe

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Marcos Espinal

Full Text Available RESUMEN La determinación por parte de la Organización Mundial de la Salud de que el brote de enfermedad por el virus del Ébola constituía un evento de salud pública de importancia internacional llevó a los países que no estaban afectados a aplicar medidas para prevenir y detectar la introducción del virus en sus territorios y para reaccionar frente a ella. El brote brindó la oportunidad de evaluar la aplicación operativa de las capacidades básicas del Reglamento Sanitario Internacional y la preparación de los sistemas de salud para hacer frente a un caso posible o confirmado de enfermedad por el virus del Ébola. Un marco rector de salud pública aplicado en los países de América Latina y el Caribe, que abarca autoevaluaciones preparatorias, visitas a los propios países y seguimiento, sugiere que esa región debe aumentar sus esfuerzos por consolidar y mantener los progresos en las capacidades básicas y en la preparación del sistema de salud para hacer frente a eventos de salud pública que tengan repercusiones a escala nacional o internacional.

[Waterborne outbreak of gastroenteritis caused by Norovirus transmitted through drinking water].

Science.gov (United States)

Godoy, P; Nuín, C; Alsedà, M; Llovet, T; Mazana, R; Domínguez, A

2006-10-01

The aim of this study was to conduct an investigation into an outbreak of waterborne disease caused by Norovirus due to the consumption of contaminated drinking water. The first week after the school summer holidays we detected an outbreak of gastroenteritis at a school in Borges Blanques (Lleida, Spain). A retrospective cohort study was carried out to investigate: water consumption and food (six items). We assessed RNA Norovirus by RT-PCR in 6 stool samples. The risk of gastroenteritis was assessed by applying adjusted risk ratio (RRa) analysis at 95% confidence intervals (CI). The overall attack rate was 45% (96/213). The main symptoms were: abdominal pain, 88.4% (84/95); nausea, 65.9% (62/94), and vomiting, 64.6% (62/96). The consumption of school drinking water was statistically associated with the disease (RRa: 2.8; 95% CI: 1.3-6.2). The school water tank was dirty, but this drinking water was qualified as potable. Six stool samples gave positive results for Norovirus. Norovirus caused this waterborne outbreak of gastroenteritis transmitted through treated drinking water. It should be obligatory to regularly clean school drinking water deposit tanks, especially after the summer holidays.

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

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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.

Sanitizer efficacy against murine norovirus, a surrogate for human norovirus, on stainless steel surfaces when using three application methods.

Science.gov (United States)

Bolton, Stephanie L; Kotwal, Grishma; Harrison, Mark A; Law, S Edward; Harrison, Judy A; Cannon, Jennifer L

2013-02-01

Human noroviruses are major etiologic agents of epidemic gastroenteritis. Outbreaks are often accompanied by contamination of environmental surfaces, but since these viruses cannot be routinely propagated in laboratory cultures, their response to surface disinfectants is predicted by using surrogates, such as murine norovirus 1 (MNV-1). This study compared the virucidal efficacies of various liquid treatments (three sanitizer liquids, 5% levulinic acid plus 2% SDS [LEV/SDS], 200 ppm chlorine, and an isopropanol-based quaternary ammonium compound [Alpet D2], and two control liquids, sterile tap water and sterile tap water plus 2% SDS) when delivered to MNV-1-inoculated stainless steel surfaces by conventional hydraulic or air-assisted, induction-charged (AAIC) electrostatic spraying or by wiping with impregnated towelettes. For the spray treatments, LEV/SDS proved effective when applied with hydraulic and AAIC electrostatic spraying, providing virus reductions of 2.71 and 1.66 log PFU/ml, respectively. Alpet D2 provided a 2.23-log PFU/ml reduction with hydraulic spraying, outperforming chlorine (1.16-log PFU/ml reduction). Chlorine and LEV/SDS were equally effective as wipes, reducing the viral load by 7.05 log PFU/ml. Controls reduced the viral load by 3 log PFU/ml with wiping. Results indicated that both sanitizer type and application methods should be carefully considered when choosing a surface disinfectant to best prevent and control environmental contamination by noroviruses.

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

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.

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.

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

Comparison of methods for detection of norovirus in oysters

DEFF Research Database (Denmark)

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

2007-01-01

a successful detection it is of great importance to remove the tissue inhibitors during the viral RNA extraction. To select the most efficient extraction procedure of oysters we have compared four protocols. A pool of digestive gland material from oyster samples was divided into 1.5 g portions and spiked...... with I 0-fold dilutions of human faecal samples containing norovirus genogroup II. The samples were tested on three different occasions using four different sample treatment protocols. The protocols were assessed with regard to their ability to recover viral RNA and detect norovirus in spiked oysters...

Bat Caliciviruses and Human Noroviruses Are Antigenically Similar and Have Overlapping Histo-Blood Group Antigen Binding Profiles.

Science.gov (United States)

Kocher, Jacob F; Lindesmith, Lisa C; Debbink, Kari; Beall, Anne; Mallory, Michael L; Yount, Boyd L; Graham, Rachel L; Huynh, Jeremy; Gates, J Edward; Donaldson, Eric F; Baric, Ralph S

2018-05-22

Emerging zoonotic viral diseases remain a challenge to global public health. Recent surveillance studies have implicated bats as potential reservoirs for a number of viral pathogens, including coronaviruses and Ebola viruses. Caliciviridae represent a major viral family contributing to emerging diseases in both human and animal populations and have been recently identified in bats. In this study, we blended metagenomics, phylogenetics, homology modeling, and in vitro assays to characterize two novel bat calicivirus (BtCalV) capsid sequences, corresponding to strain BtCalV/A10/USA/2009, identified in Perimyotis subflavus near Little Orleans, MD, and bat norovirus. We observed that bat norovirus formed virus-like particles and had epitopes and receptor-binding patterns similar to those of human noroviruses. To determine whether these observations stretch across multiple bat caliciviruses, we characterized a novel bat calicivirus, BtCalV/A10/USA/2009. Phylogenetic analysis revealed that BtCalV/A10/USA/2009 likely represents a novel Caliciviridae genus and is most closely related to "recoviruses." Homology modeling revealed that the capsid sequences of BtCalV/A10/USA/2009 and bat norovirus resembled human norovirus capsid sequences and retained host ligand binding within the receptor-binding domains similar to that seen with human noroviruses. Both caliciviruses bound histo-blood group antigens in patterns that overlapped those seen with human and animal noroviruses. Taken together, our results indicate the potential for bat caliciviruses to bind histo-blood group antigens and overcome a significant barrier to cross-species transmission. Additionally, we have shown that bat norovirus maintains antigenic epitopes similar to those seen with human noroviruses, providing further evidence of evolutionary descent. Our results reiterate the importance of surveillance of wild-animal populations, especially of bats, for novel viral pathogens. IMPORTANCE Caliciviruses are

Mejoramiento de la germinación, control de la hiperhidricidad y formación de brotes en Vasconcellea stipulata Badillo

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Diego Paúl Vélez-Mora

2015-07-01

Full Text Available Vasconcellea stipulata posee una gran importancia comercial debido a su actividad enzimática y como fuente para el mejoramiento genético de papaya, debido a su resistencia al virus de la mancha anular de esta especie. Sin embargo, debido a su baja regeneración por semillas y al limitado conocimiento de sus propiedades genéticas y farmacéuticas, esta especie no es cultivada ampliamente. La propagación a través del cultivo in vitro de semillas se ha usado para contrarrestar este tipo de problema, pero la hiperhidricidad, un trastorno fisiológico, expresado principalmente en los ejes embrionarios en desarrollo y asociado específicamente a esta especie, es una restricción significativa. Con el fin de obtener material de élite para el cultivo de V. stipulata, el objetivo de este trabajo fue incrementar la germinación, controlar la hiperhidricidad en embriones y evaluar el potencial para inducir respuestas morfogénicas, es decir, la formación de brotes. Nuestros resultados mostraron que es posible aumentar la germinación hasta un 53% en condiciones in vitro, dentro de un período más corto en presencia de peróxido de hidrógeno. Además, la hiperhidricidad se redujo significativamente (50% en condiciones in vitro cuando se incluyó ácido giberélico en bajas concentraciones en el medio 1/2 Nitsch y Nitsch. Esto permitió recuperar hasta aproximadamente el 80% de plántulas viables. Finalmente, otros reguladores de crecimiento vegetal evaluados, indujeron la formación de brotes en yemas axilares y la formación de callos en secciones de hoja derivadas de plántulas.

Next-Generation Sequencing Analysis of the Diversity of Human Noroviruses in Japanese Oysters.

Science.gov (United States)

Imamura, Saiki; Kanezashi, Hiromi; Goshima, Tomoko; Haruna, Mika; Okada, Tsukasa; Inagaki, Nobuya; Uema, Masashi; Noda, Mamoru; Akimoto, Keiko

2017-08-01

To obtain detailed information on the diversity of infectious norovirus in oysters (Crossostrea gigas), oysters obtained from fish producers at six different sites (sites A, B, C, D, E, and F) in Japan were analyzed once a month during the period spanning October 2015-February 2016. To avoid false-positive polymerase chain reaction (PCR) results derived from noninfectious virus particles, samples were pretreated with RNase before reverse transcription-PCR (RT-PCR). RT-PCR products were subjected to next-generation sequencing to identify norovirus genotypes in oysters. As a result, all GI genotypes were detected in the investigational period. The detection rate and proportion of norovirus GI genotypes differed depending on the sampling site and month. GII.3, GII.4, GII.13, GII.16, and GII.17 were detected in this study. Both the detection rate and proportion of norovirus GII genotypes differed depending on the sampling site and month. In total, the detection rate and proportion of GII.3 were highest from October to December among all detected genotypes. In January, the detection rates of GII.4 and GII.17 reached the same level as that of GII.3. The proportion of GII.17 was relatively lower from October to December, whereas it was the highest in January. To our knowledge, this is the first investigation on noroviruses in oysters in Japan, based on a method that can distinguish their infectivity.

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

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.

[Inactivating Effect of Heat-Denatured Lysozyme on Murine Norovirus in Bread Fillings].

Science.gov (United States)

Takahashi, Michiko; Yasuda, Yuka; Takahashi, Hajime; Takeuchi, Akira; Kuda, Takashi; Kimura, Bon

2018-01-01

In this study, we investigated the viability of murine norovirus strain 1 (MNV-1), a surrogate for human norovirus, in bread fillings used for making stuffed buns and pastries. The inactivating effect of heat-denatured lysozyme, which was recently reported to have an antiviral effect, on MNV-1 contaminating the bread fillings was also examined. MNV-1 was inoculated into two types of fillings (chocolate cream, marmalade jam) at 4.5 log PFU/g, and the bread fillings were stored at 4℃ for 5 days. MNV-1 remained viable in the bread fillings during storage. However, addition of 1% heat-denatured lysozyme to the fillings resulted in a decrease of MNV-1 infectivity immediately after inoculation, in both fillings. On the fifth day of storage, MNV-1 infectivity was decreased by 1.2 log PFU/g in chocolate cream and by 0.9 log PFU/g in marmalade jam. Although the mechanism underlying the anti-norovirus effect of heat-denatured lysozyme has not been clarified, our results suggest that heat-denatured lysozyme can be used as an inactivating agent against norovirus in bread fillings.

Systematic analysis of funding awarded for norovirus research to institutions in the United Kingdom, 1997-2010.

Science.gov (United States)

Head, Michael G; Fitchett, Joseph R; Atun, Rifat

2014-03-01

Norovirus infections pose great economic and disease burden to health systems around the world. This study quantifies the investments in norovirus research awarded to UK institutions over a 14-year time period. A systematic analysis of public and philanthropic infectious disease research investments awarded to UK institutions between 1997 and 2010. None UK institutions carrying out infectious disease research. Total funding for infectious disease research, total funding for norovirus research, position of norovirus research along the R&D value chain. The total dataset consisted of 6165 studies with sum funding of £2.6 billion. Twelve norovirus studies were identified with a total funding of £5.1 million, 0.2% of the total dataset. Of these, eight were categorized as pre-clinical, three as intervention studies and one as implementation research. Median funding was £200,620. Research funding for norovirus infections in the UK appears to be unacceptably low, given the burden of disease and disability produced by these infections. There is a clear need for new research initiatives along the R&D value chain: from pre-clinical through to implementation research, including trials to assess cost-effectiveness of infection control policies as well as clinical, public health and environmental interventions in hospitals, congregate settings and in the community.

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

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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.

Enterovirus and Norovirus Monitoring under UCMR3

Science.gov (United States)

This presentation describes the Unregulated Contaminant Monitoring Rule round 3 (UCMR3) monitoring program for enterovirus and norovirus in groundwater. It provides the data on microbial indicators and virus occurrence during the monitoring period. Enteric virus occurrence was ab...

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

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Pedraza-Avilés Alberto González

2002-01-01

Full Text Available 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 porcentajes de sensibilidad. La concentración inhibitoria mínima (CIM se obtuvo por microdilución semiautomatizada. Se utilizó un secuenciador automatizado de DNA para el análisis de variación de secuencias en los genes que codifican para proteína M y SpeA. Resultados. Todas las cepas fueron sensibles a beta-lactámicos y clindamicina; 12.7% fueron resistentes a eritromicina. El serotipo M2 fue el más frecuente, 27 del total. Prácticamente todas las bacterias (96% con el gen SpeA tienen el gen que codifica para el serotipo M2. Conclusiones. Debido a la reciente reaparición de infecciones por SGA se sugiere realizar estudios tanto de sensibilidad a macrólidos y beta-lactámicos, como de epidemiología molecular.

Genomic diversity and phylogeography of norovirus in China.

Science.gov (United States)

Qiao, Niu; Ren, He; Liu, Lei

2017-10-03

Little is known about the phylogeography of norovirus (NoV) in China. In norovirus, a clear understanding for the characteristics of tree topology, migration patterns and its demographic dynamics in viral circulation are needed to identify its prevalence trends, which can help us better prepare for its epidemics as well as develop useful control strategies. The aim of this study was to explore the genetic diversity, temporal distribution, demographic dynamics and migration patterns of NoV that circulated in China. Our analysis showed that two major genogroups, GI and GII, were identified in China, in which GII.3, GII.4 and GII.17 accounted for the majority with a total proportion around 70%. Our demography inference suggested that during the long-term migration process, NoV evolved into multiple lineages and then experienced a selective sweep, which reduced its genetic diversity. The phylogeography results suggested that the norovirus may have originated form the South China (Hong Kong and Guangdong), followed by multicenter direction outbreaks across the country. From these analyses, we indicate that domestic poultry trade and frequent communications of people from different regions have all contributed to the spread of the NoV in China. Together with recent advances in phylogeographic inference, our researches also provide powerful illustrations of how coalescent-based methods can extract adequate information in molecular epidemiology.

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.

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

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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

Estimating the Hospital Burden of Norovirus-Associated Gastroenteritis in England and its Opportunity Costs for Non-Admitted Patients.

Science.gov (United States)

Sandmann, Frank G; Shallcross, Laura; Adams, Natalie; Allen, David J; Coen, Pietro G; Jeanes, Annette; Kozlakidis, Zisis; Larkin, Lesley; Wurie, Fatima; Robotham, Julie V; Jit, Mark; Deeny, Sarah R

2018-02-26

Norovirus places a substantial burden on healthcare systems, arising from infected patients, disease outbreaks, beds kept unoccupied for infection control, and staff absences due to infection. In settings with high rates of bed occupancy, opportunity costs arise from patients who cannot be admitted due to beds being unavailable. With several treatments and vaccines against norovirus in development, quantifying the expected economic burden is timely. The number of inpatients with norovirus-associated gastroenteritis in England were modelled using infectious and non-infectious gastrointestinal Hospital Episode Statistics codes and laboratory reports of gastrointestinal pathogens collected at Public Health England. The excess length of stay from norovirus was estimated with a multi-state model and local outbreak data. Unoccupied bed-days and staff absences were estimated from national outbreak surveillance. The burden was valued conventionally using accounting expenditures and wages, which we contrasted to the opportunity costs from forgone patients using a novel methodology. Between July 2013 and June 2016, 17.7% (95%-confidence interval: 15.6%‒21.6%) of primary and 23.8% (20.6%‒29.9%) of secondary gastrointestinal diagnoses were norovirus-attributable. Annually, the estimated median 290,000 (interquartile range: 282,000‒297,000) occupied and unoccupied bed-days used for norovirus displaced 57,800 patients. Conventional costs for the National Health Service reached £107.6 million; the economic burden approximated to £297.7 million and a loss of 6,300 quality-adjusted life years annually. In England, norovirus is now the second-largest contributor of the gastrointestinal hospital burden. With the projected impact being greater than previously estimated, improved capture of relevant opportunity costs seems imperative for diseases like norovirus.

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

Sources and persistence of human noroviruses in fresh produce chains and associated public health risks

NARCIS (Netherlands)

Verhaelen, K.

2014-01-01

Human norovirus is a frequent cause of gastroenteritis worldwide, and viewed as the most common cause of foodborne disease. Numerous norovirus outbreaks associated with fresh produce, especially soft-berries and lettuce are described. Risk management strategies need to be improved in order to reduce

An outbreak of norovirus infection in a long-term care facility in Brazil

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Fernando Gatti de Menezes

2010-12-01

Full Text Available Objective: To describe a norovirus outbreak in a Brazilian longtermcare facility from July 8 to 29, 2005. Methods: In thefirst 48 to 72 hours after onset of symptoms in inpatients andemployees, the main infection control strategies were staffeducation, emphasis on hand washing, implementing contactprecautions up to 48-72 hours after resolution of symptoms,complete cleaning of the rooms and exclusion of symptomaticemployees from work until 48-72 hours after resolution of theirsymptoms. Epidemiological and clinical characteristics of thenorovirus infections were described based on chart review.Results: The incidence among inpatients and employees was41.3% and 16.25%, respectively. The main symptom was diarrhea,affecting 100% of inpatients and employees. Forty-four percent ofspecimens were positive by RIDASCREEN® Norovirus analyses,and identified as norovirus genogroup GII. Seventy percent ofinpatients were women and their age range was 51-98 years.Inpatients had in average two comorbid conditions – 87.3% withcardiovascular or chronic pulmonary condition and 47.6% withdementia. There was not relapse or death. Conclusions: The earlyinfection-control measures associated to surveillance are requiredto keep long-term care facilities free of noroviruses and to protectthose who are most vulnerable.

Intranasal delivery of a bivalent norovirus vaccine formulated in an in situ gelling dry powder.

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Jordan P Ball

Full Text Available The global health community is beginning to understand the burden of norovirus-associated disease, which has a significant impact in both developed and developing countries. Norovirus virus like particle (VLP-based vaccines are currently under development and have been shown to elicit systemic and mucosal immune responses when delivered intranasally. In the present study, we describe the use of a dry powder formulation (GelVac™ with an in situ gelling polysaccharide (GelSite™ extracted from Aloe vera for nasal delivery of a bivalent vaccine formulation containing both GI and GII.4 norovirus VLPs. Dose-ranging studies were performed to identify the optimal antigen dosages based on systemic and mucosal immune responses in guinea pigs and determine any antigenic interference. A dose-dependent increase in systemic and mucosal immunogenicity against each of the VLPs were observed as well as a boosting effect for each VLP after the second dosing. A total antigen dose of ≥50 μg of each GI and GII.4 VLPs was determined to be the maximally immunogenic dose in guinea pigs. The immunogenicity results of this bivalent formulation, taken together with previous work on monovalent GelVac™ norovirus vaccine formulation, provides a basis for future development of this norovirus VLP vaccine.

High pressure inactivation of human norovirus-like particles: evidence that the capsid of human norovirus is highly pressure resistant

Science.gov (United States)

High pressure processing (HPP) is a promising non-thermal technology to inactivate foodborne viruses. However, the effectiveness of HPP on inactivating human norovirus (HuNoV), the leading cause of acute gastroenteritis, is unknown because it cannot be propagated in cell culture. Therefore, developi...

A State-by-State Assessment of Food Service Regulations for Prevention of Norovirus Outbreaks.

Science.gov (United States)

Kambhampati, Anita; Shioda, Kayoko; Gould, L Hannah; Sharp, Donald; Brown, Laura G; Parashar, Umesh D; Hall, Aron J

2016-09-01

Noroviruses are the leading cause of foodborne disease in the United States. Foodborne transmission of norovirus is often associated with contamination of food during preparation by an infected food worker. The U.S. Food and Drug Administration's Food Code provides model food safety regulations for preventing transmission of foodborne disease in restaurants; however, adoption of specific provisions is at the discretion of state and local governments. We analyzed the food service regulations of all 50 states and the District of Columbia (i.e., 51 states) to describe differences in adoption of norovirus-related Food Code provisions into state food service regulations. We then assessed potential correlations between adoption of these regulations and characteristics of foodborne norovirus outbreaks reported to the National Outbreak Reporting System from 2009 through 2014. Of the 51 states assessed, all (100%) required food workers to wash their hands, and 39 (76%) prohibited bare-hand contact with ready-to-eat food. Thirty states (59%) required exclusion of staff with vomiting and diarrhea until 24 h after cessation of symptoms. Provisions requiring a certified food protection manager (CFPM) and a response plan for contamination events (i.e., vomiting) were least commonly adopted; 26 states (51%) required a CFPM, and 8 (16%) required a response plan. Although not statistically significant, states that adopted the provisions prohibiting bare-hand contact (0.45 versus 0.74, P =0.07), requiring a CFPM (0.38 versus 0.75, P =0.09), and excluding ill staff for ≥24 h after symptom resolution (0.44 versus 0.73, P =0.24) each reported fewer foodborne norovirus outbreaks per million person-years than did those states without these provisions. Adoption and compliance with federal recommended food service regulations may decrease the incidence of foodborne norovirus outbreaks.

Incidence of Norovirus-Associated Medical Encounters among Active Duty United States Military Personnel and Their Dependents.

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Brian Rha

Full Text Available Norovirus is a leading cause of gastroenteritis episodes and outbreaks in US military deployments, but estimates of endemic disease burden among military personnel in garrison are lacking.Diagnostic codes from gastroenteritis-associated medical encounters of active duty military personnel and their beneficiaries from July 1998-June 2011 were obtained from the Armed Forces Health Surveillance Center. Using time-series regression models, cause-unspecified encounters were modeled as a function of encounters for specific enteropathogens. Model residuals (representing unexplained encounters were used to estimate norovirus-attributable medical encounters. Incidence rates were calculated using population data for both active duty and beneficiary populations.The estimated annual mean rate of norovirus-associated medically-attended visits among active duty personnel and their beneficiaries was 292 (95% CI: 258 to 326 and 93 (95% CI: 80 to 105 encounters per 10,000 persons, respectively. Rates were highest among beneficiaries <5 years of age with a median annual rate of 435 (range: 318 to 646 encounters per 10,000 children. Norovirus was estimated to cause 31% and 27% of all-cause gastroenteritis encounters in the active duty and beneficiary populations, respectively, with over 60% occurring between November and April. There was no evidence of any lag effect where norovirus disease occurred in one population before the other, or in one beneficiary age group before the others.Norovirus is a major cause of medically-attended gastroenteritis among non-deployed US military active duty members as well as in their beneficiaries.

Emergence of Noroviruses homologous to strains reported from Djibouti (horn of Africa), Brazil, Italy, Japan and USA among children in Kolkata, India.

Science.gov (United States)

Nataraju, S M; Ganesh, B; Das, S; Chowdhury, S; Nayak, M K; Ghosh, M; Chatterjee, M K; Sarkar, U; Mitra, U; Bhattacharya, M K; Arora, R; Kobayashi, N; Krishnan, T

2010-09-01

A total of 625 faecal specimens of diarrheic cases (n-313) and non diarrheic controls (n-312), were screened by RT-PCR to detect Noroviruses in children aged below 5 years in Kolkata, India. Out of the 313 fecal specimens (cases) screened using CDC primer set, 10 (3.19%) showed amplification in reverse transcription-polymerase chain reaction (RT-PCR) for Norovirus. These included 5 of 260 (1.92%) from hospitalized and 5 of 53 (9.43%) from out patients departament (OPD) cases. Nine (90%) of Norovirus positive cases belonged to genogroup GII and one specimen (10%) was positive for genogroup GI. Among the 312 non diarrheic controls 2 (0.63%) were positive for Norovirus GII. Partial RNA dependent RNA polymerase gene (RdRp) sequences corresponding to the six Norovirus GII positive samples showed homology to the sequences of Djibouti (horn of Africa), Brazil, Italy, Japan and US norovirus strains. This study shows the detection of newly emerging Norovirus strains among diarrheic and non diarrheic children in Kolkata.

Molecular surveillance of norovirus, 2005-16: an epidemiological analysis of data collected from the NoroNet network.

NARCIS (Netherlands)

van Beek, Janko; de Graaf, Miranda; Al-Hello, Haider; Allen, David J; Ambert-Balay, Katia; Botteldoorn, Nadine; Brytting, Mia; Buesa, Javier; Cabrerizo, Maria; Chan, Martin; Cloak, Fiona; Di Bartolo, Ilaria; Guix, Susana; Hewitt, Joanne; Iritani, Nobuhiro; Jin, Miao; Johne, Reimar; Lederer, Ingeborg; Mans, Janet; Martella, Vito; Maunula, Leena; McAllister, Georgina; Niendorf, Sandra; Niesters, Hubert G; Podkolzin, Alexander T; Poljsak-Prijatelj, Mateja; Rasmussen, Lasse Dam; Reuter, Gábor; Tuite, Gráinne; Kroneman, Annelies; Vennema, Harry; Koopmans, Marion P G

2018-01-01

The development of a vaccine for norovirus requires a detailed understanding of global genetic diversity of noroviruses. We analysed their epidemiology and diversity using surveillance data from the NoroNet network.

Factores de riesgo asociados a infección aguda por hepatitis B en población militar destacada al departamento de Amazonas, Perú

OpenAIRE

César Cabezas; J. Jaime Miranda; Giovana Romero; Magna Suáre; Frine Samalvides; Juan Echevarría; Juan D. Valdivia; Walter A. Valdivia

2007-01-01

El Perú es considerado un país de endemicidad intermedia-alta para el virus de hepatitis B (VHB), con variaciones entre diferentes regiones. Existen pocos reportes del problema de infección por el VHB en personal militar. Objetivos. Determinar los factores de riesgo asociados con el desarrollo de infección por el VHB en un brote epidémico en personal militar destacado en Ampama, Amazonas, Perú. Material y métodos. Estudio caso-control en personal militar destacado al puesto de Ampama y a la b...

Ice-associated norovirus outbreak predominantly caused by GII.17 in Taiwan, 2015.

Science.gov (United States)

Cheng, Hao-Yuan; Hung, Min-Nan; Chen, Wan-Chin; Lo, Yi-Chun; Su, Ying-Shih; Wei, Hsin-Yi; Chen, Meng-Yu; Tuan, Yen-Chang; Lin, Hui-Chen; Lin, Hsu-Yang; Liu, Tsung-Yen; Wang, Yu-Ying; Wu, Fang-Tzy

2017-11-07

On 5 March 2015, Taiwan Centers for Disease Control was notified of more than 200 students with gastroenteritis at a senior high school during excursion to Kenting. We conducted an outbreak investigation to identify the causative agent and possible vehicle of the pathogen. We conducted a retrospective cohort study by using a structured questionnaire to interview all students for consumed food items during their stay at the resort. Students were defined as a gastroenteritis case while having vomiting or diarrhea after the breakfast on 4 March. We inspected the environment to identify possible contamination route. We collected stool or vomitus samples from ill students, food handlers and environmental specimens for bacterial culture for common enteropathogens, reverse transcription polymerase chain reaction (RT-PCR) for norovirus and enzyme-linked immunosorbent assay (ELISA) for rotavirus. Norovirus PCR-positive products were then sequenced and genotyped. Of 267 students enrolled, 144 (54%) met our case definition. Regression analysis revealed elevated risk associated with iced tea, which was made from tea powder mixed with hot water and self-made ice (risk ratio 1.54, 95% confidence interval 1.22-1.98). Ice used for beverages, water before and after water filter of the ice machine and 16 stool and vomitus samples from ill students were tested positive for norovirus; Multiple genotypes were identified including GI.2, GI.4 and GII.17. GII.17 was the predominant genotype and phylogenetic analyses showed that noroviruses identified in ice, water and human samples were clustered into the same genotypes. Environmental investigation revealed the ice was made by inadequate-filtered and un-boiled water. We identified the ice made by norovirus-contaminated un-boiled water caused the outbreak and the predominant genotype was GII.17. Adequately filtered or boiled water should be strongly recommended for making ice to avoid possible contamination.

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

International Nuclear Information System (INIS)

Chang, Kyeong-Ok; Takahashi, Daisuke; Prakash, Om; Kim, Yunjeong

2012-01-01

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.

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.

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.

Brote de legionelosis en Murcia en julio de 2001. La óptica de sanidad ambiental

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C. Gutiérrez Molina

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

[Survey on a public health emergency event caused by norovirus].

Science.gov (United States)

Xing, Y; Jiang, C; Hua, W Y; Liu, F; Zhao, Z; Ding, Y J; Wang, L; Li, J

2017-09-10

Objective: To study the epidemiological characteristics of an outbreak caused by norovirus infection in a school in Haidian district, Beijing. Methods: Basic information of the school and data related to patients in the fields survey were collected and analyzed descriptively. Laboratory tests were performed to test the stool and anal swab specimens of both patients and cooks as well as the environmental specimens. Risk factors related to the incidence were analyzed through a case-control study. Results: A total number of 119 patients were identified in the school. Clinical symptoms were mild, mainly involving vomiting (94.1 % , 112/119), abdominal pain (46.2 % , 55/119), but no need of hospitalization. The average age of the student patients was 6.38, with minimum and maximum between 5 and 11. Patients were found in 22 classes, but mainly in grade 1 and class 7 where 35 patients were found (30.17 % ). A total of 134 specimens of rectal swabs and stool were collected, with 7 positive for norovirus and 6 for sappovirus. Salmonella, Shigella, lapactic Escherichia coli and Vibrio parahaemolyticus were not found in on dinner sets, residual foods, bottled water or in drinking fountains. Index on water hygiene was unsatisfactory in classrooms or dormitories where more cases were found. Accommodation, north-facing-classrooms, abnormal water hygiene indexes were found related to the occurance of the disease ( P <0.05). Conclusions: The outbreak was identified a gastroenteritis infection, caused by norovirus with symptoms as vomiting and abdominal pain. This event reached the reporting standards of public health emergencies-level Ⅳ. Discovery and isolation of the first case was not timely while transmission of the disease might be water-borne. Surveillance programs on symptoms, disinfection of vomit and stool in places like nurseries and schools should be strengthened to prevent the norovirus outbreak.

Membrane alterations induced by nonstructural proteins of human norovirus.

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Sylvie Y Doerflinger

2017-10-01

Full Text Available Human noroviruses (huNoV are the most frequent cause of non-bacterial acute gastroenteritis worldwide, particularly genogroup II genotype 4 (GII.4 variants. The viral nonstructural (NS proteins encoded by the ORF1 polyprotein induce vesical clusters harboring the viral replication sites. Little is known so far about the ultrastructure of these replication organelles or the contribution of individual NS proteins to their biogenesis. We compared the ultrastructural changes induced by expression of norovirus ORF1 polyproteins with those induced upon infection with murine norovirus (MNV. Characteristic membrane alterations induced by ORF1 expression resembled those found in MNV infected cells, consisting of vesicle accumulations likely built from the endoplasmic reticulum (ER which included single membrane vesicles (SMVs, double membrane vesicles (DMVs and multi membrane vesicles (MMVs. In-depth analysis using electron tomography suggested that MMVs originate through the enwrapping of SMVs with tubular structures similar to mechanisms reported for picornaviruses. Expression of GII.4 NS1-2, NS3 and NS4 fused to GFP revealed distinct membrane alterations when analyzed by correlative light and electron microscopy. Expression of NS1-2 induced proliferation of smooth ER membranes forming long tubular structures that were affected by mutations in the active center of the putative NS1-2 hydrolase domain. NS3 was associated with ER membranes around lipid droplets (LDs and induced the formation of convoluted membranes, which were even more pronounced in case of NS4. Interestingly, NS4 was the only GII.4 protein capable of inducing SMV and DMV formation when expressed individually. Our work provides the first ultrastructural analysis of norovirus GII.4 induced vesicle clusters and suggests that their morphology and biogenesis is most similar to picornaviruses. We further identified NS4 as a key factor in the formation of membrane alterations of huNoV and

High pressure inactivation of human norovirus virus-like particles: evidence that the capsid of human norovirus is highly pressure resistant

Science.gov (United States)

Human norovirus (NoV) is the leading cause of non-bacterial acute gastroenteritis epidemics worldwide. High pressure processing (HPP) has been considered a promising non-thermal processing technology to inactivate food- and water-borne viral pathogens. Due to the lack of an effective cell culture fo...

Evaluation of RIDA®GENE norovirus GI/GII real time RT-PCR using stool specimens collected from children and adults with acute gastroenteritis.

Science.gov (United States)

Kanwar, N; Hassan, F; Barclay, L; Langley, C; Vinjé, J; Bryant, P W; George, K St; Mosher, L; Matthews-Greer, J M; Rocha, M A; Beenhouwer, D O; Harrison, C J; Moffatt, M; Shastri, N; Selvarangan, R

2018-04-10

Norovirus is the leading cause of epidemic and sporadic acute gastroenteritis (AGE) in the United States. Widespread prevalence necessitates implementation of accurate norovirus detection assays in clinical diagnostic laboratories. To evaluate RIDA ® GENE norovirus GI/GII real-time RT-PCR assay (RGN RT-PCR) using stool samples from patients with sporadic AGE. Patients between 14 days to 101 years of age with symptoms of AGE were enrolled prospectively at four sites across the United States during 2014-2015. Stool specimens were screened for the presence of norovirus RNA by the RGN RT-PCR assay. Results were compared with a reference method that included conventional RT-PCR and sequencing of a partial region of the 5'end of the norovirus ORF2 gene. A total of 259 (36.0%) of 719 specimens tested positive for norovirus by the reference method. The RGN RT-PCR assay detected norovirus in 244 (94%) of these 259 norovirus positive specimens. The sensitivity and specificity (95% confidence interval) of the RGN RT-PCR assay for detecting norovirus genogroup (G) I was 82.8% (63.5-93.5) and 99.1% (98.0-99.6) and for GII was 94.8% (90.8-97.2) and 98.6% (96.9-99.4), respectively. Seven specimens tested positive by the RGN-RT PCR that were negative by the reference method. The fifteen false negative samples were typed as GII.4 Sydney, GII.13, GI.3, GI.5, GI.2, GII.1, and GII.3 in the reference method. The RGN RT-PCR assay had a high sensitivity and specificity for the detection of norovirus in stool specimens from patients with sporadic AGE. Copyright © 2018. Published by Elsevier B.V.

A norovirus GII.P21 outbreak in a boarding school, Austria 2014.

Science.gov (United States)

Lin, Yung-Ching; Hipfl, Elisabeth; Lederer, Ingeborg; Allerberger, Franz; Schmid, Daniela

2015-08-01

An Austrian boarding school reported a cluster of gastroenteritis on January 10, 2014. Environmental swabs from the school cafeteria and a nearby kebab restaurant tested positive for norovirus. The outbreak was investigated to identify its source(s). An outbreak case was defined as a student or staff member with diarrhoea or vomiting that developed between January 7 and 13. Details on food exposure were collected via a self-administered questionnaire; risk ratios (RR) and 95% confidence intervals (CI) were calculated. Norovirus from the stool specimens of cases and asymptomatic kebab restaurant workers were genotyped. Twenty-eight cases were identified among 144 persons (attack rate 19%). The outbreak emerged and peaked on January 9, and ended on January 12. Compared to those who did not eat kebab, those who ate kebab on 7, 8, and 9 January were respectively 11 (95% CI 4.2-28), 6.7 (95% CI 3.4-13), and 9.3 (95% CI 4.0-22) times more likely to develop disease within the following 2 days. Stool specimens from three cases and three restaurant workers were positive for norovirus GII.P21. The kebab prepared by norovirus-positive restaurant workers was the most likely source of the outbreak. It is recommended that food handlers comply strictly with hand hygiene and avoid bare-handed contact with ready-to-eat food to minimize the risk of food-borne infection. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

[Recurrent epidemics of gastroenteritis caused by norovirus GI.3 in a small hotel].

Science.gov (United States)

Soini, Jani; Hemminki, Kaisa; Pirnes, Aija; Roivainen, Merja; Al-Hello, Haider; Maunula, Leena; Kauppinen, Ari; Miettinen, Likka; Smit, Pieter W; Huusko, Sari; Toikkanen, Salla; Rimhanen-Finne, Ruska

2016-01-01

Recurrent cases of gastroenteritis occurred in a small hotel. The causative agent of disease could not be detected. The cause and the source of the disease were established through epidemiological investigations and laboratory diagnosis. The causative agent of the disease was norovirus GI.3. Norovirus GI was detected in the water from the well and on surfaces at the hotel. Both epidemiological investigations and laboratory diagnostics are needed in resolving epidemics. Continuous development of laboratory methods is important.

Development of artificial intelligence approach to forecasting oyster norovirus outbreaks along Gulf of Mexico coast.

Science.gov (United States)

Chenar, Shima Shamkhali; Deng, Zhiqiang

2018-02-01

This paper presents an artificial intelligence-based model, called ANN-2Day model, for forecasting, managing and ultimately eliminating the growing risk of oyster norovirus outbreaks. The ANN-2Day model was developed using Artificial Neural Network (ANN) Toolbox in MATLAB Program and 15-years of epidemiological and environmental data for six independent environmental predictors including water temperature, solar radiation, gage height, salinity, wind, and rainfall. It was found that oyster norovirus outbreaks can be forecasted with two-day lead time using the ANN-2Day model and daily data of the six environmental predictors. Forecasting results of the ANN-2Day model indicated that the model was capable of reproducing 19years of historical oyster norovirus outbreaks along the Northern Gulf of Mexico coast with the positive predictive value of 76.82%, the negative predictive value of 100.00%, the sensitivity of 100.00%, the specificity of 99.84%, and the overall accuracy of 99.83%, respectively, demonstrating the efficacy of the ANN-2Day model in predicting the risk of norovirus outbreaks to human health. The 2-day lead time enables public health agencies and oyster harvesters to plan for management interventions and thus makes it possible to achieve a paradigm shift of their daily management and operation from primarily reacting to epidemic incidents of norovirus infection after they have occurred to eliminating (or at least reducing) the risk of costly incidents. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Intoxicación alimentaria por consumo de carne de caimán negro (Melanosuchus niger en el internado indígena de Nazareth, Amazonas, abril de 1997

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Martha C. Suárez

2000-03-01

Full Text Available Las intoxicaciones alimentarias son ocasionadas por consumo de alimentos en malas condiciones de preparación o de conservación o que han sufrido contaminación con agentes quimicos, fisicos o biológicos. La reciente incorporación de la vigilancia de este evento en el sistema de vigilancia intensificado de la Secretaria de Salud del Amazonas, ha permitido identificar la presencia de brotes de intoxicación alimentaria en el departamento. En abril de 1997, se informó a la Oficina de Epidemiologia de la Secretaria de Salud del Amazonas, la llegada de 30 pacientes al Hospital Empresa Social del Estado San Rafael de Leticia, con un cuadro clinico de dolor abdominal, vómito y cefalea. Las pacientes eran estudiantes adolescentes del internado indígena femenino de Nazareth, que presentaban como antecedente común la ingestión de pescado recalentado el día anterior a su consulta. En la investigación del presente brote de intoxicación alimentaria se comprobó por laboratorio que el alimento implicado era la carne de caimán negro, Melanosuchusniger, contaminada con Bacillus cereus. Esta carne iba a ser vendida como 'pescado seco' en Bogotá, por la gran demanda que tiene este alimento en la época de Semana Santa.

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.

Noroviruses Co-opt the Function of Host Proteins VAPA and VAPB for Replication via a Phenylalanine-Phenylalanine-Acidic-Tract-Motif Mimic in Nonstructural Viral Protein NS1/2.

Science.gov (United States)

McCune, Broc T; Tang, Wei; Lu, Jia; Eaglesham, James B; Thorne, Lucy; Mayer, Anne E; Condiff, Emily; Nice, Timothy J; Goodfellow, Ian; Krezel, Andrzej M; Virgin, Herbert W

2017-07-11

The Norovirus genus contains important human pathogens, but the role of host pathways in norovirus replication is largely unknown. Murine noroviruses provide the opportunity to study norovirus replication in cell culture and in small animals. The human norovirus nonstructural protein NS1/2 interacts with the host protein VAMP-associated protein A (VAPA), but the significance of the NS1/2-VAPA interaction is unexplored. Here we report decreased murine norovirus replication in VAPA- and VAPB-deficient cells. We characterized the role of VAPA in detail. VAPA was required for the efficiency of a step(s) in the viral replication cycle after entry of viral RNA into the cytoplasm but before the synthesis of viral minus-sense RNA. The interaction of VAPA with viral NS1/2 proteins is conserved between murine and human noroviruses. Murine norovirus NS1/2 directly bound the major sperm protein (MSP) domain of VAPA through its NS1 domain. Mutations within NS1 that disrupted interaction with VAPA inhibited viral replication. Structural analysis revealed that the viral NS1 domain contains a mimic of the phenylalanine-phenylalanine-acidic-tract (FFAT) motif that enables host proteins to bind to the VAPA MSP domain. The NS1/2-FFAT mimic region interacted with the VAPA-MSP domain in a manner similar to that seen with bona fide host FFAT motifs. Amino acids in the FFAT mimic region of the NS1 domain that are important for viral replication are highly conserved across murine norovirus strains. Thus, VAPA interaction with a norovirus protein that functionally mimics host FFAT motifs is important for murine norovirus replication. IMPORTANCE Human noroviruses are a leading cause of gastroenteritis worldwide, but host factors involved in norovirus replication are incompletely understood. Murine noroviruses have been studied to define mechanisms of norovirus replication. Here we defined the importance of the interaction between the hitherto poorly studied NS1/2 norovirus protein and the

Higiene alimentaria para la prevención de trastornos digestivos infecciosos y por toxinas

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G. Manuel Moreno, Dr.

2010-09-01

Full Text Available El principal factor que interviene en el origen y prevención de las enfermedades trasmitidas por los alimentos es la higiene alimentaria. Dichas enfermedades son causadas por la ingestión de alimentos o agua contaminados con microorganismos patógenos ocasionando una infección o por la ingestión de alimentos contaminados con toxinas. Los principales agentes involucrados son Escherichia Coli, Campylobacter, Salmonella, Shigella, Listeria Monocytogenes, Norovirus, virus Hepatitis A, Astrovirus, Rotavirus, y Virus Coxsackie. Toxinas producidas por hongos o por microflora marina y los contaminantes orgánicos persistentes pueden también causar serios problemas de salud. La inocuidad alimentaría ha tomado relevancia debido a una mayor exigencia por consumidores cada día más informados y por las demandas del comercio exterior. Medidas que aseguren una adecuada higiene alimentaría nos permitirá prevenir enfermedades, principalmente digestivas, causadas por variados agentes en los alimentos. Esto se logra por la implementación de las medidas propuestas por la Comisión Internacional conocida como Codex Alimentarius.

Incidence of Norovirus-Associated Diarrhea and Vomiting Disease Among Children and Adults in a Community Cohort in the Peruvian Amazon Basin.

Science.gov (United States)

Romero, Candice; Tinoco, Yeny O; Loli, Sebastian; Razuri, Hugo; Soto, Giselle; Silva, María; Galvan, Patricia; Kambhampati, Anita; Parashar, Umesh D; Kasper, Matthew R; Bausch, Daniel G; Simons, Mark P; Lopman, Benjamin

2017-09-01

Data on norovirus epidemiology among all ages in community settings are scarce, especially from tropical settings. We implemented active surveillance in 297 households in Peru from October 2012 to August 2015 to assess the burden of diarrhea and acute gastroenteritis (AGE) due to norovirus in a lower-middle-income community. During period 1 (October 2012-May 2013), we used a "traditional" diarrhea case definition (≥3 loose/liquid stools within 24 hours). During period 2 (June 2013-August 2015), we used an expanded case definition of AGE (by adding ≥2 vomiting episodes without diarrhea or 1-2 vomiting episodes plus 1-2 loose/liquid stools within 24 hours). Stool samples were tested for norovirus by reverse-transcription polymerase chain reaction. During period 1, overall diarrhea and norovirus-associated diarrhea incidence was 37.2/100 person-years (PY) (95% confidence interval [CI], 33.2-41.7) and 5.7/100 PY (95% CI, 3.9-8.1), respectively. During period 2, overall AGE and norovirus-associated AGE incidence was 51.8/100 PY (95% CI, 48.8-54.9) and 6.5/100 PY (95% CI, 5.4-7.8), respectively. In both periods, children aged accounting for 35% (7/20) of all cases in this age group. Noroviruses were identified in 7% (23/335) of controls free of gastroenteric symptoms. Norovirus was a significant cause of AGE in this community, especially among children definition resulted in a 20% improvement for detection of norovirus cases. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

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; Hansman, Grant S

2016-01-01

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 setting, the

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

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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.

Epidemiological evaluation of sporadic cases of Norovirus infection in comunitary and hospitalized patients

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Sara Giordana Rimoldi

2009-03-01

Full Text Available Surveillace of viral gastoenteritis infections is very poor in Italy, even if starting from 2004 Norovirus became one of the most causative agent of infections in all the seasons. The aim of our study was to evaluate the isolation of Norovirus both in hospitalizes patients and communitary patients. From October 2006 to March 2008 we examined 400 samples. Our results showed only 15 sporadic cases in pediatric, HIV comunitary patients. These cases were analyzed by using an ELISA screening (Biopharm and the results were confirmed with real time PCT (Argene.

CULTIVO in vitro DE PITAYO (Stenocereus stellatus [Pfeiffer] Riccobono

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Ylvi María Martínez Villegas

2011-01-01

Full Text Available El pitayo (Stenocereus stellatus es una cactacea nativa de Mexico, apreciada por sus frutos, los cuales tienen caracteristicas organolepticas unicas. Su propagacion es por esquejes tomados de plantas adultas, generalmente silvestres, causando deforestacion de zonas naturales. El objetivo fue definir el tipo y la dosis de citocininas asi como la concentracion de sacarosa que permita obtener mayor numero de plantas de pitayo in vitro. Se usaron semillas de frutos maduros de las cuales se obtuvieron plantulas para iniciar el incremento de plantas. Para la multiplicacion de brotes se utilizaron plantulas de 2 a 3 cm de altura divididas en secciones de 1 cm, el medio fue MS con 3 % de sacarosa; se evaluaron tres citocininas (kinetina, 6-benciladenina, y 2-isopentiladenina en cinco concentraciones (2.2, 4.4, 8.8, 17.6 y 35.2 ¿ÊM. Para el crecimiento de brotes se uso medio MS con sacarosa (1, 2, 3, 4 y 5 %. En la aclimatacion se evaluo el efecto de la concentracion de sacarosa usada para el crecimiento de los brotes in vitro. Se observo que la concentracion de 17.6 ¿ÊM de 6-benciladenina ocasiono formacion de brotes en todos los explantes, los cuales tuvieron ocho brotes por explante. Los brotes desarrollaron la mayor altura cuando fueron cultivados en 3 y 4 % de sacarosa. En aclimatacion sobrevivieron mas del 92 % de las plantas trasplantadas a sustrato.

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. PMID:24955857

Anatomía y morfogénesis de las agallas producidas por Leptocybe invasa en plantas de Eucalyptus

OpenAIRE

Gonzalez, Ana M; Solís, Stella M

2015-01-01

Leptocybe invasa o “avispa de la agalla del eucalipto”, es un microhimenóptero gallícola que ovipone en hojas jóvenes de eucaliptos. La planta responde formando agallas, que causan enrollamiento, defoliación y colapso de brotes, afectando seriamente la producción. En este trabajo se analizan los cambios morfogenéticos y anatómicos provocados por el desarrollo de las agallas, comparándolos con plantas sanas. Con técnicas tradicionales de microscopía óptica y electrónica de barrido se estudiaro...

Likely transmission of norovirus on an airplane, October 2008.

Science.gov (United States)

Kirking, Hannah L; Cortes, Jennifer; Burrer, Sherry; Hall, Aron J; Cohen, Nicole J; Lipman, Harvey; Kim, Curi; Daly, Elizabeth R; Fishbein, Daniel B

2010-05-01

On 8 October 2008, members of a tour group experienced diarrhea and vomiting throughout an airplane flight from Boston, Massachusetts, to Los Angeles, California, resulting in an emergency diversion 3 h after takeoff. An investigation was conducted to determine the cause of the outbreak, assess whether transmission occurred on the airplane, and describe risk factors for transmission. Passengers and crew were contacted to obtain information about demographics, symptoms, locations on the airplane, and possible risk factors for transmission. Case patients were defined as passengers with vomiting or diarrhea (> or =3 loose stools in 24 h) and were asked to submit stool samples for norovirus testing by real-time reverse-transcription polymerase chain reaction. Thirty-six (88%) of 41 tour group members were interviewed, and 15 (41%) met the case definition (peak date of illness onset, 8 October 2008). Of 106 passengers who were not tour group members, 85 (80%) were interviewed, and 7 (8%) met the case definition after the flight (peak date of illness onset, 10 October 2008). Multivariate logistic regression analysis showed that sitting in an aisle seat (adjusted relative risk, 11.0; 95% confidence interval, 1.4-84.9) and sitting near any tour group member (adjusted relative risk, 7.5; 95% confidence interval, 1.7-33.6) were associated with the development of illness. Norovirus genotype II was detected by reverse-transcription polymerase chain reaction in stool samples from case patients in both groups. Despite the short duration, transmission of norovirus likely occurred during the flight.

Environmental Factors Associated with Norovirus Transmission in Long-Term Care Facilities in South Carolina.

Science.gov (United States)

Jayasekara, Lalani; Leone, Cortney M; Sharp, Julia; Getty, Morgan

2016-09-01

In the U.S., 60% of norovirus outbreaks are attributed to long-term care facilities (LTCFs). A descriptive study of 26 LTCFs in South Carolina was conducted to determine the presence of environmental factors associated with transmission of human noroviruses. Sanitary conditions in one common area, one staff/visitor bathroom, and the main kitchen were assessed using two audit forms. While surfaces in all kitchens were in good sanitary condition, 23 LTCFs used quaternary ammonium-based sanitizers and three LTCFs used chlorine bleach for kitchen sanitization. All common areas were also clean and in good condition; however, 20 LTCFs had upholstered chairs, and five LTCFs had carpeted floors. Seven facilities used quaternary ammonium-based disinfectants exclusively, whereas six LTCFs used chlorine bleach exclusively, and eight LTCFs used both to disinfect common areas. Seven staff/visitor bathrooms were accessible to residents, and hand washing signage was missing from 10. These results reveal the presence of environmental factors that might facilitate norovirus transmission within LTCFs.

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.

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...

Variable high pressure processing sensitivities for GII human noroviruses

Science.gov (United States)

Human norovirus (HuNoV) is the leading cause of foodborne diseases worldwide. High pressure processing (HPP) is one of the most promising non-thermal technologies for decontamination of viral pathogens in foods. However, the survival of HuNoVs by HPP is poorly understood because these viruses cann...

High hydrostatic pressure processing of murine norovirus 1-contaminated oysters inhibits oral infection in STAT-1 -/- deficient female mice

Science.gov (United States)

We have previously demonstrated that high pressure processing (HPP) is effective in preventing in vitro replication of murine norovirus strain 1 (MNV-1), a human norovirus surrogate, in a monocyte cell line following extraction from MNV-1-contaminated oysters. In the present study, the efficacy of ...

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

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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.

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.

Variaciones Intra-Específicas en el crecimiento primario de Nothofagus dombeyi (Nothofagaceae Intra-specific variations in the primary growth of Nothofagus dombeyi (Nothofagaceae

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Javier Puntieri

2005-07-01

Full Text Available Se evaluó el patrón de crecimiento bajo condiciones controladas de los ejes foliados de 16 plántulas de Nothofagus dombeyi. Los individuos fueron ubicados en una cámara de crecimiento y se evaluó el crecimiento del tronco en dos eventos de crecimiento sucesivos (julio 2002 - marzo 2004. Se identificaron tres patrones de crecimiento del primer brote medido: (1 crecimiento ininterrumpido por unos 8 meses, (2 crecimiento interrumpido por un período de reposo no menor de 7 semanas, con rebrote posterior y (3 crecimiento ininterrumpido por 6 a 7 meses. En los individuos con los patrones de crecimiento 1 y 2, la tasa máxima de producción de hojas del primer brote producido fue mayor que en los individuos con el tercer patrón de crecimiento. La tasa media de crecimiento fue mayor para los brotes del primer grupo que para los de los otros dos grupos. El segundo de los brotes medidos se alargó en un único pulso y alcanzó menor tamaño que el primero de los brotes. Se discute el posible rol de gradientes ontogenéticos o de variaciones genéticas entre individuos de coihue como explicación de los diferentes patrones de crecimiento registrados.

High pressure processing's potential to inactivate norovirus and other fooodborne viruses

Science.gov (United States)

High pressure processing (HPP) can inactivate human norovirus. However, all viruses are not equally susceptible to HPP. Pressure treatment parameters such as required pressure levels, initial pressurization temperatures, and pressurization times substantially affect inactivation. How food matrix ...

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.

Comparative Virucidal Efficacy of Seven Disinfectants Against Murine Norovirus and Feline Calicivirus, Surrogates of Human Norovirus.

Science.gov (United States)

Zonta, William; Mauroy, Axel; Farnir, Frederic; Thiry, Etienne

2016-03-01

Human noroviruses (HuNoV) are the leading cause of acute non-bacterial gastroenteritis in humans and can be transmitted either by person-to-person contact or by consumption of contaminated food. A knowledge of an efficient disinfection for both hands and food-contact surfaces is helpful for the food sector and provides precious information for public health. The aim of this study was to evaluate the effect of seven disinfectants belonging to different groups of biocides (alcohol, halogen, oxidizing agents, quaternary ammonium compounds, aldehyde and biguanide) on infectious viral titre and on genomic copy number. Due to the absence of a cell culture system for HuNoV, two HuNoV surrogates, such as murine norovirus and feline calicivirus, were used and the tests were performed in suspension, on gloves and on stainless steel discs. When, as criteria of efficacy, a log reduction >3 of the infectious viral titre on both surrogates and in the three tests is used, the most efficacious disinfectants in this study appear to be biocidal products B, C and D, representing the halogens, the oxidizing agents group and a mix of QAC, alcohol and aldehyde, respectively. In addition, these three disinfectants also elicited a significant effect on genomic copy number for both surrogate viruses and in all three tests. The results of this study demonstrate that a halogen compound, oxidizing agents and a mix of QAC, alcohol and aldehyde are advisable for HuNoV disinfection of either potentially contaminated surfaces or materials in contact with foodstuffs.

ISO TS/15216; an international standard method for the detection and quantification of norovirus in high risk foodstuffs

DEFF Research Database (Denmark)

Lowther, James; Schultz, Anna Charlotte

Norovirus is one of the principal agents of food-related gastroenteritis. Outbreaks have been associated with a number of different food vehicles, most notably bivalve molluscan shellfish and soft fruit. Contamination of prepared food through contact with infected food handlers also presents...... and the application of the method to the testing of food samples implicated in outbreaks of norovirus gastroenteritis....

Role of Food Handlers in Norovirus Outbreaks in London and South East England, 2013 to 2015.

Science.gov (United States)

Rumble, C; Addiman, S; Balasegaram, S; Chima, K; Ready, D; Heard, J; Alexander, E

2017-02-01

Outbreaks caused by norovirus infection are common and occur throughout the year. Outbreaks can be related to food outlets either through a contaminated food source or an infected food handler. Both asymptomatic and symptomatic food handlers are potentially implicated in outbreaks, but evidence of transmission is limited. To understand potential food handler transmission in outbreak scenarios, epidemiological and microbiological data on possible and confirmed norovirus outbreaks reported in London and South East England in a 2-year period were reviewed. One hundred eighty-six outbreaks were associated with a food outlet or registered caterer in this period. These occurred throughout the year with peaks in quarter 1 of study years. A case series of 17 outbreaks investigated by the local field epidemiological service were evaluated further, representing more than 606 cases. In five outbreaks, symptomatic food handlers were tested and found positive for norovirus. In four outbreaks, symptomatic food handlers were not tested. Asymptomatic food handlers were tested in three outbreaks but positive for norovirus in one only. Environmental sampling did not identify the causative agent conclusively in any of the outbreaks included in this analysis. Food sampling identified norovirus in one outbreak. Recommendations from this study include for outbreak investigations to encourage testing of symptomatic food handlers and for food and environmental samples to be taken as soon as possible. In addition, sampling of asymptomatic food handlers should be considered when possible. However, in light of the complexity in conclusively identifying a source of infection, general measures to improve hand hygiene are recommended, with specific education among food handlers about the potential for foodborne pathogen transmission during asymptomatic infection, as well as reinforcing the importance of self-exclusion from food handling activities when symptomatic.

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

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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

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

Descripción de un brote de intoxicación alimentaria estafilocócica ocurrido en Las Rosas, Provincia de Santa Fe, Argentina

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Aníbal A. Brizzio

2011-03-01

Full Text Available En febrero de 2008 se denunció en la localidad santafecina de Las Rosas un presunto brote de una enfermedad transmitida por alimentos. En los procedimientos oficiales no fue posible determinar la cantidad de personas afectadas luego de consumir canelones de verdura adquiridos en un local comercial. Se auditó el establecimiento elaborador y se tomaron muestras del citado producto, muestras ambientales e hisopados de los manipuladores de alimentos. Se entrevistó a los afectados y se recuperaron restos del alimento ingerido. Mediante análisis microbiológicos de rutina se determinó la presencia de S. aureus subespecie aureus coagulasa positivo en muestras del producto consumido, del producto crudo y de los manipuladores del alimento. Los microorganismos indicadores no mostraron niveles significativos y no se aisló otro patógeno de transmisión alimentaria. Se investigó la presencia de genes productores de enterotoxinas estafilocócicas, con resultado positivo para la enterotoxina B en las cepas aisladas de un manipulador y en el alimento vinculado con el brote. Al analizar los aislamientos por SmaI-PFGE se demostró un 100% de similitud entre ellos. La notificación oportuna, las acciones sanitarias coordinadas y la disponibilidad de las herramientas de laboratorio apropiadas permitieron identificar los factores de protección y de riesgo, y cortar la cadena de transmisión de la enfermedad.On February 2008, a suspected foodborne outbreak was reported in Las Rosas (Santa Fe Province, Argentina. The formal procedures indicated that an undetermined number of individuals had experienced food poisoning following consumption of vegetable cannelloni bought at a local shop. The manufacturer establishment was audited. Samples from the suspected food, as well as environmental samples and swabs from food handlers were obtained and involved subjects were interviewed. Remnants of ingested food were also obtained. Routine microbiological procedures of

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...

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...

A One Year Study on the Concentrations of Norovirus and Enteric Adenoviruses in Wastewater and A Surface Drinking Water Source in Norway.

Science.gov (United States)

Grøndahl-Rosado, Ricardo C; Yarovitsyna, Ekaterina; Trettenes, Elin; Myrmel, Mette; Robertson, Lucy J

2014-12-01

Enteric viruses transmitted via the faecal-oral route occur in high concentrations in wastewater and may contaminate drinking water sources and cause disease. In order to quantify enteric adenovirus and norovirus genotypes I and II (GI and GII) impacting a drinking source in Norway, samples of surface water (52), wastewater inlet (64) and outlet (59) were collected between January 2011 and April 2012. Samples were concentrated in two steps, using an electropositive disc filter and polyethylene glycol precipitation, followed by nucleic acid extraction and analysis by quantitative polymerase chain reaction. Virus was detected in 47/52 (90.4%) of surface water, 59/64 (92%) of wastewater inlet and 55/59 (93%) of wastewater outlet samples. Norovirus GI occurred in the highest concentrations in surface water (2.51e + 04) and adenovirus in wastewater (2.15e + 07). While adenovirus was the most frequently detected in all matrices, norovirus GI was more frequently detected in surface water and norovirus GII in wastewater. This study is the first in Norway to monitor both sewage and a drinking water source in parallel, and confirms the year-round presence of norovirus and adenovirus in a Norwegian drinking water source.

Estudio clínico y epidemiológico de un brote de beriberi húmedo en Cartagena de Indias, Colombia, 1992-1993

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M. Martínez

1996-01-01

Full Text Available La presente investigación ha tenido como objetivo primordial aclarar la etiología de un cuadro clínico caracterizado por edema de las piernas, disestesias con déficit motor en miembros inferiores que, en dos casos, incluyó una cardiopatía que llevó a insuficiencia cardiaca irreversible. Este brote ocurrió entre julio de 1991 y junio de 1993; afectó selectivamente infantes de marina de la Escuela Naval Almirante Padilla en Cartagena de Indias. La metodología se centró en un estudio de casos y controles en el cual se sometió a cada grupo a un cuidadoso interrogatorio, examen clínico, medición por el laboratorio de metales pesados en sangre y orina de 24 horas y estudio de niveles de tiamina en muestras de suero; se analizaron cuatro biopsias de nervio sural y en el estudio postmortem de los fallecidos se puso especial atención a las alteraciones de miocardio. En muestras ambientales y biológicas, se analizó mercurio, plomo, arsénico y talio. Los resultados totalizan un grupo de 22 infantes de marina con un cuadro muy uniforme sobre todo por las manifestaciones de una neuropatía periférica nutricional, lo cual sumado a la cardiopatía fatal en dos pacientes, cuyo estudio tanto en microscopia de luz como electrónica, demostró cambios en todo compatibles con lo observado en beriberi, permiten que se considere que el problema de fondo reune las características del beriberi húmedo. Después de concluir que el problema tenía como fondo un origen nutricional basado, en primer lugar, en una falla de tiamina, se hicieron las recomendaciones y ajustes dietéticos indicados para estos casos con una respuesta inmediata y enteramente satisfactoria.

Mapping Investments and Published Outputs in Norovirus Research: A Systematic Analysis of Research Funded in the United States and United Kingdom During 1997-2013.

Science.gov (United States)

Head, Michael G; Fitchett, Joseph R; Lichtman, Amos B; Soyode, Damilola T; Harris, Jennifer N; Atun, Rifat

2016-02-01

Norovirus accounts for a considerable portion of the global disease burden. Mapping national or international investments relating to norovirus research is limited. We analyzed the focus and type of norovirus research funding awarded to institutions in the United States and United Kingdom during 1997-2013. Data were obtained from key public and philanthropic funders across both countries, and norovirus-related research was identified from study titles and abstracts. Included studies were further categorized by the type of scientific investigation, and awards related to vaccine, diagnostic, and therapeutic research were identified. Norovirus publication trends are also described using data from Scopus. In total, US and United Kingdom funding investment for norovirus research was £97.6 million across 349 awards; 326 awards (amount, £84.9 million) were received by US institutions, and 23 awards (£12.6 million) were received by United Kingdom institutions. Combined, £81.2 million of the funding (83.2%) was for preclinical research, and £16.4 million (16.8%) was for translational science. Investments increased from £1.7 million in 1997 to £11.8 million in 2013. Publication trends showed a consistent temporal increase from 48 in 1997 to 182 in 2013. Despite increases over time, trends in US and United Kingdom funding for norovirus research clearly demonstrate insufficient translational research and limited investment in diagnostics, therapeutics, or vaccine research. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

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 age (outpatient incidence = 25.6 per 1,000 person-years; community incidence = 152.2 per 1,000 person-years), followed by older adults aged >65 years (outpatient incidence = 7.8 per 1,000 person-years; community incidence = 75.8 per 1,000 person

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

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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

Replication of human noroviruses in stem cell-derived human enteroids

Science.gov (United States)

The major barrier to research and development of effective interventions for human noroviruses (HuNoVs) has been the lack of a robust and reproducible in vitro cultivation system. HuNoVs are the leading cause of gastroenteritis worldwide. We report successful cultivation of multiple HuNoV strains in...

A Gastroenteritis Outbreak Caused by Noroviruses in Greece

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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.

Intoxicación alimentaria por clostridium perfringens en el centro penitenciario cocori, cartago, costa rica, del 4 al 5 de septiembre del 2002

OpenAIRE

Espinoza, A; Arguedas, H; Asenjo, A

2004-01-01

Introducción El 5 de setiembre del 2002 el Centro Penitenciario Cocorí en Cartago, notificó al Sistema de Vigilancia del Ministerio de Salud, la presencia de 133 casos de diarrea. Ante esta situación, las autoridades de salud plantearon la investigación, para identificar los factores asociados a la presencia del brote. Material y métodos Mediante la revisión de los expedientes de los casos atendidos por diarrea en el Centro Penitenciario, se identificaron los que cumplieran con la siguiente d...

PROPAGACIÓN ASEXUAL DE AZUL DE MATA (Justicia tinctoria (OERST. D. N. GIBSON, FAM. ACANTHACEAE POR MEDIO DE ESTACAS

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Carlos A. Solís

2015-01-01

Full Text Available Se evaluó el efecto de dosis de ácido indolbutírico (0, 500, 1000 o 1500 ppm, la posición de donde se toma la estaca (basal, medial o terminal, el tamaño de la estaca (6, 10 o 14 cm, la ausencia o presencia de hojas, y el tipo de sustrato (arena de río, fibra de coco o carbón de granza de arroz, sobre el enraizamiento de estacas de azul de mata bajo ambiente protegido. Las variables evaluadas fueron el porcentaje de brotación y de enraizamiento, número de brotes, cantidad y longitud de raíces. Las estacas terminales presentaron los mayores valores para todas las variables, excepto porcentaje de enraizamiento: mayor número de brotes (17,5, longitud (0,17 y cantidad de raíces (0,65 que las estacas mediales y basales, lo que estaría asociado a una mayor velocidad de enraizamiento. Las dosis de AIB 1000 y 1500 ppm indujeron una mayor cantidad de raíces por estaca (8,40 y 9,24 respectivamente que las dosis menores. Hubo mayor porcentaje de enraizamiento con 1000 ppm de AIB (69% que sin ese compuesto (41%. Al utilizar estacas sin hojas aumentó la magnitud de cada una de esas variables. Con arena se obtuvo una mayor brotación aérea (96%, enraizamiento (92% y longitud de raíz (5,1 cm que con los otros sustratos. Las estacas de 14 cm presentaron consistentemente, mayor número de brotes (3,71, raíces más largas (3,56 cm y en mayor número (10,71 que las de 10 y 6 cm.

Urban outbreak of acute orally acquired Chagas disease in Táchira, Venezuela

OpenAIRE

Benítez, Jesús A.; Araujo, Benjamín; Contreras, Krisell; Rivas, Marianela; Ramírez, Pedro; Guerra, Watermo; Calderón, Noél; Terren, Carlo Ascaso; Barrera, Reggie; Rodríguez Morales, Alfonso Javier

2013-01-01

Aguda por vía oral adquirió la enfermedad de Chagas (AOACD) se ha convertido en una amenaza importante en algunos países de América del Sur [1,2]. Hasta marzo de 2013, al menos cuatro han reportado brotes de la enfermedad de Chagas aguda adquirida por vía oral, en concreto Brasil [3], Venezuela [4], Colombia [5] y Bolivia [6]. Los brotes también se están produciendo probablemente en Argentina y Ecuador, según algunos informes antiguos [2]. En Venezuela, ha habido por lo menos tres informes ep...

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.

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

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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.

EFECTO DE BIOFERTILIZANTES SOBRE LA TOLERANCIA DE BANANO A LA DESINFECCIÓN E INDUCCIÓN DE ORGANOGÉNESIS

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Gabriela Sandoval-Cancino

2013-01-01

Full Text Available El objetivo de este estudio fue evaluar el efecto de biofertilizantes y medios de cultivo sobre la tolerancia al establecimiento aséptico y la inducción de la organogénesis en banano. Se utilizaron explantes de hijuelos de dos genotipos de Musa cavendish AAA, cultivares ‘Clon Francés’ y ‘Clon Oaxaqueño’. Se evaluaron tres aplicaciones de biofertilizante (1 g de Glomus intraradices, 1 ml de la bacteria diazotrófica 11B y la interacción de ambos microorganismos y una sin biofertilizantes. Se sembraron los ápices en tres medios de cultivo: MS sin reguladores de crecimiento, MS adicionado con 22.2 μM de bencilaminopurina (BAP y MS adicionado con 11.4 μM de ácido indolacético (AIA y 22.2 μM de BAP. Se midieron las relaciones hídricas, el contenido de catalasa y peroxidasa, los explantes con brotes y los brotes por explante. En ambos clones se elevó la inducción de la organogénesis con la adición de BAP y por la biofertilización previa de los hijuelos. En el ‘Clon Oaxaqueño’ los tratamientos 6, 8 y 11 indujeron mayor organogénesis, con promedios entre 66 y 71 % de explantes con brotes y entre 3.16 y 2.28 brotes por explante. Para el ‘Clon Francés’ los tratamientos 8 y 9 elevaron la inducción de la organogénesis con promedios de 66 hasta 83 % de explantes con brotes y 1.83 a 2.16 brotes por explante. En ambos genotipos, los biofertilizantes propiciaron mayor porcentaje de supervivencia, mayor tolerancia a la oxidación y menor contaminación. En los dos genotipos, los tratamientos 1 (Glomus intraradices y 4 (Testigo produjeron menos estrés en las plantas.

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.; 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 incidence = 25.6 per 1,000 person-years; community incidence = 152.2 per 1,000 person-years), followed by older adults aged >65 years (outpatient incidence = 7.8 per 1,000 person-years; community incidence = 75.8 per 1,000 person

CULTIVO DE TEJIDOS EN Ficus carica CON MINIESTACAS

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Dora Mar\\u00EDa Flores-Mora

2009-01-01

brotes desarrollados, se inocularon y se empleó como medio base M&S (1962 completo, suplementado con 1,0; 0,5 y 0 mg/l de BAP. Para la etapa de enraizamiento, se implementaron dos tratamie ntos, M&S (1962 completo con 0,5 y 0 mg/l de AI B. Se obtuvo un 31,67 % de supervivencia y asepsia del material en la etapa de introducción y un promedio de tres brotes por explante al mes de incubación. El mayor promedio de brotes por explante se logró en el tratamiento con 1,0 mg/l de BAP y el mayor porcentaje de enraizamiento se obtuvo en el tratamiento sin regulador. Durante la fase de aclimatación, se logró un 100 % de supervivencia.

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.

Transmisión de Anaplasma marginale por garrapatas

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Kelly A. Brayton

2012-01-01

Full Text Available Anaplasma marginale, patógeno de distribución mundial, es transmitido por garrapatas Ixódidas. Comprender su complejo desarrollo dentro de la garrapata vector, permitirá la predicción de brotes y ofrecerá oportunidades para controlar su transmisión. En este trabajo se revisa su ciclo básico de desarrollo junto con los estudios recientes acerca de las diferencias de transmisión entre cepas, que delinean aspectos de la interacción patógeno - vector. Bacterias, virus o protozoarios transmitidos por artrópodos causan enfermedades severas, tanto en humanos como en animales. Las enfermedades infecciosas transmitidas por garrapatas, entre las que incluimos a la Anaplasmosis (A. marginale, babesiosis (Babesia bigemina, B. bovis, B. divergens y Theileriosis (Theileria annulata, T. parva, se encuentran entre las más importantes en el ámbito mundial, con pérdidas cercanas a los siete mil millones de dólares anualmente; y, a pesar de su impacto, permanecen escasamente bajo control, basado primordialmente en la aplicación de acaricidas, para interrumpir su transmisión. La aparición de garrapatas resistentes a múltiples sustancias acaricidas, representa una amenaza en este tipo de control y, como resultado, hay un resurgimiento de la investigación para el desarrollo de nuevas estrategias para su control. Nuevas opciones para prevenir la transmisión de patógenos de animales por garrapatas, será el resultado de entender las interacciones garrapata patógeno; proceso que culmina con el desarrollo de la infección y transmisión exitosa. En todos los casos de patógenos transmitidos por garrapatas, el desarrollo de la infección se realiza coordinamente a los momentos de adhesión y alimentación del vector sobre el animal. Esto sucede por la interdependencia en la señalización entre el patógeno y el vector al alimentarse y, por ello, será susceptible de intervención.

Chronic or accidental exposure of oysters to norovirus: is there any difference in contamination?

Science.gov (United States)

Ventrone, Iole; Schaeffer, Julien; Ollivier, Joanna; Parnaudeau, Sylvain; Pepe, Tiziana; Le Pendu, Jacques; Le Guyader, Françoise S

2013-03-01

Bivalve molluscan shellfish such as oysters may be contaminated by human pathogens. Currently, the primary pathogens associated with shellfish-related outbreaks are noroviruses. This study was conducted to improve understanding of oyster bioaccumulation when oysters were exposed to daily contamination or one accidental contamination event, i.e., different modes of contamination. Oysters were contaminated with two representative strains of norovirus (GI.1 and GII.3) and then analyzed with real-time reverse transcription PCR. Exposure to a repeated virus dose for 9 days (mimicking a growing area subjected to frequent sewage contamination) led to an additive accumulation that was not significantly different from that obtained when the same total dose of virus was added all at once (as may happen after accidental sewage discharge). Similarly, bioaccumulation tests performed with mixed strains revealed additive accumulation of both viruses. Depuration may not be efficient for eliminating viruses; therefore, to prevent contaminated shellfish from being put onto the market, continuous sanitary monitoring must be considered. All climatic events or sewage failures occurring in production areas must be recorded, because repeated low-dose exposure or abrupt events may lead to similar levels of accumulation. This study contributes to an understanding of norovirus accumulation in oysters and provides suggestions for risk management strategies.

Variations in status of preparation of personal protective equipment for preventing norovirus gastroenteritis in long-term care facilities for the elderly.

Science.gov (United States)

Fujiki, Saori; Ishizaki, Tatsuro; Nakayama, Takeo

2017-12-01

Residents of long-term care facilities are highly susceptible to norovirus gastroenteritis, and each facility is concerned about the need to implement norovirus infection control. Among control measures, personal protective equipment (PPE), such as disposable gloves and masks, plays a major role in reducing infectious spread. However, the preparation status of PPE in facilities before infection outbreaks has not been reported. The aim was to clarify the implementation status of preventive measures for norovirus gastroenteritis and the cost of preparing the necessary PPE in long-term care facilities. A questionnaire survey of facilities affiliated with the Kyoto Prefecture and Osaka Prefecture branches of the Japan Association of Geriatric Health Services Facilities was conducted. The survey items were the characteristics of the facility, whether preventive measures had been implemented for norovirus gastroenteritis from October through the following March in both 2009 and 2010, and the quantities and unit prices of PPE prepared for preventive measures. Twenty-six (11.2%) of 232 surveyed facilities (as of August 2011) answered the survey. Among them, 24 (92.3%) in 2009 and 25 (96.2%) in 2010 reported having implemented preventive measures for norovirus gastroenteritis, while 21 facilities (80.8%) in 2009 and 22 facilities (84.6%) in 2010 had prepared PPE. The median total cost for preparing the PPE needed for the preventive measures was US $2601 (range US $221-9192) in 2009 and US $3904 (range US $305-6427) in 2010. Although the results need careful interpretation because of the low response rate, most of the surveyed long-term care facilities had implemented preventive measures for norovirus gastroenteritis. However, the cost of preparing the PPE needed for the preventive measures varied among the facilities. © 2017 John Wiley & Sons, Ltd.

Evidence for asymptomatic norovirus infection transmission associated with swimming at a tropical beach

Science.gov (United States)

Swimming in fecally-contaminated natural waterbodies can result in gastrointestinal (GI) infections and associated symptoms. However, the pathogenic microorganisms responsible are often unidentified because studies nearly always rely on self-reported symptoms. Noroviruses have be...

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

International Nuclear Information System (INIS)

Hartmann, Erica M.; Colquhoun, David R.; Schwab, Kellogg J.; Halden, Rolf U.

2015-01-01

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

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.

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 phenot...

Transmission of norovirus among NBA players and staff, winter 2010-2011.

Science.gov (United States)

Desai, Rishi; Yen, Catherine; Wikswo, Mary; Gregoricus, Nicole A; Provo, Jace E; Parashar, Umesh D; Hall, Aron J

2011-12-01

In December 2010, 24 players and staff members from 13 National Basketball Association teams were affected with gastroenteritis symptoms. Four of 5 stool specimens from ill players and staff tested positive for norovirus genogroup II. We document evidence of transmission both within teams and, potentially, between teams in 2 instances.

Vomiting as a Symptom and Transmission Risk in Norovirus Illness: Evidence from Human Challenge Studies.

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Amy E Kirby

Full Text Available In the US, noroviruses are estimated to cause 21 million cases annually with economic losses reaching $2 billion. Outbreak investigations frequently implicate vomiting as a major transmission risk. However, little is known about the characteristics of vomiting as a symptom or the amount of virus present in emesis.Emesis samples and symptomology data were obtained from previous norovirus human challenge studies with GI.1 Norwalk virus, GII.2 Snow Mountain virus, and a pilot study with GII.1 Hawaii virus. Viral titers in emesis were determined using strain-specific quantitative RT-PCR. In all four studies, vomiting was common with 40-100% of infected subjects vomiting at least once. However, only 45% of subjects with vomiting also had diarrhea. Most of the emesis samples had detectable virus and the mean viral titers were 8.0 x 105 and 3.9 x 104 genomic equivalent copies (GEC/ml for GI and GII viruses, respectively (p = 0.02. Sample pH was correlated with GII.2 Snow Mountain virus detection.Half of all subjects with symptomatic infection experienced vomiting and the average subject shed 1.7 x 108 GEC in emesis. Unlike shedding through stool, vomiting is more likely to result in significant environmental contamination, leading to transmission through fomites and airborne droplets. This quantitative data will be critical for risk assessment studies to further understand norovirus transmission and develop effective control measures. The correlation between sample pH and virus detection is consistent with a single site of virus replication in the small intestine and stomach contents becoming contaminated by intestinal reflux. Additionally, the frequency of vomiting without concurrent diarrhea suggests that epidemiology studies that enroll subjects based on the presence of diarrhea may be significantly underestimating the true burden of norovirus disease.

Norovirus Epidemiology in Africa: A Review.

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Janet Mans

Full Text Available Norovirus (NoV is recognised as a leading cause of gastroenteritis worldwide across all age groups. The prevalence and diversity of NoVs in many African countries is still unknown, although early sero-prevalence studies indicated widespread early infection. Reports on NoVs in Africa vary widely in terms of study duration, population groups and size, inclusion of asymptomatic controls, as well as genotyping information. This review provides an estimate of NoV prevalence and distribution of genotypes of NoVs in Africa. Inclusion criteria for the review were study duration of at least 6 months, population size of >50 and diagnosis by RT-PCR. As regions used for genotyping varied, or genotyping was not always performed, this was not considered as an inclusion criteria. A literature search containing the terms norovirus+Africa yielded 74 publications. Of these 19 studies from 14 out of the 54 countries in Africa met the inclusion criteria. Data from studies not meeting the inclusion criteria, based on sample size or short duration, were included as discussion points. The majority of studies published focused on children, under five years of age, hospitalised with acute gastroenteritis. The mean overall prevalence was 13.5% (range 0.8-25.5% in children with gastroenteritis and 9.7% (range 7-31% in asymptomatic controls, where tested. NoV GII.4 was the predominant genotype identified in most of the studies that presented genotyping data. Other prevalent genotypes detected included GII.3 and GII.6. In conclusion, NoV is a common pathogen in children with diarrhoea in Africa, with considerable carriage in asymptomatic children. There is however, a paucity of data on NoV infection in adults.

High pressure treatment of human norovirus-like particles: factors affecting destruction efficacy

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Human norovirus (HuNoV) is the leading cause of foodborne diseases worldwide. High pressure processing (HPP) is considered a promising non-thermal technology to inactivate viral pathogens in foods. However, the effectiveness of HPP on inactivating HuNoV remains poorly understood because it cannot be...

Waterborne gastroenteritis outbreak at a scouting camp caused by two norovirus genogroups: GI and GII.

Science.gov (United States)

ter Waarbeek, Henriëtte L G; Dukers-Muijrers, Nicole H T M; Vennema, Harry; Hoebe, Christian J P A

2010-03-01

A cross-border gastroenteritis outbreak at a scouting camp was associated with drinking water from a farmer's well. A retrospective cohort study was performed to identify size and source of the outbreak, as well as other characteristics. Epidemiological investigation included standardized questionnaires about sex, age, risk exposures, illness and family members. Stool and water (100mL) samples were analyzed for bacteria, viruses and parasites. Questionnaires were returned by 84 scouts (response rate 82%), mean age of 13 years. The primary attack rate was 85% (diarrhoea and/or vomiting). Drinking water was the strongest independent risk factor showing a dose-response effect with 50%, 75%, 75%, 93% and 96% case prevalence for 0, 1, 2-3, 4-5 and >5 glasses consumed, respectively. Norovirus (GI.2 Southampton and GII.7 Leeds) was detected in 51 stool specimens (75%) from ill scouts. Water analysis showed fecal contamination, but no norovirus. The secondary attack rate was 20%. This remarkable outbreak was caused by a point-source infection with two genogroups of noroviruses most likely transmitted by drinking water from a well. Finding a dose-response relationship was striking. Specific measures to reduce the risk of waterborne diseases, outbreak investigation and a good international public health network are important.

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Part III. Virus Detection by RT-qPCR

Science.gov (United States)

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. The viral ribonucleic acid (RNA) from water sample concentrates is extracted and tested for enterovirus and norovirus RNA using reverse transcription-quantitative PCR (RT-qPCR). V...

Research on the contamination levels of norovirus in food facilities using groundwater in South Korea, 2015-2016.

Science.gov (United States)

Lee, Jeong Su; Joo, In Sun; Ju, Si Yeon; Jeong, Min Hee; Song, Yun-Hee; Kwak, Hyo Sun

2018-09-02

Norovirus (NoV) is a major pathogenic virus that is responsible for foodborne and waterborne gastroenteritis outbreaks. Groundwater is an important source of drinking water and is used in agriculture and food manufacturing processes. This study investigated norovirus contamination of groundwater treatment systems at 1360 sites in seven metropolitan areas and nine provinces in 2015-2016. Temperature, pH, residual chlorine, and turbidity content were assessed to analyze the water quality. In 2015, six sites were positive for the presence of NoV (0.88%) and in 2016, two sites were positive (0.29%); in total, NoV was detected in 8 of the 1360 sample sites (0.59%) investigated. Identified genotypes of NoV in groundwater included GI.5, 9 and GII.4, 6, 13, 17, and 21. GII.17 was the most prevalent genotype in treated groundwater used in the food industry. This dominance of GII.17 was corroborated by NoV infection outbreak cases and the results of a survey of coastal waters in South Korea in 2014-2015. Although a low detection rate was observed in this study, NoV is a pathogen that can spread extensively. Therefore, it is necessary to periodically monitor levels of norovirus which is responsible for food poisoning in groundwater. This is a first report to reveal epidemic genotype shift of norovirus in groundwater treatment system of food facilities in South Korea. Our results may contribute to the enhancement of public health and sanitary conditions by providing molecular epidemiological information on groundwater NoV. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluation of methods using celite to concentrate norovirus, adenovirus and enterovirus from wastewater

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Enteroviruses, noroviruses and adenoviruses are among the most common viruses infecting humans worldwide. These viruses are shed in the feces of infected individuals and can accumulate in wastewater. Therefore, wastewater is a source of a potentially diverse group of enteric viru...

Series of Norovirus Outbreaks Caused by Consumption of Green Coral Lettuce, Denmark, April 2016

DEFF Research Database (Denmark)

Müller, Luise; Rasmussen, Lasse Dam; Jensen, Tenna

2016-01-01

In early April 2016, an unusual high number of point-source outbreaks of gastrointestinal disease were reported to occur in Denmark. Outbreaks were individually investigated. Two analytical studies were performed. Patient stool samples collected and analysed; positive stool samples were sequenced...... over the polymerase and/or capsid gene areas. Implicated lettuce heads were collected and analysed for the presence of norovirus. Foods were traced-back and traced-forward and international alert systems applied. A total of 23 linked point-source outbreaks occurred over the course of one week. Fresh...... green coral lettuce (Lollo Bionda lettuce) had been consumed in all settings. In a cohort study including 234 participants a dish containing green lettuce was associated with illness. Norovirus of Genogroup I (GI) was detected in samples from 28 patients comprising eight of the outbreaks. Sequencing...

Potential risk of norovirus infection due to the consumption of "ready to eat" food.

Science.gov (United States)

Serracca, Laura; Rossini, Irene; Battistini, Roberta; Goria, Maria; Sant, Serena; De Montis, Gabriella; Ercolini, Carlo

2012-09-01

In this study, we investigated the presence of enteric viruses such as norovirus (NoV), hepatitis A virus (HAV), hepatitis E virus (HEV), and adenovirus (HAdV), in vegetables available on the Italian markets. For this aim, 110 national and international "ready to eat" samples were collected and analyzed by biomolecular tests and positive samples were confirmed by sequencing. All samples (100 %) were negative for HAV, HEV, and HAdV, while 13.6 % (15/110) were positive for NoV. Actually there is not a formal surveillance system for NoV infections in Italy but we clearly demonstrated a potential risk associated with the consumption of "ready to eat" vegetables. This study confirmed for the first time in Italy the presence of norovirus in semi-dried tomatoes by PCR technique.

Evaluation of a rapid method for recovery of norovirus and hepatitis A virus from oysters and blue mussels

DEFF Research Database (Denmark)

Uhrbrand, Katrine; Myrmel, Mette; Maunula, Leena

2010-01-01

Foodborne outbreaks caused by noroviruses (NoVs) and hepatitis A virus (HAV) are often linked to consumption of contaminated shellfish. The objective of this study was to identify an appropriate virus recovery method for real-time reverse transcriptase (RT)-PCR detection and subsequently to evalu......Foodborne outbreaks caused by noroviruses (NoVs) and hepatitis A virus (HAV) are often linked to consumption of contaminated shellfish. The objective of this study was to identify an appropriate virus recovery method for real-time reverse transcriptase (RT)-PCR detection and subsequently...

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

Science.gov (United States)

2012-04-02

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 866 [Docket No. FDA-2012-N-0165] Medical Devices; Immunology and Microbiology Devices; Classification of Norovirus Serological Reagents; Correction AGENCY: Food and Drug Administration, HHS. ACTION: Final rule; correction...

Additional value of typing Noroviruses in gastroenteritis outbreaks in Amsterdam, The Netherlands

NARCIS (Netherlands)

Koek, A. G.; Bovée, L. P. M. J.; van den Hoek, J. A. R.; Bos, A. J.; Bruisten, S. M.

2006-01-01

In Amsterdam, 17 of the 55 gastroenteritis (GI) outbreaks reported from January 2002 to May 2003 were confirmed to be caused by noroviruses (NV). In this study, we describe the molecular epidemiology of a group of nine outbreaks associated with a catering firm and two outbreaks, 5 months apart, in

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.

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.

77 FR 14272 - Medical Devices; Immunology and Microbiology Devices; Classification of Norovirus Serological...

Science.gov (United States)

2012-03-09

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 866 [Docket No. FDA-2012-N-0165] Medical Devices; Immunology and Microbiology Devices; Classification of Norovirus... AND MICROBIOLOGY DEVICES 0 1. The authority citation for 21 CFR part 866 continues to read as follows...

High pressure treatment of human norovirus virus-like particles: factors affecting destruction efficacy

Science.gov (United States)

Human norovirus (NoV) accounts for more than 90% of nonbacterial gastroenteritis. To date, the efficacy of human NoV inactivation interventions cannot be accurately evaluated because the virus is nonculturable. In this study, we aimed to estimate inactivation of human NoV by high pressure processing...

Use of Low-Density DNA Microarrays and Photopolymerization for Genotyping Foodborne-Associated Noroviruses

Science.gov (United States)

Human noroviruses cause up to 21 million cases of foodborne disease in the United States annually and are the most common cause of acute gastroenteritis in industrialized countries. To reduce the burden of foodborne disease associated with viruses, the use of low density DNA microarrays in conjunct...

Efecto de la aplicación de Chlorpro p ham en el brotamiento de tubérculos de olluco (Ullucus tuberosus L. en condiciones de almacén

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Isaac Aliaga

2011-01-01

Full Text Available Se evaluó el efecto de Chlorpropham sobre el brotamiento de tubérculos de olluco ( U llucus tuberosum L. Variedad Tarmeño durante el almacenamiento a 15 °C y HR de 85 %; los tratamientos fueron 0, 5, 10, 20 y 30 mg de Chlorproph am por kg de tubérculo, e n un diseño completamente al azar con 4 rep eticiones. A los 60 días de almacenamiento l a longitud de brotes para el testigo sin Chlorpropham fue de 9.63 cm y para los tratamientos con Chlorpropham desde 0. 22 hasta 0 .71 cm. A los 90 días la longitud de los brotes se mantuvieron iguales y algunos bro tes empezaron a secarse, a excepción del testigo donde se incrementaron de tamaño de 15 a 20 cm. A los 90 días de almacenamiento la pérdida de peso para los tratamientos con Chlorpropham fue en promedio de 21 % y para el testigo de 37.35 %. Todos los trata mientos de Chlorpropham mostraron un menor número de brotes por tubérculo, menor longitud de brotes, menor número de tubérculos con brotes y menor pérdida de peso; con un p<0 . 05, la prueba de Duncan mostró que no existe diferencias significativa entre l os tratamientos con Chlorpropham para las variables evaluadas, pero si diferencias significativas con el tratamiento testigo.

Naturally occurring flavonoids against human norovirus surrogates.

Science.gov (United States)

Su, Xiaowei; D'Souza, Doris H

2013-06-01

Naturally occurring plant-derived flavonoids are reported to have antibacterial, antiviral, and pharmacological activities. The objectives of this study were to determine the antiviral effects of four flavonoids (myricetin, L-epicatechin, tangeretin, and naringenin) on the infectivity of food borne norovirus surrogates after 2 h at 37 °C. The lab-culturable surrogates, feline calicivirus (FCV-F9) at titers of ~7 log₁₀ PFU/ml (high titer) or ~5 log₁₀ PFU/ml (low titer) and murine norovirus (MNV-1) at ~5 log₁₀ PFU/ml, were mixed with equal volumes of myricetin, L-epicatechin, tangeretin, or naringenin at concentrations of 0.5 or 1 mM, and incubated for 2 h at 37 °C. Treatments of viruses were neutralized in cell culture medium containing 10 % heat-inactivated fetal bovine serum, serially diluted, and plaque assayed. Each treatment was replicated thrice and assayed in duplicate. FCV-F9 (low titer) was not found to be reduced by tangeretin or naringenin, but was reduced to undetectable levels by myricetin at both concentrations. Low titer FCV-F9 was also decreased by 1.40 log₁₀ PFU/ml with L-epicatechin at 0.5 mM. FCV-F9 at high titers was decreased by 3.17 and 0.72 log₁₀ PFU/ml with myricetin and L-epicatechin at 0.5 mM, and 1.73 log10 PFU/ml with myricetin at 0.25 mM, respectively. However, MNV-1 showed no significant inactivation by the four tested treatments. The antiviral effects of the tested flavonoids are dependent on the virus type, titer, and dose. Further research will focus on understanding the antiviral mechanism of myricetin and L-epicatechin.

Estudio de un brote epidémico de tos ferina en Castellón

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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.

Rapid detection of hepatitis A virus and murine norovirus in hemocytes of contaminated oysters

Science.gov (United States)

The human enteric pathogens, hepatitis A virus and human norovirus, have been shown to contaminate molluscan shellfish and cause foodborne disease in consumers. Rapid viral extraction methods are needed to replace current time consuming methods, which use whole oysters or dissected tissues. In our ...

Norovirus GII.17 Outbreak Linked to an Infected Post-Symptomatic Food Worker in a French Military Unit Located in France.

Science.gov (United States)

Sanchez, Marc-Antoine; Corcostégui, Simon-Pierre; De Broucker, Charles-Arnaud; Cabre, Olivier; Watier-Grillot, Stéphanie; Perelle, Sylvie; Ambert-Balay, Katia; Pommier de Santi, Vincent

2017-06-01

In February 2016, an outbreak of gastroenteritis occurred in a French military unit located in Poitiers, France. Attack rate was of 34% (103/300). A case-control study identified association between illness and cake consumption. Stool samples were tested positive for Norovirus GII.17 for one patient and one post-symptomatic food worker (FW). The FW presented vomiting one day before cake preparation. The NoV strain was probably spread through food worker hand contact. Prevention of Norovirus foodborne outbreaks implies new guidelines for FWs management in France and Europe.

Noroviruses associated with acute gastroenteritis in a children's day care facility in Rio de Janeiro, Brazil

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Gallimore C.I.

2004-01-01

Full Text Available Noroviruses (Norwalk-like viruses are an important cause of gastroenteritis worldwide. They are the most common cause of outbreaks of gastroenteritis in the adult population and occur in nursing homes for the elderly, geriatric wards, medical wards, and in hotel and restaurant settings. Food-borne outbreaks have also occurred following consumption of contaminated oysters. This study describes the application of a reverse transcription-polymerase chain reaction (RT-PCR assay using random primers (PdN6 and specific Ni and E3 primers, directed at a small region of the RNA-dependent RNA polymerase-coding region of the norovirus genome, and DNA sequencing for the detection and preliminary characterisation of noroviruses in outbreaks of gastroenteritis in children in Brazil. The outbreak samples were collected from children <5 years of age at the Bertha Lutz children's day care facility at Oswaldo Cruz Foundation (Fiocruz, Rio de Janeiro, that occurred between 1996 and 1998, where no pathogen had been identified. At the Bertha Lutz day care center facility, only Fiocruz's employee children are provided for, and they come from different social, economic and cultural backgrounds. Three distinct genogroup II strains were detected in three outbreaks in 1997/98 and were most closely related to genotypes GII-3 (Mexico virus and GII-4 (Grimsby virus, both of which have been detected in paediatric and adult outbreaks of gastroenteritis worldwide.

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

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

Inactivation of human norovirus in contaminated oysters and clams by high-hydrostatic pressure

Science.gov (United States)

Human norovirus (NoV) is the most frequent causative agent of foodborne disease associated with shellfish consumption. In this study, the effect of high-hydrostatic pressure (HHP) on inactivation of NoV was determined. Genogroup I.1 (GI.1) or Genogroup II.4 (GII.4) NoV were inoculated into oyster ho...

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

Evaluation of air samplers and filter materials for collection and recovery of airborne norovirus.

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Uhrbrand, K; Koponen, I K; Schultz, A C; Madsen, A M

2018-04-01

The aim of this study was to identify the most efficient sampling method for quantitative PCR-based detection of airborne human norovirus (NoV). A comparative experiment was conducted in an aerosol chamber using aerosolized murine norovirus (MNV) as a surrogate for NoV. Sampling was performed using a nylon (NY) filter in conjunction with four kinds of personal samplers: Gesamtstaubprobenahme sampler (GSP), Triplex-cyclone sampler (TC), 3-piece closed-faced Millipore cassette (3P) and a 2-stage NIOSH cyclone sampler (NIO). In addition, sampling was performed using the GSP sampler with four different filter types: NY, polycarbonate (PC), polytetrafluoroethylene (PTFE) and gelatine (GEL). The sampling efficiency of MNV was significantly influenced by both sampler and filter type. The GSP sampler was found to give significantly (P airborne NoV. The identification of a suitable NoV air sampler is an important step towards studying the association between exposure to airborne NoV and infection. © 2017 The Society for Applied Microbiology.

Content Analysis of Vomit and Diarrhea Cleanup Procedures To Prevent Norovirus Infections in Retail and Food Service Operations.

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Chao, Morgan G; Dubé, Anne-Julie; Leone, Cortney M; Moore, Christina M; Fraser, Angela M

2016-11-01

Human noroviruses are the leading cause of foodborne disease in the United States, sickening 19 to 21 million Americans each year. Vomit and diarrhea are both highly concentrated sources of norovirus particles. For this reason, establishing appropriate cleanup procedures for these two substances is critical. Food service establishments in states that have adopted the 2009 or 2013 U.S. Food and Drug Administration Food Code are required to have a program detailing specific cleanup procedures. The aim of our study was to determine the alignment of existing vomit and diarrhea cleanup procedures with the 11 elements recommended in Annex 3 of the 2011 Supplement to the 2009 Food Code and to determine their readability and clarity of presentation. In July 2015, we located vomit and diarrhea cleanup procedures by asking Norovirus Collaborative for Outreach, Research, and Education stakeholders for procedures used by their constituency groups and by conducting a Google Advanced Search of the World Wide Web. We performed content analysis to determine alignment with the recommendations in Annex 3. Readability and clarity of presentation were also assessed. A total of 38 artifacts were analyzed. The mean alignment score was 7.0 ± 1.7 of 11 points; the mean clarity score was 6.7 ± 2.5 of 17 points. Only nine artifacts were classified as high clarity, high alignment. Vomit and diarrhea cleanup procedures should align with Annex 3 in the Food Code and should, as well, be clearly presented; yet, none of the artifacts completely met both conditions. To reduce the spread of norovirus infections in food service establishments, editable guidelines are needed that are aligned with Annex 3 and are clearly written, into which authors could insert their facility-specific information.

A norovirus outbreak triggered by copper intoxication on a coach trip from the Netherlands to Germany, April 2010.

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Hoefnagel, J; van de Weerdt, Dh; Schaefer, O; Koene, R

2012-03-01

We report an unusual outbreak of norovirus infection on a coach trip. Overall, 30 of 40 people (including drivers and crew) developed nausea, vomiting and/or diarrhoea, 11 of them on the first day of the trip. The incidence epidemic curve showed a first peak on Day 1 and a second on Day 4. Nine passengers were hospitalised with gastrointestinal symptoms. Norovirus was found in stool samples from two patients, but the infection could not explain the first peak in the epidemic curve only a few hours after departure. Interviews with the passengers and an inspection of the coach and its water supply implicated the water used for coffee and tea as the potential source. Microbiological investigations of the water were negative, but chemical analysis showed a toxic concentration of copper. Blood copper levels as well as renal and liver function were determined in 28 of the 32 passengers who had been exposed to the water. One passenger who did not have gastrointestinal symptoms had an elevated copper level of 25.9 μmol/L, without loss of liver or renal function. It is likely that the spread of norovirus was enhanced because of vomiting of one of the passengers due to copper intoxication.

Phylodynamic reconstruction reveals norovirus GII.4 epidemic expansions and their molecular determinants.

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J Joukje Siebenga

2010-05-01

Full Text Available Noroviruses are the most common cause of viral gastroenteritis. An increase in the number of globally reported norovirus outbreaks was seen the past decade, especially for outbreaks caused by successive genogroup II genotype 4 (GII.4 variants. Whether this observed increase was due to an upswing in the number of infections, or to a surveillance artifact caused by heightened awareness and concomitant improved reporting, remained unclear. Therefore, we set out to study the population structure and changes thereof of GII.4 strains detected through systematic outbreak surveillance since the early 1990s. We collected 1383 partial polymerase and 194 full capsid GII.4 sequences. A Bayesian MCMC coalescent analysis revealed an increase in the number of GII.4 infections during the last decade. The GII.4 strains included in our analyses evolved at a rate of 4.3-9.0x10(-3 mutations per site per year, and share a most recent common ancestor in the early 1980s. Determinants of adaptation in the capsid protein were studied using different maximum likelihood approaches to identify sites subject to diversifying or directional selection and sites that co-evolved. While a number of the computationally determined adaptively evolving sites were on the surface of the capsid and possible subject to immune selection, we also detected sites that were subject to constrained or compensatory evolution due to secondary RNA structures, relevant in virus-replication. We highlight codons that may prove useful in identifying emerging novel variants, and, using these, indicate that the novel 2008 variant is more likely to cause a future epidemic than the 2007 variant. While norovirus infections are generally mild and self-limiting, more severe outcomes of infection frequently occur in elderly and immunocompromized people, and no treatment is available. The observed pattern of continually emerging novel variants of GII.4, causing elevated numbers of infections, is therefore a

Aumento de consultas en atención primaria por infección respiratoria de vías altas y por fiebre coincidiendo con la gripe (H1N1 2009

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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.

Acciones para el control de un brote de transmisión local de paludismo introducido en Santiago de Cuba Actions for the control of a local transmission outbreak of malaria introduced in Santiago de Cuba

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Sergio C Miranda Reyes

2009-06-01

Full Text Available Se realizó un estudio descriptivo y transversal sobre el brote de paludismo introducido en el municipio de Santiago de Cuba durante el 2006, para lo cual se efectuó una investigación epidemiológica de campo, que constó de 4 etapas: observación, hipótesis, verificación, conclusiones y aplicaciones prácticas. El universo estuvo constituido por las viviendas, locales y criaderos naturales de las localidades estratificadas. Sigua es una comunidad rural donde coexistían criaderos naturales y un hotel - hospital dedicado en aquel momento a la “Operación Milagro”. Inicialmente se notificaron 2 casos sospechosos de leptospirosis, luego se observó que otras 10 personas de la comunidad habían sido ingresadas con diagnóstico de procesos infecciosos y el 11 de febrero se confirmaron 4 casos de paludismo por Plasmodium vivax. Las acciones sobre la vía de transmisión incluyeron tratamiento adulticida extradomiciliario e intradomiciliario y otras. La campaña promocional logró, a través de la acción comunitaria, la eliminación de elementos ambientales de riesgo y contribuyó a la vigilancia activa de pacientes en estado febril. Entre la notificación del brote y la fecha de inicio de síntomas del último caso confirmado transcurrieron 12 días.A descriptive and cross-sectional study on the outbreak of malaria introduced in Santiago de Cuba municipality during 2006 was carried out. Thus, a field epidemiological investigation was conducted consisting of 4 stages: observation, hypothesis, verification, conclusions and practical applications. Housings, premises and natural hatcheries of stratified areas were studied. Sigua is a rural community where natural hatcheries and a hotel-hospital used in that moment for the "Operación Milagro" coexisted. Initially 2 suspicious cases of leptospirosis were notified, then 10 other people of the community had been admitted with a diagnosis of infectious processes, and in February 11th, 4 cases of

Method 1615: Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR

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Version 1.1 - Enteroviruses and noroviruses that may be present in environmental or finished drinking waters are concentrated by passage through electropositive filters. Viruses are eluted from the filters with a beef extract reagent and concentrated using organic flocculation....

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

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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.

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

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...

76 FR 65200 - Risk Assessment on Norovirus in Bivalve Molluscan Shellfish: Request for Comments and for...

Science.gov (United States)

2011-10-20

... transmission of norovirus from infected or ill food workers in food manufacturing or retail establishments to... Molluscan Shellfish Contamination Levels During Food Preparation and Bivalve Molluscan Shellfish Consumption... and other factors influencing bivalve molluscan shellfish contamination levels during food preparation...

Human norovirus inactivation in oysters by high hydrostatic pressure processing: A randomized double-blinded study

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This randomized, double-blinded, clinical trial assessed the effect of high hydrostatic pressure processing (HPP) on genogroup I.1 human norovirus (HuNoV) inactivation in virus-seeded oysters when ingested by subjects. The safety and efficacy of HPP treatments were assessed in three study phases wi...

Detection and genetic characterization of norovirus strains circulating among infants and children with acute gastroenteritis in Japan during 2004-2005.

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Phan, Tung Gia; Takanashi, Sayaka; Kaneshi, Kunio; Ueda, Yuichi; Nakaya, Shigekazu; Nishimura, Shuichi; Sugita, Kumiko; Nishimura, Tadashi; Yamamoto, Atsuko; Yagyu, Fumihiro; Okitsu, Shoko; Maneekarn, Niwat; Ushijima, Hiroshi

2006-01-01

A total of 752 fecal specimens collected during the period of July 2004 to June 2005 from infants and children with acute gastroenteritis from four different regions (Maizuru, Tokyo, Sapporo, and Osaka) of Japan were tested for the presence of norovirus by RT-PCR. It was found that 139 (18.5%) fecal specimens were positive for norovirus. Norovirus infection was detected almost all year round with the highest prevalence in January. Norovirus GII was the most predominant genogroup (98.6%; 137 of 139). The genotypes detected in this study were GI/1, GII/1, GII/3, GII/4, and GII/6. Of these, NoV GII/4 (known as the Lordsdale virus cluster) was re-emerging and became the leading genotype (77.7%). Meanwhile, the incidence of NoV GII/3 (known as the Arg320 virus cluster) has dropped rapidly, accounting for only 15.8%. Another interesting feature of the study was the identification of Picton03/AU-like recombinant NoV for the first time in Japan. Based on the genetic analysis, it was interesting to note that NoV GII/4 in 2004-2005 made a distinct cluster in comparison to other NoV GII/4 circulating in 2002-2003 and 2003-2004. Of note, "new recombinant variant designated GIIb" within NoV GII/3, which was first detected in Saga City, Japan in 2003-2004 in only one case, had increased, spreading widely in Japan and representing 45.5% (10 of 22). Further epidemiological studies should be conducted to determine whether this new recombinant variant strain will be dominant in Japan in the coming year.

Brote epidémico por Salmonella richmond en Castellón, España Epidemic outbreak caused by Salmonella richmond in Castellón, España

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María Rosario Pac Sa

1998-02-01

Full Text Available Se efectuó un estudio de casos y controles para investigar un brote de gastroenteritis aguda declarado en un destacamento militar situado en una zona rural de Castellón, España. El objetivo del estudio fue conocer las causas del brote y adoptar medidas de control. En total se incluyó a 135 hombres de los 153 que componían dicho destacamento. Entre el 9 y el 11 de agosto de 1993 se notificaron 45 casos, cuya media de edad fue de 19,2 ± 1,5 años. La tasa de ataque fue de 33,3%. En el cuadro clínico predominaron diarreas (76%, vómitos (67%, náuseas (67% y dolor abdominal (28%. La mediana de la duración de los síntomas fue un día y la del período de incubación, 33 horas. Solo se hospitalizó a un paciente y la evolución de todos los afectados fue buena. En cinco de 14 coprocultivos realizados se aisló Salmonella richmond (6,7:y:1,2. También se detectó una asociación entre el consumo de agua de una acequia, que discurría próxima al campamento, y la enfermedad. Mediante un modelo de regresión logística se constató que el consumo del agua de esta fuente permaneció asociado con el estado de caso después de ajustar la asociación según la edad y el consumo de distintos alimentos (razón de posibilidades = 96,5; intervalo de confianza de 95%: 11,4 ­ 814,4. El riesgo de padecer la enfermedad aumentó con la cantidad de agua ingerida (prueba de tendencia X² = 65,4; P A case-control study was carried out to investigate an outbreak of acute gastroenteritis among a military detachment stationed in a rural area of Castellón, España. The purpose of the study was to determine the causes of the outbreak and develop control measures. Of the 153 men in the detachment, 135 were included in the study. Between 9 and 11 August 1993, 45 cases were reported; the patients' average age was 19.2 ± 1.5 years. The attack rate was 33.3%. The clinical picture was dominated by the following symptoms: diarrhea (76%, vomiting (67%, nausea (67%, and

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

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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.

Conformational Occlusion of Blockade Antibody Epitopes, a Novel Mechanism of GII.4 Human Norovirus Immune Evasion.

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Lindesmith, Lisa C; Mallory, Michael L; Debbink, Kari; Donaldson, Eric F; Brewer-Jensen, Paul D; Swann, Excel W; Sheahan, Timothy P; Graham, Rachel L; Beltramello, Martina; Corti, Davide; Lanzavecchia, Antonio; Baric, Ralph S

2018-01-01

Extensive antigenic diversity within the GII.4 genotype of human norovirus is a major driver of pandemic emergence and a significant obstacle to development of cross-protective immunity after natural infection and vaccination. However, human and mouse monoclonal antibody studies indicate that, although rare, antibodies to conserved GII.4 blockade epitopes are generated. The mechanisms by which these epitopes evade immune surveillance are uncertain. Here, we developed a new approach for identifying conserved GII.4 norovirus epitopes. Utilizing a unique set of virus-like particles (VLPs) representing the in vivo -evolved sequence diversity within an immunocompromised person, we identify key residues within epitope F, a conserved GII.4 blockade antibody epitope. The residues critical for antibody binding are proximal to evolving blockade epitope E. Like epitope F, antibody blockade of epitope E was temperature sensitive, indicating that particle conformation regulates antibody access not only to the conserved GII.4 blockade epitope F but also to the evolving epitope E. These data highlight novel GII.4 mechanisms to protect blockade antibody epitopes, map essential residues of a GII.4 conserved epitope, and expand our understanding of how viral particle dynamics may drive antigenicity and antibody-mediated protection by effectively shielding blockade epitopes. Our data support the notion that GII.4 particle breathing may well represent a major mechanism of humoral immune evasion supporting cyclic pandemic virus persistence and spread in human populations. IMPORTANCE In this study, we use norovirus virus-like particles to identify key residues of a conserved GII.4 blockade antibody epitope. Further, we identify an additional GII.4 blockade antibody epitope to be occluded, with antibody access governed by temperature and particle dynamics. These findings provide additional support for particle conformation-based presentation of binding residues mediated by a particle

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

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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...

Detection of norovirus virus-like particles using a surface plasmon resonance-assisted fluoroimmunosensor optimized for quantum dot fluorescent labels.

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Ashiba, Hiroki; Sugiyama, Yuki; Wang, Xiaomin; Shirato, Haruko; Higo-Moriguchi, Kyoko; Taniguchi, Koki; Ohki, Yoshimichi; Fujimaki, Makoto

2017-07-15

A highly sensitive biosensor to detect norovirus in environment is desired to prevent the spread of infection. In this study, we investigated a design of surface plasmon resonance (SPR)-assisted fluoroimmunosensor to increase its sensitivity and performed detection of norovirus virus-like particles (VLPs). A quantum dot fluorescent dye was employed because of its large Stokes shift. The sensor design was optimized for the CdSe-ZnS-based quantum dots. The optimal design was applied to a simple SPR-assisted fluoroimmunosensor that uses a sensor chip equipped with a V-shaped trench. Excitation efficiency of the quantum dots, degree of electric field enhancement by SPR, and intensity of autofluorescence of a substrate of the sensor chip were theoretically and experimentally evaluated to maximize the signal-to-noise ratio. As the result, an excitation wavelength of 390nm was selected to excite SPR on an Al film of the sensor chip. The sandwich assay of norovirus VLPs was performed using the designed sensor. Minimum detectable concentration of 0.01ng/mL, which corresponds to 100 virus-like particles included in the detection region of the V-trench, was demonstrated. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Antiviral activity of Ecasol against feline calicivirus, a surrogate of human norovirus

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Yogesh Chander

2012-12-01

Full Text Available Summary: Human norovirus (NoV is a major cause of acute gastroenteritis in closed settings such as hospitals, hotels and cruise ships. The virus survives on inanimate surfaces for extended periods of time, and environmental contamination has been implicated in its transmission. The disinfection of contaminated areas is important in controlling the spread of NoV infections. Neutral solutions of electrochemically activated (ECA-anolyte have been shown to be powerful disinfectants against a broad range of bacterial pathogens. The active chemical ingredient is hypochlorous acid (HOCl, which is registered as an approved food contact surface sanitizer in the United States by the Environmental Protection Agency, pursuant to 40 CFR 180.940. We evaluated the antiviral activity of Ecasol (an ECA-anolyte against feline calicivirus (FCV, a surrogate of NoV. FCV dried on plastic surfaces was exposed to Ecasol for 1, 2, or 5 min. After exposure to Ecasol, the virus titers were compared with untreated controls to determine the virus inactivation efficacy after different contact times. Ecasol was found to decrease the FCV titer by >5 log10 within 1 min of contact, indicating its suitability for inactivation of NoV on surfaces. Keywords: Ecasol, ECA-anolyte, Trustwater, Electrochemical activation, Norovirus, Feline calicivirus, Fomites

Llama nanoantibodies with therapeutic potential against human norovirus diarrhea.

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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.

A universal primer-independent next-generation sequencing approach for investigations of norovirus outbreaks and novel variants

DEFF Research Database (Denmark)

Fonager, Jannik; Stegger, Marc; Rasmussen, Lasse Dam

2017-01-01

Norovirus (NoV) is the most common cause of non-bacterial gastroenteritis and is a major agent associated with outbreaks of gastroenteritis. Conventional molecular genotyping analysis of NoV, used for the identification of transmission routes, relies on standard typing methods (STM) by Sanger...

Sensitive genotyping of foodborne-associated human noroviruses and hepatitis A virus using an array-based platform

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The viral pathogens, human norovirus (NoV) and hepatitis A virus (HAV), are significant contributors of foodborne associated outbreaks. To develop a typing tool for foodborne viruses, a focused, low-density DNA microarray was developed in conjunction with a rapid and high-throughput fluorescent meth...

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

Selection tool for foodborne norovirus outbreaks.

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Verhoef, Linda P B; Kroneman, Annelies; van Duynhoven, Yvonne; Boshuizen, Hendriek; van Pelt, Wilfrid; Koopmans, Marion

2009-01-01

Detection of pathogens in the food chain is limited mainly to bacteria, and the globalization of the food industry enables international viral foodborne outbreaks to occur. Outbreaks from 2002 through 2006 recorded in a European norovirus surveillance database were investigated for virologic and epidemiologic indicators of food relatedness. The resulting validated multivariate logistic regression model comparing foodborne (n = 224) and person-to-person (n = 654) outbreaks was used to create a practical web-based tool that can be limited to epidemiologic parameters for nongenotyping countries. Non-genogroup-II.4 outbreaks, higher numbers of cases, and outbreaks in restaurants or households characterized (sensitivity = 0.80, specificity = 0.86) foodborne outbreaks and reduced the percentage of outbreaks requiring source-tracing to 31%. The selection tool enabled prospectively focused follow-up. Use of this tool is likely to improve data quality and strain typing in current surveillance systems, which is necessary for identification of potential international foodborne outbreaks.

Efficacy of chemical treatments against murine norovirus, feline calicivirus, and MS2 bacteriophage.

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D'Souza, Doris H; Su, Xiaowei

2010-03-01

Human noroviruses pose an emerging public health threat, and despite stringent control strategies, variant strains continue to spread and cause disease outbreaks. Routinely used chemical sanitizers, such as sodium hypochlorite though effective on food contact surfaces, require high concentrations to cause reduction in enteric viral titers. The aim of this study was to evaluate the efficacy of trisodium phosphate (TSP) against three human enteric virus surrogates, murine norovirus (MNV-1), feline calicivirus (FCV), and bacteriophage MS2 in comparison to routinely used sanitizers. Three concentrations of TSP (1%, 2%, and 5%) at different contact times (30 sec and 1 min) were evaluated against the surrogate viruses individually inoculated on formica coupons. Our results showed that 5% TSP was effective in obtaining a >or=6 log(10) PFU reduction for MNV-1, FCV, and MS2 after a contact time of only 30 sec or 1 min similar to 10% household bleach (0.6% sodium hypochlorite, 5000 ppm available chlorine) for high titers of FCV and MS2, and with approximately 5 log(10) reduction after either 30 sec or 1 min on low viral titers. However, 2% TSP for 1 min resulted in >or=6 log(10) PFU reduction for FCV and MS2, but only a 1.05 log(10) PFU reduction for MNV-1 at high titers, with similar results after 30 sec. Decreasing TSP levels to 1% reduced FCV by approximately 2.65 log(10) PFU, MS2 by 4.5 log(10) PFU at high titers, and no reduction for MNV-1 after 30-sec or 1 min contact. Glutaraldehyde (2%) reduced FCV and MNV-1 titers by approximately 6 log(10) PFU; however, MS2 was reduced by only 3.22 and 3.74 log(10) PFU after 30 sec and 1 min, respectively, while 70% ethanol was not effective in reducing the three viruses at either high or low titers at both contact times. Alternative control strategies using TSP with short contact times should benefit the food industry in reducing norovirus transmission.

Probabilistic quantitative microbial risk assessment model of norovirus from wastewater irrigated vegetables in Ghana using genome copies and fecal indicator ratio conversion for estimating exposure dose.

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Owusu-Ansah, Emmanuel de-Graft Johnson; Sampson, Angelina; Amponsah, Samuel K; Abaidoo, Robert C; Dalsgaard, Anders; Hald, Tine

2017-12-01

The need to replace the commonly applied fecal indicator conversions ratio (an assumption of 1:10 -5 virus to fecal indicator organism) in Quantitative Microbial Risk Assessment (QMRA) with models based on quantitative data on the virus of interest has gained prominence due to the different physical and environmental factors that might influence the reliability of using indicator organisms in microbial risk assessment. The challenges facing analytical studies on virus enumeration (genome copies or particles) have contributed to the already existing lack of data in QMRA modelling. This study attempts to fit a QMRA model to genome copies of norovirus data. The model estimates the risk of norovirus infection from the intake of vegetables irrigated with wastewater from different sources. The results were compared to the results of a corresponding model using the fecal indicator conversion ratio to estimate the norovirus count. In all scenarios of using different water sources, the application of the fecal indicator conversion ratio underestimated the norovirus disease burden, measured by the Disability Adjusted Life Years (DALYs), when compared to results using the genome copies norovirus data. In some cases the difference was >2 orders of magnitude. All scenarios using genome copies met the 10 -4 DALY per person per year for consumption of vegetables irrigated with wastewater, although these results are considered to be highly conservative risk estimates. The fecal indicator conversion ratio model of stream-water and drain-water sources of wastewater achieved the 10 -6 DALY per person per year threshold, which tends to indicate an underestimation of health risk when compared to using genome copies for estimating the dose. Copyright © 2017 Elsevier B.V. All rights reserved.

Mecanismos involucrados en la promoción de crecimiento axonal por la glia envolvente del bulbo olfatorio

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Vilma C. Muñetón-Gómez

2001-06-01

Full Text Available La actividad que promueve el crecimiento de axones por la glia envolvente (GE del bulbo olfatorio depende de la expresión de diversas moléculas durante el desarrollo, la vida adulta y la reparación de lesiones nerviosas. Diversas moléculas tales como las neurotrofinas y sus receptores, los factores de crecimiento, las moléculas de adhesión celular, las moléculas de matriz extracelular y las moléculas asociadas con la mielinización son producidas por la glia del sistema olfatorio durante el desarrollo. Su expresión sostenida durante la vida adulta parece estar asociada con el reemplazo celular y la alta plasticidad de este sistema. A su vez, su expresión se involucra en procesos de reparación de lesiones mediados por trasplantes de glia. La migración de la GE, que acompaña axones en crecimiento, se observa durante el desarrollo y en procesos de regeneración luego de una lesión. Los trasplantes de,GE permiten la navegación de brotes regenerantes a través del tejido gliótico inhibidor formado luego de una lesión del sistema nervioso central. El propósito de esta revisión es profundizar en los mecanismos de actividad promotora de crecimiento axonal.

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

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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...

Detección de un brote de hepatitis A en Ceuta a través del sistema de información microbiológica Detection of a hepatitis A outbreak in Ceuta [Spain] through a microbiological surveillance system

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María Teresa Ortega-Maján

2008-08-01

Full Text Available Antecedentes: El Servicio de Vigilancia Epidemiológica de Ceuta comunicó al Centro Nacional de Epidemiología un aumento de casos de hepatitis A, detectado por el sistema de información microbiológica (SIM. Se investigó la posible existencia de un brote y se instauraron las medidas de control oportunas. Métodos: Se realizó un estudio descriptivo y otro de casos y controles. La información sociodemográfica, clínica y sobre factores de riesgo se obtuvo mediante un cuestionario cumplimentado por vía telefónica. Resultados: Se identificaron 19 casos. En el estudio univariante se encontró una asociación entre enfermar y el consumo de verduras crudas (odds ratio [OR] = 9,3; intervalo de confianza [IC] del 95%: 1,5-57,6 y de navajas (OR = 55; IC del 95%: 4,3-703,4. En el análisis multivariante sólo se mantuvo la asociación con el consumo de navajas (OR = 36,1; IC del 95%: 2,4-530,4. Ninguno de los 3 restaurantes inspeccionados disponía de control de facturas ni albaranes. Conclusiones: Se confirmó un brote de hepatitis A asociado al consumo de navajas en domicilios y restaurantes. El SIM fue la herramienta fundamental para su detección.Background: The Public Health Department of Ceuta informed the Spanish National Epidemiology Center of an increase in hepatitis A cases detected by the microbiological surveillance system. We conducted a study to confirm the outbreak and to initiate control measures. Methods: A descriptive study and a case-control study were performed. A standardized telephone questionnaire was used to collect information on demographic characteristics, symptoms, and risk factors. Results: Nineteen cases of hepatitis A were identified. Univariate analysis revealed an association between infection and eating raw vegetables (OR = 9.3; 95%CI: 1.5-57.6 or razor-shell (OR = 55; 95%CI: 4.3-703.4. In the logistic regression model, only razor-shell consumption remained a significant risk factor (OR = 36.1; 95%CI: 2

Brote de histoplasmosis en la Escuela de Cadetes de la Base Aérea de Morón, Provincia de Buenos Aires, República Argentina Histoplasmosis outbreak in Morón, Buenos Aires Province, Argentina

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R. Negroni

2010-12-01

Full Text Available Se describe un brote de histoplasmosis que afectó a 6 cadetes de la Fuerza Aérea Argentina, sin antecedentes patológicos previos. Todos consultaron por problemas respiratorios después de haber limpiado un hangar. En ese recinto se encontraron abundantes deyecciones de animales, presuntamente de palomas y murciélagos. Los pacientes sufrieron fiebre, mialgias, taquipnea y tos no productiva. Las radiografías y tomografías de tórax mostraron imágenes pulmonares micronodulares, engrosamiento de los tabiques interalveolares y adenopatías hiliares. Todos tuvieron una evolución favorable y no requirieron tratamiento antifúngico. Las pruebas de inmunodifusión y contrainmunoelectroforesis con antígenos de Histoplasma capsulatum fueron positivas, al igual que las intradermorreacciones con histoplasmina. Se recogieron 5 muestras de tierra del lugar, las que fueron inoculadas por vía intraperitoneal a 20 hámsteres. De los cultivos de hígado y bazo de dichos animales se consiguió aislar la fase micelial de H. capsulatum. La cepa aislada se comparó con las obtenidas de 12 pacientes argentinos utilizando perfiles genéticos y se observó un clado único con más de 96% de similitud, lo que confirma la homogeneidad de las cepas argentinas. Si bien la histoplasmosis es endémica en la Pampa húmeda, este es el primer brote totalmente documentado al sur del paralelo 34°.An histoplasmosis outbreak affecting 6 previously healthy Air Force cadets is herein presented. The patients suffered from fever and respiratory symptoms after having cleaned an abandoned hangar soiled with pigeons and bat droppings. They all presented fever, myalgia, tachypnea, and nonproductive cough. Chest X-ray and CT scan studies showed disseminated reticulonodular images affecting both lungs. Hiliar adenomegalies were also observed. All patients achieved a favourable outcome without antifungal treatment. Both serologic tests searching for specificic antibodies

[A norovirus-borne outbreak caused by contaminated bottled spring water in a school, Zhejiang province].

Science.gov (United States)

Shen, Ji-chuan; Lin, Jun-fen; Gao, Jie; Yao, Wen-ting; Wen, Dong; Liu, Guang-tao; Han, Jian-kang; Ma, Hui-lai; Zhang, Li-jie; Zhu, Bao-ping

2011-08-01

To study a local hospital reported acute gastroenteritis in a boarding school on its source of infection, mode of transmission and risk factors of the infection. A suspected case was defined as who had developed diarrhea (≥ 3 times/day) or vomiting among teachers or students of the school, during April 19 - 30, 2010. A confirmed case was from a probable case plus tested positive for norovirus in stool specimens by using RT-PCR. Stool specimens of cases and environmental specimens were collected for laboratory diagnosis. In a case-control study, we compared exposures to sources of bottled water, consumption of bottled water, and hygienic habits of 220 probable or confirmed cases from April 21 - 23 in the peak of the outbreak, together with another 220 controls, with frequency-matched by school grade. 20.3% of the 1536 students but none of the teachers developed the disease. 98.6% of the cases (n = 217) and 85.5% (n = 188) of the controls had drunk bottled water in the classroom (OR(M-H) = 12.3, 95%CI: 3.7 - 40.9). 47.9% (n = 104) of the cases and 41.5% (n = 78) of the controls had drunk unboiled bottled water in classroom (OR(M-H) = 3.8, 95%CI: 1.5 - 9.6). 47.9% (n = 104) of the cases and 48.4% (n = 91) of the controls had drunk bottled mixed water (boiled and unboiled) in the classroom (OR(M-H) = 2.8, 95%CI: 1.1 - 7.0). Stool specimens from 3 cases and one bottle of uncovered bottled water in classroom showed positive of having norovirus genotype II. Coliforms was cultured much higher rates than standard deviations in the bottled water. The factory making the bottled water was not licensed or having strict disinfection facilities. Bottled spring water contaminated by norovirus was responsible for this outbreak.

Factores de riesgo que influyen en el retardo del brote de la dentición temporal.: Policlínico "Turcios Lima", 2000-2003 Risk factors influencing the primary dentition eruption retardation. "Turcios Lima" polyclinics, 2000-2003

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Zoila Rosa Podadera Valdés

2004-04-01

Full Text Available Se realizó un estudio analítico de casos y controles en el área de salud del Policlínico "Turcios Lima" en el período comprendido entre julio de 2000 y julio de 2003, con el objetivo de identificar los factores de riesgo que influyen en el retardo del brote de la dentición temporal. El universo estuvo constituido por 1454 niños, de los cuales se obtuvo una muestra aleatoria de 93 niños. El análisis estadístico se realizó mediante porcentajes, la prueba Chi cuadrado y el cálculo de los odds ratio con sus intervalos de confianza. Se observó que el estado nutricional anormal al inicio del embarazo, las enfermedades asociadas con este, la inadecuada ganancia de peso de la madre y el desarrollo físico del niño, constituyeron los factores que más influyeron en la problemática estudiada. Se concluye que existe una significativa influencia del estado nutricional de la madre y del niño en el retardo del brote de su dentición temporal.An analytical case-control study was carried out in "Turcios Lima" polyclinics from July, 2000 to July, 2003, to identify the risk factors influencing primary dentition eruption retardation. The universe was formed by 1 454 children from whom a random sample of 93 children was taken. The statistical analysis was based on Chi-square test and calculation of percentages and odds ratios with confidence intervals. It was observed that poor nutritional status at the beginning of pregnancy, pregnancy-related diseases, inadequate weight gain by the mother and the physical development of the infant were the most influential factors. It was concluded that there is significant influence of the nutritional status of the child and the mother on primary dentition eruption retardation.

The fate of murine norovirus and hepatitis A virus during preparation of fresh produce by cutting and grating.

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Wang, Qing; Erickson, Marilyn; Ortega, Ynes R; Cannon, Jennifer L

2013-03-01

Human noroviruses and hepatitis A virus (HAV) are commonly associated with outbreaks occurring in restaurant establishments and catered events. Food handlers are major contributing factors to foodborne illnesses initiated in the kitchen setting. In this study, transfer of HAV and murine norovirus (MNV-1), a human norovirus surrogate, between produce (cucumbers, strawberries, tomatoes, cantaloupes, carrots, and honeydew melons) and common kitchen utensils (graters and knives) was investigated. The extent of virus transfer to produce during utensil application, in the presence and the absence of food residue, and the impact of knife surface properties (sharp, dull, serrated) was also investigated. Transfer of MNV-1 and HAV from produce items, initially contaminated with ~5.5 log PFU, to knives and graters during application ranged from 0.9 to 5.1 log PFU. MNV-1 transfer to knives was the greatest for cucumbers, strawberries, and tomatoes, and the least for honeydew melons, while transfer of HAV to knives was greater for tomatoes and honeydew melons than strawberries, cantaloupes, and cucumbers. After preparation of a contaminated produce item, knife cross-contamination easily occurred as viruses were detected on almost all of the seven produce items successively prepared. Produce residues on utensils often resulted in less virus transfer when compared to utensils without residue accumulation. Knife surface properties did not impact virus transfer. The ease of virus transfer between produce and utensils demonstrated by the current study highlights the importance of efforts aimed toward preventing cross-contamination in the kitchen environment.

Reprogramación celular de embriones de Anthurium andraeanum por fitohormonas para micropropagación masiva

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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.

Performance evaluation of Cepheid Xpert Norovirus kit with a user-modified protocol.

Science.gov (United States)

Wong, Rachel Shi-Lei; Yeo, Fion; Chia, Wai Theng; Lee, Chun Kiat; Leong, Mun Han; Ng, Christopher Wai-Siong; Poon, Kok Siong; Yan, Gabriel Zherong; Chiu, Lily-Lily; Yan, Benedict Junrong; Jureen, Roland; Koay, Evelyn Siew-Chuan; Lee, Hong Kai

2018-03-01

The Cepheid Xpert® Norovirus kit automates sample processing, nucleic acid extraction, and real-time reverse transcription polymerase chain reactions (RT-PCRs) to detect norovirus genogroups I (GI) and II (GII). Eighty-five stool samples collected between February 2015 and May 2017 were used to compare the performance of a user-modified Xpert assay against a clinically validated laboratory-developed test (LDT). Of the 85 samples, 54 were previously archived in -80°C freezer. The remaining 31 were fresh samples tested concurrently with the LDT. The results of all samples tested using the Xpert kit and LDT were found to be concordant, including 12 GI- and 42 GII-positive samples, 1 GI and GII coinfection, and 30 negative samples. Comparison of the assays showed perfect concordance with a kappa coefficient score of 1.00 (95%CI from 1.00 to 1.00). Of the 30 negative stool samples tested, three samples were positive for rotavirus detected using an immunochromatographic assay, with no cross-reactivity shown in both LDT and Xpert assays. In-run sample processing control of the Xpert assay for all negative samples tested showed no/minor inhibition. Compared to the LDT, the Xpert assay produced similar or better Ct values for detection. It also showed better mitigation of PCR inhibition in stool sample testing. © 2017 Wiley Periodicals, Inc.

Enfermedad por el virus del Chikungunya: historia y epidemiología

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Jorge Acosta-Reyes

2015-01-01

Full Text Available El 9 de diciembre de 2013 la Organización Panamericana de la Salud emitió una alerta epidemiológica debido a la detección de los primeros casos autóctonos de fiebre del Chikun-gunya en el continente americano; desde entonces este se ha convertido en un problema de salud pública. El primer reporte de un brote por el virus del Chikungunya se presentó en 1952-1953 en Tanzania. Las experiencias en epidemias en otros países han centrado la atención en que la presentación clínica no siempre tiene un comportamiento similar. Hasta 2005 todos los reportes mencionaban la presentación de la enfermedad como benigna y con cuadros clínicos bastantes similares, sin embargo, la aparición de epidemias después de ese año en las Islas Reunión y en la India describieron la presencia de cuadros graves, atípicos y un aumento de la mortalidad relacionados con la enfermedad. La región de las Américas debe prepararse para esta nueva epidemia. Esto hace necesario mejorar los conocimientos sobre la enfermedad; y un primer abordaje es a través de una descripción de la historia y epidemiología de la enfermedad por el virus del Chikungunya en el mundo.

Validation of ISO method 15216 part 1 - Quantification of hepatitis A virus and norovirus in food matrices.

NARCIS (Netherlands)

Lowther, J A; Bosch, A; Butot, S; Ollivier, J; Mäde, D; Rutjes, S A; Hardouin, G; Lombard, B; In't Veld, P; Leclercq, A

2017-01-01

Hepatitis A virus (HAV) and norovirus are important agents of food-borne human viral illness, with common vehicles including bivalve molluscan shellfish, soft fruit and various vegetables. Outbreaks of viral illness due to contamination of the surfaces of foods, or food preparation surfaces by for

Capturing the systemic immune signature of a norovirus infection: an n-of-1 case study within a clinical trial [version 3; referees: 2 approved

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Antony J. Cutler

2017-10-01

Full Text Available Background: The infection of a participant with norovirus during the adaptive study of interleukin-2 dose on regulatory T cells in type 1 diabetes (DILT1D allowed a detailed insight into the cellular and cytokine immune responses to this prevalent gastrointestinal pathogen. Methods: Serial blood, serum and peripheral blood mononuclear cell (PBMC samples were collected pre-, and post-development of the infection. To differentiate between the immune response to norovirus and to control for the administration of a single dose of aldesleukin (recombinant interleukin-2, rIL-2 alone, samples from five non-infected participants administered similar doses were analysed in parallel. Results: Norovirus infection was self-limited and resolved within 24 hours, with the subsequent development of anti-norovirus antibodies. Serum pro- and anti-inflammatory cytokine levels, including IL-10, peaked during the symptomatic period of infection, coincident with increased frequencies of monocytes and neutrophils. At the same time, the frequency of regulatory CD4+ T cell (Treg, effector T cell (Teff CD4+ and CD8+ subsets were dynamically reduced, rebounding to baseline levels or above at the next sampling point 24 hours later.  NK cells and NKT cells transiently increased CD69 expression and classical monocytes expressed increased levels of CD40, HLA-DR and SIGLEC-1, biomarkers of an interferon response. We also observed activation and mobilisation of Teffs, where increased frequencies of CD69+ and Ki-67+ effector memory Teffs were followed by the emergence of memory CD8+ Teff expressing the mucosal tissue homing markers CD103 and β7 integrin. Treg responses were coincident with the innate cell, Teff and cytokine response. Key Treg molecules FOXP3, CTLA-4, and CD25 were upregulated following infection, alongside an increase in frequency of Tregs with the capacity to home to tissues. Conclusions: The results illustrate the innate, adaptive and counter

Capturing the systemic immune signature of a norovirus infection: an n-of-1 case study within a clinical trial [version 2; referees: 2 approved

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Antony J. Cutler

2017-07-01

Full Text Available Background: The infection of a participant with norovirus during the adaptive study of interleukin-2 dose on regulatory T cells in type 1 diabetes (DILT1D allowed a detailed insight into the cellular and cytokine immune responses to this prevalent gastrointestinal pathogen. Methods: Serial blood, serum and peripheral blood mononuclear cell (PBMC samples were collected pre-, and post-development of the infection. To differentiate between the immune response to norovirus and to control for the administration of a single dose of aldesleukin (recombinant interleukin-2, rIL-2 alone, samples from five non-infected participants administered similar doses were analysed in parallel. Results: Norovirus infection was self-limited and resolved within 24 hours, with the subsequent development of anti-norovirus antibodies. Serum pro- and anti-inflammatory cytokine levels, including IL-10, peaked during the symptomatic period of infection, coincident with increased frequencies of monocytes and neutrophils. At the same time, the frequency of regulatory CD4+ T cell (Treg, effector T cell (Teff CD4+ and CD8+ subsets were dynamically reduced, rebounding to baseline levels or above at the next sampling point 24 hours later.  NK cells and NKT cells transiently increased CD69 expression and classical monocytes expressed increased levels of CD40, HLA-DR and SIGLEC-1, biomarkers of an interferon response. We also observed activation and mobilisation of Teffs, where increased frequencies of CD69+ and Ki-67+ effector memory Teffs were followed by the emergence of memory CD8+ Teff expressing the mucosal tissue homing markers CD103 and β7 integrin. Treg responses were coincident with the innate cell, Teff and cytokine response. Key Treg molecules FOXP3, CTLA-4, and CD25 were upregulated following infection, alongside an increase in frequency of Tregs with the capacity to home to tissues. Conclusions: The results illustrate the innate, adaptive and counter

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

Blueberry proanthocyanidins against human norovirus surrogates in model foods and under simulated gastric conditions.

Science.gov (United States)

Joshi, Snehal; Howell, Amy B; D'Souza, Doris H

2017-05-01

Blueberry proanthocyanidins (B-PAC) are known to decrease titers of human norovirus surrogates in vitro. The application of B-PAC as therapeutic or preventive options against foodborne viral illness needs to be determined using model foods and simulated gastric conditions in vitro. The objective of this study was to evaluate the antiviral effect of B-PAC in model foods (apple juice (AJ) and 2% reduced fat milk) and simulated gastrointestinal fluids against cultivable human norovirus surrogates (feline calicivirus; FCV-F9 and murine norovirus; MNV-1) over 24 h at 37 °C. Equal amounts of each virus (5 log PFU/ml) was mixed with B-PAC (1, 2 and 5 mg/ml) prepared either in AJ, or 2% milk, or simulated gastric fluids and incubated over 24 h at 37 °C. Controls included phosphate buffered saline, malic acid (pH 7.2), AJ, 2% milk or simulated gastric and intestinal fluids incubated with virus over 24 h at 37 °C. The tested viruses were reduced to undetectable levels within 15 min with B-PAC (1, 2 and 5 mg/ml) in AJ (pH 3.6). However, antiviral activity of B-PAC was reduced in milk. FCV-F9 was reduced by 0.4 and 1.09 log PFU/ml with 2 and 5 mg/ml B-PAC in milk, respectively and MNV-1 titers were reduced by 0.81 log PFU/ml with 5 mg/ml B-PAC in milk after 24 h. B-PAC at 5 mg/ml in simulated intestinal fluid reduced titers of the tested viruses to undetectable levels within 30 min. Overall, these results show the potential of B-PAC as preventive and therapeutic options for foodborne viral illnesses. Copyright © 2016. Published by Elsevier Ltd.

A Review of State Licensing Regulations to Determine Alignment with Best Practices to Prevent Human Norovirus Infections in Child-Care Centers.

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Leone, Cortney M; Jaykus, Lee-Ann; Cates, Sheryl M; Fraser, Angela M

2016-01-01

Close, frequent contact between children and care providers in child-care centers presents many opportunities to spread human noroviruses. We compared state licensing regulations for child-care centers with national guidelines written to prevent human noroviruses. We reviewed child-care licensing regulations for all 50 U.S. states and the District of Columbia in effect in June 2015 to determine if these regulations fully, partially, or did not address 14 prevention practices in four topic areas: (1) hand hygiene, (2) exclusion of ill people, (3) environmental sanitation, and (4) diapering. Approximately two-thirds (8.9) of the 14 practices across all state regulations were partially or fully addressed, with few (2.6) fully addressed. Practices related to exclusion of ill people and diapering were fully addressed most often, while practices related to hand hygiene and environmental sanitation were fully addressed least often. Regulations based on guidelines for best practices are one way to prevent the spread of human noroviruses in child-care facilities, if the regulations are enforced. Our findings show that, in mid-2015, many state child-care regulations did not fully address these guidelines, suggesting the need to review these regulations to be sure they are based on best practices.

Inactivation of murine norovirus by chemical biocides on stainless steel

Science.gov (United States)

2009-01-01

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. PMID:19583832

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.

Inactivation of human norovirus and Tulane virus in simple mediums and fresh whole strawberries by ionizing radiation

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Human norovirus (NoV) is a major cause of fresh produce associated outbreaks and human NoV in irrigation water can potentially lead to viral internalization in fresh produce. Therefore, there is a need to develop novel intervention strategies to target internalized viral pathogens while maintainin...

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

The effects of x-ray treatments on bioaccumulated murine norovirus-1 (MNV-1) and survivability, inherent microbiota, color, and firmness of Atlantic oysters (Crassostrea virginica) during storage at 5°C for 20 days

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In this study, we investigated the inactivation of human norovirus (HuNoV) surrogate Murine norovirus (MNV-1) by X-ray in whole-shell Atlantic oysters (Crassostrea virginica). We also investigated the effects of X-ray treatments on the survivability, inherent microbiota, color, and firmness of treat...

Wipes coated with a singlet-oxygen-producing photosensitizer are effective against human influenza virus but not against norovirus

NARCIS (Netherlands)

Verhaelen, Katharina; Bouwknegt, Martijn; Rutjes, Saskia; de Roda Husman, Ana Maria; Duizer, Erwin

2014-01-01

Transmission of enteric and respiratory viruses, including human norovirus (hNoV) and human influenza virus, may involve surfaces. In food preparation and health care settings, surfaces are cleaned with wipes; however, wiping may not efficiently reduce contamination or may even spread viruses,

An outbreak of norovirus gastroenteritis associated with asymptomatic food handlers in Kinmen, Taiwan

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Meng-Yu Chen

2016-05-01

Full Text Available Abstract Background In February 2015 an outbreak of gastroenteritis occurred in a distillery in Kinmen, Taiwan. At least 450 affected employees developed the symptoms of diarrhea and vomiting after attending a lunch banquet on 6 February. Epidemiological, laboratory and environmental investigations were conducted to identify the agent and source of this outbreak. Methods A case–control study was carried out among lunch attendees from the distillery. Using a semi-structured questionnaire, food and beverage consumption in the lunch banquet was assessed, as well as demographic and clinical data of the exposed people. An outbreak case was defined as a diner who developed at least three following symptoms: diarrhea, vomiting, abdominal pain, nausea, chills and/or weakness in the 72 h following the lunch. Controls were defined as lunch attendees who did not have any of the above symptoms. Rectal swabs or stool samples of the symptomatic exposed diners and food handlers as well as food and environmental samples were collected to test potential bacteria and viruses. Norovirus was detected by reverse transcription-polymerase chain reaction and sequence analysis. An environmental assessment, including environmental inspection of the restaurant and a review of work practices of food workers, was undertaken. Results Of 363 respondents with complete data, 169 met the case definition and 111 met the control definition. Consumption of pork liver in cold appetizers (adjusted odd ratio (aOR 3.23; 95 % confidence interval (CI: 1.26–8.30 and lamb chops (aOR: 3.98, 95 % CI: 1.74–9.11 were each associated with increased risk of illness. No cases but two asymptomatic food handlers who prepared or cooked the implicated foods tested positive for norovirus genotype I.6. Food and environmental samples were negative for any bacteria. Environmental assessment indicated that hand washing facilities were not properly accessible to food handlers. Inappropriate

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

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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

Ultraviolet-C efficacy against a norovirus surrogate and hepatitis A virus on a stainless steel surface.

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Park, Shin Young; Kim, An-Na; Lee, Ki-Hoon; Ha, Sang-Do

2015-10-15

In this study, the effects of 10-300 mWs/cm(2) of ultraviolet radiation (UV-C) at 260 nm were investigated for the inactivation of two foodborne viruses: murine norovirus-1 (MNV-1; a human norovirus [NoV] surrogate) and hepatitis A virus (HAV). We used an experimentally contaminated stainless steel surface, a common food-contact surface, to examine the effects of low doses of UV-C radiation on MNV-1 and HAV titers. The modified Gompertz equation was used to generate non-linear survival curves and calculate dR-values as the UV-C dose of 90% reduction for MNV-1 (R(2)=0.95, RMSE=0.038) and HAV (R(2)=0.97, RMSE=0.016). Total MNV-1 and HAV titers significantly decreased (pradiation than MNV-1. These data suggest that low doses of UV-C light on food contact surfaces could be effective to inactivate human NoV and HAV in restaurant, institutional, and industrial kitchens and facilities. Copyright © 2015 Elsevier B.V. All rights reserved.

Evolutionary changes in the capsid P2 region of Australian strains of the norovirus GII.Pe_GII.4.

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Bruggink, Leesa D; Moselen, Jean M; Roberts, Jason A; Marshall, John A

2017-07-01

The protruding (P) 2 region of the norovirus capsid is thought to include hypervariable sites involved in receptor binding. This study examines the changes that occurred in the P2 region of GII.Pe_GII.4 norovirus in the course of its evolution from a precursor phase (2008-2009), to an intermediate phase (2010) and finally to an epidemic phase (2012-2015). Twenty-two P2 region amino acid (aa) sequences (166 aa long) from all phases of the evolution of the virus were compared and the changes analysed.Results/key findings. Twenty sites in the P2 region underwent aa change and of these, 10 corresponded to previously proposed hypervariable sites and 10 to novel hypervariable sites. It was notable that aa changes at two sites, X and Y, only emerged as the epidemic phase progressed. 3D computer modelling of the P2 region indicated that neither X nor Y were in the uppermost 'crown', but further down in the 'neck' portion. The location of X and Y and the nature of aa change at Y suggest these sites were important in enhancing the structural integrity of the capsid, which in turn may have facilitated the longer term viability of the virus. The current study helps establish the validity of previously proposed hypervariable sites in the P2 region as well as indicating new ones. It also provides quantitative and qualitative data on how these sites changed over the evolutionary history of a particular norovirus strain.

Tres casos de odontomas

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Salvador Javier Santos Medina

2015-03-01

Full Text Available Los odontomas son los tumores odontogénicos más comunes, casi siempre se diagnostican accidentalmente, en exámenes radiográficos; pueden sospecharse al retardar el brote dentario o producir maloclusiones. Se clasifican en odontomas compuestos y complejos, ambos constituidos por estructuras dentales como: esmalte, dentina, cemento y tejido pulpar. Su eliminación quirúrgica y la biopsia es el tratamiento de elección. El propósito de este trabajo es reportar tres casos de pacientes atendidos en el Hospital Pediátrico de Las Tunas, todos remitidos previamente por el ortodoncista. El primero, tipo compuesto, en un escolar de 9 años de edad, masculino, asociado a un 31 retenido; el segundo caso se trata de un gran odontoma complejo en una escolar de 11 años de edad, femenina, que produjo interferencia en el brote del 11 y el tercero compuesto; en un escolar de 10 años, masculino, en la línea media entre 11 y 21, con producción de diastema y brote del 12 por palatino. De ellos uno fue descubierto por un examen radiográfico de rutina y los otros dos sospechados por la maloclusión secundaria; todos se trataron quirúrgicamente. Estos casos demuestran la frecuencia de estos tumores en la cavidad bucal y la importancia de la realización de exámenes clínicos y radiográficos para su detección y tratamiento precoz, así como la importancia de la interrelación entre el ortodoncista y el maxilofacial en la resolución satisfactoria de esta entidad

Brote de enfermedad alimentaria en la localidad de El Huecú, provincia de Neuquén Foodborne disease outbreak in El Huecú community, province of Neuquén

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C. López

2008-12-01

Full Text Available En febrero de 2006 ocurrió un brote epidémico de gastroenteritis aguda de origen alimentario, en ocasión de un festejo popular en una pequeña localidad de la provincia de Neuquén, Argentina. Aproximadamente 800 personas participaron de un almuerzo en las instalaciones del Gimnasio Municipal, y unas tres horas después de finalizado, cerca de 150 asistentes consultaron al hospital local, afectados por síndrome gastroentérico agudo. Se realizó una investigación epidemiológica caso-control a través de un muestreo representativo no probabilístico. Los resultados epidemiológicos establecieron un brote de ETA a fuente común, con una relación caso-control de 1:1,8. Los principales síntomas fueron cólicos abdominales (88%, vómitos (73,5% y diarrea (60%. La torta que se sirvió en ese evento fue identificada como el alimento causal (OR 9,79; IC 95%; 2,66-36,00; valor p = 0,0001, sujeto a condiciones higiénico-sanitarias insatisfactorias en los diferentes procesos de elaboración, conservación y manipulación. De una porción de la torta se aisló una cepa de Staphylococcus aureus subespecie aureus, coagulasa positiva, enterotoxigénica, con un recuento de 2,4x10(6 UFC/g, y también se aisló este microorganismo de tres muestras de manos y narinas de personas involucradas en la preparación y el servicio. Las cepas aisladas de un operador y de la torta portaron el gen sea y presentaron el mismo patrón de SmaI-PFGE. Se atribuyó el brote de ETA a la contaminación durante el proceso de preparación de la torta consumida durante ese almuerzo popular, lo que podría estar relacionado con deficiencias en aspectos higiénicos y con la falta de refrigeración y de mantenimiento de la cadena de frío.In the summer of 2006, an epidemic outbreak of acute gastrointestinal illness related to food consumption occurred in a small town in the province of Neuquén, Argentina. During a popular feast, approximately 800 local residents attended lunch

A universal primer-independent next-generation sequencing approach for investigations of norovirus outbreaks and novel variants

DEFF Research Database (Denmark)

Fonager, Jannik; Stegger, Marc; Rasmussen, Lasse Dam

2017-01-01

Norovirus (NoV) is the most common cause of non-bacterial gastroenteritis and is a major agent associated with outbreaks of gastroenteritis. Conventional molecular genotyping analysis of NoV, used for the identification of transmission routes, relies on standard typing methods (STM) by Sanger-seq...... to other important viruses in stool samples such as hepatitis A and enterovirus....

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

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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.

De flores, brotes y palmitos: alimentos olvidados

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Romano González Arce

2008-01-01

Full Text Available 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 2005. Las principales razones que explican el desuso de estos alimentos son: la introducción de hortalizas foráneas, que redujo el estatus de las nativas; la destrucción del hábitat propio de las diferentes especies; la modificación de las técnicas agrícolas que facilitaban su crecimiento; y la urbanización progresiva que redujo el espacio para los solares tradicionales. Estas plantas, por ser nativas, están totalmente adaptadas al clima y suelos del país, por lo que iniciar procesos de domesticación no resulta difícil. Se requiere mayor investigación en biología, etnobotánica, agronomía, química, y nutrición antes de promover su consumo masivo. Pero son fuente de nutrimentos para las poblaciones rurales del país.

Molecular characterization of norovirus variants and genetic diversity of noroviruses and sapoviruses in Thailand.

Science.gov (United States)

Chaimongkol, Natthawan; Khamrin, Pattara; Malasao, Rungnapa; Thongprachum, Aksara; Kongsricharoern, Tipachan; Ukarapol, Nuthapong; Ushijima, Hiroshi; Maneekarn, Niwat

2014-07-01

Norovirus (NoV) and Sapovirus (SaV) have been reported as a common cause of acute gastroenteritis worldwide. For a decade, surveillances of NoV and SaV have been conducted continually in Thailand. To monitor the epidemiological situation and to determine the genetic variation of NoV and SaV in Chiang Mai, Thailand, 567 samples collected from pediatric patients hospitalized with acute gastroenteritis were examined during 2007, and 2010-2011 by semi-nested RT-PCR and nucleotide sequencing methods. NoV was detected at 15.9%. Phylogenetic analysis revealed multiple NoV genotypes, GI/14 (1.1%), GII/1 (1.1%), GII/2 (1.1%), GII/3 (4.4%), GII/4 (65.6%), GII/6 (10.0%), GII/7 (2.2%), GII/12 (4.4%), GII/13 (3.3%), GII/16 (5.7%), and unclassified genotype (1.1%), circulating in this area. Among these, NoV GII/4 was the most prevalent genotype with a predominance of GII/4 2009 over other variants, 1996, 2006a, and 2006b. For SaV, the prevalence was 1.2% which was much lower than those of NoV and only SaV GI/1 was detected. This study highlights the epidemiology of NoV and SaV and genetic diversity of viruses circulating in pediatric patients hospitalized with acute gastroenteritis in Chiang Mai, Thailand. © 2013 Wiley Periodicals, Inc.

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

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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...

Outbreak of rubella after mass vaccination of children and adult women: challenges for rubella elimination strategies Brote epidémico de rubéola tras la vacunación masiva de niños y mujeres adultas: un reto para las estrategias de eliminación de la rubéola

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Ivone Andreatta Menegolla

2011-04-01

Full Text Available OBJECTIVE: To describe rubella outbreaks and control strategies in the Brazilian state of Rio Grande do Sul before rubella elimination. METHODS: We analyzed rubella and congenital rubella syndrome surveillance data for the state of Rio Grande do Sul and calculated age- and gender-specific incidence of confirmed rubella cases in 2007. We obtained data on measles-rubella doses administered during the outbreak from the state immunization program and reviewed the timing of suspect case notification and implementation of control measures. RESULTS: Of 2 842 confirmed rubella cases reported to the state health department in 2007, 2 145 (75.5% were in males (39.5 cases per 100 000 population and 697 (24.5% were in females (12.3 per 100 000 population. Incidence among 15- to 39-year-olds was 1.8 to 5.5 times higher in males than in females. Rubella genotype 2B was detected in nasopharyngeal specimens from 13 patients from multiple chains of transmission. Eight children were born with congenital rubella syndrome (5.9 cases per 100 000 births in 2008. Delayed notification of initial cases hampered early control efforts, resulting in outbreak spread throughout the state. Rubella transmission was interrupted after mass vaccination of adult men and women as part of a national vaccination campaign. CONCLUSIONS: Routine vaccination strategies and mass vaccination of adolescents and adults for accelerated rubella control and elimination should target men and women.OBJETIVO: Describir los brotes de rubéola y las estrategias para el control de la enfermedad anteriores a la eliminación de la rubéola en el estado brasileño de Rio Grande do Sul. MÉTODOS: Se analizaron los datos de vigilancia epidemiológica sobre la rubéola y el síndrome de rubéola congénita del estado de Rio Grande do Sul y se calculó la incidencia específica por edad y sexo de los casos confirmados de rubéola en el 2007. A partir del programa de vacunación estatal se obtuvieron datos

Development of rapid hemocyte-based extraction methods for detection of hepatitis A virus and murine norovirus in contaminated oysters

Science.gov (United States)

The human enteric pathogens, hepatitis A virus and human norovirus, have been shown to contaminate molluscan shellfish and cause foodborne disease in consumers. Rapid viral extraction methods are needed to replace current time consuming methods, which use whole oysters or dissected tissues. In our ...

In Situ CaptureRT-qPCR: A new simple and sensitive method to detect human norovirus in oysters

Science.gov (United States)

Human noroviruses (HuNoVs) are the major cause for the non-bacterial acute gastroenteritis worldwide. RT-qPCR is a widely used method to detect HuNoVs. However, the method is unable to discriminate between infectious and non-infectious viruses. Previously, we reported that the receptor mediated in s...

Norovírus em alimentos | Norovirus in foods

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Isabelle da Silva Luz

2017-08-01

Full Text Available Introdução: Os norovírus (NoV são importantes agentes causadores de gastroenterite de origem alimentar, com surtos associados ao consumo de frutas, vegetais folhosos, moluscos bivalves e alimentos de delicatessen. O aumento da importância epidemiológica destes vírus tem sido demonstrado pelo estabelecimento de redes laboratoriais de vigilância em diversos continentes. As infecções por NoV se tornaram mais conhecidas especialmente com a consolidação do mercado de navios de cruzeiros no país a partir de 2004. Objetivo: Este estudo tem como objetivo apresentar avanços relacionados à pesquisa de NoV em alimentos, destacando características deste patógeno e estratégias para sua detecção nestas matrizes. Método: Foi realizada uma revisão integrativa, pelo levantamento de artigos científicos com o objetivo de tratar dos principais aspectos de NoV. Resultados: Foi realizada uma ampla revisão da literatura, com a descrição dos principais resultados presentes na literatura consultada e a discussão de aspectos como doenças transmitidas por alimentos (DTA, vírus como contaminantes de alimentos, estabilidade e desinfecção, surtos de origem alimentar associados aos NoV, alimentos associados à contaminação por NoV, métodos de concentração e detecção de NoV em alimentos, estudos de avaliação de risco e prevenção e controle. Conclusões: Os registros de envolvimento de NoV em surtos de origem alimentar e a crescente diversidade genética destes vírus reforçam a necessidade de vigilância laboratorial e epidemiológica sobretudo nos países em desenvolvimento, como o Brasil. ============================================ Introduction: Noroviruses (NoV are important causative agents of foodborne gastroenteritis outbreaks associated with the consumption of fruits, leafy vegetables, bivalve molluscs and delicatessen foods. The establishment of laboratory surveillance networks in different continents has demonstrated

Human health implications of norovirus acute gastroenteritis as a result of hydric pollution

International Nuclear Information System (INIS)

Delgadillo Espinoza, Brenda; Moreira Segura, Cristian; Araya Rodriguez, Freddy

2011-01-01

An investigation, in Ciudad Quesada of Costa Rica, has been carried out to explore and characterize the outbreak of acute gastroenteritis in the area. Surveillance data and medical records of the patients were analyzed to develop a descriptive study between July 8 and July 14, 2010 in the canton of San Carlos. A fact sheet was applied to obtain information from patients. ELISA test was performed to the stool samples to detect the presence of enteropathogens. Water samples were analyzed for bacteria and fecal coliform in the distribution system. A total of 352 cases were confirmed in the studied region. The most frequent symptoms among confirmed cases were: diarrhea (94,2%), nausea (92,7%) and vomiting (91,7%). The average age of patients is 29 years (15,8%) and (50,8%) has been female. The age group that has been most affected are infants of 1-4 years (attack rate 18,2/1,000 population). The area that has been most affected is the central area of Ciudad Quesada. In five out of six stool tests has been possible to isolate the norovirus. In water Escherichia coli has been witnessed by what has been suggested that the norovirus has been transmitted by water contaminated with fecal matter. Water quality monitoring has been recommended and promote the use of potable water as well as the sensitization of rural communities about hygiene and disease prevention. (author) [es

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

. 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......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...

A non-foodborne norovirus outbreak among school children during a skiing holiday, Austria, 2007.

Science.gov (United States)

Kuo, Hung-Wei; Schmid, Daniela; Schwarz, Karin; Pichler, Anna-Margaretha; Klein, Heidelinde; König, Christoph; de Martin, Alfred; Allerberger, Franz

2009-01-01

Norovirus is increasingly recognized as a leading cause of outbreaks of foodborne disease. We report on an outbreak in Austria that reached a total of 176 cases, affecting pupils and teachers from four schools on a skiing holiday in a youth hostel in the province of Salzburg in December 2007. A questionnaire was sent to the four schools in order to obtain data from persons attending the school trip on disease status, clinical onset, duration of illness and hospitalization. A cohort study was undertaken to identify the sources of infection. The school trip attendees were interviewed by questionnaire or face-to-face on their exposure to food items from the menu provided by the hostel owner. Of the 284 school holiday-makers, 176 fitted the definition of an outbreak case (attack rate 61.9%). A total of 264 persons on the ski holiday participated in the cohort study (response rate 93%). The day-by-day food-specific analyses did not find any food items served on any of five days (December 8-12) of the holiday to be associated with infection risk. The day-specific risk analyses revealed Monday December 10 (RR: 9.04; 95% CI: 6.02-13.6; P Tourism is one of the primary industries in Austria. Timely involvement of the relevant public health authorities is essential in any outbreak of norovirus gastroenteritis, irrespective of its genesis.

Descripción de un brote de leptospirosis en la ciudad de Santa Fe, Argentina, marzo-abril de 1998 Description of a leptospirosis outbreak in the city of Santa Fe, Argentina, March-April 1998

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Norma B. Vanasco

2000-01-01

Full Text Available En marzo-abril de 1998 se identificó en un barrio de la ciudad de Santa Fe (Argentina un brote de una enfermedad aguda caracterizada por fiebre, cefaleas y mialgias intensas. Se presentan los estudios realizados en relación con este brote y los intentos de identificación de la fuente y del modo de transmisión. Los hallazgos epidemiológicos, serológicos y clínicos indicaron que el agente causal fue Leptospira interrogans. Como prueba de tamizaje se aplicó la técnica de aglutinación macroscópica con antígeno termorresistente, seguida de la prueba de ELISA y, como prueba de confirmación, la aglutinación microscópica frente a 10 serovariedades de L. interrogans. Se estudiaron 32 individuos, 8 perros y 8 muestras de agua. Se registraron 12 casos confirmados, 2 probables y 18 negativos. En seis perros se demostró la existencia de infección y en las muestras de agua se detectó la presencia de espiroquetas móviles. Los sueros humanos reaccionaron con las serovariedades ballum, canicola, icterohaemorrhagiae y pyrogenes, y los caninos con ballum, canicola y pomona. La coaglutinación observada en todos los casos confirmados indica que se trató de casos agudos de leptospirosis, pero no permite identificar la serovariedad causal. Salvo en el caso índice, no se reconoció clínicamente la enfermedad. Varios hechos sugieren que la causa del brote fue la inundación pluvial de la zona estudiada. Los resultados de este estudio resaltan la necesidad de una vigilancia activa de la leptospirosis ante desastres naturales como las inundaciones.In March-April 1998 in a neighborhood in the city of Santa Fe, Argentina, there was an outbreak of an acute disease characterized by fever, headaches, and intense myalgias. This article presents the studies surrounding this outbreak and the attempts to identify the source and the mode of transmission. The epidemiological, serological, and clinical findings indicated that the causative agent was Leptospira

[Food borne outbreak caused by the well water contaminated norovirus].

Science.gov (United States)

Tokutake, Yumi; Kobayashi, Masato; Akiyama, Miho; Aiki, Chikako; Nishio, Osamu

2006-05-01

In May 2004, 65 people from 18 groups of visitors to guesthouse (a traditional Japanese guesthouse) in the Nagano Prefecture, Japan developed acute gastroenteritis. Although these cases originally attributed to food poisoning, based on epidemiological and dietary surveys, there was nothing that is associated as a cause food. The same wall water was used throughout the guesthouse except in the kitchen, so testing was conducted on this water. Lordsdale variant strain of Norovirus was detected from both of the well water and the feces of patients and staff. The well supplying to the guesthouse was only 10 meters deep and fecal coliform group was also detected in the well water from the guesthouse. This suggested that the water source was contaminated by human feces.

Prevalence of group a rotavirus, enteric adenovirus, norovirus and astrovirus infections among children with acute gastroenteritis in al-qassim, saudi arabia

International Nuclear Information System (INIS)

Meqdam, M.M.

2007-01-01

To investigate the prevalence of Rotavirus, Adenovirus, Norovirus, and Astrovirus among Saudi children with gastroenteritis. This study was conducted at the Department of Medical Laboratories, Qassim University during the winter seasons of the years 2004 and 2005. A total of 284 diarrhoeal fecal specimens collected from children were tested for the gastroenteritis causing viruses using enzyme immunoassay. Of the 284 specimens, 142 (50%) were found to be positive for viruses causing gastroenteritis. Rotavirus (66.2%) was the most frequently detected, followed by adenovirus (15.5%), norovirus and astrovirus each with 9.2%. All of rotavirus detected belonged to group A. Eight specimens were found positive by two viruses. The introduction of simple and rapid tests for diagnosis of viruses causing gastroenteritis in our pediatric hospitals will improve patient care by reducing unnecessary treatments and hospital stay for patients. (author)

A large outbreak of acute gastroenteritis in Shippensburg, Pennsylvania, 1972 revisited: evidence for common source exposure to a recombinant GII.Pg/GII.3 norovirus.

Science.gov (United States)

Johnson, J A; Parra, G I; Levenson, E A; Green, K Y

2017-06-01

Historical outbreaks can be an important source of information in the understanding of norovirus evolution and epidemiology. Here, we revisit an outbreak of undiagnosed gastroenteritis that occurred in Shippensburg, Pennsylvania in 1972. Nearly 5000 people fell ill over the course of 10 days. Symptoms included diarrhea, vomiting, stomach cramps, and fever, lasting for a median of 24 h. Using current techniques, including next-generation sequencing of full-length viral genomic amplicons, we identified an unusual norovirus recombinant (GII.Pg/GII.3) in nine of 15 available stool samples from the outbreak. This particular recombinant virus has not been reported in recent decades, although GII.3 and GII.Pg genotypes have been detected individually in current epidemic strains. The consensus nucleotide sequences were nearly identical among the four viral genomes analysed, although each strain had three to seven positions in the genome with heterogenous non-synonymous nucleotide subpopulations. Two of these resulting amino acid polymorphisms were conserved in frequency among all four cases, consistent with common source exposure and successful transmission of a mixed viral population. Continued investigation of variant nucleotide populations and recombination events among ancestral norovirus strains such as the Shippensburg virus may provide unique insight into the origin of contemporary strains.

INS refuerza vigilancia y diagnóstico de enfermedad diarreica producida por Vibrio parahemolyticus

OpenAIRE

Huapaya, Blanca

2005-01-01

El Instituto Nacional de Salud (INS) está fortaleciendo la vigilancia y el diagnóstico en el Perú del Vibrio parahaemolyticus, bacteria causante de una enfermedad diarreica aguda, que a inicios de este año produjo un brote de aproximadamente 10 mil casos en Chile.

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

2011-01-01

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. PMID:21622782

The spatial diffusion of norovirus epidemics over three seasons in Tokyo.

Science.gov (United States)

Inaida, S; Shobugawa, Y; Matsuno, S; Saito, R; Suzuki, H

2015-02-01

We studied the spatial trend of norovirus (NoV) epidemics using sentinel gastroenteritis surveillance data for patients aged spreading pattern of NoV epidemics using sentinel surveillance data. Correlations of sentinel cases between the seasons and with demographic data were examined to identify the trend and related factors. A similar pattern of diffusion was observed over the seasons, and its mean correlation between seasons was significantly high. A higher number of cases were found in the peripheral area, which surrounds the most populated central area, and showed a correlation with the ratio of the children population (r = 0·321, P epidemic factor. Prevention with focus on the peripheral area is desirable.

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...

Emerging genotype (GGIIb) of norovirus in drinking water, Sweden.

Science.gov (United States)

Nygård, Karin; Torvén, Maria; Ancker, Camilla; Knauth, Siv Britt; Hedlund, Kjell-Olof; Giesecke, Johan; Andersson, Yvonne; Svensson, Lennart

2003-12-01

From May through June 2001, an outbreak of acute gastroenteritis that affected at least 200 persons occurred in a combined activity camp and conference center in Stockholm County. The source of illness was contaminated drinking water obtained from private wells. The outbreak appears to have started with sewage pipeline problems near the kitchen, which caused overflow of the sewage system and contaminated the environment. While no pathogenic bacteria were found in water or stools specimens, norovirus was detected in 8 of 11 stool specimens and 2 of 3 water samples by polymerase chain reaction. Nucleotide sequencing of amplicons from two patients and two water samples identified an emerging genotype designated GGIIb, which was circulating throughout several European countries during 2000 and 2001. This investigation documents the first waterborne outbreak of viral gastroenteritis in Sweden, where nucleotide sequencing showed a direct link between contaminated water and illness.

Conformational occlusion of blockade antibody epitopes, a novel mechanism of GII.4 human norovirus immune evasion

OpenAIRE

Lindesmith, Lisa C.; Mallory, Michael L.; Debbink, Kari; Donaldson, Eric F.; Brewer-Jensen, Paul D.; Swann, Excel W.; Sheahan, Timothy P.; Graham, Rachel L.; Beltramello, Martina; Corti, Davide; Lanzavecchia, Antonio; Baric, Ralph S.

2018-01-01

ABSTRACT Extensive antigenic diversity within the GII.4 genotype of human norovirus is a major driver of pandemic emergence and a significant obstacle to development of cross-protective immunity after natural infection and vaccination. However, human and mouse monoclonal antibody studies indicate that, although rare, antibodies to conserved GII.4 blockade epitopes are generated. The mechanisms by which these epitopes evade immune surveillance are uncertain. Here, we developed a new approach f...

Ecoepidemiología de la infección por rickettsias en roedores, ectoparásitos y humanos en el noroeste de Antioquia, Colombia

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Juan Carlos Quintero

2013-08-01

Full Text Available Introducción. Las rickettsias son bacterias patógenas usualmente transmitidas por ectoparásitos, como garrapatas, piojos o pulgas. En la última década se presentaron tres brotes de rickettsiosis con casos fatales en la región noroccidental de Antioquia y en un municipio limítrofe de Córdoba. Objetivo. Describir la ecología y la epidemiología de las infecciones por Rickettsia spp. en el Urabá antioqueño. Materiales y métodos. Se obtuvieron muestras de 354 roedores y se recolectaron 839 ectoparásitos de estos en los municipios de Apartadó, Turbo y Necoclí. Asimismo, se obtuvieron 220 sueros humanos. Estas muestras fueron estudiadas por reacción en cadena de la polimerasa (PCR e inmunofluorescencia indirecta (IFI para la detección de infección por rickettsias. Resultados. Por IFI se detectaron anticuerpos antirickettsias en 130 (43 % de los roedores y en 53 (24% de los sueros humanos estudiados. Además, se amplificaron secuencias del gen gltA específicas del género Rickettsia en 23 (6,8 % muestras de hígado de roedores, las cuales mostraron una similitud del 98,7 % con R. prowazekii. Una secuencia de gltA obtenida de larvas de garrapatas del género Amblyomma sp., tuvo una identidad mayor de 99 % con las secuencias de R. tamurae. Conclusión. Estos resultados demuestran la circulación de rickettsias en roedores, ectoparásitos y humanos en los municipios estudiados.   doi: http://dx.doi.org/10.7705/biomedica.v33i0.735

Identificación y caracterización genética de agentes virales diarreagénicos en niños menores de cinco años de edad con o sin diarrea en Bucaramanga

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Nayibe Tatiana Sánchez Álvarez

2016-06-01

Full Text Available Introducción: La enfermedad diarreica aguda (EDA, es una de las principales causas de morbi-mortalidad en todos los grupos de edad, con mayor incidencia en niños menores de cinco años. EDA es causada por diversos agentes. Entre los que se asocian de tipo bacteriano, parasitario y principalmente viral. La epidemiología y el diagnóstico en las infecciones virales es limitado debido a los altos costos en las técnicas moleculares y al desconocimiento por parte del personal de salud sobre su importancia. En Colombia son escasos los estudios reportados sobre la prevalencia de las infecciones virales diarreagénicas. Objetivo: Identificar la frecuencia de agentes virales asociados a las enfermedades diarreicas y caracterizar el agente viral más en los niveles genéticos y filogenéticos. Materiales y métodos: Este estudio hace parte de un estudio de casos y controles aprobado por el National Institutes of Health (NIH, en esta investigación se incluyeron 405 niños con EDA y 405 controles de niños sanos. Las muestras de heces se procesaron por métodos moleculares basados en la detección de adenovirus, norovirus, sapovirus, y astrovirus. Rotavirus se detectó mediante un ensayo de ELISA convencional. Análisis filogenético se llevó a cabo tanto para rotavirus como norovirus, mediante la amplificación de secuencia de ADN de los fragmentos de la región C de la cápside y detección de las proteínas VP4 y VP7 respectivamente. Las secuencias para cada tipo de virus se compararon y se construyó un árbol filogenético utilizando secuencias de referencia. Resultados: En general 243 virus fueron detectados entre las 810 muestras, 183 en casos y 60 en controles. El virus con mayor prevalencia fue norovirus GII con 10.9 %, seguido de rotavirus sapovirus con 5.1 %. Norovirus GI, astrovirus y adenovirus fueron identificados en 3.8 %, 3.2 % y 1.7 % respectivamente. La positividad fue más frecuente en el rango de edad  de 12 a 23 meses y de 24 a

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.

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

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 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.

Determinación de la composición fenólica y actividad antioxidante en brotes de clones de Pinus pinaster procedentes de tres orígenes contrastantes

OpenAIRE

Baizán González, Silvia

2013-01-01

Pinus pinaster es una especie de gran importancia económica y ecológica y que presenta una gran diversidad genética. En nuestro grupo de trabajo disponemos de una colección clonal representativa de toda el área de distribución natural de la especie. En una parcela que alberga un ensayo anidado de 10 procedencias x 5 familias x 5 clones x 8 copias y con distribución de bloques aleatorizados, se evaluó la variabilidad del color en base al Espacio de Color CIELAB de los brotes que emergen en pri...

Potencial de regeneración de Psychotria ipecacuanha (Rubiaceae a partir de capas delgadas de células

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Catalina Botero Giraldo

2015-09-01

Full Text Available Conociendo las propiedades medicinales de la especie vegetal Psychotria ipecacuanha (Brot. Stokes, su crítico estado de conservación, así como las dificultades que presenta para la propagación efectiva, el presente estudio tuvo como objetivo evaluar su potencial de propagación por los sistemas de regeneración in vitro, organogénesis y embriogénesis somática. Para este propósito, capas delgadas de células (CDCs de tallos y de hojas, así como segmentos foliares fueron sometidos a diferentes tratamientos con reguladores de crecimiento y condiciones de luz. Además se estableció el efecto de diferentes longitudes de onda vía diodos emisores de luz (LEDs, sobre la regeneración en estos explantes y nudos provenientes de plantas in vitro. Los resultados obtenidos mostraron que los segmentos de hoja y las CDCs de tallo sembrados en el medio de cultivo MS suplementado con las combinaciones de los reguladores de crecimiento IBA + BAP e IBA + TDZ formaron embriones somáticos y brotes. Los cortes histológicos realizados corroboraron estos dos tipos de origen. Se encontró que bajo la condición lumínica 16/8, se alcanzaron los mejores resultados de inducción de brotes y embriones. En cuanto al efecto de las diferentes longitudes de onda de luz, se encontró que las correspondientes al rojo, verde y blanca, favorecieron el crecimiento y desarrollo de brotes y la inducción de embriones somáticos. El desarrollo de los brotes a partir de los nudos no presentó diferencias estadísticas entre los tratamientos con LEDs, por lo que se recomienda el uso de la luz blanca continua y con fotoperiodo durante el proceso de multiplicación y desarrollo de estos.

Attempts to grow human noroviruses, a sapovirus, and a bovine norovirus in vitro.

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Tomoichiro Oka

Full Text Available Noroviruses (NoVs and Sapoviruses (SaVs are enteric caliciviruses that have been detected in multiple mammalian species, including humans. Currently, efficient cell culture systems have been established only for murine NoVs and porcine SaV Cowden strain. Establishment of an efficient in vitro cell culture system for other NoVs and SaVs remains challenging; however, human NoV (HuNoV replication in 3D cultured Caco-2 cells and a clone of Caco-2 cells, C2BBe1, human enteroids and in human B cells has been reported. In this study, we tested various cells and culture conditions to grow HuNoVs and a human SaV (HuSaV to test the possibility of the propagation in different cells and culture conditions. We also attempted to grow a bovine NoV (BoNoV in ex vivo organ cultures. We did not observe significant RNA level increases for HuSaV and BoNoV under our test conditions. HuNoV RNA levels increased to a maximum of ~600-fold in long-term Caco-2 cells that were cultured for 1-2 months in multi-well plates and inoculated with HuNoV-positive and bacteria-free human stool suspensions using serum-free medium supplemented with the bile acid, GCDCA. However, this positive result was inconsistent. Our results demonstrated that HuNoVs, BoNoV and HuSaV largely failed to grow in vitro under our test conditions. Our purpose is to share our findings with other researchers with the goal to develop efficient, reproducible simplified and cost-effective culture systems for human and animal NoVs and SaVs in the future.

Critical review of norovirus surrogates in food safety research: rationale for considering volunteer studies.

Science.gov (United States)

Richards, Gary P

2012-03-01

The inability to propagate human norovirus (NoV) or to clearly differentiate infectious from noninfectious virus particles has led to the use of surrogate viruses, like feline calicivirus (FCV) and murine norovirus-1 (MNV), which are propagatable in cell culture. The use of surrogates is predicated on the assumption that they generally mimic the viruses they represent; however, studies are proving this concept invalid. In direct comparisons between FCV and MNV, their susceptibility to temperatures, environmental and food processing conditions, and disinfectants are dramatically different. Differences have also been noted between the inactivation of NoV and its surrogates, thus questioning the validity of surrogates. Considerable research funding is provided globally each year to conduct surrogate studies on NoVs; however, there is little demonstrated benefit derived from these studies in regard to the development of virus inactivation techniques or food processing strategies. Human challenge studies are needed to determine which processing techniques are effective in reducing NoVs in foods. A major obstacle to clinical trials on NoVs is the perception that such trials are too costly and risky, but in reality, there is far more cost and risk in allowing millions of unsuspecting consumers to contract NoV illness each year, when practical interventions are only a few volunteer studies away. A number of clinical trials have been conducted, providing important insights into NoV inactivation. A shift in research priorities from surrogate research to volunteer studies is essential if we are to identify realistic, practical, and scientifically valid processing approaches to improve food safety.

Prevalence of Human Parainfluenza Viruses and Noroviruses Genomes on Office Fomites.

Science.gov (United States)

Stobnicka, Agata; Gołofit-Szymczak, Małgorzata; Wójcik-Fatla, Angelina; Zając, Violetta; Korczyńska-Smolec, Joanna; Górny, Rafał L

2018-06-01

The aim of this study was to evaluate the potential role of office fomites in respiratory (human parainfluenza virus 1-HPIV1, human parainfluenza virus 3-HPIV3) and enteric (norovirus GI-NoV GI, norovirus GII-NoV GII) viruses transmission by assessing the occurrence of these viruses on surfaces in office buildings. Between 2016 and 2017, a total of 130 surfaces from open-space and non-open-space rooms in office buildings located in one city were evaluated for HPIV1, HPIV3, NoV GI, and NoV GII viral RNA presence. Detection of viruses was performed by RT-qPCR method. Study revealed 27 positive samples, among them 59.3% were HPIV3-positive, 25.9% HPIV1-positive, and 14.8% NoV GII-positive. All tested surfaces were NoV GI-negative. Statistical analysis of obtained data showed that the surfaces of office equipment including computer keyboards and mice, telephones, and desktops were significantly more contaminated with respiratory viruses than the surfaces of building equipment elements such as door handles, light switches, or ventilation tracts (χ 2 p = 0.006; Fisher's Exact p = 0.004). All examined surfaces were significantly more contaminated with HPIVs than NoVs (χ 2 p = 0.002; Fisher's Exact p = 0.003). Office fomites in open-space rooms were more often contaminated with HPIVs than with NoVs (χ 2 p = 0.016; Fisher's Exact p = 0.013). The highest average concentration of HPIVs RNA copies was observed on telephones (1.66 × 10 2 copies/100 cm 2 ), while NoVs on the light switches (1.40 × 10 2 copies/100 cm 2 ). However, the Kruskal-Wallis test did not show statistically significant differences in concentration levels of viral RNA copies on surfaces between the all tested samples. This study unequivocally showed that individuals in office environment may have contact with both respiratory and enteric viral particles present on frequently touched surfaces.

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. Published by Elsevier Ltd.

Pyrosequencing Analysis of Norovirus Genogroup II Distribution in Sewage and Oysters: First Detection of GII.17 Kawasaki 2014 in Oysters.

Science.gov (United States)

Pu, Jian; Kazama, Shinobu; Miura, Takayuki; Azraini, Nabila Dhyan; Konta, Yoshimitsu; Ito, Hiroaki; Ueki, You; Cahyaningrum, Ermaya Eka; Omura, Tatsuo; Watanabe, Toru

2016-12-01

Norovirus GII.3, GII.4, and GII.17 were detected using pyrosequencing in sewage and oysters in January and February 2015, in Japan. The strains in sewage and oyster samples were genetically identical or similar, predominant strains belonging to GII.17 Kawasaki 2014 lineage. This is the first report of GII.17 Kawasaki 2014 in oysters.

Evaluation of Chlorine Treatment Levels for Inactivation of Human Norovirus and MS2 Bacteriophage during Sewage Treatment.

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Kingsley, David H; Fay, Johnna P; Calci, Kevin; Pouillot, Régis; Woods, Jacquelina; Chen, Haiqiang; Niemira, Brendan A; Van Doren, Jane M

2017-12-01

This study examined the inactivation of human norovirus (HuNoV) GI.1 and GII.4 by chlorine under conditions mimicking sewage treatment. Using a porcine gastric mucin-magnetic bead (PGM-MB) assay, no statistically significant loss in HuNoV binding (inactivation) was observed for secondary effluent treatments of ≤25 ppm total chlorine; for both strains, 50 and 100 ppm treatments resulted in ≤0.8-log 10 unit and ≥3.9-log 10 unit reductions, respectively. Treatments of 10, 25, 50, and 100 ppm chlorine inactivated 0.31, 1.35, >5, and >5 log 10 units, respectively, of the norovirus indicator MS2 bacteriophage. Evaluation of treatment time indicated that the vast majority of MS2 and HuNoV inactivation occurred in the first 5 min for 0.2-μm-filtered, prechlorinated secondary effluent. Free chlorine measurements of secondary effluent seeded with MS2 and HuNoV demonstrated substantial oxidative burdens. With 25, 50, and 100 ppm treatments, free chlorine levels after 5 min of exposure ranged from 0.21 to 0.58 ppm, from 0.28 to 16.7 ppm, and from 11.6 to 53 ppm, respectively. At chlorine treatment levels of >50 ppm, statistically significant differences were observed between reductions for PGM-MB-bound HuNoV (potentially infectious) particles and those for unbound (noninfectious) HuNoV particles or total norovirus particles. While results suggested that MS2 and HuNoV (measured as PGM-MB binding) behave similarly, although not identically, both have limited susceptibility to chlorine treatments of ≤25 ppm total chlorine. Since sewage treatment is performed at ≤25 ppm total chlorine, targeting free chlorine levels of 0.5 to 1.0 ppm, these results suggest that traditional chlorine-based sewage treatment does not inactivate HuNoV efficiently. IMPORTANCE HuNoV is ubiquitous in sewage. A receptor binding assay was used to assess inactivation of HuNoV by chlorine-based sewage treatment, given that the virus cannot be routinely propagated in vitro Results reported here

Caracterización genética del virus de la fiebre amarilla proveniente de un brote icterohemorrágico en una comunidad nativa del distrito de Imaza, Amazonas, 2005

OpenAIRE

Yábar, Carlos; Mamani, Enrique

2006-01-01

La fiebre amarilla (FA) sigue siendo una enfermedad de importancia en salud pública en el mundo a pesar de la existencia de una vacuna eficaz (WHO, 2005). En Sudamérica, el Perú fue uno de los países que registró el mayor número de casos de FA durante el 2004 (WHO, 2005), contando con zonas endémicas que se extienden desde la selva norte hacia la selva central. Recientemente, en diciembre de 2005 la Dirección de Salud (DISA) de Bagua tomó conocimiento de un brote icterohemorrágico en la co...

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

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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.

Norovirus Transmission between Hands, Gloves, Utensils, and Fresh Produce during Simulated Food Handling

Science.gov (United States)

Aho, E.; Mikkelä, A.; Ranta, J.; Tuominen, P.; Rättö, M.; Maunula, L.

2014-01-01

Human noroviruses (HuNoVs), a leading cause of food-borne gastroenteritis worldwide, are easily transferred via ready-to-eat (RTE) foods, often prepared by infected food handlers. In this study, the transmission of HuNoV and murine norovirus (MuNoV) from virus-contaminated hands to latex gloves during gloving, as well as from virus-contaminated donor surfaces to recipient surfaces after simulated preparation of cucumber sandwiches, was inspected. Virus transfer was investigated by swabbing with polyester swabs, followed by nucleic acid extraction from the swabs with a commercial kit and quantitative reverse transcription-PCR. During gloving, transfer of MuNoV dried on the hand was observed 10/12 times. HuNoV, dried on latex gloves, was disseminated to clean pairs of gloves 10/12 times, whereas HuNoV without drying was disseminated 11/12 times. In the sandwich-preparing simulation, both viruses were transferred repeatedly to the first recipient surface (left hand, cucumber, and knife) during the preparation. Both MuNoV and HuNoV were transferred more efficiently from latex gloves to cucumbers (1.2% ± 0.6% and 1.5% ± 1.9%) than vice versa (0.7% ± 0.5% and 0.5% ± 0.4%). We estimated that transfer of at least one infective HuNoV from contaminated hands to the sandwich prepared was likely to occur if the hands of the food handler contained 3 log10 or more HuNoVs before gloving. Virus-contaminated gloves were estimated to transfer HuNoV to the food servings more efficiently than a single contaminated cucumber during handling. Our results indicate that virus-free food ingredients and good hand hygiene are needed to prevent HuNoV contamination of RTE foods. PMID:24951789

PROPAGACIÓN IN VITRO DE Acacia mangium Willd

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LUZ ANGELA TORRES

Full Text Available Acacia Acacia mangium Willd es una de las especies forestales más plantadas por la calidad de su madera y rápido crecimiento; sin embargo, los estudios de propagación clonal son pocos. El presente trabajo tuvo como objetivo desarrollar un protocolo de micropropagacion a partir de explantes con meristemos preexistentes. Los explantes consistieron de brotes de plantas de tres meses de edad mantenidas en invernadero. La desinfección se realizó con diferentes concentraciones de hipoclorito de sodio y antibióticos, y fueron establecidos en medio MS con diferentes concentraciones (0; 0,44; 0,88 y 2,22 µM de BAP. Los brotes micropropagados fueron enraizados con diferentes dosis de ANA y AIB, finalmente los brotes, con o sin raíces, fueron transferidos a condiciones ex vitro para evaluar el porcentaje de supervivencia. Los datos mostraron que 1,0% NaOCl y cefalexina (2 mg L-1 permitieron obtener el mayor porcentaje de explantes libres de contaminación (67%. El mayor número promedio de brotes ocurrió con 2,22 µM de BAP y el mayor número promedio de raíces se observo al utilizar 2,69 µM de ANA. La adaptación de las plantas en condiciones ex vitro fue exitoso lográndose obtener un 87% de supervivencia

PROPAGACIÓN IN VITRO DE BAMBÚ CHINO (Dracaena sanderiana L.

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Marcos Daquinta

2010-06-01

Full Text Available Con el objetivo de establecer un protocolo para la propagación in vitro de Bambú chino (Dracaena sanderiana L., se evaluaron diferentes tiempos de desinfección de las yemas con bicloruro de mercurio (HgCl2 a 0.2% (m/v, distintas condiciones de cultivo para el establecimiento de las yemas, tanto en condiciones de luz y oscuridad, así como diferentes formas de cultivo y manejo de los explantes para la proliferación de los brotes y distintos niveles de AIB para el enraizamiento de los brotes. Se logró realizar el establecimiento in vitro de la Dracaena sanderiana a partir de yemas laterales de estacas de plantas adultas, en medio de cultivo MS (1962 con 1 mg L-1 de BAP en estado semisólido y bajo condiciones de oscuridad. Para la proliferación de brotes, el seccionamiento longitudinal de estos y los sistemas de inmersión permanente, en el medio de cultivo MS (1962 enriquecido con BAP (2 mg L-1 combinado con ANA resulto ser el mejor tratamiento. La aclimatización de los brotes de Dracaena sanderiana se realizó en un sustrato compuesto de zeolita cachaza (1:1 en condiciones de casa de cultivo, con un sistema de riego por microjet.

Estudio de un brote poblacional de hepatitis A: Efectividad de la vacunación como medida de control Study of a population outbreak of hepatitis A: Effectiveness of vaccination as a control measure

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María José Díaz Villaescusa

2010-08-01

Full Text Available Objetivo: Describir un brote de hepatitis A en la ciudad de Albacete y valorar la efectividad de las medidas de control adoptadas. Métodos: Constatada la existencia del brote, se establecieron las definiciones de caso. Se recogieron los datos clínicos y epidemiológicos de los casos mediante encuesta. Se describió la distribución temporoespacial, mediante la localización de los casos y la curva epidémica. Se pusieron en marcha, como medidas de control y prevención inmediatas, la administración de inmunoglobulina (IG y educación sanitaria a la población en riesgo. Resultados: Desde enero de 2005 a enero de 2006 se declararon 62 casos. Los grupos de edad más afectados fueron los escolares y los adultos jóvenes. El mecanismo de transmisión fue de persona a persona. La curva epidémica presenta dos periodos. Las medidas de control iniciales fueron higiénicas y administración de IG a los contactos; en el segundo periodo se complementaron con la vacunación contra la hepatitis A, administrada a los alumnos de los centros de enseñanza de los dos barrios inicialmente implicados. La extensión del brote a los barrios colindantes y la alarma social que ocasionó hicieron que se ampliara la vacunación a los centros de enseñanza próximos a aquellos en que se habían detectado casos. Después de la última vacunación, en enero de 2006, no se notificó ningún caso. Conclusiones: El uso de la vacuna postexposición frente al virus de la hepatitis A en la población escolar y los adultos jóvenes parece ser una medida efectiva para el control de un brote.Objective: To describe an outbreak of hepatitis A in the city of Albacete (Spain and to assess the effectiveness of the control measures implemented. Methods: When the outbreak was noted, definitions of a case were established. Clinical and epidemiological data were collected through a survey. The temporal-spatial distribution was identified through mapping and the epidemic curve. Health

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

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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.

An outbreak of foodborne norovirus gastroenteritis linked to a restaurant in Melbourne, Australia, 2014

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Shaun P. Coutts

2017-05-01

Full Text Available Introduction: In May 2014 an outbreak of norovirus occurred among patrons of a restaurant in Melbourne, Australia. Investigations were conducted to identify the infectious agent, mode of transmission and source of illness, and to implement controls to prevent further transmission. Methods: A retrospective case-control study was conducted to test the hypothesis that food served at the restaurant between 9 and 15 May 2014 was the vehicle for infection. A structured questionnaire was used to collect demographic, illness and food exposure data from study participants. To ascertain whether any food handlers had experienced gastroenteritis symptoms and were a possible source of infection, investigators contacted and interviewed staff who had worked at the restaurant between 9 and 16 May 2014. Results: Forty-six cases (including 16 laboratory-confirmed cases of norovirus and 49 controls were interviewed and enrolled in the study. Results of the analysis revealed a statistically significant association with illness and consumption of grain salad (OR: 21.6, 95% CI: 1.8–252.7, p = 0.015 and beetroot dip (OR: 22.4, 95% CI: 1.9–267.0, p = 0.014. An interviewed staff member who reported an onset of acute gastrointestinal illness on 12 May 2014 had prepared salads on the day of onset and the previous two days. Discussion: The outbreak was likely caused by person-to-food-to-person transmission. The outbreak emphasizes the importance of the exclusion of symptomatic food handlers and strict hand hygiene practices in the food service industry to prevent contamination of ready-to-eat foods and the kitchen environment.

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

Virucidal efficacy of treatment with photodynamically activated curcumin on murine norovirus bio-accumulated in oysters.

Science.gov (United States)

Wu, Juan; Hou, Wei; Cao, Binbin; Zuo, Tao; Xue, Changhu; Leung, Albert Wingnang; Xu, Chuanshan; Tang, Qing-Juan

2015-09-01

Norovirus (NoV) is one of the most important seafood- and water-borne viruses, and is a major cause of acute gastroenteritis outbreaks. In the present study we investigated the effect of curcumin as a sensitizer to photodynamic treatment both in buffer and in oysters against murine norovirus 1 (MNV-1), a surrogate of NoV. MNV-1 cultured in buffer and MNV-1 bio-accumulated in oysters were irradiated with a novel LED light source with a wavelength of 470nm and an energy of 3.6J/cm(2). Inactivation of MNV-1 was investigated by plaque assays. After virus was extracted from the gut of oysters treated over a range of curcumin concentrations, the ultrastructural morphology of the virus was observed using electron microscopy, and the integrity of viral nucleic acids and stability of viral capsid proteins were also determined. Results showed that the infectivity of MNV-1 was significantly inhibited by 1-3logPFU/ml, with significant damage to viral nucleic acids in a curcumin dose-dependent manner after photodynamic activation. Virus morphology was altered after the photodynamic treatment with curcumin, presumably due to the change of the viral capsid protein structures. The data suggest that treatment of oysters with photodynamic activation of curcumin is a potentially efficacious and cost-effective method to inactivate food-borne NoV. Further studies are necessary to evaluate the toxicology of this approach in detail and perform sensory evaluation of the treated product. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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...

Probabilistic quantitative microbial risk assessment model of norovirus from wastewater irrigated vegetables in Ghana using genome copies and fecal indicator ratio conversion for estimating exposure dose

DEFF Research Database (Denmark)

Owusu-Ansah, Emmanuel de-Graft Johnson; Sampson, Angelina; Amponsah, Samuel K.

2017-01-01

physical and environmental factors that might influence the reliability of using indicator organisms in microbial risk assessment. The challenges facing analytical studies on virus enumeration (genome copies or particles) have contributed to the already existing lack of data in QMRA modelling. This study......The need to replace the commonly applied fecal indicator conversions ratio (an assumption of 1:10− 5 virus to fecal indicator organism) in Quantitative Microbial Risk Assessment (QMRA) with models based on quantitative data on the virus of interest has gained prominence due to the different...... attempts to fit a QMRA model to genome copies of norovirus data. The model estimates the risk of norovirus infection from the intake of vegetables irrigated with wastewater from different sources. The results were compared to the results of a corresponding model using the fecal indicator conversion ratio...

Sarampión en Chile 1960-1985

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S. Barja Y.

2017-05-01

Full Text Available El efecto inmediato más destacado del programa de vacunación es la notable caída de la tasa de morbilidad y la virtual eliminación de las muertes causadas por sarampión. Persiste, sin embargo, un remanente de casos y continúan ocurriendo brotes esporádicos de magnitud variable. Ha habido, además, como efecto tardío no esperado, un desplazamiento paulatino de las denuncias hacia edades mayores que vaticinan su importancia relativa creciente en el adulto. Los hechos señalados serían consecuencia de la persistencia de "susceptibles residuales" cuyos incrementos periódicos dan origen a brotes cada vez que alcanzan un cifra crítica.

The influence of temperature pH and water immersion on the high hydrostatic pressure inactivation of GI.1 and GII.4 human noroviruses

Science.gov (United States)

Detection of human norovirus (HuNoV) usually relies on molecular biology techniques, such as qRT PCR. Since histo-blood group antigens (HBGAs) are the functional receptors for HuNoV, HuNoV can bind to porcine gastric mucin (PGM), which contains HBGA-like antigens. In this study, PGM conjugated magn...

Descripción de un brote epidémico de toxoplasmosis aguda en pacientes inmunocompetentes miembros de las fuerzas militares de Colombia durante operaciones de selva Description of an epidemic outbreak of acute toxoplasmosis in immunocompetent patients from Colombian Armed Forces during jungle operations

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Luis Eduardo Pino

2009-06-01

Full Text Available La toxoplasmosis es una de las infecciones oportunistas más frecuentes en los pacientes infectados con el virus de inmunodeficiencia humana (VIH, mientras que, en los pacientes inmunocompetentes, la infección es sintomática sólo en 10% a 20% de los casos, generalmente con un comportamiento benigno y autolimitado. En la última década se han informado casos graves de compromiso visceral por toxoplasmosis aguda en pacientes inmunocompetentes. En este artículo se presenta un brote epidémico causado por Toxoplasma gondii en personal militar durante el desarrollo de operaciones de selva en el área general de La Macarena, Meta, Colombia. Los 18 casos reportados se confirmaron mediante inmunofluorescencia indirecta (IFI de anticuerpos IgG anti-toxoplasma, al obtener títulos iguales o superiores a 1:1.024 (valor negativo inferior a 1:16. Los síntomas más importantes en estos pacientes fueron fiebre prolongada, adenopatías y compromiso pulmonar y gastrointestinal. Un paciente desarrolló compromiso miopericárdico grave. Todos los pacientes se recuperaron después de tratamiento con pirimetamina/sulfodaxina y clindamicina durante tres semanas. Una hipótesis para la presentación del brote epidémico es el consumo de agua contaminada con ooquistes y, probablemente, la seriedad del compromiso puede atribuirse a una cepa silvestre del parásito, tal como se ha descrito en otros casos reportados en la literatura, aunque en nuestro caso en particular, no se pudo realizar el aislamiento y tipificación de las cepas involucradas.Toxoplasmosis is a common opportunistic infection in patients infected with HIV/AIDS while in immunocompetent patients this infection causes symptoms only in 10% to 20% of the cases, generally with a benign and autoresolutive course. In the last decade some severe cases with visceral involvement has been reported in immunocompetent patients, though they were isolated or recovered during years. We present the first Colombian

Internalization and Dissemination of Human Norovirus and Animal Caliciviruses in Hydroponically Grown Romaine Lettuce

Science.gov (United States)

DiCaprio, Erin; Ma, Yuanmei; Purgianto, Anastasia; Hughes, John

2012-01-01

Fresh produce is a major vehicle for the transmission of human norovirus (NoV) because it is easily contaminated during both pre- and postharvest stages. However, the ecology of human NoV in fresh produce is poorly understood. In this study, we determined whether human NoV and its surrogates can be internalized via roots and disseminated to edible portions of the plant. The roots of romaine lettuce growing in hydroponic feed water were inoculated with 1 × 106 RNA copies/ml of a human NoV genogroup II genotype 4 (GII.4) strain or 1 × 106 to 2 × 106 PFU/ml of animal caliciviruses (Tulane virus [TV] and murine norovirus [MNV-1]), and plants were allowed to grow for 2 weeks. Leaves, shoots, and roots were homogenized, and viral titers and/or RNA copies were determined by plaque assay and/or real-time reverse transcription (RT)-PCR. For human NoV, high levels of viral-genome RNA (105 to 106 RNA copies/g) were detected in leaves, shoots, and roots at day 1 postinoculation and remained stable over the 14-day study period. For MNV-1 and TV, relatively low levels of infectious virus particles (101 to 103 PFU/g) were detected in leaves and shoots at days 1 and 2 postinoculation, but virus reached a peak titer (105 to 106 PFU/g) at day 3 or 7 postinoculation. In addition, human NoV had a rate of internalization comparable with that of TV as determined by real-time RT-PCR, whereas TV was more efficiently internalized than MNV-1 as determined by plaque assay. Taken together, these results demonstrated that human NoV and animal caliciviruses became internalized via roots and efficiently disseminated to the shoots and leaves of the lettuce. PMID:22729543

Estudio comparativo del crecimiento y la ramificación de brotes anuales en dos especies de Nothofagus (Nothofagaceae y en híbridos inter-específicos Comparative study of annual shoot growth and branching in two species of Nothofagus (Nothofagaceae and inter-specific hybrids

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Cristian Torres

2009-12-01

Full Text Available Las ramas principales y secundarias se diferencian en mayor o menor medida según las especies, lo cual puede observarse en base al crecimiento primario de los brotes que las originan. En ejemplares de vivero juveniles-adultos de Nothofagus obliqua, N. nervosa e híbridos entre ambas especies, se compararon la dinámica de alargamiento, el tamaño y la morfología de dos brotes distales de ramas principales: uno que continúa el alargamiento de la rama principal y el otro que inicia una rama secundaria. En N. alpina y en híbridos, los dos brotes más distales se diferencian más que en N. obliqua. A pesar de la homogeneidad ambiental en el vivero y el origen geográfico común para los ejemplares de N. nervosa y los híbridos, hubieron diferencias fenológicas y morfológicas entre estas entidades. La duración y tasa de alargamiento y la longitud final de los brotes fueron altamente variables en cada entidad. Las variaciones entre entidades en la diferenciación de ejes podrían indicar diferencias en sus capacidades de uso del espacio circundante. La diferenciación entre ramas principales y secundarias se iniciaría en el estado de yema. La variación intra-específica fenológica y morfológica es útil para programas de selección artificial de individuos.Main and secondary branches are more or less differentiated according to the species and this could be observed during the primary growth of the shoots that produce them. In young-adult trees of Nothofagus obliqua, N. nervosa and hybrids between them growing in a common garden, growth dynamics, size and morphology were compared between two distal shoots produced by main branches: one of these shoots continued the extension of the main branch whereas the other initiated a secondary branch. The two distal shoots differed from each other more notably in N. nervosa and in the hybrids than in N. obliqua. Despite the environmental homogeneities at the nursery and the common geographic origin of

Comparative Inactivation of Murine Norovirus, Human Adenovirus, and Human JC Polyomavirus by Chlorine in Seawater

Science.gov (United States)

de Abreu Corrêa, Adriana; Carratala, Anna; Barardi, Celia Regina Monte; Calvo, Miquel; Bofill-Mas, Sílvia

2012-01-01

Viruses excreted by humans affect the commercial and recreational use of coastal water. Shellfish produced in contaminated waters have been linked to many episodes and outbreaks of viral gastroenteritis, as well as other food-borne diseases worldwide. The risk can be reduced by appropriate treatment following harvesting and by depuration. The kinetics of inactivation of murine norovirus 1 and human adenovirus 2 in natural and artificial seawater by free available chlorine was studied by quantifying genomic copies (GC) using quantitative PCR and infectious viral particles (PFU). Human JC polyomavirus Mad4 kinetics were evaluated by quantitative PCR. DNase or RNase were used to eliminate free genomes and assess potential viral infectivity when molecular detection was performed. At 30 min of assay, human adenovirus 2 showed 2.6- and 2.7-log10 GC reductions and a 2.3- and 2.4-log10 PFU reductions in natural and artificial seawater, respectively, and infectious viral particles were still observed at the end of the assay. When DNase was used prior to the nucleic acid extraction the kinetic of inactivation obtained by quantitative PCR was statistically equivalent to the one observed by infectivity assays. For murine norovirus 1, 2.5, and 3.5-log10 GC reductions were observed in natural and artificial seawater, respectively, while no viruses remained infectious after 30 min of contact with chlorine. Regarding JC polyomavirus Mad4, 1.5- and 1.1-log10 GC reductions were observed after 30 min of contact time. No infectivity assays were conducted for this virus. The results obtained provide data that might be applicable to seawater used in shellfish depuration. PMID:22773637

Virus sincicial respiratorio: presentación, manejo y prevención de un brote intrahospitalario en una unidad de cuidados intensivos neonatales de Lima

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T Paredes

2012-01-01

Full Text Available El virus sincicial respiratorio (VSR es el principal patógeno causante de infecciones del tracto respiratorio bajo durante el primer año de vida y ocasiona un elevado índice de hospitalización en niños menores de 12 meses; la presentación clínica severa y su aparición como brotes epidemiológicos en las unidades con recién nacidos prematuros representa un riesgo elevado de morbimortalidad. Se realiza la presentación de dos casos y el análisis sobre la importancia del diagnóstico precoz, el manejo individualizado y las medidas de control de infecciones como factores que reducen la morbimortalidad en estas situaciones y previenen la diseminación de los casos en una unidad de cuidados intensivos neonatales (UCIN.

Detection of Pathogenic Viruses in Sewage Provided Early Warnings of Hepatitis A Virus and Norovirus Outbreaks

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Hellmér, Maria; Paxéus, Nicklas; Magnius, Lars; Enache, Lucica; Arnholm, Birgitta; Johansson, Annette; Bergström, Tomas

2014-01-01

Most persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care. PMID:25172863

Immunomagnetic separation combined with RT-qPCR for determining the efficacy of disinfectants against human noroviruses

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Pengbo Liu

2015-03-01

Full Text Available Summary: Little is known about the effectiveness of disinfectants against human noroviruses (NoV partially because human NoV cannot be routinely cultured in laboratory. The objective of this study was to develop a NoV monoclonal antibody-conjugated immunomagnetic separation (IMS procedure combined with real-time reverse transcription polymerase chain reaction (RT-qPCR assays to study the in vitro efficacy of disinfectants against human NoV. Monoclonal antibodies against Norwalk virus (NV, GI.1 and NoV GII.4 were produced using unique NoV capsid proteins, and the antibodies were conjugated to magnetic Dynalbeads. The immunomagnetic beads were used to simultaneously capture intact NoV in samples and effectively remove PCR inhibitors. We examined the efficacy of ethanol, sodium hypochlorite, nine commercially available disinfectants, and one prototype disinfectant using the IMS/RT-qPCR. The sensitivity of this procedure was approximately 100 virus particles for both the NV and GII.4 viruses. The average log reductions in in vitro activities varied between disinfectants. The prototype disinfectant produced an average 3.19-log reduction in NV and a 1.38-log reduction in GII.4. The prototype disinfectant is promising of inactivating NoV. This method can be used to evaluate in vitro activity of disinfectants against human NoV. The IMS/RT-qPCR method is promising as an effective method to remove PCR inhibitors in disinfectants and enable the evaluation of the efficacy of disinfectants. Keywords: Disinfectant, Norovirus, Immunomagnetic separation, Real-time RT-PCR, PCR inhibition

en la provincia de Almería en el año 2005

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Pilar Barroso García

2007-01-01

Full Text Available 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 inicio de síntomas, sintomatología, complicaciones, situación vacunal, cepa vacunal y pruebas diagnósticas. Fuentes de información: fichas de declaración de enfermedad, encuestas epidemiológicas, información microbiológica, cartilla de vacunaciones, aplicación informática de vacunas del Distrito y datos demográficos del IEA. Se calcularon tasas por 100.000 habitantes por grupos de edad y tipo de población. Para comparar medias se utilizó la t de Student. Resultados: Se notificaron 145 casos procedentes de 17 municipios. El 63,4% fueron varones. El grupo con mayor incidencia fue el de 10 a 14 años con una tasa de 405 por 100.000. La tasa más alta se dio en población autóctona (128,7. En el 52,4% de los casos se comprobó que habían recibido alguna dosis de vacuna, de ellos 69,7% con dos dosis y el 71,1% alguna cepa de Jeryl Lynn. Se confirmó virus de parotiditis en 43 casos, en 6 se identificó genotipo G1. Conclusiones: Se confirma brote por virus de la parotiditis genotipo G1, con mayor afectación de población autóctona de diferentes grupos de edad. Más de la mitad de los casos fueron personas vacunadas.

Norovirus translation requires an interaction between the C Terminus of the genome-linked viral protein VPg and eukaryotic translation initiation factor 4G.

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Chung, Liliane; Bailey, Dalan; Leen, Eoin N; Emmott, Edward P; Chaudhry, Yasmin; Roberts, Lisa O; Curry, Stephen; Locker, Nicolas; Goodfellow, Ian G

2014-08-01

Viruses have evolved a variety of mechanisms to usurp the host cell translation machinery to enable translation of the viral genome in the presence of high levels of cellular mRNAs. Noroviruses, a major cause of gastroenteritis in man, have evolved a mechanism that relies on the interaction of translation initiation factors with the virus-encoded VPg protein covalently linked to the 5' end of the viral RNA. To further characterize this novel mechanism of translation initiation, we have used proteomics to identify the components of the norovirus translation initiation factor complex. This approach revealed that VPg binds directly to the eIF4F complex, with a high affinity interaction occurring between VPg and eIF4G. Mutational analyses indicated that the C-terminal region of VPg is important for the VPg-eIF4G interaction; viruses with mutations that alter or disrupt this interaction are debilitated or non-viable. Our results shed new light on the unusual mechanisms of protein-directed translation initiation. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Blood Group Substances as Potential Therapeutic Agents for the Prevention and Treatment of Infection with Noroviruses Proving Novel Binding Patterns in Human Tissues

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Yazawa, Shin; Yokobori, Takehiko; Ueta, Gen; Ide, Munenori; Altan, Bolag; Thongprachum, Aksara; Nishimura, Toyo; Nakajima, Tamiko; Kominato, Yoshihiko; Asao, Takayuki; Saniabadi, Abby R.; Furukawa, Kiyoshi; Kuwano, Hiroyuki; Le Pendu, Jacques; Ushijima, Hiroshi

2014-01-01

Blood group-related glycans determining ABO and Lewis blood groups are known to function as attachment factors for most of the norovirus (NoV) strains. To identify binding specificity of each NoV, recombinant norovirus-like particles (VLPs) and human saliva samples with different ABO, Lewis phenotypes and secretor status have been commonly applied. When binding specificities of VLPs prepared from 16 different genotypes of NoVs in GI and GII genogroups were characterized in samples of human gastric mucosa compared to human saliva based on blood group phenotypes, considerable differences were observed for several strains. Novel binding specificities determined by an ELISA using preparations from human gastric mucosa were also ascertained by immunohistochemical analyses using human jejunal mucosa, widely believed to be susceptible to NoV infection. Further, A, B and O(H) blood group substances prepared from porcine and squid tissues were found to be effective for preventing ABO blood group-specific binding of VLPs to both saliva and mucosa samples. Therefore, these blood group substances might have potential for the prevention and treatment of NoV infection. PMID:24558470

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

Posible transmisión oral de la enfermedad de Chagas en trabajadores del sector de los hidrocarburos en Casanare, Colombia, 2014

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Liliana Patricia Zuleta-Dueñas

2017-06-01

Conclusiones. Mediante el análisis de las características epidemiológicas, ambientales y sanitarias, se confirmó un brote agudo de enfermedad de Chagas por exposición ocupacional y de posible transmisión oral, que podría ser el de mayor proporción reportado hasta la fecha en Colombia.

Control of norovirus outbreak on a pediatric oncology unit.

Science.gov (United States)

Sheahan, Anna; Copeland, Gretchen; Richardson, Lauren; McKay, Shelley; Chou, Alexander; Babady, N Esther; Tang, Yi-Wei; Boulad, Farid; Eagan, Janet; Sepkowitz, Kent; Kamboj, Mini

2015-10-01

Patients undergoing treatment for cancer with chemotherapy and hematopoietic stem cell recipients are at risk for severe morbidity caused by norovirus (NV). We describe a NV outbreak on the Memorial Sloan Kettering Cancer Center's pediatric oncology unit. Stool testing for diagnosis of NV was performed by real-time polymerase chain reaction (PCR). Twelve NV cases occurred; 7 were hospital acquired. Twenty-five health care workers reported NV compatible illness. Patient-to-patient transmission occurred once. The practices of the Centers for Disease Control and Prevention were supplemented with electronic surveillance, surrogate screening for NV, and heightened cleaning. Two additional cases occurred after implementation of interventions. Long-term shedding was detected in 2 patients. We describe interventions for controlling NV on a pediatric oncology unit. High-risk chronic shedders pose ongoing transmission risks. PCR is a valuable diagnostic tool but may be overly sensitive. Surrogate markers to assess NV burden in stool and studies on NV screening are needed to develop guidelines for high-risk chronic shedders. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Influenza. Vacunas clásicas y novedosas a las puertas de otra pandemia

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Raiza Martínez

2006-08-01

Full Text Available Los virus de la influenza A, además del hombre, infectan otros mamíferos y una gran variedad de especies de aves. Desde 1997 se sabe que cepas aviares son capaces de infectar al hombre provocando una enfermedad generalmente leve. El brote actual de gripe aviar H5N1 en humanos ha puesto en alerta a la comunidad científica internacional, no solo por su elevada mortalidad sino por su potencialidad en la generación de una nueva pandemia. Las autoridades sanitarias han puesto en marcha un amplio programa para la preparación ante esta contingencia, que abarca diferentes campos, desde el diagnóstico y la detección precoz de los brotes tanto en animales como en humanos, la caracterización sistemática de las cepas circulantes, el sacrificio de aves infectadas, la producción masiva de antivirales y por supuesto el desarrollo y producción a gran escala de vacunas eficaces. En este último tema se trabaja intensamente tanto en el mejoramiento de las vacunas ya existentes como en la búsqueda de alternativas basadas en tecnologías de nueva generación.

EFFECT OF BAP AND IAA ON SHOOT REGENERATION IN COTYLEDONARY EXPLANTS OF COSTA RICAN MELON GENOTYPES

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Marta Valdez Melara

2009-01-01

Full Text Available Para establecer una metodología para la regeneración del melón criollo (Cucumis melo L, se investigó la influencia del genotipo (OSO-1, OSO-2, OSO- 3, PQRG-1, PQRG-2, PQRG-3, y EM-1 y la interacción de N6-bencilaminopurina (BAP (0,1, 0,5 y 1,0 mg.l-1 con ácido indolacético (AIA (0, 0,05 y 0,5 mg.l-1 en la inducción de brotes y regeneración de plantas. Independientemente de la concentración de BAP y AIA, el mayor porcentaje de formación de brotes se obtuvo en EM-1>OSO-1>PQRG-3>OSO-2>PQRG-2>PQRG-1>OSO-3. Por otra parte, independientemente del genotipo, el mayor porcentaje de formación de brotes se obtuvo con 0,5 mg.l-1 BAP y 0,05 mg.l-1 AIA o 1 mg.l-1 BAP y 0 mg.l-1 AIA. El protocolo de cultivo in vitro establecido puede ser utilizado para la micropropagación de genotipos "criollos" de melón.

Epidemiologia de la fiebre amarilla selvática en Colombia durante los últimos años

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Jorge Boshell Manrique

1944-08-01

Full Text Available La primera manifestación de Fiebre Amarilla Selvática en los Llanos Orientales de Colombia se registro en agosto de 1934 en forma de un brote epidémico en la vecindad de la población de Restrepo, y se prolongó hasta febrero de 1935 (1. En la segunda mitad del mismo año la enfermedad apareció en los alrededores de Villavicencio y Acacías; en los últimos meses de 1936 se registraron casos en las tres regiones. Nuevas manifestaciones se presentaron en 1937 en el curso inferior de los ríos correspondientes a tales regiones, seguidas por un silencio que se prolongó hasta 1940, año en que principió el brote actual. No hubo explicación satisfactoria respecto al origen del brote de 1934. Era evidente que la infección atacaba de preferencia a los peones que trabajaban en el bosque. En ningún sitio de toda esa región, a pesar de larga y cuidadosa búsqueda, fue posible encontrar larvas o adultos de Aedes aegypti.

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-log 10 MS2 reduction by PAA and monochloramine in MWW were 1254 and 1228 mg-min/L, respectively. The 1-, 2-, and 3-log 10 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.

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)

DEFF Research Database (Denmark)

Hald, Tine; Baggesen, Dorte Lau

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 Norovirus occurrence in tomatoes 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 tomato 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 tomato producers. The current lack of data does not allow the proposal of a Hygiene Criterion for E. coli at primary production of tomatoes and it is also not possible to assess...

Aqueous Extracts of Hibiscus sabdariffa Calyces Decrease Hepatitis A Virus and Human Norovirus Surrogate Titers.

Science.gov (United States)

Joshi, Snehal S; Dice, Lezlee; D'Souza, Doris H

2015-12-01

Hibiscus sabdariffa extract is known to have antioxidant, anti-diabetic, and antimicrobial properties. However, their effects against foodborne viruses are currently unknown. The objective of this study was to determine the antiviral effects of aqueous extracts of H. sabdariffa against human norovirus surrogates (feline calicivirus (FCV-F9) and murine norovirus (MNV-1)) and hepatitis A virus (HAV) at 37 °C over 24 h. Individual viruses (~5 log PFU/ml) were incubated with 40 or 100 mg/ml of aqueous hibiscus extract (HE; pH 3.6), protocatechuic acid (PCA; 3 or 6 mg/ml, pH 3.6), ferulic acid (FA; 0.5 or 1 mg/ml; pH 4.0), malic acid (10 mM; pH 3.0), or phosphate buffered saline (pH 7.2 as control) at 37 °C over 24 h. Each treatment was replicated thrice and plaque assayed in duplicate. FCV-F9 titers were reduced to undetectable levels after 15 min with both 40 and 100 mg/ml HE. MNV-1 was reduced by 1.77 ± 0.10 and 1.88 ± 0.12 log PFU/ml after 6 h with 40 and 100 mg/ml HE, respectively, and to undetectable levels after 24 h by both concentrations. HAV was reduced to undetectable levels by both HE concentrations after 24 h. PCA at 3 mg/ml reduced FCV-F9 titers to undetectable levels after 6 h, MNV-1 by 0.53 ± 0.01 log PFU/ml after 6 h, and caused no significant change in HAV titers. FA reduced FCV-F9 to undetectable levels after 3 h and MNV-1 and HAV after 24 h. Transmission electron microscopy showed no conclusive results. The findings suggest that H. sabdariffa extracts have potential to prevent foodborne viral transmission.

Brote de leptospirosis en terneros en recría en la provincia de Corrientes, Argentina Leptospirosis outbreak in calves from Corrientes Province, Argentina

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María G. Draghi

2011-03-01

Full Text Available La leptospirosis es una enfermedad infecciosa que produce importantes pérdidas económicas en la producción ganadera. Los signos característicos de la enfermedad son aborto, muerte embrionaria, muerte de terneros de pocos días de vida y mastitis. Se describe un brote de leptospirosis en terneros en actividad de recría. Se realizaron estudios histopatológicos, de hemoparásitos, inmunofluorescencia y cultivos bacterianos. Se aisló Leptospira interrogans serovar Pomona a partir de muestras de los terneros muertos.Leptospirosis is an infectious disease resulting in significant economic losses in livestock production. This disease causes abortion, embryo death, death of calves within the first few days of life and mastitis. We report a leptospirosis outbreak in calf growing and fattening. Histopathological and hemoparasite studies, immunofluorescence, and bacterial cultures were performed. A strain of Leptospira interrogans serovar Pomona was isolated from samples collected from dead calves.

Economic costs of outbreaks of acute viral gastroenteritis due to norovirus in Catalonia (Spain), 2010-2011.

Science.gov (United States)

Navas, Encarna; Torner, Nuria; Broner, Sonia; Godoy, Pere; Martínez, Ana; Bartolomé, Rosa; Domínguez, Angela

2015-10-01

To determine the direct and indirect costs of outbreaks of acute viral gastroenteritis (AVG) due to norovirus in closed institutions (hospitals, social health centers or nursing homes) and the community in Catalonia in 2010-11. Information on outbreaks were gathered from the reports made by epidemiological surveillance units. Direct costs (medical visits, hospital stays, drug treatment, sample processing, transport, diagnostic tests, monitoring and control of the outbreaks investigated) and indirect costs (lost productivity due to work absenteeism, caregivers time and working hours lost due to medical visits) were calculated. Twenty-seven outbreaks affecting 816 people in closed institutions and 74 outbreaks affecting 1,940 people in the community were detected. The direct and indirect costs of outbreaks were € 131,997.36 (€ 4,888.79 per outbreak) in closed institutions and € 260,557.16 (€ 3,521.04 per outbreak) in community outbreaks. The cost per case was € 161.76 in outbreaks in closed institutions and € 134.31 in community outbreaks. The main costs were surveillance unit monitoring (€ 116,652.93), laboratory diagnoses (€ 119,950.95), transport of samples (€ 69,970.90), medical visits (€ 25,250.50) and hospitalization (€ 13,400.00). The cost of outbreaks of acute viral gastroenteritis due to norovirus obtained in this study was influenced by the number of people affected and the severity of the outbreak, which determined hospitalizations and work absenteeism. Urgent reporting of outbreaks would allow the implementation of control measures that could reduce the numbers affected and the duration of the illness and thus the costs derived from them.

MICROPROPAGACIÓN DE CUATRO CULTIVARES DE ARÁNDANO (Vaccinium spp. A PARTIR DE SEGMENTOS FOLIARES DE DOS PROCEDENCIAS

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Arturo Brenes Angulo

2015-01-01

Full Text Available Los cultivares de arándano Sharpblue, Woodard, Bonita y Delite se propagaron a partir de secciones de hoja procedentes de explantes uninodales establecidos in vitro y de secciones de hoja directamente del campo. Los explantes se colocaron en medio WPM suplementado con 1, 5 mg.l -1 de TDZ para promover la brotación; luego se subcultivaron a medio fresco WPM suplementado con 0,5 ó 1,0 mg.l -1 de Zeatina, para promover el crecimiento de los brotes. Se determinó la longitud de la micromacolla y el número de brotes >2mm y >1cm por microma - colla. Brotes de 8-10 cm se cosecharon a las 8 semanas y se subcultivaron en WPM suple - mentado con 0, 1, 2, 4 u 8 mg.l -1 de AIB, para promover su enraizamiento; a las 10 semanas se trasplantaron a invernadero para aclimatización. Al cultivar los segmentos foliares en WPM con 1, 5 mg.l -1 de TDZ se formaron micromacollas en todas las variedades, independientemente de la procedencia de la hoja, con un efecto significati - vo del cultivar, la procedencia, del explante y la interacción cultivar x procedencia, para el núme - ro de brotes >2 mm obtenidos. El tamaño de la micromacolla varió significativamente según cultivares, procedencia del explante e interacción cultivares x procedencia x concentración de zea - tina, al trasferirse a un medio con 2 concentracio - nes del regulador de crecimiento, pero no hubo diferencias con respecto a éstas. El número de brotes > 2mm y la longitud del más largo variaron significativamente con el cultivar, y la interacción cultivar x procedencia del explante en WPM con 0,5 mg.l -1 de Zeatina. Explantes de Woodard a partir de vitrohoja produjeron el mayor número de brotes (44,70±13,34 y Delite de vitrohoja el menor (21,50±4,99. Los brotes subcultivados en WPM con diferentes concentraciones de AIB mostraron enraizamiento menor al 10% en todos los tratamientos. Sin embargo, al trasplantarse a invernadero se obtuvo 100% de enraizamiento, independientemente del

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

of infectious virus and viral genomes were determined by plaque assay and reverse transcription-real time quantitative PCR (RT-qPCR), respectively. On plastic surfaces, an inactivation of >99.99% was obtained for both MS2 and FCV, corresponding to a 9.1-log and >4.8-log reduction after 1 or 3 s of treatment......) resulted in negligible reductions of viral genome titers of MS2, FCV, and MNV on plastic surfaces as well as of MS2 inoculated on raspberries. Steam-ultrasound treatment in its current format does not appear to be an appropriate method to achieve sufficient decontamination of NoV-contaminated raspberries...... 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...

Construction and Cloning of Reporter-Tagged Replicon cDNA for an In Vitro Replication Study of Murine Norovirus-1 (MNV-1).

Science.gov (United States)

Ahmad, Muhammad Khairi; Tabana, Yasser M; Ahmed, Mowaffaq Adam; Sandai, Doblin Anak; Mohamed, Rafeezul; Ismail, Ida Shazrina; Zulkiflie, Nurulisa; Yunus, Muhammad Amir

2017-12-01

A norovirus maintains its viability, infectivity and virulence by its ability to replicate. However, the biological mechanisms of the process remain to be explored. In this work, the NanoLuc™ Luciferase gene was used to develop a reporter-tagged replicon system to study norovirus replication. The NanoLuc™ Luciferase reporter protein was engineered to be expressed as a fusion protein for MNV-1 minor capsid protein, VP2. The foot-and-mouth disease virus 2A (FMDV2A) sequence was inserted between the 3'end of the reporter gene and the VP2 start sequence to allow co-translational 'cleavage' of fusion proteins during intracellular transcript expression. Amplification of the fusion gene was performed using a series of standard and overlapping polymerase chain reactions. The resulting amplicon was then cloned into three readily available backbones of MNV-1 cDNA clones. Restriction enzyme analysis indicated that the NanoLucTM Luciferase gene was successfully inserted into the parental MNV-1 cDNA clone. The insertion was further confirmed by using DNA sequencing. NanoLuc™ Luciferase-tagged MNV-1 cDNA clones were successfully engineered. Such clones can be exploited to develop robust experimental assays for in vitro assessments of viral RNA replication.

Prevalencia de las infecciones por virus de las hepatitis B, C, D y E en Bolivia Prevalence of viral hepatitis B, C, D, and E in Bolivia

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Pilar León

1999-03-01

,6%, la ausencia de ADN vírico en las muestras con reactividad aislada a anti-HBc y la alta prevalencia de anti-HBs entre los individuos que presentan marcadores de infección natural (92,4% excluyen la participación de la transmisión vertical en el mantenimiento de la endemia. Hasta el momento, no se ha documentado ningún brote de infección por VHD en estas comunidades, pero la alta endemia de infección por VHB alerta sobre el riesgo de posibles brotes en el futuro. Los resultados obtenidos con las pruebas de anticuerpos contra VHE sugieren que este virus circula ampliamente en Bolivia y que podría haber producido brotes recientes en el departamento de Cochabamba. Se recomienda vacunar contra VHB en las poblaciones endémicas como medida de corto plazo; buscar activamente en todo el país brotes y casos esporádicos de hepatitis E y continuar realizando estudios que permitan evaluar las repercusiones sanitarias de la situación documentada en este estudio.In Bolivia, no studies have been carried out specifically on hepatitis viruses. Thus, their prevalence and circulation patterns are virtually unknown. A seroepidemiologic study was performed from 1992 to 1996 to generate a preliminary idea of the overall prevalence of infection from hepatitis B, C, D, and E viruses (HBV, HCV, HDV, and HEV, respectively in different Bolivian population groups. Prompted by the data obtained in other areas of Latin America, the study focused on indigenous communities in the Amazon region. In rural areas of the high Andean plateau, HBV infection showed an overall prevalence compatible with medium to low endemicity (11.2%, and no carriers of HCV or HDV antibodies were found. In two high-risk groups in the city of Cochabamba (homeless children and sexual workers, the prevalence of HBV infection was similar (11.6% and could be considered low by comparison to that of similar population groups in Latin American urban centers. The prevalence of HCV (one positive case, or 0.5% was similar

Valoración de métodos convencionales y no convencionales para el control del taladrador de las meliáceas en América

OpenAIRE

Ruiz, Bayron Alexander; Tamayo, Juan Carlos; Martínez, Melida; Medina, Henry Hernán; Salcedo, Eduardo; Hernández, Efrén; Palacios, Carlos Alexis; Silva, José Antonio; González, Ricardo

2016-01-01

En el presente artículo de revisión se hace una recapitulación de investigaciones recientes que se han realizado con el propósito de disminuir el efecto negativo producido por los insectos Hypsipyla grandella e Hypsipyla robusta (taladrador de los brotes tiernos) en plántulas pertenecientes a la familia de las meliáceas, destacando la caoba (Swietenia macrophylla) y el cedro (Cedrela odorata), consideradas de suma importancia comercial por su estructura y calidad de la madera en la industria ...

Chicungnya, CHIKV, Chikungunya o Chicunguña

OpenAIRE

Ramírez-Tamayo, Amparo Aurora; Olivella-Jacquín, Juan Luciano

2016-01-01

El aula de clase, la investigación y el momento que vive Colombia con una enfermedad denominada Chicunguña o Chicungunya fueron las grandes herramientas para conocer en qué consiste y por qué los pacientes se sienten desprotegidos, desesperados, sin respuesta a una enfermedad por la cual solamente reciben como medicamento acetaminofén y muchas recomendaciones de quienes la han padecido o la han acompañado. Dolor en todo el cuerpo, cojera, manos hinchadas, brote tipo varicela, son algunos de l...

Group A rotavirus and norovirus display sharply distinct seasonal profiles in Belém, northern Brazil

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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.

EPA Method 1615. Measurement of Enterovirus and Norovirus ...

Science.gov (United States)

A standardized method is required when national studies on virus occurrence in environmental and drinking waters utilize multiple analytical laboratories. The U.S Environmental Protection Agency’s (USEPA) Method 1615 was developed with the goal of providing such a standard for measuring Enterovirus and Norovirus in these waters. Virus is concentrated from water using an electropositive filter, eluted from the filter surface with beef extract, and then concentrated further using organic flocculation. Herein we present the protocol from Method 1615 for filter elution, secondary concentration, and measurement of total culturable viruses. A portion of the concentrated eluate from each sample is inoculated onto ten replicate flasks of Buffalo Green Monkey kidney cells. The number of flasks demonstrating cytopathic effects is used to quantify the most probable number (MPN) of infectious units per liter. The method uses a number of quality controls to increase data quality and to reduce interlaboratory and intralaboratory variation. Laboratories must meet defined performance standards. Method 1615 was evaluated by examining virus recovery from reagent-grade and ground waters seeded with Sabin poliovirus type 3. Mean poliovirus recoveries with the total culturable assay were 111% in reagent grade water and 58% in groundwaters. EPA Method 1615 is being used by a number of national and international labs. This paper and the accompanying video will provide training oppo

Factores de riesgo asociados a infección aguda por hepatitis B en población militar destacada al departamento de Amazonas, Perú

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César Cabezas

2007-10-01

Full Text Available El Perú es considerado un país de endemicidad intermedia-alta para el virus de hepatitis B (VHB, con variaciones entre diferentes regiones. Existen pocos reportes del problema de infección por el VHB en personal militar. Objetivos. Determinar los factores de riesgo asociados con el desarrollo de infección por el VHB en un brote epidémico en personal militar destacado en Ampama, Amazonas, Perú. Material y métodos. Estudio caso-control en personal militar destacado al puesto de Ampama y a la base El Milagro, departamento de Amazonas. Fueron evaluados HBsAg y posibles factores de riesgo asociados a un incremento de riesgo de adquirir el VHB. Resultados. Se estudió a 123 personas, repartidos en 41 sujetos en cada uno de los grupos (casos, control 1 y control 2. 73,2% de los casos tuvo confirmación de infección aguda por el VHB (IgM anti HBc positivo y anti Delta fue positivo en 1/37 (2,7% caso. Ninguno de los factores de riesgo evaluados mostró una asociación significativa con hepatitis B. Algunos factores de riesgo con posible asociación fueron contacto con personal con hepatitis B (OR 2,3; IC95% 0,9 - 5,7 y mordedura de murciélago (OR 1,6; IC95% 0,6 - 4,4. Conclusiones. Los factores de riesgo clásicos asociados con la transmisión del virus de la hepatitis B no fueron significativos. El personal militar es un grupo en riesgo para infectarse con el VHB.

Survival and inactivation of human norovirus surrogates in blueberry juice by high-pressure homogenization.

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Horm, Katie Marie; Davidson, P Michael; Harte, Federico M; D'Souza, Doris Helen

2012-11-01

Human noroviruses (HNoV) have been implicated in gastrointestinal outbreaks associated with fresh produce, juices, and ready-to-eat foods. In order to determine the risk of HNoV transmission by contaminated blueberry juice, survival characteristics of cultivable HNoV surrogates (murine norovirus, MNV-1; feline calicivirus, FCV-F9; and bacteriophage MS2) in blueberry juice (pH = 2.77) after 0, 1, 2, 7, 14, and 21 days at refrigeration temperatures (4°C) were studied. High-pressure homogenization (HPH) was studied as a novel processing method for noroviral surrogate inactivation in blueberry juice. Blueberry juice or phosphate-buffered saline (PBS; pH 7.2 as control) was inoculated with each virus, stored over 21 days at 4°C or subjected to HPH, and plaque assayed. FCV-F9 (∼5 log(10) PFU/mL) was undetectable after 1 day in blueberry juice at 4°C. MNV-1 (∼4 log(10) PFU/ml) showed minimal reduction (1 log(10) PFU/mL) after 14 days, with greater reduction (1.95 log(10) PFU/mL; p PFU/mL) showed significant reduction (1.93 log(10) PFU/mL; p PFU/mL reduction), while MNV-1 and MS2 survived after 21 days (1.08 and 0.56 log(10) PFU/mL reduction, respectively). Intriguingly, FCV-F9 and bacteriophage MS2 showed reduction after minimal homogenization pressures in blueberry juice (pH = 2.77), possibly due to the combination of juice pH, juice components, and mechanical effects. MNV-1 in blueberry juice was only slightly reduced at 250 (0.33 log(10) PFU/mL) and 300 MPa (0.71 log(10) PFU/mL). Virus surrogate survival in blueberry juice at 4°C correlates well with the ease of HNoV transmission via juices. HPH for viral inactivation in juices is dependent on virus type, and higher homogenization pressures may be needed for MNV-1 inactivation.

Brote de intoxicación alimentaria asociado al consumo de leche ultrapasteurizada en la República del Paraguay Foodborne outbreak associated with consumption of ultrapasteurized milk in the Republic of Paraguay

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Natalie Weiler

2011-03-01

Full Text Available Durante marzo de 2007 ocurrió un brote epidémico asociado al consumo de leche ultrapasteurizada que afectó a las ciudades de San Lorenzo, Ciudad del Este y Asunción, de la República del Paraguay. Las personas afectadas fueron 400, de las cuales 60 requirieron hospitalización. Se aisló S. aureus subespecie aureus de 5 pacientes, 3 operarios y 3 muestras de leche. Todas las cepas fueron productoras de enterotoxinas. Las aislamientos de 3 pacientes, de un operario y de las muestras de leche portaron los genes que codifican las enterotoxinas C (sec y D (sed, y presentaron un patrón único de macrorrestricción (SmaI-PFGE. Se identificó a la leche como fuente de intoxicación y a un operario de la línea de producción como origen de la contaminación. Este es el primer brote de ETA denunciado en Paraguay en el cual se pudo aislar, caracterizar y subtipificar el agente etiológico en la planta de elaboración, en el alimento y en las personas afectadas.During March 2007 there was an epidemic outbreak associated with the consumption of ultrapasteurized milk. Four hundred people were affected and 60 required hospitalization. S. aureus subspecies aureus was isolated from 5 patients, 3 operators and 3 milk samples. All strains produced enterotoxins. Strains isolated from 3 patients, one operator and all the milk samples carried the genes encoding enterotoxins C (sec and D (sed, and showed an indistinguishable macrorestriction pattern (SmaI-PFGE. Milk was identified as the source of intoxication and a production line operator as the source of contamination. This is the first foodborne outbreak reported in Paraguay whose agent was isolated, characterized and subtypified in the production plant, the food and the affected people.

Murine Norovirus 4 (MNV-4 Infections Trigger Various Effects on Atherosclerosis Development

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Rafeezul Mohamed

2018-05-01

Full Text Available Murine norovirus (MNV infection can cause morbidity and mortality to immune compromised mice, especially colonies in research laboratory. MNV also can infect and propagates in macrophages and dendritic cells which trigger atherosclerosis development through the accumulation of these cells followed by the formation of foam cells. Recently, MNV-4 infection was associated with an increase in aortic sinus lesion size in LDLR (low-density lipoprotein receptor and ApoE (Apolipoprotein E deficient mice, both are well established mouse models for atherosclerosis research. Therefore, this review is intended to summarize the impacts of MNV infection in these two mouse models of atherosclerosis. The findings from all the related studies are important in understanding the fundamental effect of MNV infection on atherosclerosis development. In addition, this information could provide insight to researchers on the evaluation to eliminate MNV infection in research facility to avoid any unintended effect in their research, particularly in-vivo studies involving mice.

In vivo comparison of two human norovirus surrogates for testing ethanol-based handrubs: the mouse chasing the cat!

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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.

Fitting outbreak models to data from many small norovirus outbreaks

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Eamon B. O’Dea

2014-03-01

Full Text Available Infectious disease often occurs in small, independent outbreaks in populations with varying characteristics. Each outbreak by itself may provide too little information for accurate estimation of epidemic model parameters. Here we show that using standard stochastic epidemic models for each outbreak and allowing parameters to vary between outbreaks according to a linear predictor leads to a generalized linear model that accurately estimates parameters from many small and diverse outbreaks. By estimating initial growth rates in addition to transmission rates, we are able to characterize variation in numbers of initially susceptible individuals or contact patterns between outbreaks. With simulation, we find that the estimates are fairly robust to the data being collected at discrete intervals and imputation of about half of all infectious periods. We apply the method by fitting data from 75 norovirus outbreaks in health-care settings. Our baseline regression estimates are 0.0037 transmissions per infective-susceptible day, an initial growth rate of 0.27 transmissions per infective day, and a symptomatic period of 3.35 days. Outbreaks in long-term-care facilities had significantly higher transmission and initial growth rates than outbreaks in hospitals.

Internalization of Murine Norovirus 1 by Lactuca sativa during Irrigation ▿

Science.gov (United States)

Wei, Jie; Jin, Yan; Sims, Tom; Kniel, Kalmia E.

2011-01-01

Romaine lettuce (Lactuca sativa) was grown hydroponically or in soil and challenged with murine norovirus 1 (MNV) under two conditions: one mimicking a severe one-time contamination event and another mimicking a lower level of contamination occurring over time. In each condition, lettuce was challenged with MNV delivered at the roots. In the first case, contamination occurred on day one with 5 × 108 reverse transcriptase quantitative PCR (RT-qPCR) U/ml MNV in nutrient buffer, and irrigation water was replaced with virus-free buffer every day for another 4 days. In the second case, contamination with 5 × 105 RT-qPCR U/ml MNV (freshly prepared) occurred every day for 5 days. Virus had a tendency to adsorb to soil particles, with a small portion suspended in nutrient buffer; e.g., ∼8 log RT-qPCR U/g MNV was detected in soil during 5 days of challenge with virus inoculums of 5 × 108 RT-qPCR U/ml at day one, but sativa. PMID:21296944

Impacto del uso de piperacilina / tazobactam, sobre KPN resistente a ceftazidima en una unidad de cuidados intensivos neonatales

OpenAIRE

Mónica C. Mercado U.; Francisco Nápoles R.; María del Rayo Morfin O.; Eduardo Rodríguez N.; Pedro A. Martínez A.; Arturo Plascencia H.

2005-01-01

La frecuencia de resistencias a diversas bacterias mediadas por beta lactamasas de espectro extendido, varía ampliamente entre países, hospitales, tipo de unidad y tipo de paciente. Como medida de control para brotes de KPN, se estudió la sustitución de cefalosporinas de tercera generación en una UCI de población adulta con antibióticos β-lactámicos/inhibidores de β-lactamasas, entre ellos piperacilina/tazobactam. Se ha demostrado que al eliminar la presión ejercida por cef...

¿Está el mundo preparado para enfrentar una pandemía?

OpenAIRE

Oscar Rivera García

2006-01-01

Hay un sabio refrán que reza: “NO HAY MAL QUE POR BIEN NO VENGA”El “MAL” debe puntualizarse en los brotes de Influenza aviar presentados en Europa, África y Asia, que hasta la fecha, ha afectado a 258 personas de las cuales han muerto 153 infectadas por el virus H5N1 y ocasionado la muerte de mas de 200 millones de aves en estos tres continentes.Es Indonesia, el país más comprometido por el virus H5N1, con un total de 74 humanos infectados y 57 defunciones y se considera que este número de mu...

Procesos puntuales como herramienta para el análisis de posibles fuentes de contaminación

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Abellán J.J.

2002-01-01

Full Text Available El análisis de un patrón puntual engloba una serie de técnicas que permiten estudiar la distribución de un conjunto de eventos ocurridos sobre una región del plano. Este problema surge en epidemiología cuando se investiga una potencial fuente de contaminación ambiental alrededor de la cual se sospecha que surgen casos de una determinada enfermedad. En el presente trabajo, se explica brevemente en qué consiste el análisis de un patrón puntual y se ilustra con una aplicación a la determinación del origen medioambiental y al estudio de las zonas de mayor riesgo de incidencia en un brote de neumonía por Legionella ocurrido entre mediados de septiembre y principios de octubre en la ciudad de Alcoi (Alicante. El estudio permitió confirmar el origen medioambiental del brote y señalar las zonas de la ciudad con mayor riesgo, convirtiéndose en el argumento básico para llevar a cabo una exhaustiva inspección de las instalaciones generadoras de aerosoles, tras la cual, hasta la fecha, cesaron los brotes epidémicos.

Induction of homologous and cross-reactive GII.4-specific blocking antibodies in children after GII.4 New Orleans norovirus infection.

Science.gov (United States)

Blazevic, Vesna; Malm, Maria; Vesikari, Timo

2015-10-01

Noroviruses (NoVs) are major causative agents of acute gastroenteritis (AGE) in children worldwide and the most common viral cause of AGE in countries where rotavirus incidence has been eliminated by vaccination. Previous infections with the dominant GII.4 NoV genotype confer only partial protection against evolving immune escape variants that emerge every few years. The objective of this work was to investigate GII.4-specific homologous and cross-reactive antibody responses in young children after NoV GII.4-2009 New Orleans (NO) infection. Virus-like particles (VLPs) representing GII.4-1999, GII.4-2009 NO, and GII.4-2012 Sydney genotypes were used in ELISA and histo-blood group antigen blocking assays to examine acute and convalescent sera of five children <2 years of age infected with GII.4-2009 NO. GII.4-2009 NO infection induced IgG seroconversion to all three tested NoV GII.4 variants. Homologous blocking antibodies to GII.4-2009 NO were detected in each convalescent sera. Fourfold increase in cross-blocking antibodies to GII.4-2012 Sydney was observed in 4/5 subjects, but no child developed cross-blocking antibodies to GII.4-1999. In conclusion, antibodies induced in young children after norovirus GII.4 infection are targeted against the causative variant and may cross-protect against strains that are closely related, but not with more distinct and earlier GII.4 genotypes. © 2015 Wiley Periodicals, Inc.

Heat inactivation of a norovirus surrogate in cell culture lysate, abalone meat, and abalone viscera.

Science.gov (United States)

Park, Shin Young; Bae, San-Cheong; Ha, Sang-Do

2015-03-01

The current study examined the effects of temperature and heat treatment duration on murine norovirus-1 (MNV-1) from both viral cell culture lysate (7-8 log10 PFU) and experimentally contaminated abalone meat and viscera (5-6 log10 PFU) as a model of human norovirus (NoV). MNV-1 titers in cell culture lysate, abalone meat, and abalone viscera were gradually reduced to 1.93-4.55, 1.79-3.00, and 2.26-3.26 log10 PFU/ml, respectively, after treatment at 70 °C for 1-10 min. Treatment at 85 °C for 1-5 min gradually reduced MNV-1 titers in abalone meat to 2.71-4.15 log10 PFU/ml. MNV-1 titers in abalone viscera were gradually reduced to 2.91-3.46 log10 PFU/ml after treatment at 85 °C for 1-3 min. No significant difference (P > 0.05) was found in MNV-1 titers in the abalone meat and viscera among treatment groups (70 °C for 5 min, 70 °C for 3 min, and 85 °C for 1 min). Complete inactivation of MNV-1 in cell culture lysate was determined at 85 °C for ≥1 min and 100 °C for ≥0.5 min. Complete inactivation of MNV-1 in abalone was determined at 100 °C for ≥0.5 min for meat, and 85 °C for 5 min and 100 °C for ≥0.5 min for viscera. At treatments at 70 °C, the Td-values (3 log reduction time) were significantly lower (P abalone meat (6.07) and viscera (10.73). Td = 3 values were not significantly different (P > 0.05) between abalone meat (1.78) and abalone viscera (1.33) at treatments at 85 °C. This study suggests that 100 °C for ≥0.5 min could potentially be used to inactivate NoV in molluscan shellfishes, including viscera.

Reduction of Human Norovirus GI, GII, and Surrogates by Peracetic Acid and Monochloramine in Municipal Secondary Wastewater Effluent.

Science.gov (United States)

Dunkin, Nathan; Weng, ShihChi; Coulter, Caroline G; Jacangelo, Joseph G; Schwab, Kellogg J

2017-10-17

The objective of this study was to characterize human norovirus (hNoV) GI and GII reductions during disinfection by peracetic acid (PAA) and monochloramine in secondary wastewater (WW) and phosphate buffer (PB) as assessed by reverse transcription-qPCR (RT-qPCR). Infectivity and RT-qPCR reductions are also presented for surrogate viruses murine norovirus (MNV) and bacteriophage MS2 under identical experimental conditions to aid in interpretation of hNoV molecular data. In WW, RT-qPCR reductions were less than 0.5 log 10 for all viruses at concentration-time (CT) values up to 450 mg-min/L except for hNoV GI, where 1 log 10 reduction was observed at CT values of less than 50 mg-min/L for monochloramine and 200 mg-min/L for PAA. In PB, hNoV GI and MNV exhibited comparable resistance to PAA and monochloramine with CT values for 2 log 10 RT-qPCR reduction between 300 and 360 mg-min/L. Less than 1 log 10 reduction was observed for MS2 and hNoV GII in PB at CT values for both disinfectants up to 450 mg-min/L. Our results indicate that hNoVs exhibit genogroup dependent resistance and that disinfection practices targeting hNoV GII will result in equivalent or greater reductions for hNoV GI. These data provide valuable comparisons between hNoV and surrogate molecular signals that can begin the process of informing regulators and engineers on WW treatment plant design and operational practices necessary to inactivate hNoVs.

Aislamiento de Escherichia coli productor de toxina Shiga durante un brote de gastroenteritis en un Jardín Maternal de la Ciudad de Mar del Plata Isolation of Shiga toxin-producing Escherichia coli strains during a gastrointestinal outbreak at a day care center in Mar del Plata City

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D. Gomez

2005-12-01

Full Text Available Entre el 15 de octubre y el 8 de noviembre de 2003 ocurrió un brote de gastroenteritis en un Jardín Maternal de un Hospital de la ciudad de Mar del Plata. Catorce de un total de 80 niños (17,5%, edad promedio 23,6 ± 13,9 meses, presentaron diarrea, y un caso evolucionó a síndrome urémico hemolítico. La madre de uno de los afectados presentó diarrea simultáneamente. No se pudo establecer el origen del brote, pero probablemente la transmisión haya sido fundamentalmente persona a persona. Las prácticas habituales en el lactario del jardín maternal, y las condiciones inadecuadas de infraestructura y hábitos de higiene de la cocina del Hospital fueron señalados como factores de riesgo. En un caso se detectó Escherichia coli productor de toxina Shiga (STEC O103:H2, y STEC O26:H11 en otro. En el niño infectado por STEC O26:H11, la excreción se extendió por un período de 37 días. La no detección de STEC en aquellos casos en los cuales el intervalo entre el inicio de los síntomas y la toma de muestra fue mayor a 6 días, enfatiza la necesidad de la recolección temprana de especímenes. Las principales conclusiones de este estudio fueron la necesidad de establecer normas óptimas de higiene, informar rápidamente la ocurrencia de casos de gastroenteritis y confirmar la negativización de la excreción del patógeno.From October 15 to November 8, 2003, a gastrointestinal outbreak occurred at a day care center in a Hospital in Mar del Plata City. Fourteen out of 80 (17.5% children, mean age 23.6 ± 13.9 months, and the mother of one of them had diarrhea. One case developed hemolytic uremic syndrome. No conclusive evidence of the origin of the outbreak was found, but the epidemic curve suggested person-to-person spread. The usual practices at the place where infant milk formula was prepared at the day care center, together with the inadequate infrastructure conditions and hygiene practices at the kitchen of the hospital, were

Additional value of typing Noroviruses in gastroenteritis outbreaks in Amsterdam, The Netherlands.

Science.gov (United States)

Koek, A G; Bovée, L P M J; van den Hoek, J A R; Bos, A J; Bruisten, S M

2006-02-01

In Amsterdam, 17 of the 55 gastroenteritis (GI) outbreaks reported from January 2002 to May 2003 were confirmed to be caused by noroviruses (NV). In this study, we describe the molecular epidemiology of a group of nine outbreaks associated with a catering firm and two outbreaks, 5 months apart, in an Amsterdam hospital. All outbreaks were typed to confirm their linkage, and the hospital-related cases were studied to see if the two outbreaks were caused by one persisting NV strain or by a reintroduction after 5 months. For the outbreaks associated with the catering firm one NV genogroup I strain was found which was identical in sequence among customers and employees of the caterer. This was not the strain that predominantly circulated in 2002/2003 in and around Amsterdam, which was the NV genogroup II4 "new variant" (GgII4nv) strain. In the Amsterdam hospital, the two outbreaks were caused by this predominant GgII4nv type, and we argue that NV was most likely reintroduced in the second outbreak from the Amsterdam community.

Report of recombinant norovirus GII.g/GII.12 in Beijing, China.

Science.gov (United States)

Sang, Shaowei; Zhao, Zhongtang; Suo, Jijiang; Xing, Yubin; Jia, Ning; Gao, Yan; Xie, Lijun; Du, Mingmei; Liu, Bowei; Ren, Shiwang; Liu, Yunxi

2014-01-01

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. 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. 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 (ORF)1/ORF2 overlap. The GII.g ORF1/GII.12ORF2 recombinant has been reported in several countries and it was the first report of this recombinant in China.

Resistencia antimicrobiana en aislamientos clínicos de Klebsiella spp. y producción de B-lactamasas de espectro extendido en hospitales de Cuba

OpenAIRE

Quiñones Pérez, Dianelys; Carmona Cartaya, Yenisel; Zayas Illas, Arnaldo; Abreu Capote, Miriam; Salazar Rodriguez, Daniel; García Giro, Sandra; Torres Tamayo, Dalia; Kobayashi, Nobumichi; Valverde de Francisco, Aránzazu; del Campo Moreno, Rosa

2014-01-01

Introducción: el género Klebsiella causa brotes hospitalarios, por cepas multidrogorresistentes en diferentes continentes y conlleva a un aumento en la morbimortalidad. Objetivos: identificar las especies de Klebsiella causantes de infecciones en hospitales cubanos, determinar la procedencia de los aislamientos según el servicio, y la susceptibilidad antimicrobiana, conocer la prevalencia de aislamientos productores de ß-lactamasas de espectro extendido (BLEE), y tipos, así como la susceptibi...

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

La infección por virus Zika: una nueva emergencia de salud pública con gran impacto mediático

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Joan A. Caylà

2016-11-01

Full Text Available La infección por virus Zika (VZ está afectando intensamente a los países latinoamericanos y se ha convertido en una nueva epidemia mediática. Su posible asociación con microcefalia y síndrome de Guillain-Barré motivó que la Organización Mundial de la Salud (OMS declarase el 1 de febrero de 2016 que esta epidemia constituye una emergencia de salud pública de importancia internacional. Los datos epidemiológicos muestran una incidencia creciente en países como Brasil y Colombia, y que la epidemia sigue expandiéndose por muchos otros países. Desde enero de 2007 hasta el 27 de abril de 2016, la OMS ha detectado transmisión autóctona en 55 países (en 42 de ellos ha sido el primer brote de Zika, y 1198 microcefalias y otros trastornos neurológicos en Brasil. Así mismo, durante 2015 y 2016, 13 países detectaron un incremento de los casos de síndrome de Guillain-Barré y de confirmación de VZ asociado a este. En relación a las microcefalias y otras graves alteraciones cerebrales en recién nacidos de madres afectadas por VZ, las investigaciones ya evidencian una relación causal. Clínicamente muchos casos son asintomáticos y el diagnóstico ofrece dificultades con otras arbovirosis. El control de vectores en España es prioritario, dada la existencia de Aedes albopictus (mosquito tigre. También se recomienda el diagnóstico precoz, evitar viajes a zonas endémicas, mantener relaciones sexuales protegidas y procurar que la prioridad política, que puede evitar que esta epidemia se convierta en una enfermedad endémica de alta prevalencia, no nos haga olvidar otros problemas de salud.

Identification of QTLs Associated to Plant Architecture in Cassava (Manihot esculenta

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Camilo López

2016-01-01

Full Text Available La yuca (Manihot esculenta es el cuarto cultivo en importancia a nivel mundial como fuente de calorías para la población humana después del arroz, el azúcar y el maíz, posicionándose por esta razón como un cultivo primordial para la seguridad alimentaria. Su arquitectura ha sido considerada como un factor clave que subyace a la fisiología del rendimiento, relacionando características morfológicas con productividad. En este trabajo se evaluaron diferentes características de arquitectura vegetal en yuca. Los caracteres fueron evaluados en una población F1 compuesta por 133 hermanos completos (familia K sembrados en dos lugares biogeográficamente diferentes: La Vega (Cundinamarca y Arauca (Arauca en Colombia. Las características evaluadas relacionadas con la arquitectura vegetal fueron altura de la planta (AT, número de brotes (NB, longitud entrenudos (LE, número de raíces (NR, peso de raíces (PR, pigmentación del peciolo (PP, área de la hoja (AH y tipo de hoja (TH. A partir de los datos obtenidos y empleando un mapa genético de alta densidad basado en SNPs (Single Nucleotide Polymorphisms se llevó a cabo un análisis de QTLs (Quantitative Trait Loci. Se lograron identificar tres QTLs para La Vega asociados con los caracteres altura total, número de brotes y área de la hoja. Para Arauca se detectaron tres QTLs asociados con altura total, longitud de entrenudos y número de brotes. Los QTLs se distribuyeron en cuatro grupos de ligamiento y explicaron entre 18,93 y 41,92 % de la variación genética.

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. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Internalization of Sapovirus, a Surrogate for Norovirus, in Romaine Lettuce and the Effect of Lettuce Latex on Virus Infectivity

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Esseili, Malak A.; Zhang, Zhenwen

2012-01-01

Noroviruses are the leading cause of food-borne outbreaks, including those that involve lettuce. The culturable porcine sapovirus (SaV) was used as a norovirus surrogate to study the persistence and the potential transfer of the virus from roots to leaves and from outer to inner leaves of lettuce plants. Treatment of lettuce with SaV was done through the roots of young plants, the soil, or the outer leaves of mature plants. Sampling of roots, xylem sap, and inner and outer leaves followed by RNA extraction and SaV-specific real-time reverse transcription (RT)-PCR was performed at 2 h and on postinoculation days (PID) 2, 5, 7, 14, and/or 28. When SaV was inoculated through the roots, viral RNA persisted on the roots and in the leaves until PID 28. When the virus was inoculated through the soil, viral RNA was detected on the roots and in the xylem sap until PID 14; viral RNA was detected in the leaves only until PID 2. No infectious virus was detected inside the leaves for either treatment. When SaV was inoculated through the outer leaves, viral RNA persisted on the leaves until PID 14; however, the virus did not transfer to inner leaves. Infectious viral particles on leaves were detected only at 2 h postinoculation. The milky sap (latex) of leaves, but not the roots' xylem sap, significantly decreased virus infectivity when tested in vitro. Collectively, our results showed the transfer of SaV from roots to leaves through the xylem system and the capacity of the sap of lettuce leaves to decrease virus infectivity in leaves. PMID:22752176

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

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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

Lepidosaphes gloverii (Hemiptera: Diaspididae, Estudios Biológicos y Ecológicos en Cítricos de Cuba

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Caridad GONZÁLEZ

2005-01-01

Full Text Available Se estudió la distribución espacial y temporal de Lepidosaphes gloverii (Pack. y sus biorreguladores sobre naranjo Valencia en Cuba. Fueron examinados brotes orientados hacia los cuatro puntos cardinales y en tres estratos de los árboles. Los estados de desarrollo de L. gloverii y la incidencia de los biorreguladores se contabilizaron en el haz y el envés de las hojas. Se estudió la biología del insecto en plantines de lima Persa, limón Eureka y naranjo Valencia. Un complejo de enemigos naturales fue inventariado: parasitoides, depredadores y hongos entomopatógenos, los que difieren por su ubicación en micro hábitats. Se observó la tendencia de la población a la agregación, así como mayores densidades poblacionales hacia el noroeste del campo, el norte del árbol, la zona central del brote y el haz de las hojas.

The Prevalence of Norovirus in returning international travelers with diarrhea

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Löscher Thomas

2010-05-01

Full Text Available Abstract Background There is a high incidence of diarrhea in traveling populations. Norovirus (NV infection is a common cause of diarrhea and is associated with 7% of all diarrhea related deaths in the US. However, data on the overall prevalence of NV infection in traveling populations is limited. Furthermore, the prevalence of NV amongst travelers returning to Europe has not been reported. This study determined the prevalence of NV among international travelers returning to Germany from over 50 destinations in and outside Europe. Methods Stool samples of a total of 104 patients with a recent ( Results In our cohort, NV infection was detected in 15.7% of returning travelers with diarrhea. The closer to the date of return symptoms appeared, the higher the incidence of NV, ranging as high as 21.2% within the first four days after return. Conclusions In our cohort, NV infection was shown to be frequent among returning travelers especially in those with diarrhea, with over 1/5 of diarrhea patients tested positive for NV within the first four days after their return to Germany. Due to this prevalence, routine testing for NV infection and hygienic precautions may be warranted in this group. This is especially applicable to patients at an increased risk of spreading the disease, such as healthcare workers, teachers or food-handlers.

La interacción mente-movimiento en neurología y psiquiatría

OpenAIRE

William Fernández Escobar; Julio Manrique

1995-01-01

Los desórdenes del movimiento acompañan frecuentemente a enfermedades psiquiátricas como esquizofrenia, manía, depresión, ansiedad y trastornos obsesivo-cornpulsivos. Por otra parte, enfermedades extrapiramidales como la enfermedad de Parkinson y la enfermedad de Huntington se asocian con alteraciones neuropsiquiátricas tales como demencia, trastornos afectivos, brotes esquizofreniformes y conducta obsesivo-compulsiva. Esta interrelación sugiere que las manifestaciones motoras y mentales d...

Recognition of Histo-Blood Group Antigen-Like Carbohydrates in Lettuce by Human GII.4 Norovirus.

Science.gov (United States)

Gao, Xiang; Esseili, Malak A; Lu, Zhongyan; Saif, Linda J; Wang, Qiuhong

2016-05-15

Human norovirus (HuNoV) genogroup II genotype 4 (GII.4) strains account for about 80% of the gastroenteritis outbreaks in the United States. Contaminated food is a major transmission vehicle for this virus. In humans, pigs, and oysters, histo-blood group antigens (HBGAs) act as attachment factors for HuNoVs. In lettuce, although the virus-like particles (VLPs) of a GII.4 HuNoV were found to bind to cell wall carbohydrates, the exact binding site has not been investigated. Here, we show the presence of HBGA-like carbohydrates in the cell wall of lettuce. The digestion of lettuce leaves with cell wall-degrading enzymes exposed more binding sites and significantly increased the level of binding of GII.4 HuNoV VLPs. Competition assays showed that both the HBGA monoclonal antibody, recognizing the H type, and plant lectins, recognizing α-l-fucose in the H type, effectively inhibited VLP binding to lettuce tissues. Lettuce cell wall components were isolated and their NoV VLP binding characteristics were tested by enzyme-linked immunosorbent assays. The binding was inhibited by pretreatment of the lettuce cell wall materials with α-1,2-fucosidase. Collectively, our results indicate that H-type HBGA-like carbohydrates exist in lettuce tissues and that GII.4 HuNoV VLPs can bind the exposed fucose moiety, possibly in the hemicellulose component of the cell wall. Salad crops and fruits are increasingly recognized as vehicles for human norovirus (HuNoV) transmission. A recent study showed that HuNoVs specifically bind to the carbohydrates of the lettuce cell wall. Histo-blood group antigens (HBGAs) are carbohydrates and are known as the attachment factors for HuNoV infection in humans. In this study, we show the presence of HBGA-like carbohydrates in lettuce, to which HuNoVs specifically bind. These results suggest that specifically bound HuNoVs cannot be removed by simple washing, which may allow viral transmission to consumers. Our findings provide new information needed

Survival and transfer of murine norovirus 1, a surrogate for human noroviruses, during the production process of deep-frozen onions and spinach.

Science.gov (United States)

Baert, Leen; Uyttendaele, Mieke; Vermeersch, Mattias; Van Coillie, Els; Debevere, Johan

2008-08-01

The reduction of murine norovirus 1 (MNV-1) on onions and spinach by washing was investigated as was the risk of contamination during the washing procedure. To decontaminate wash water, the industrial sanitizer peracetic acid (PAA) was added to the water, and the survival of MNV-1 was determined. In contrast to onions, spinach undergoes a heat treatment before freezing. Therefore, the resistance of MNV-1 to blanching of spinach was examined. MNV-1 genomic copies were detected with a real-time reverse transcription PCR assay in PAA-treated water and blanched spinach, and PFUs (representing infectious MNV-1 units) were determined with a plaque assay. A onion bulbs and spinach leaves. More than 3 log PFU of MNV-1 was transmitted to onion bulbs and spinach leaves when these vegetables were washed in water containing approximately 5 log PFU/ml. No decline of MNV-1 occurred in used industrial spinach wash water after 6 days at room temperature. A concentration of 20 ppm of PAA in demineralized water (pH 4.13) and in potable water (pH 7.70) resulted in reductions of 2.88 +/- 0.25 and 2.41 +/- 0.18 log PFU, respectively, after 5 min of exposure, but no decrease in number of genomic copies was observed. No reduction of MNV-1 PFUs was observed on frozen onions or spinach during storage for 6 months. Blanching spinach (80 degrees C for 1 min) resulted in at least 2.44-log reductions of infectious MNV-1, but many genomic copies were still present.

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.

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.

Seroprevalencia del dengue en el distrito de Casma. Ancash, Perú 2002

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Jorge Gómez B

2005-07-01

Full Text Available Objetivos: Evaluar la magnitud de la infección por el virus del dengue después del primer brote presentado en el distrito de Casma, Ancash (febrero - abril 2002. Materiales y métodos: Se realizó un estudio seroepidemiológico postepidémico, se procesaron 400 muestras de sangre total recolectados en papel de filtro, las que fueron obtenidas por muestreo probabilístico, bietápico y de conglomerados en población del distrito de Casma. Se consideró como positivo a todo paciente con resultado positivo del ELISA de captura para IgM e IgG para dengue. Resultados: La prevalencia de infección en base a la encuesta seroepidemiológica encontrada fue de 14,1% (IC 95% 9,8 - 18,4%, por lo que se estima se presentaron 3939 (I.C.95% 2723- 5113 infecciones por el virus del dengue serotipo 1 en el distrito de Casma durante la epidemia de febrero a mayo del año 2002. El 60% de los casos positivos presentó sintomatología, el sistema de vigilancia epidemiológica notificó sólo 832 casos de dengue clásico, sin presentación de formas graves. Conclusiones: La seroprevalencia del primer brote de dengue en Casma en abril del año 2002 fue de 14,1%. El sistema de notificación obligatoria de la vigilancia epidemiológica detectó 21% del total estimado de personas infectadas (aproximadamente 1:5; y 35,2% de los casos que tuvieron sintomatología.

Factores y mecanismos relacionados con la dormancia en tubérculos de papa. Una revisión

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Rodriguez Luis Ernesto

2010-08-01

Full Text Available Los tubérculos de la papa (Solanum tuberosum L., al momento
de la cosecha y por un tiempo determinado, se encuentran en
estado dormante. La dormancia se induce con el inicio de la
tuberización y se define como un período en el cual no ocurre
ningún crecimiento visible de los brotes. Las hormonas vegetales
están involucradas en todas las fases de progresión de
la dormancia. Si bien el ácido abscísico (ABA y el etileno son
necesarios para su inducción, sólo el primero se requiere para
su mantenimiento. Los niveles de ABA se incrementan durante
la formación de los tubérculos, se mantienen constantes durante
la dormancia y disminuyen con el crecimiento activo de los
brotes. Un incremento en los niveles del ácido giberélico (AG
es necesario para inducir la formación del tubérculo, mientras
que una sensibilidad mayor a las citoquininas es determinante
para la pérdida de la dormancia. Cambios en los contenidos de
ácido indol acético (AIA y AG , están relacionados con la regulación
del crecimiento del brote una vez se rompe la dormancia.
Se ha comprobado que un factor importante, que contribuye
tanto a la inducción de la tuberización como a la pérdida de la
dormancia, es el flujo simplástico que controla la asignación de
azúcares, el cual se inicia con un meristemo apical dormante
aislado simplásticamente. La pérdida de dormancia se asocia
con la conexión simplástica del meristemo del brote con la red
de floema del tubérculo, y con una descarga simplástica en la
región de la yema, todo lo cual favorece el crecimiento activo
de los nuevos brotes.

Chikungunya, o la incapacidad del sistema general de seguridad social en salud para prevenir. Preguntas para reflexionar

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Lídice Alvarez-Miño

2015-04-01

Full Text Available De acuerdo con la Organización Mundial de la Salud (OMS, el virus del Chikungunya no es un evento nuevo. La fiebre Chikungunya es una enfermedad vírica transmitida al ser humano por mosquitos, la cual fue descrita por primera vez durante un brote ocurrido en el sur de Tanzanía en 19521 . Este país africano, ubicado en el trópico, tiene características similares, en lo ambiental y climático, a Colombia. Es decir, compartimos ambientes comunes en los cuales el mismo vector (Aedes Aegypti puede transmitir diferentes enfermedades, entre ellas el dengue.

Change in the terpenoid profile and secondary growth in declining stands of Pinus sylvestris L. under mediterranean influence as a response to local factors

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Sanz, M. A.

2014-12-01

Full Text Available The terpenoid profile could give information about the water status in Scots pine, especially for trees growing in the same geographical area but under contrasting local environmental conditions. Terpenes were analyzed by gas chromatography-mass spectrometry in needles, twigs and wood of ten affected and ten unaffected Scots pines in the southern “Sistema Ibérico” range (Teruel, Spain, where forest decline has been recently reported. Soil depth and secondary growth was also studied in both types of trees. Needles and twigs total resin acids were significantly higher in affected trees. The pimarane type resin acids were also higher in the twigs of affected trees. Secondary growth was lower in affected trees and it showed higher climate sensitivity. The use of the terpenoid profile may be used as an additional tool for the estimation of the water status, especially for situations inducing moderate but relatively prolonged stress conditions.El perfil terpénico podría dar información sobre el estado hídrico en el pino albar, especialmente cuando se comparen especímenes de una zona geográfica concreta afectados por factores ambientales locales. Los terpenos de acículas, brotes del año y madera fueron analizados en diez ejemplares afectados y otros tantos no afectados por el decaimiento mediante cromatografía de masas acoplada a espectrometría de masas. La serie de crecimiento secundario en ambos tipos de ejemplares fue también estudiada. La concentración total de ácidos resínicos aumentó de modo significativo en los árboles afectados tanto en brotes del año como en acículas. La cantidad de ácidos de tipo pimarano también aumentó en los brotes de los árboles afectados. La profundidad del suelo y el crecimiento secundario era menor en este tipo de ejemplares, que muestran una mayor sensibilidad en términos dendrocronológicos. El perfíl terpénico podría utilizarse como una herramienta adicional a la estimación del estado

Resultados y retos en salud pública ante la alerta por Ébola: una perspectiva desde Cataluña

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Mireia Jané

2017-03-01

Full Text Available El brote de enfermedad por virus Ébola iniciado en Guinea Conakry y notificado a la Organización Mundial de la Salud en marzo de 2014 ha sido el mayor documentado hasta la fecha. Su extensión a países limítrofes y el riesgo de expansión fuera del continente africano hicieron que, en agosto de 2014, fuese declarado emergencia de salud pública internacional. En el marco de lo establecido por el Centro de Coordinación de Alertas y Emergencias Sanitarias, la Agencia de Salud Pública de Cataluña inició las actuaciones de salud pública en marzo de 2014 y elaboró un único protocolo para todo el territorio, consejos para viajeros y cooperantes procedentes de países afectados, y una nota informativa semanal. Asimismo, en Cataluña, se crearon el Comité de Análisis y Seguimiento de Ébola y el Comité Científico Asesor de Ébola. Se realizaron sesiones informativas y formativas a más de 9600 profesionales de la salud de diferentes ámbitos. Desde agosto de 2014, a través del Sistema de Urgencias de Vigilancia Epidemiológica de Cataluña se notificaron 117 sospechas de Ébola. En tres casos se activó el protocolo con derivación al centro hospitalario de referencia, siendo los resultados descartados microbiológicamente. Se realizó la vigilancia de 95 cooperantes, un 52% mujeres y un 74% procedentes de Sierra Leona. En la gestión de alertas fueron esenciales la preparación y la planificación previas, el trabajo sinérgico entre la red epidemiológica, la asistencial y el conjunto de agentes implicados, así como la comunicación de riesgo precisa, veraz y proporcionada. Fue clave el circuito de cribado previo establecido ante la sospecha de casos por parte de los servicios de vigilancia epidemiológica. Así, solo se activó el protocolo de inmediato en aquellos casos que cumplían estrictamente los criterios. Este es un aspecto esencial a reforzar y mantener de cara a futuras alertas de salud pública internacional.

DISPONIBILIDAD DE LUZ Y PRODUCCIÓN DE NUEZ DESPUÉS DEL ACLAREO DE ÁRBOLES DE NOGAL PECANERO (Carya illinoensis

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J. G. Arreola Ávila

2010-01-01

Full Text Available El volumen de la copa bien iluminada es uno de los factores clave en la productividad de árboles de nogal pecanero. Cuando las huertas de nogal pecanero con densidades de plantación al menos de 100 árboles por hectárea presentan problemas de sombreo, la penetración de luz dentro de la copa del árbol y entre árboles, el crecimiento y la producción son negativamente afectadas. La investigación realizada para estudiar el efecto del aclareo de árboles de nogal pecanero sobre la disponibilidad de la luz y productividad de la huerta es limitada. El objetivo del presente estudio fue determinar el efecto del aclareo de árboles sobre la disponibilidad de radiación fotosintéticamente activa (RFA dentro de árboles permanentes, crecimiento del brote, producción y calidad de la nuez. Este estudio se llevó a cabo en una huerta madura de nogal pecanero con aclareo de árboles de 25 a 50 % durante el periodo 2004-2008. La disponibilidad de RFA dentro de árboles, longitud de brotes y la producción de nuez fueron afectadas por los tratamientos de aclareo; sin embargo, la calidad (porcentaje de almendra por árbol durante el periodo de tres años de estudio no fue significativamente afectada. Los resultados de este estudio indican que un gradual aclareo en huertas con problemas de sombreo debe realizarse para recuperar el crecimiento y componentes de producción.

Deciphering the Diversities of Astroviruses and Noroviruses in Wastewater Treatment Plant Effluents by a High-Throughput Sequencing Method.

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Prevost, B; Lucas, F S; Ambert-Balay, K; Pothier, P; Moulin, L; Wurtzer, S

2015-10-01

Although clinical epidemiology lists human enteric viruses to be among the primary causes of acute gastroenteritis in the human population, their circulation in the environment remains poorly investigated. These viruses are excreted by the human population into sewers and may be released into rivers through the effluents of wastewater treatment plants (WWTPs). In order to evaluate the viral diversity and loads in WWTP effluents of the Paris, France, urban area, which includes about 9 million inhabitants (approximately 15% of the French population), the seasonal occurrence of astroviruses and noroviruses in 100 WWTP effluent samples was investigated over 1 year. The coupling of these measurements with a high-throughput sequencing approach allowed the specific estimation of the diversity of human astroviruses (human astrovirus genotype 1 [HAstV-1], HAstV-2, HAstV-5, and HAstV-6), 7 genotypes of noroviruses (NoVs) of genogroup I (NoV GI.1 to NoV GI.6 and NoV GI.8), and 16 genotypes of NoVs of genogroup II (NoV GII.1 to NoV GII.7, NoV GII.9, NoV GII.12 to NoV GII.17, NoV GII.20, and NoV GII.21) in effluent samples. Comparison of the viral diversity in WWTP effluents to the viral diversity found by analysis of clinical data obtained throughout France underlined the consistency between the identified genotypes. However, some genotypes were locally present in effluents and were not found in the analysis of the clinical data. These findings could highlight an underestimation of the diversity of enteric viruses circulating in the human population. Consequently, analysis of WWTP effluents could allow the exploration of viral diversity not only in environmental waters but also in a human population linked to a sewerage network in order to better comprehend viral epidemiology and to forecast seasonal outbreaks. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

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

Exposure to bioaerosols can pose a health risk to workers at wastewater treatment plants (WWTPs) and to habitants of their surroundings. The main objective of this study was to examine the presence of harmful microorganisms in the air emission from a new type of hospital WWTP employing advanced...... 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 particle and endotoxin concentrations between locations. Bacterial concentrations were comparable or significantly lower in the exhaust air than inside the WWTP and in the upwind reference. Bacterial isolates were identified using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry...

MODELO MATEMÁTICO DEL TRANSPORTE DE UNA TOXINA EN UNA RED TRÓFICA MARINA

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Daniel Arbeláez A.

2014-07-01

Full Text Available Algunos casos de intoxicación por consumo de peces contaminados, como la intoxicación por ciguatera, ocurren inesperadamente y no son fáciles de detectar previamente, dado que los peces que portan la toxina no presentan aspecto y/o síntomas de enfermos. En este trabajo proponemos un modelo matemático para el transporte y acumulación de una toxina a través de una cadena alimentaria. El modelo se plantea mediante un sistema rígido de ecuaciones diferenciales que describen la dinámica. Se analiza la estabilidad local de la solución de equilibrio. Se discuten diferentes escenarios de aparición de brotes de una toxina a partir de simulaciones numéricas obtenidas mediante un esquema de discretización que combina un método de Runge-Kutta de tercer orden y la regla del trapecio, evitando la rigidez del sistema. Los resultados muestran que el tiempo que tarda en desaparecer la toxina en la red trófica depende del estado en que se encuentra la dinámica poblacional al momento del brote. Esta información puede emplearse para establecer un tiempo de veda en la pesca de tal manera que la toxina se reduzca a niveles inocuos para la salud humana.

Large multistate outbreak of norovirus gastroenteritis associated with frozen strawberries, Germany, 2012.

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Bernard, H; Faber, M; Wilking, H; Haller, S; Höhle, M; Schielke, A; Ducomble, T; Siffczyk, C; Merbecks, S S; Fricke, G; Hamouda, O; Stark, K; Werber, D

2014-02-27

From 20 September through 5 October 2012, the largest recorded food-borne outbreak in Germany occurred. Norovirus was identified as the causative agent. We conducted four analytical epidemiological studies, two case–control studies and two surveys (in total 150 cases) in secondary schools in three different federal states. Overall, 390 institutions in five federal states reported nearly 11,000 cases of gastroenteritis. They were predominantly schools and childcare facilities and were supplied almost exclusively by one large catering company. The analytical epidemiological studies consistently identified dishes containing strawberries as the most likely vehicle, with estimated odds ratios ranging from 2.6 to 45.4. The dishes had been prepared in different regional kitchens of the catering company and were served in the schools two days before the peaks of the respective outbreaks. All affected institutions had received strawberries of one lot, imported frozen from China. The outbreak vehicle was identified within a week, which led to a timely recall and prevented more than half of the lot from reaching the consumer. This outbreak exemplifies the risk of large outbreaks in the era of global food trade. It underlines the importance of timely surveillance and epidemiological outbreak investigations for food safety.

Inactivation of human norovirus surrogates by benzalkonium chloride, potassium peroxymonosulfate, tannic acid, and gallic acid.

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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.

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

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Alberto González Pedraza-Avilés

2002-09-01

Full Text Available 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 porcentajes de sensibilidad. La concentración inhibitoria mínima (CIM se obtuvo por microdilución semiautomatizada. Se utilizó un secuenciador automatizado de DNA para el análisis de variación de secuencias en los genes que codifican para proteína M y SpeA. Resultados. Todas las cepas fueron sensibles a beta-lactámicos y clindamicina; 12.7% fueron resistentes a eritromicina. El serotipo M2 fue el más frecuente, 27 del total. Prácticamente todas las bacterias (96% con el gen SpeA tienen el gen que codifica para el serotipo M2. Conclusiones. Debido a la reciente reaparición de infecciones por SGA se sugiere realizar estudios tanto de sensibilidad a macrólidos y beta-lactámicos, como de epidemiología molecular.Objective. To evaluate the in vitro activities of 13 antimicrobial agents against 47 group A Streptococcus pyogenes (GAS strains, and to determine the presence of genes encoding streptococcal pyrogenic exotoxin A (SpeA and the M--protein serotypes. Materials and Methods. A cross-sectional study was conducted at Centro de Salud Dr. José Castro Villagrana, during a scarlet fever outbreak occurring between December 1999 and January 2000, among 137 children at Colegio Espíritu de América. Minimum Inhibitory Concentrations (MICs were obtained by the semiautomated microdilution method. Automated DNA sequencing was used for analysis of sequence variation in genes encoding the M protein, and SpeA. Results. All strains were sensitive to

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

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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

Infectivity reduction efficacy of UV irradiation and peracetic acid-UV combined treatment on MS2 bacteriophage and murine norovirus in secondary wastewater effluent.

Science.gov (United States)

Weng, ShihChi; Dunkin, Nathan; Schwab, Kellogg J; McQuarrie, James; Bell, Kati; Jacangelo, Joseph G

2018-09-01

Peracetic acid (PAA) is a strong oxidant/bactericide that has been applied in various industries (e.g., food processing, pharmaceuticals, medical device sterilization, etc.) as a disinfectant. There is increasing interest in using PAA for wastewater disinfection because it does not form halogenated byproducts, and no post-treatment quenching is required. Previous studies have demonstrated good efficiency in controlling bacteria in wastewater, but limited information is available for viruses, especially those hosted by mammals (e.g., norovirus). Therefore, a study on the infectivity reduction of murine norovirus (MNV) was undertaken to evaluate the disinfection efficacy of PAA or UV alone and in combination with UV irradiation in undisinfected secondary effluent from a municipal wastewater reclamation facility (MWW) and phosphate buffer solution (PBS) at pH 7. Experiments employing MS2 bacteriophage were also performed in parallel for comparison purposes. MS2 infectivity reduction was found to be lower than MNV infectivity reduction for each condition studied - PAA, PAA + UV, and UV disinfection. These data suggest that MS2 may not be an appropriate surrogate to accurately predict the reduction of MNV infectivity. UV irradiation, in a dose range of 5-250 mJ/cm 2 , provided linear log inactivation (-log (N/N 0 )) with a regression slope (cm 2 mJ -1 ) of 0.031-0.034 and 0.165-0.202 for MS2 and MNV, respectively. UV irradiation provided similar inactivation for MS2 and MNV in both suspensions (PBS or MWW). Low infectivity reduction of MS2 was observed when PAA was used alone at a practical dose of 1.5 mg/L and below. A greater reduction of both MNV and MS2 was observed in PAA disinfection experiments using PBS as the microbial suspension medium, than in secondary effluent. Similar results were observed in PAA + UV experiments, in which greater synergistic effects were found in PBS than in MWW. Results of OH radical formation experiments suggest the presence of

Susceptibility of murine norovirus and hepatitis A virus to electron beam irradiation in oysters and quantifying the reduction in potential infection risks.

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Praveen, Chandni; Dancho, Brooke A; Kingsley, David H; Calci, Kevin R; Meade, Gloria K; Mena, Kristina D; Pillai, Suresh D

2013-06-01

Consumption of raw oysters is an exposure route for human norovirus (NoV) and hepatitis A virus (HAV). Therefore, efficient postharvest oyster treatment technology is needed to reduce public health risks. This study evaluated the inactivation of HAV and the NoV research surrogate, murine norovirus-1 (MNV-1), in oysters (Crassostrea virginica) by electron beam (E-beam) irradiation. The reduction of potential infection risks was quantified for E-beam irradiation technology employed on raw oysters at various virus contamination levels. The E-beam dose required to reduce the MNV and HAV titer by 90% (D(10) value) in whole oysters was 4.05 (standard deviations [SD], ±0.63) and 4.83 (SD, ±0.08) kGy, respectively. Microbial risk assessment suggests that if a typical serving of 12 raw oysters was contaminated with 10(5) PFU, a 5-kGy treatment would achieve a 12% reduction (from 4.49 out of 10 persons to 3.95 out of 10 persons) in NoV infection and a 16% reduction (from 9.21 out of 10 persons to 7.76 out of 10 persons) in HAV infections. If the serving size contained only 10(2) PFU of viruses, a 5-kGy treatment would achieve a 26% reduction (2.74 out of 10 persons to 2.03 out of 10 persons) of NoV and 91% reduction (2.1 out of 10 persons to 1.93 out of 100 persons) of HAV infection risks. This study shows that although E-beam processing cannot completely eliminate the risk of viral illness, infection risks can be reduced.

Medical Vanguard Diabetes Management Project

Science.gov (United States)

2005-10-01

Encefalitis Equina. Rev Panam Salud Publica , Jan. 1997, vol.1, no.1, p.78-83. ISSN 1020-4989. 8. CDC. Venezuelan Equine Encephalitis - Colombia, 1995. In...exhibition canceled due to equine encephalitis]. Panorama. 19 July 1995. 1—1. 42. PFIZER ADVERTISEMENT: La División de Salud Animal de Pfizer felicita...Carabobeño. 14 September 1995. C-5. 78. Por brote de encefalitis en el Zulia: Comisión de salud del congreso interpelará a ministros de sanidad y

Sunlight availability and nut production after thinning of pecan trees (Carya illinoensis K. Koch

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J. Arreola-Avila

2006-01-01

Full Text Available El volumen de la copa bien iluminada es uno de los principales factores en la productividad de árboles de árboles de nogal pecadero. Cuando las huertas adultas de nogal pecadero con altas densidades de plantación (al menos de 100 árboles por hectárea presentan entrecruzamiento, la penetración de radiación fotosintéticamente activa dentro de la copa del árbol y entre árboles, el crecimiento y la producción de nuez son negativamente afectadas. La investigación fue realizada para estudiar el efecto del aclareo de árboles de nogal pecadero sobre la disponibilidad de la luz y productividad de la huerta es limitada. El objetivo del presente experimento fue determinar el efecto del aclareo de árboles sobre la disponibilidad de radiación fotosintéticamente activa (RFA dentro y entre árboles permanentes, el crecimiento del brote, la densidad foliar, la producción y calidad de la nuez. Este estudio fue llevado a cabo en una huerta adulta de nogal pecadero con aclareo gradual de árboles de 25 a 50 %, durante el periodo 1995-1997. La disponibilidad de RFA dentro y entre árboles, la longitud de brotes, la densidad foliar y la producción por árbol fueron afectadas por los tratamientos de aclareo; sin embargo, la calidad de nuez (porcentaje de almendra por árbol durante el periodo de tres años de estudio, no fue afectada significativamente. Los resultados de este estudio indican que un gradual aclareo de la huerta debe realizarse en el momento apropiado de edad de la misma, para evitar una drástica reducción en la producción de nuez

Electron beam inactivation of Tulane virus on fresh produce, and mechanism of inactivation of human norovirus surrogates by electron beam irradiation.

Science.gov (United States)

Predmore, Ashley; Sanglay, Gabriel C; DiCaprio, Erin; Li, Jianrong; Uribe, R M; Lee, Ken

2015-04-02

Ionizing radiation, whether by electron beams or gamma rays, is a non-thermal processing technique used to improve the microbial safety and shelf-life of many different food products. This technology is highly effective against bacterial pathogens, but data on its effect against foodborne viruses is limited. A mechanism of viral inactivation has been proposed with gamma irradiation, but no published study discloses a mechanism for electron beam (e-beam). This study had three distinct goals: 1) evaluate the sensitivity of a human norovirus surrogate, Tulane virus (TV), to e-beam irradiation in foods, 2) compare the difference in sensitivity of TV and murine norovirus (MNV-1) to e-beam irradiation, and 3) determine the mechanism of inactivation of these two viruses by e-beam irradiation. TV was reduced from 7 log10 units to undetectable levels at target doses of 16 kGy or higher in two food matrices (strawberries and lettuce). MNV-1 was more resistant to e-beam treatment than TV. At target doses of 4 kGy, e-beam provided a 1.6 and 1.2 log reduction of MNV-1 in phosphate buffered saline (PBS) and Dulbecco's Modified Eagle Medium (DMEM), compared to a 1.5 and 1.8 log reduction of TV in PBS and Opti-MEM, respectively. Transmission electron microscopy revealed that increased e-beam doses negatively affected the structure of both viruses. Analysis of viral proteins by SDS-PAGE found that irradiation also degraded viral proteins. Using RT-PCR, irradiation was shown to degrade viral genomic RNA. This suggests that the mechanism of inactivation of e-beam was likely the same as gamma irradiation as the damage to viral constituents led to inactivation. Copyright © 2014 Elsevier B.V. All rights reserved.

Comportamiento de casos de Klebsiella pneumoniae productora de carbapenemasas en pacientes con cáncer de un hospital de tercer nivel de Bogotá, D.C.

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Sonia Isabel Cuervo

2014-04-01

Full Text Available Introducción. La presencia en los hospitales de enterobacterias productoras de carbapenemasas es cada vez más frecuente. Los pacientes con cáncer en estado avanzado requieren medios invasivos para el diagnóstico, el tratamiento o los cuidados paliativos, así como el uso de antimicrobianos de amplio espectro para tratar infecciones secundarias, lo cual aumenta su propensión a las infecciones causadas por estas bacterias. Objetivo. Informar el comportamiento de Klebsiella pneumoniae productora de carbapenemasas de tipo KPC en el Instituto Nacional de Cancerología de Bogotá, entre enero de 2010 y diciembre de 2012. Materiales y métodos. Mediante el análisis de la base de datos y de los registros de los pacientes con aislamientos de K. pneumoniae productores de carbapenemasas de tipo KPC, a cargo del comité de infecciones de la institución, se identificaron y describieron las características epidemiológicas de los casos detectados. La determinación de brotes se efectuó con herramientas de control estadístico de calidad. Resultados. Entre enero de 2010 y diciembre de 2012 se identificaron 45 pacientes con aislamiento de K. pneumoniae productor de carbapenemasas de tipo KPC en alguna muestra. Hubo más aislamientos en pacientes de cáncer con tumores sólidos. La identificación se logró más frecuentemente en muestras de orina; el 17,7 % de los casos correspondió a colonización y el 82,3 %, a infección; 35,5 % (16/45 de los pacientes sobrevivió. Durante este periodo se identificaron dos brotes que se controlaron aplicando una estrategia multimodal. Conclusiones. Se encontró que la presencia de KPC fue más frecuente en infecciones que en colonizaciones. Durante estos dos años ocurrieron dos brotes que fueron controlados limitando la transmisión cruzada de bacterias multirresistentes por medio de estrategias de control convencionales.

Epidemiological dynamics of norovirus GII.4 variant New Orleans 2009.

Science.gov (United States)

Medici, Maria Cristina; Tummolo, Fabio; De Grazia, Simona; Calderaro, Adriana; De Conto, Flora; Terio, Valentina; Chironna, Maria; Bonura, Floriana; Pucci, Marzia; Bányai, Kristián; Martella, Vito; Giammanco, Giovanni Maurizio

2015-09-01

Norovirus (NoV) is one of the major causes of diarrhoeal disease with epidemic, outbreak and sporadic patterns in humans of all ages worldwide. NoVs of genotype GII.4 cause nearly 80-90 % of all NoV infections in humans. Periodically, some GII.4 strains become predominant, generating major pandemic variants. Retrospective analysis of the GII.4 NoV strains detected in Italy between 2007 and 2013 indicated that the pandemic variant New Orleans 2009 emerged in Italy in the late 2009, became predominant in 2010-2011 and continued to circulate in a sporadic fashion until April 2013. Upon phylogenetic analysis based on the small diagnostic regions A and C, the late New Orleans 2009 NoVs circulating during 2011-2013 appeared to be genetically different from the early New Orleans 2009 strains that circulated in 2010. For a selection of strains, a 3.2 kb genome portion at the 3' end was sequenced. In the partial ORF1 and in the full-length ORF2 and ORF3, the 2011-2013 New Orleans NoVs comprised at least three distinct genetic subclusters. By comparison with sequences retrieved from the databases, these subclusters were also found to circulate globally, suggesting that the local circulation reflected repeated introductions of different strains, rather than local selection of novel viruses. Phylogenetic subclustering did not correlate with changes in residues located in predicted putative capsid epitopes, although several changes affected the P2 domain in epitopes A, C, D and E.

Norovirus-specific memory T cell responses in adult human donors

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Maria Malm

2016-10-01

Full Text Available Norovirus (NoV is a leading cause of acute gastroenteritis in people of all ages worldwide. NoV specific serum antibodies which block the binding of NoV virus-like particles (VLPs to the cell receptors have been thoroughly investigated. In contrast, only a few publications are available on the NoV capsid VP1 protein-specific T cell responses in humans naturally infected with the virus. Freshly isolated peripheral blood mononuclear cells of eight healthy adult human donors previously exposed to NoV were stimulated with purified VLPs derived from NoV GII.4-1999, GII.4-2012 (Sydney, and GI.3, and IFN-g production was measured by an ELISPOT assay. In addition, 76 overlapping synthetic peptides spanning the entire 539 amino acid sequence of GII.4 VP1 were pooled into two-dimensional matrices and used to identify putative T cell epitopes. Seven of the eight subjects produced IFN-g in response to the peptides and five subjects produced IFN-g in response to the VLPs of the same origin. In general, stronger T cell responses were induced with the peptides in each donor compared to the VLPs. A CD8+ T cell epitope in the shell domain of the VP1 (134SPSQVTMFPHIIVDVRQL151 was identified in two subjects, both having human leukocyte antigen (HLA-A*02:01 allele. To our knowledge, this is the first report using synthetic peptides to study NoV-specific T cell responses in human subjects and identify T cell epitopes.

Estrategia de PCR múltiple para la caracterización molecular simultánea de Staphylococcus aureus y enterotoxinas estafilocócicas en aislamientos de brotes de origen alimentario

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Aníbal A. Brizzio

2013-03-01

Full Text Available Introducción. La intoxicación alimentaria estafilocócica es la más frecuente de las intoxicaciones alimentarias. La acción de las enterotoxinas de Staphylococcus aureus en la luz intestinal provoca una importante pérdida de agua que origina vómitos y diarrea. Objetivo. Presentar una estrategia rápida, fiable y de bajo costo, basada en una reacción en cadena de la polimerasa (PCR múltiple para, simultáneamente, identificar S. aureus y detectar genes de las cinco enterotoxinas clásicas de S. aureus (sea, seb, sec, sed, see en cepas de Staphylococcus spp. aisladas de alimentos. Materiales y métodos. Se trabajó con aislamientos recuperados de 12 brotes de intoxicación alimentaria estafilocócica ocurridos en la provincia de Santa Fe, Argentina. El aislamiento y la caracterización fenotípica se llevaron a cabo mediante procedimientos estándar. La evaluación genotípica se hizo por una PCR múltiple, utilizando simultáneamente cebadores para los genes nuc, sea-see y 16S rRNA. Resultados. En las cepas analizadas se detectó 58 % de portadoras de genes toxigénicos. Las toxinas sea y seb se encontraron en igual porcentaje (29 %, mientras que las sec, sed y see se encontraron en menor e idéntica proporción (14 %. No encontramos más de un tipo diferente de enterotoxinas de S. aureus en los aislamientos analizados. Conclusiones. La estrategia de PCR múltiple diseñada en este trabajo permitió identificar cepas de S. aureus y confirmar, al mismo tiempo, su enterotoxigenicidad. En estos momentos, nuestros esfuerzos están dirigidos a detectar los genes que codifican enterotoxinas distintas de las clásicas, a fin de conocer su incidencia en las intoxicaciones alimentarias estafilocócicas e investigar su relevancia en la salud pública de nuestro país.   doi: http://dx.doi.org/10.7705/biomedica.v33i1.816

Norovirus infection: features of epidemiology and clinical and laboratory manifestations at the present stage

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N.V. Pronko

2017-02-01

Full Text Available Background. Among most significant for practical medicine infections, acute intestinal infections of viral etiology are becoming increasingly topical [2, 4]. According to domestic and foreign literature, up to 70 % of gastroenteritis occur during cold seasons of the year and are induced by viruses [3, 5]. The range of the factors producing viral diarrheas is rather wide. One of the comparatively new acute intestinal infections (AII producing factors is noroviruses [5, 6]. The prevalence of noroviruses has been little studied, and the clinical picture has been characterized insufficiently. This can be explained by insufficient diagnostics and registration of this infection [3, 6, 7]. Aim of the work: analysis of the morbidity and determination of clinical laboratory features of noroviral infection (NVI in children according to the data of the Regional Clinical Infectious Di­seases Hospital in Grodno. Materials and methods. A comprehensive clinical laboratory analysis of 1,105 case histories of children aged 1 month to 14 years with verified viral intestinal infection, who were admitted to Grodno Regional Clinical Infectious Diseases Hospital from January 2013 to December 2016, was carried out. The patients were divided according to the final clinical diagnosis in the following way: rotaviral infection (RVI was found in 676 (61.2 % individuals, adenoviral intestinal infection (AVI — in 212 (19.2 %, NVI was detected in 156 (14.1 % and enteroviral infection — in 61 (5.5 % persons. The examination was carried out according to the protocols approved by the Ministry of Health of the Republic of Belarus. Results. As our study showed, at the period analyzed the viral intestinal diseases amounted to 70.4 % of all the cases of diseases in the structure of AII in children. Patients hospitalized with viral diarrhea showed prevalence of RVI (61.2 %. NVI was the third by the incidence among viral diarrheas, and it was registered in 14.1 % of the cases

Survival and Transfer of Murine Norovirus within a Hydroponic System during Kale and Mustard Microgreen Harvesting

Science.gov (United States)

Wang, Qing

2015-01-01

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

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

2016-01-15

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

Predicción de la epidemia del virus sincitial respiratorio en Bogotá, D.C., utilizando variables climatológicas

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Gilberto González-Parra

2016-09-01

Full Text Available Introducción. El virus sincitial respiratorio es uno de los principales causantes de mortalidad de niños y adultos mayores en el mundo. Objetivo. Predecir las semanas de inicio de los brotes de infección por el virus sincitial respiratorio en Bogotá entre 2005 y 2010, utilizando variables climatológicas como variables de predicción. Materiales y métodos. Se establecieron las fechas de inicio de los brotes en niños menores de cinco años ocurridas entre 2005 y 2010, en Bogotá D.C., Colombia. Se seleccionaron las variables climatológicas utilizando una matriz de correlación y, posteriormente, se construyeron 1.020 modelos resultado de la combinación de las distintas variables climatológicas y las semanas de antelación al inicio del brote. Se seleccionaron los modelos utilizando los datos correspondientes a periodos de seis (2005-2010, cuatro (2005-2008 y dos años (2009-2010. Se determinaron los mejores modelos y las variables climatológicas más relevantes, utilizando clasificadores bayesanos ingenuos y curvas características de operación del receptor (Receiver Operating Characteristic, ROC. Resultados. Los mejores resultados se obtuvieron con los modelos que utilizaron el periodo de dos años (2009-2010 y la semana 0, con 52 y 60 % de aciertos, respectivamente. La humedad mínima fue la variable que más apareció en los mejores modelos (62 %. Los clasificadores bayesanos ingenuos permitieron establecer cuáles eran los mejores modelos para predecir la semana de inicio del brote. Conclusiones. Los resultados sugieren que los modelos en que se utilizaron la humedad mínima, la velocidad del viento y la temperatura mínima serían los modelos de predicción más eficaces.

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.

Mouse Norovirus infection promotes autophagy induction to facilitate replication but prevents final autophagosome maturation

International Nuclear Information System (INIS)

O’Donnell, Tanya B.; Hyde, Jennifer L.; Mintern, Justine D.; Mackenzie, Jason M.

2016-01-01

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.

Achyrocline satureioides (Lam.) DC. : propagación in vitro a partir de segmentos nodales

OpenAIRE

Gattusso, Susana; Scandizzi, Angel; Busilacchi, Héctor; Di Sapio, Osvaldo; Severin, Cecilia

2007-01-01

Achyrocline satureioides (Lam.) DC. conocida con el nombre vulgar de “marcela”, es intensamente utilizada en la medicina popular por sus propiedades medicinales. En el presente trabajo, se describe una técnica que permite la regeneración de plantas de A. satureioides mediante el cultivo in vitro de segmentos uninodales. Para la regeneración de brotes se empleó un medio semisólido conteniendo ¾ de la concentración de sales minerales y vitaminas del medio de cultivo de Murashige y Sko...

La legionelosis como enfermedad profesional: metodología de valoración

OpenAIRE

Dorronsoro Dorronsoro, Marta; Vicente Pardo, José Manuel

2014-01-01

La Legionella es una enfermedad bacteriana producida por la Legionella Pneumofila, patógeno oportunista que para causar una enfermedad debe estar presente en el lugar (reservorio), debe alcanzar un número suficiente para causar la infección (amplificación) y debe pasar al ambiente en estado infectivo (diseminación) los focos de contaminación que con mayor frecuencia han sido relacionados con los brotes epidémicos son instalaciones de suministro de agua y de acondicionamiento del aire de los e...

Evaluación de medios de cultivo in vitro para especies forestales nativas en peligro de extinción en ecuador

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Blanca Indacochea

2018-01-01

Full Text Available Las especies nativas Myroxylon balsamum (bálsamo, Tabebuia crhysantha (guayacán y Tabebuia billbergii (madero negro, son especies forestales endémicas del bosque seco de la costa del Ecuador y Perú. Los objetivos de la investigación fueron: i desarrollar un protocolo para establecer, multiplicar plantas micropropagadas en condiciones in vitro para el establecimiento de cultivos de especies nativas amenazadas en la zona sur de Manabí y ii definir los medios de cultivos y protocolos de desinfección más adecuados para la reproducción in vitro de las especies nativas amenazadas, empleando para el establecimiento diferentes concentraciones de Povidyn®, NaClO + Tween + HgCl2 y tiempos de exposición. De acuerdo con los resultados en la fase de establecimiento in vitro de explantes de M. balsamum, T. crhysantha y T. billbergii, se demostró que la aplicación de Povidyn® por 20 minutos + 15% NaClO + 2 gotas Tween por 5 minutos + 0,5% HgCl2 por 5 minutos, permitió reducir significativamente la contaminación de los explantes por microorganismos, alcanzando un 90%, 87% y 88% de explantes vivos respectivamente, libres de contaminación por hongos y bacterias a los 30 días de evaluación. En la fase de multiplicación in vitro, el medio MS suplementado con 2 mg.l-1 BAP + 1 mg.l-1 ANA, permitió generar el 80%, 82% y 87 de brotes sanos de M. balsamum, T. crhysantha y T. billbergii respectivamente. El enraizamiento de brotes de las 3 especies en dosis combinadas de BAP/AIB y BAP/ANA, no presentó efecto alguno. La producción in vitro de material vegetal seleccionado de M. balsamum, T. crhysantha y T. billbergii, confirma la utilidad de la micropropagación respecto del uso de técnicas convencionales.

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. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Emergence of a New Norovirus GII.4 Variant and Changes in the Historical Biennial Pattern of Norovirus Outbreak Activity in Alberta, Canada, from 2008 to 2013

Science.gov (United States)

Hasing, Maria E.; Preiksaitis, Jutta K.; Tellier, Raymond; Honish, Lance; Senthilselvan, Ambikaipakan; Pang, Xiaoli L.

2013-01-01

The public health impact of the emergence of new norovirus (NoV) strains is uncertain. A biennial pattern of alternating quiescent and epidemic levels of NoV outbreak activity associated with the emergence of new GII.4 variants was observed in Alberta, Canada, between July 2000 and June 2008. In this study, NoV genogroup I (GI) and GII strains isolated from 710 outbreak specimens in Alberta between July 2008 and January 2013 were characterized to update historical data. The seasonality and annual variation in NoV outbreak burden were analyzed over a 10-year period (July 2002 to June 2012). We found that GII.4-2006b had persisted as the predominant variant over three observation periods (July 2006 to June 2009) during which the biennial NoV outbreak pattern continued. The emergence of GII.4-2010 (winter 2009) was not associated with increased outbreak activity, and outbreak activity between July 2009 and June 2012 when GII.4-2010 predominated (67.5 to 97.7%) did not follow a biennial pattern. GII.4-2012 first emerged in Alberta in September 2011 and became predominant in observation period July 2012 to June 2013. NoV GI, relatively rare in past years, had a higher activity level (37.3%) as represented by GI.6 and GI.7 in the winter of 2012 to 2013. A higher proportion of GI outbreaks occurred in non-health care facility settings compared to GII. Our study suggests that factors other than new variants emergence contribute to the levels of NoV outbreak activity in Alberta. PMID:23637302

Binding of Human GII.4 Norovirus Virus-Like Particles to Carbohydrates of Romaine Lettuce Leaf Cell Wall Materials

Science.gov (United States)

Esseili, Malak A.

2012-01-01

Norovirus (NoV) genogroup II genotype 4 (GII.4) strains are the dominant cause of the majority of food-borne outbreaks, including those that involve leafy greens, such as lettuce. Since human NoVs use carbohydrates of histo-blood group antigens as receptors/coreceptors, we examined the role of carbohydrates in the attachment of NoV to lettuce leaves by using virus-like particles (VLPs) of a human NoV/GII.4 strain. Immunofluorescence analysis showed that the VLPs attached to the leaf surface, especially to cut edges, stomata, and along minor veins. Binding was quantified using enzyme-linked immunosorbent assay (ELISA) performed on cell wall materials (CWM) from innermost younger leaves and outermost lamina of older leaves. The binding to CWM of older leaves was significantly (P lettuce CWM by utilizing multiple carbohydrate moieties. This binding may enhance virus persistence on the leaf surface and prevent effective decontamination. PMID:22138991

Evaluation of the immunogenicity and protective effects of a trivalent chimeric norovirus P particle immunogen displaying influenza HA2 from subtypes H1, H3 and B

OpenAIRE

Gong, Xin; Yin, He; Shi, Yuhua; He, Xiaoqiu; Yu, Yongjiao; Guan, Shanshan; Kuai, Ziyu; Haji, Nasteha M; Haji, Nafisa M; Kong, Wei; Shan, Yaming

2016-01-01

The ectodomain of the influenza A virus (IAV) hemagglutinin (HA) stem is highly conserved across strains and has shown promise as a universal influenza vaccine in a mouse model. In this study, potential B-cell epitopes were found through sequence alignment and epitope prediction in a stem fragment, HA2:90-105, which is highly conserved among virus subtypes H1, H3 and B. A norovirus (NoV) P particle platform was used to express the HA2:90-105 sequences from subtypes H1, H3 and B in loops 1, 2 ...

Tifus Exantemático: enfermedad reemergente en el Perú

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Cecilia Morón C

1999-01-01

Full Text Available El tifus exantemático es producido por la Rickettsia prowazekii y transmitido por el piojo del cuerpo. Ocurre como brotes o epidemias que tienen la potencialidad de afectar a un gran número de personas en semanas a meses. El Perú notifica más del 50% de los casos de tifus exantemático a nivel mundial. El sistema de vigilancia es considerado incompleto debido básicamente a los limitados recursos económicos, la dificultad en las comunicaciones y la existencia de pocos laboratorios con experiencia en el diagnóstico de rickettsias. El diagnóstico laboratorial confirmatorio adecuado, y la búsqueda activa de casos, posiblemente con apoyo de la comunidad, pueden contribuir a fortalecerlo.

Contribuciones agroecológicas para renovar las fundaciones del manejo de plagas

OpenAIRE

Nicholls, Clara I.

2010-01-01

Las estrategias de manejo integrado de plagas (MIP) han estado dominadas por la idea del producto considerado como “la bala mágica’’ para controlar los brotes de plagas. Los enfoques del MIP no han abordado las causas ecológicas de los problemas de plagas en la agricultura moderna. En este articulo se plantea que los problemas de plagas pueden solucionarse mediante la reestructuración del manejo de los sistemas agrícolas, quebrando el monocultivo vía esquemas de diversificación...

Inmunidad de grupo. Significado e importancia

OpenAIRE

Vaqué Rafart, Josep

2005-01-01

En los últimos veinte años el concepto de “inmunidad de grupo” ha adquirido gran relevancia debido a su utilidad para definir los objetivos y estrategias de los programas de vacunación, pues permite determinar la intensidad de las actuaciones a aplicar para impedir brotes epidémicos y para controlar y eliminar enfermedades infecciosas. Su definición clásica, establecida por Fox en 1971, dice: "Es la resistencia de un grupo a una infección ante la que una amplia proporción de individuos posee ...

Anticuerpos policlonales contra la proteína recombinante NS3 del virus del dengue

OpenAIRE

Liliana Morales; Myriam L. Velandia; María Angélica Calderon; Jaime E. Castellanos; Jacqueline Chaparro-Olaya

2017-01-01

Introducción. El dengue es una enfermedad causada por uno de los cuatro serotipos del virus del dengue (DENV) y es endémica en, aproximadamente, 130 países. Su incidencia ha aumentado notablemente en las últimas décadas, así como la frecuencia y la magnitud de los brotes. A pesar de los esfuerzos, no existen tratamientos profilácticos ni terapéuticos contra la enfermedad y, en ese contexto, el estudio de los procesos que gobiernan el ciclo de infección del DENV es esencial para desarrollar...

Infección simultánea por el virus de la hepatitis E y de otras hepatitis virales en Colombia y su caracterización genotípica

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Dioselina Peláez

2016-08-01

Conclusiones. La mayor seropositividad se registró para las hepatitis A y E. La frecuencia de la infección simultánea con el virus de la hepatitis E y otros virus hepatótropos indica que este patógeno puede ser más frecuente de lo esperado. La circulación del genotipo 3a implica que esta enfermedad puede presentarse en forma de brote y de zoonosis en Colombia.

Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

International Nuclear Information System (INIS)

Nelson, O.D.; Keller, G.M.

1997-01-01

This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage

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. Copyright © 2013 Wiley Periodicals, Inc.

Fractional poisson--a simple dose-response model for human norovirus.

Science.gov (United States)

Messner, Michael J; Berger, Philip; Nappier, Sharon P

2014-10-01

This study utilizes old and new Norovirus (NoV) human challenge data to model the dose-response relationship for human NoV infection. The combined data set is used to update estimates from a previously published beta-Poisson dose-response model that includes parameters for virus aggregation and for a beta-distribution that describes variable susceptibility among hosts. The quality of the beta-Poisson model is examined and a simpler model is proposed. The new model (fractional Poisson) characterizes hosts as either perfectly susceptible or perfectly immune, requiring a single parameter (the fraction of perfectly susceptible hosts) in place of the two-parameter beta-distribution. A second parameter is included to account for virus aggregation in the same fashion as it is added to the beta-Poisson model. Infection probability is simply the product of the probability of nonzero exposure (at least one virus or aggregate is ingested) and the fraction of susceptible hosts. The model is computationally simple and appears to be well suited to the data from the NoV human challenge studies. The model's deviance is similar to that of the beta-Poisson, but with one parameter, rather than two. As a result, the Akaike information criterion favors the fractional Poisson over the beta-Poisson model. At low, environmentally relevant exposure levels (Poisson model; however, caution is advised because no subjects were challenged at such a low dose. New low-dose data would be of great value to further clarify the NoV dose-response relationship and to support improved risk assessment for environmentally relevant exposures. © 2014 Society for Risk Analysis Published 2014. This article is a U.S. Government work and is in the public domain for the U.S.A.

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

Directory of Open Access Journals (Sweden)

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

Cost-effectiveness of norovirus vaccination in children in Peru.

Science.gov (United States)

Mirelman, Andrew J; Ballard, Sarah Blythe; Saito, Mayuko; Kosek, Margaret N; Gilman, Robert H

2015-06-17

With candidate norovirus (NV) vaccines in a rapid phase of development, assessment of the potential economic value of vaccine implementation will be necessary to aid health officials in vaccine implementation decisions. To date, no evaluations have been performed to evaluate the benefit of adopting NV vaccines for use in the childhood immunization programs of low- and middle-income countries. We used a Markov decision model to evaluate the cost-effectiveness of adding a two-dose NV vaccine to Peru's routine childhood immunization schedule using two recent estimates of NV incidence, one for a peri-urban region and one for a jungle region of the country. Using the peri-urban NV incidence estimate, the annual cost of vaccination would be $13.0 million, offset by $2.6 million in treatment savings. Overall, this would result in 473 total DALYs averted; 526,245 diarrhea cases averted;153,735 outpatient visits averted; and 414 hospitalizations averted between birth and the fifth year of life. The incremental cost-effectiveness ratio would be $21,415 per DALY averted; $19.86 per diarrhea case; $68.23 per outpatient visit; and $26,298 per hospitalization. Using the higher jungle NV incidence rates provided a lower cost per DALY of $10,135. The incremental cost per DALY with per-urban NV incidence is greater than three times the 2012 GDP per capita of Peru but the estimate drops below this threshold using the incidence from the jungle setting. In addition to the impact of incidence, sensitivity analysis showed that vaccine price and efficacy play a strong role in determining the level of cost-effectiveness. The introduction of a NV vaccine would prevent many healthcare outcomes in the Peru and potentially be cost-effective in scenarios with high NV incidence. The vaccine cost-effectiveness model could also be applied to the evaluation of NV vaccine cost-effectiveness in other countries. In resource-poor settings, where NV incidence rates are expected to be higher. Published

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

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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

(Symphoricarpos microphyllus H.B.K.

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A. I. Quintero Sánchez

2008-01-01

Full Text Available El arbusto vara de perlilla (Symphoricarpos microphyllus H.B.K, es ampliamente utilizado para elaborar artesanías navideñas y para hacer escobas, pero la especie no se maneja, por lo que sus poblaciones naturales están siendo reducidas. En el presente trabajo se estudió su propagación vegetativa. Las estacas se colectaron en Nanacamilpa, Tlaxcala en abril de 2005. Se plantaron en una cama de crecimiento en el vivero forestal de la División de Ciencias Forestales de la Universidad Autónoma Chapingo, estableciéndose un diseño experimental en bloques completamente al azar, con cinco repeticiones. Los tratamientos fueron: aplicación de Radix® 10,000, de Raizone® plus y un testigo. Se estudió el prendimiento, longitud de brotes y biomasa. Para el análisis estadístico se empleó un procedimiento mixto. En las condiciones del estudio, se encontró que el mayor prendimiento fue de 77.6 y la mayor longitud de brotes 50.5 cm que se lograron con el uso de Radix® 10,000.

Enhanced severity of secondary dengue-2 infections: death rates in 1981 and 1997 Cuban outbreaks Aumento de la gravedad de las infecciones secundarias por dengue-2: tasas de mortalidad en los brotes cubanos de 1981 y 1997

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María G. Guzmán

2002-04-01

Full Text Available Objective. To understand the possible effect that length of time has on disease severity with sequential dengue infections. Methods. Death and hospitalization rates for dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS per 10 000 secondary dengue-2 infections were compared in the same age group for two dengue-2 (DEN-2 epidemics in Cuba. The first DEN-2 epidemic affected all of Cuba in 1981; the second one, in 1997, impacted only the city of Santiago de Cuba. The sensitizing infection for DHF/DSS for each of the DEN-2 epidemics was dengue-1 (DEN-1 serotype virus, which was transmitted in 1977-1979, that is, 4 years and 20 years before the two DEN-2 epidemics. Using published seroepidemiological data from the cities of Havana and Santiago de Cuba, we estimated the rates at which persons aged 15-39 years old and those 40 years and older were hospitalized or died of DHF/DSS in Havana and in all of Cuba in 1981 and in just Santiago de Cuba in 1997. Results. Among adults 15-39 years old the death rate per 10 000 secondary DEN-2 infections was 38.5 times as high in Santiago de Cuba in 1997 as in Havana in 1981. As a further indication of the increased severity coming with a longer period between the initial DEN-1 infection and the secondary DEN-2 infection, the case fatality rate for that same age group was 4.7 times as high in Santiago in 1997 as it was in Havana in 1981. Conclusion. We found a marked increase in severity with the longer of the two intervals (20 years between an initial DEN-1 infection and a secondary DEN-2 infection. Such a difference may be due to subtle shifts in causative dengue strains or to changes with the passage of time in the circulating population of human dengue antibodies. These observations have important implications for dengue control, pathogenic mechanisms, and vaccine development.Objetivos. Investigar el posible efecto del tiempo sobre la gravedad de la enfermedad en sucesivas infecciones por dengue. M�

A Waterborne Gastroenteritis Outbreak Caused by Norovirus GII.17 in a Hotel, Hebei, China, December 2014.

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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.

Norovirus outbreak caused by a new septic system in a dolomite aquifer

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Borchardt, M. A.; Bradbury, K.R.; Alexander, E.C.; Kolberg, R.J.; Alexander, S.C.; Archer, John R.; Braatz, L.A.; Forest, B.M.; Green, J.A.; Spencer, S. 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.

Ictiotoxismo por consumo de barracuda (Sphyraena barracuda y morena manchada (Gymnothorax moringa en la comunidad de pescadores artesanales de Tasajera, caribe colombiano

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Juan Diego Gaitán Espitia

2013-10-01

Full Text Available ResumenSe estudió un evento de ictiotoxismo en la comunidad de pescadores de la población de Tasajera, departamento del Magdalena. La intoxicación por ciguatera fue diagnosticada a 7 individuos cuyas edades oscilaban entre los 17 y 53 años (63,4% de rango de edades de los pescadores del sector, con síntomas de vómito (100%, dolor muscular en miembros inferiores (71,4%, espasmos abdominales (85,7%, diarrea (100%, entumecimiento y hormigueo de cara, manos, pies (85,7%, mareo (100%, y brote cutáneo (14,2%, los síntomas en la mayoría de los casos desaparecieron en un lapso de 8 a 12 días. Se determinó como causa principal del evento de ciguatera el consumo de carne de barracuda (Sphyraena barracuda y morena (Gymnothorax moringa. (Duazary 2007; 2: 160 - 167AbstractAn icthyotoxism event was studied in the Tasajera fishermen’s community, department of Magdalena. The ciguatera intoxication was diagnosed to 7 individuals whose ages were ranging between 17 and 53 years (63,4 %, with symptoms of vomit (100 %, muscular pain in low members (71,4 %, abdominal spasms (85,7 %, diarrhea (100 %, numbness and tingling of face, hands, feet (85,7 %, sickness (100 %, and cutaneous outbreak (14,2 %, the symptoms in the majority of the cases disappeared in a space from 8 to 12 days. The consumption of the barracuda (Sphyraena barracuda spotted moray (Gymnothorax moringa meat was determined as principal source of the ciguatera event.Key words: Icthyotoxism; Ciguatera; Intoxication; Colombian Caribbean.

Internalization and dissemination of human norovirus and Tulane virus in fresh produce is plant dependent.

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Yang, Zhihong; Chambers, Heather; DiCaprio, Erin; Gao, Gary; Li, Jianrong

2018-02-01

Human norovirus (NoV) is a leading cause of fresh produce associated outbreaks. Previous research indicates that the roots of growing leafy greens and berries internalize human NoV. However the effect of plant type and inoculum level on internalization rates has not been directly compared. In this study we compared the internalization and dissemination rates of human NoV and its surrogate, Tulane virus (TV) in green onion, radishes, and Romaine lettuce. We also evaluated the effect inoculum level and plant growth matrix on the rate of viral internalization. In the hydroponic growth system, we detected internalization and dissemination of human NoV RNA in green onions. In hydroponically growing green onions inoculated with high titer TV, we found higher rates of internalization and dissemination compared to green onions inoculated with low titer TV. In soil growth systems, no infectious TV was detected in either green onion or radishes. However, in Romaine lettuce plants grown in soil approximately 4 log 10  PFU/g was recovered from all tissues on day 14 p.i. Overall, we found that the type of plant, growth matrix, and the inoculum level influences the internalization and dissemination of human NoV and TV. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Efecto de la composición de una mezcla de hidrocarburos en la respuesta fenotípica y la acumulación de azúcares por Bouteloua curtipendula Michx. Torr. en cultivos in vitro

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Marianela Orozco-Soto

2015-07-01

Full Text Available Bouteloua curtipendulaMichx Torr. es un pasto originario de México con gran capacidad de adaptación a condiciones climáticas adversas, ha sido reportado con potencial para fitorremediar suelos contaminados con hidrocarburos (HC. En el presente estudio, se hicieron cultivos in vitro de B. curtipendula con una concentración de 1 500 mg HC·L-1 de medio de cultivo, y distintas mezclas de fenantreno (PHE, pireno (PYR y hexadecano (HXD. En todos los casos, tanto la longitud de brotes y raíces, así como la producción de biomasa disminuyeron signifi cativamente con respecto al control. El 100% de las semillas germinaron en el medio sin HC, mientras que en las mezclas con mayor proporción de HDX (1 100 mg HC·L-1 germinó alrededor del 75% de las semillas. La mayor acumulación de azúcares totales en el medio de cultivo, después de 35 días (40 mg de azúcares totales acumulados en el medio·mg-1 de raíz seca, equivalentes a 200 mg de azúcares totales·tubo se registró en la mezcla con menor concentración de HXD; por otro lado, en los cultivos donde no se adicionó HC se observó un consumo en los azúcares totales (225.7 ± 3 mg azúcares totales·tubo. Los resultados obtenidos sugieren que una mayor proporción de HXD en las mezclas incrementa el efecto tóxico a las plantas. Aunque hay estudios en donde se han cuantificado los azúcares exudados por las raíces, en nuestro conocimiento éste es el primer reporte de cultivos in vitro en donde se observa la producción de azúcares como respuesta de un pasto al estrés por HC.

El Laboratorio Clínico y el Dengue

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Gilberto Angel M.

1990-01-01

El dengue es una enfermedad endémica de zonas tropicales y subtropicales, en regiones que se encuentran por debajo de los 1.800 metros sobre el nivel del mar.

En 1969 se registraron varios brotes en el Caribe, Puerto Rico e Islas Vírgenes y en 1970 se diagnosticó en Barranquilla. En !975 se encontraron en el Magdalena medio unos 450 casos. En 1979 se señalaron unos 3.000 casos en México y en 1981 se padeció en Cuba una gran epidemia de dengue clásico tipo 1, que afe...

Complicaciones crónicas, hipertensión y obesidad en pacientes diabéticos en cartagena, colombia

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Alayón, Alicia N.; Altamar-López, Diana; Banquez-Buelvas, Clara

2009-01-01

Objetivos En marzo de 2008 ocurrió en el municipio de Santander de Quilichao-Cauca, Colombia, un brote de rabia de origen silvestre con 2 víctimas humanas. El presente artículo apunta a describir las técnicas diagnósticas de laboratorio, las acciones de investigación de campo y control de foco empleadas, y su significado epidemiológico e implicaciones en salud pública.Métodos La rabia se diagnosticó por inmunofluorescencia directa, prueba biológica en ratón, histopatología e inmunohistoquímic...

SENSIBILIDAD DE INMUNOIMPRESIÓN-ELISA Y DAS-ELISA EN EL DIAGNÓSTICO Y MUESTREO DEL VIRUS DE LA TRISTEZA DE LOS CÍTRICOS EN HUERTOS COMERCIALES DE TAMAULIPAS, MEXICO

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N. Ruiz-García

2009-01-01

Full Text Available El Virus de la tristeza de los cítricos (VTC causa una enfermedad de interés regulatorio para la citricultura mexicana. El diagnóstico y un muestreo oportuno y confiable es esencial para aplicar estrategias de manejo ante el avance en territorio nacional del pulgón café, su principal vector. Con el fin de contar con un método eficaz y eficiente para el muestreo y detección del VTC, se evaluó el desempeño del método de inmunoimpresión-ELISA con respecto a DAS-ELISA, el método oficial de diagnóstico, debido a su economía, facilidad y rapidez. Con este propósito se evaluaron 7,421 árboles, considerando la edad del brote y de infección, provenientes de 11 huertos comerciales de Tamaulipas. El método de inmunoimpresión-ELISA superó en sensibilidad y capacidad de pronóstico de positivos a DAS-ELISA en el diagnóstico de árboles con infección reciente o desconocida del VTC (P¿0.028. La disposición de brotes positivos en el dosel fue heterogénea siendo descrita por la función beta binomial (P¿0.16-0.23. Con base en esta función y la reproducción de los resultados de impresiones dobles por pecíolo (93.2 % se sugiere un tamaño óptimo de muestra de 10 pecíolos por árbol en impresiones simples. Este método fue 54.9 % más económico que DAS-ELISA y los diagnósticos se realizaron en una sexta parte del tiempo requerido en esta última prueba. Sin embargo, por el requerimiento de la norma oficial mexicana vigente (NOM- 031-FITO-2000, se recomienda el método de inmunoimpresión-ELISA como un método rápido para discriminar árboles positivos en muestreos de campo que deben posteriormente ser verificados por el método oficial de diagnóstico.

LOS ESTUDIOS EPIDEMIOLÓGICOS SOBRE LA POLIOMIELITIS EN ESPAÑA ANTES DE LA VACUNACIÓN

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J Ferran Martínez Navarro

2013-01-01

Full Text Available a erradicación de la poliomielitis en España es uno de los hitos sanitarios más importantes del siglo XX, no solo para la salud pública sino también por el efecto que su conocimiento científico tuvo en en el ámbito médico de nuestro país. El conocimiento de la literatura internacional por nuestros epidemiólogos y virólogos fue importante, como reflejan los estudios de los brotes epidémicos, los estudios virológicos y, lógicamente, los estudios clínicos. Para la salud pública representó, a lo largo de todo el siglo XX, un esfuerzo orientado a tomar decisiones basadas en el conocimiento científico. Para la epidemiología representó la aplicación de nuevas formas de trabajo y, por tanto, su modernización.

Delayed norovirus epidemic in the 2009-2010 season in Japan: potential relationship with intensive hand sanitizer use for pandemic influenza.

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Inaida, S; Shobugawa, Y; Matsuno, S; Saito, R; Suzuki, H

2016-09-01

Norovirus (NoV) epidemics normally peak in December in Japan; however, the peak in the 2009-2010 season was delayed until the fourth week of January 2010. We suspected intensive hand hygiene that was conducted for a previous pandemic influenza in 2009 as the cause of this delay. We analysed the NoV epidemic trend, based on national surveillance data, and its associations with monthly output data for hand hygiene products, including alcohol-based skin antiseptics and hand soap. The delayed peak in the NoV incidence in the 2009-2010 season had the lowest number of recorded cases of the five seasons studied (2006-2007 to 2010-2011). GII.4 was the most commonly occurring genotype. The monthly relative risk of NoV and monthly output of both alcohol-based skin antiseptics and hand soap were significantly and negatively correlated. Our findings suggest an association between hand hygiene using these products and prevention of NoV transmission.

A model for estimating pathogen variability in shellfish and predicting minimum depuration times.

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McMenemy, Paul; Kleczkowski, Adam; Lees, David N; Lowther, James; Taylor, Nick

2018-01-01

Norovirus is a major cause of viral gastroenteritis, with shellfish consumption being identified as one potential norovirus entry point into the human population. Minimising shellfish norovirus levels is therefore important for both the consumer's protection and the shellfish industry's reputation. One method used to reduce microbiological risks in shellfish is depuration; however, this process also presents additional costs to industry. Providing a mechanism to estimate norovirus levels during depuration would therefore be useful to stakeholders. This paper presents a mathematical model of the depuration process and its impact on norovirus levels found in shellfish. Two fundamental stages of norovirus depuration are considered: (i) the initial distribution of norovirus loads within a shellfish population and (ii) the way in which the initial norovirus loads evolve during depuration. Realistic assumptions are made about the dynamics of norovirus during depuration, and mathematical descriptions of both stages are derived and combined into a single model. Parameters to describe the depuration effect and norovirus load values are derived from existing norovirus data obtained from U.K. harvest sites. However, obtaining population estimates of norovirus variability is time-consuming and expensive; this model addresses the issue by assuming a 'worst case scenario' for variability of pathogens, which is independent of mean pathogen levels. The model is then used to predict minimum depuration times required to achieve norovirus levels which fall within possible risk management levels, as well as predictions of minimum depuration times for other water-borne pathogens found in shellfish. Times for Escherichia coli predicted by the model all fall within the minimum 42 hours required for class B harvest sites, whereas minimum depuration times for norovirus and FRNA+ bacteriophage are substantially longer. Thus this study provides relevant information and tools to assist

Effects of High-Hydrostatic Pressure on Inactivation of Human Norovirus and Physical and Sensory Characteristics of Oysters.

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Ye, Mu; Lingham, Talaysha; Huang, Yaoxin; Ozbay, Gulnihal; Ji, Lin; Karwe, Mukund; Chen, Haiqiang

2015-06-01

The purpose of the study was to determine the effect of high-hydrostatic pressure (HHP) on inactivation of human norovirus (HuNoV) in oysters and to evaluate organoleptic characteristics of oysters treated at pressure levels required for HuNoV inactivation. Genogroup I.1 (GI.1) or Genogroup II.4 (GII.4) HuNoV was inoculated into oysters and treated at 300 to 600 MPa at 25 and 0 °C for 2 min. After HHP, viral particles were extracted by porcine gastric mucin-conjugated magnetic beads (PGM-MBs) and viral RNA was quantified by real-time RT-PCR. Lower initial temperature (0 °C) significantly enhanced HHP inactivation of HuNoV compared to ambient temperature (25 °C; P oysters, respectively. HHP treatments did not significantly change color or texture of oyster tissue. A 1- to 5-scale hedonic sensory evaluation on appearance, aroma, color, and overall acceptability showed that pressure-treated oysters received significantly higher quality scores than the untreated control (P oysters. Oysters treated at 0 °C had slightly lower acceptability than the group treated at room temperature on day 1 (P 0.05). © 2015 Institute of Food Technologists®

PROPAGACIÓN VEGETATIVA DE PLÁTANO Y BANANO CON LA APLICACIÓN DE BENZILAMINOPURINA (6-BAP) Y ACIDO INDOLACETICO (AIA)

OpenAIRE

Hayron Fabricio Canchignia Martínez; Gonzalo Rafael Benavides Velasquez; Marjorie Dolores Espinoza Roca; Mercedes Susana Carranza Patiño; Orly Fernando Cevallos Falquez; Silvia Gicela Saucedo Aguiar

2008-01-01

En la propagación vegetativa de dos variedades de Banano (Valery y Orito) y una de Plátano (Barraganete), se sometió a diferentes tratamientos hormonales, para evaluar el número de brotes, la concentración 30 mg L-1 de BAP alcanzó el mayor promedio, con 2.36 brotes para todas las variedades. En longitud y diámetro de brotes, la concentración que logró el mayor promedio fue C0, no encontrándose diferencias entre las concentraciones de 6-BAP y AIA. La variedad que presentó la mayor longitud y d...

Situación epidemiológica y de los factores de riesgo de transmisión de Leishmania infantum en España

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Berta Suárez Rodríguez

2012-01-01

Full Text Available En España la leishmaniasis es una zoonosis endémica presente en la mayor parte del territorio peninsular e Islas Baleares. El parásito que se detecta es la Leishmania infantum y el principal reservorio es el perro. Los vectores competentes para transmitir el parásito son los flebotomos, de los que existen dos especies distribuidas por todo el territorio peninsular e Islas Baleares. En este artículo se revisa la situación actual y el comportamiento de la leishmaniasis en España. Se analiza y compara la información sobre la enfermedad procedente de las altas hospitalarias y de la Red Nacional de Vigilancia Epidemiológica así como los factores de riesgo identificados en estudios anteriores que facilitan la transmisión. Desde 2009 está teniendo lugar un brote en el suroeste de la Comunidad de Madrid, destacando el elevado número de casos, cerca de 400 y la detección de un nuevo reservorio, la liebre. Las condiciones que pueden incrementar la incidencia de la leishmaniasis están asociadas al aumento del número de vectores infectados, al de la densidad del flebotomo, al de hospedadores o la aparición de nuevos reservorios en un área geográfica. Esta infección tiene una dinámica de transmisión compleja y para responder oportunamente a los brotes debe estar previamente desarrollado un plan de acción integral y multisectorial en el que participen todas las instituciones involucradas. Ante un brote, es importante estudiar los factores que condicionan la transmisión del lugar y adaptar el plan de acción a sus características específicas.

Seasonal distribution and evolving forms of multiple sclerosis patients diagnosed from April 2004 to November 2007 Distribución estacional y formas evolutivas de esclerosis múltiple en pacientes diagnosticados entre Abril del 2004 y Noviembre del 2007

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Hermes Fundora-Hernández

2009-09-01

Full Text Available BACKGROUND: Multiple sclerosis (MS was first reported in Cuba in 1965. The most frequent appearance is observed in the first six months of the year. OBJECTIVE: To determine the seasonal distribution and evolving forms of MS patients diagnosed with the disease between April 2004 and November 2007. METHOD: Twenty-one patients with suspected MS and 42 outbreaks were studied. Patients were classified according to Lublin and Revingold's criteria for clinical forms and according to McDonald. RESULTS: Most patients were classified in outbreak and remission and only two patients classified as primary-progressive multiple sclerosis. The higher number of outbreaks occurred in the first two quarters of the year. CONCLUSION: It is recommended to study further weather variables that may be related to the emergence of these outbreaks in our environment.INTRODUCCIÓN: La esclerosis múltiple (EM fue reportada en Cuba por primera vez en 1965. Se ha venido observando la aparición más frecuente en los primeros seis meses del año. OBJETIVO: Determinar la distribución estacional y formas evolutivas de EM en pacientes con diagnóstico de esta enfermedad entre abril 2004 y noviembre 2007. MÉTODO: Se estudiaron 21 pacientes con sospecha de EM y un total de 42 brotes. Los pacientes fueron clasificados según los criterios de Lublin y Revingold para las formas evolutivas y según los criterios de McDonald. RESULTADOS: Solo dos pacientes clasificaron en la forma evolutiva progresiva primaria; los primeros dos trimestres del año fueron los de mayor número de brotes. CONCLUSIÓN: Se recomienda profundizar en las variables climatológicas que pudieran tener vínculo con la aparición de estos brotes en nuestro medio.

Portable exhauster POR-007/Skid E and POR-008/Skid F storage plan

International Nuclear Information System (INIS)

Nelson, O.D.

1998-01-01

This document provides storage requirements for 1,000 CFM portable exhausters POR-O07/Skid E and POR-008/Skid F. These requirements are presented in three parts: preparation for storage, storage maintenance and testing, and retrieval from storage. The exhauster component identification numbers listed in this document contain the prefix POR-007 or POR-008 depending on which exhauster is being used

Community-Acquired Rotavirus Gastroenteritis Compared with Adenovirus and Norovirus Gastroenteritis in Italian Children: A Pedianet Study

Directory of Open Access Journals (Sweden)

D. Donà

2016-01-01

Full Text Available Background. Rotavirus (RV is the commonest pathogen in the hospital and primary care settings, followed by Adenovirus (AV and Norovirus (NV. Only few studies that assess the burden of RV gastroenteritis at the community level have been carried out. Objectives. To estimate incidence, disease characteristics, seasonal distribution, and working days lost by parents of RV, AV, and NV gastroenteritis leading to a family pediatrician (FP visit among children < 5 years. Methods. 12-month, observational, prospective, FP-based study has been carried out using Pedianet database. Results. RVGE incidence was 1.04 per 100 person-years with the highest incidence in the first 2 years of life. Incidences of AVGEs (1.74 and NVGEs (1.51 were slightly higher with similar characteristics regarding age distribution and symptoms. Risk of hospitalisation, access to emergency room (ER, and workdays lost from parents were not significantly different in RVGEs compared to the other viral infections. Conclusions. Features of RVGE in terms of hospitalisation length and indirect cost are lower than those reported in previous studies. Results of the present study reflect the large variability of data present in the literature. This observation underlines the utility of primary care networks for AGE surveillance and further studies on community-acquired gastroenteritis in children.