Characterization of a monoclonal antibody against the hemagglutinin stem of H7N9 subtype avian influenza virus / 生物工程学报

The conserved hemagglutinin (HA) stem region of avian influenza virus (AIV) is an important target for designing broad-spectrum vaccines, therapeutic antibodies and diagnostic reagents. Previously, we obtained a monoclonal antibody (mAb) (5D3-1B5) which was reactive with the HA stem epitope (aa 428-452) of H7N9 subtype AIV. To systematically characterize the mAb, we determined the antibody titers, including the HA-binding IgG, hemagglutination-inhibition (HI) and virus neutralizing (VN) titers. In addition, the antigenic epitope recognized by the antibody as well as the sequence and structure of the antibody variable region (VR) were also determined. Moreover, we evaluated the cross-reactivity of the antibody with influenza virus strains of different subtypes. The results showed that the 5D3-1B5 antibody had undetectable HI and VN activities against H7N9 virus, whereas it exhibited strong reactivity with the HA protein. Using the peptide-based enzyme-linked immunosorbent assay and biopanning with a phage-displayed random peptide library, a motif with the core sequence (431W-433Y-437L) in the C-helix domain in the HA stem was identified as the epitope recognized by 5D3-1B5. Moreover, the mAb failed to react with the mutant H7N9 virus which contains mutations in the epitope. The VR of the antibody was sequenced and the complementarity determining regions in the VR of the light and heavy chains were determined. Structural modeling and molecular docking analysis of the VR verified specific binding between the antibody and the C-helix domain of the HA stem. Notably, 5D3-1B5 showed a broad cross-reactivity with influenza virus strains of different subtypes belonging to groups 1 and 2. In conclusion, 5D3-1B5 antibody is a promising candidate in terms of the development of broad-spectrum virus diagnostic reagents and therapeutic antibodies. Our findings also provided new information for understanding the epitope characteristics of the HA protein of H7N9 subtype AIV.

A broadly neutralizing human monoclonal antibody against the hemagglutinin of avian influenza virus H7N9 / 中华医学杂志(英文版)

BACKGROUND@#The new emerging avian influenza A H7N9 virus, causing severe human infection with a mortality rate of around 41%. This study aims to provide a novel treatment option for the prevention and control of H7N9.@*METHODS@#H7 hemagglutinin (HA)-specific B cells were isolated from peripheral blood plasma cells of the patients previously infected by H7N9 in Jiangsu Province, China. The human monoclonal antibodies (mAbs) were generated by amplification and cloning of these HA-specific B cells. First, all human mAbs were screened for binding activity by enzyme-linked immunosorbent assay. Then, those mAbs, exhibiting potent affinity to recognize H7 HAs were further evaluated by hemagglutination-inhibiting (HAI) and microneutralization in vitro assays. Finally, the lead mAb candidate was selected and tested against the lethal challenge of the H7N9 virus using murine models.@*RESULTS@#The mAb 6-137 was able to recognize a panel of H7 HAs with high affinity but not HA of other subtypes, including H1N1 and H3N2. The mAb 6-137 can efficiently inhibit the HA activity in the inactivated H7N9 virus and neutralize 100 tissue culture infectious dose 50 (TCID50) of H7N9 virus (influenza A/Nanjing/1/2013) in vitro, with neutralizing activity as low as 78 ng/mL. In addition, the mAb 6-137 protected the mice against the lethal challenge of H7N9 prophylactically and therapeutically.@*CONCLUSION@#The mAb 6-137 could be an effective antibody as a prophylactic or therapeutic biological treatment for the H7N9 exposure or infection.

Questions and answers / Preguntas y respuestas

In which country did the first epidemic caused by the avian flu virus, known as severe acute respiratory syndrome (SARS) emerged.

¿En qué país surgió la primera epidemia causada por el virus de la gripe aviar, conocida como síndrome respiratorio agudo severo (SARS)

Avian influenza A (H7N9) virus: from low pathogenic to highly pathogenic / 医学前沿

The avian influenza A (H7N9) virus is a zoonotic virus that is closely associated with live poultry markets. It has caused infections in humans in China since 2013. Five waves of the H7N9 influenza epidemic occurred in China between March 2013 and September 2017. H7N9 with low-pathogenicity dominated in the first four waves, whereas highly pathogenic H7N9 influenza emerged in poultry and spread to humans during the fifth wave, causing wide concern. Specialists and officials from China and other countries responded quickly, controlled the epidemic well thus far, and characterized the virus by using new technologies and surveillance tools that were made possible by their preparedness efforts. Here, we review the characteristics of the H7N9 viruses that were identified while controlling the spread of the disease. It was summarized and discussed from the perspectives of molecular epidemiology, clinical features, virulence and pathogenesis, receptor binding, T-cell responses, monoclonal antibody development, vaccine development, and disease burden. These data provide tools for minimizing the future threat of H7N9 and other emerging and re-emerging viruses, such as SARS-CoV-2.

Molecular diagnosis of avian viruses in grassland passerines and captive yellow cardinals Gubernatrix cristata in Brazil / Diagnóstico molecular de vírus aviários em passeriformes campestres e cardeais-amarelos Gubernatrix cristata cativos no Brasil

Avian influenza viruses (AIVs), Newcastle disease virus (NDV), West Nile virus (WNV), adenovirus (AV) and herpesvirus (HV) play an important role in the health of human and animal populations. However, knowledge of the prevalence of these viruses in wild birds is restricted to some groups (e.g. shorebirds) or regions worldwide. Information on grassland birds of South America, which is essential for their conservation, is scarce. The objectives of the present study were to evaluate occurrences of AIV, NDV, WNV, AV and HV for the first time in a bird community of a unique protected area in southern Brazil, which is home for the critically endangered yellow cardinal (Gubernatrix cristata), and captive yellow cardinals from fauna maintainers of the Brazilian Captive Program of the Yellow Cardinal. Passerine species of wild life were caught, identified and samples (swabs) were collected from the oropharynx and cloaca of 64 passerines of 26 species (including 3 yellow cardinals) and 30 yellow cardinals of captive, for molecular diagnosis. The samples were subjected to RNA and DNA extraction and the real-time polymerase chain reaction (RT-PCR) for AIV, NDV and WNV and nested PCR for AV and HV. One yellow cardinal of captive presented a positive result for AV, this result is important for planning, managing natural attributes and making decisions in relation to integrated conservation of threatened species. This is the first report of AV in yellow cardinal and epidemiological investigation of viruses in wild passerines of the Pampa biome, in Rio Grande do Sul, Brazil.(AU)

Os vírus da gripe aviária (VGA), vírus da doença de Newcastle (VDN), vírus do Nilo Ocidental (VNO), adenovírus (AV) e herpesvírus (HV) desempenham um papel importante na saúde das populações humana e animal. No entanto, o conhecimento da prevalência desses vírus em aves selvagens é restrito a alguns grupos (por exemplo, aves limícolas) ou regiões em todo o mundo. As informações sobre as aves campestres da América do Sul, essenciais para a sua conservação, são escassas. Os objetivos do presente estudo foram avaliar a ocorrência de VGA, VDN, VNO, AV e HV pela primeira vez em uma comunidade de aves de uma área única protegida no Sul do Brasil, que abriga o cardeal-amarelo (Gubernatrix cristata) criticamente ameaçado de extinção e em cardeais-amarelos de cativeiro dos mantenedores de fauna do Programa Brasileiro de Cativeiro do Cardeal-amarelo. Espécies de passeriformes silvestres foram capturadas, identificadas e amostras (swabs) foram coletadas da orofaringe e cloaca de 64 passeriformes de 26 espécies (incluindo 3 cardeais-amarelos) e 30 cardeais-amarelos de cativeiro, para diagnóstico molecular. As amostras foram submetidas à extração de RNA e DNA e à reação em cadeia da polimerase em tempo real (RT-PCR) para VGA, VDN e VNO e nested PCR para AV e HV. Um cardeal-amarelo de cativeiro apresentou resultado positivo para AV, este resultado é importante para o planejamento, manejo dos atributos naturais e tomada de decisões em relação à conservação integrada de espécies ameaçadas. Este é o primeiro relato de AV em cardeal-amarelo e de investigação epidemiológica de vírus em passeriformes silvestres do bioma Pampa, no Rio Grande do Sul, Brasil.(AU)

Influenza A/H1N1 e COVID-19 no Brasil: impactos e diferenças epidemiológicas / Influenza A/H1N1 and COVID-19 in Brazil: epidemiological impacts and diferences / Influenza A/H1N1 y COVID-19 en Brasil: impactos epidemiológicos y diferencias

Justificativa e Objetivos: Em 2009, o Brasil enfrentou a pandemia de influenza A/H1N1pdm09 que infectou, pelo menos, 50 mil pessoas. Em 2020, enfrenta outra pandemia causada pelo vírus SARS-Cov-2 (COVID-19). Por se tratar de uma doença nova, há muita especulação sobre a mesma, assim como comparação com outros cenários, muitas vezes com base em informações falsas. Este estudo compara os impactos e diferenças epidemiológicas da Influenza A/H1N1 e COVID-19 no Brasil. Métodos: Estudo quantitativo, descritivo, epidemiológico, de base documental, cujos dados foram coletados nas plataformas de informação do Ministério da Saúde do Brasil e da Organização Mundial da Saúde, além de artigos científicos. Os dados sobre Influenza A/H1N1 referem-se ao ano de 2009 e os de COVID-19 ao período de março a 30 de abril de 2020. Resultados: Constata-se que no Brasil, em apenas dois meses, o número de casos da COVID-19 (85.380) já ultrapassou o total de casos de influenza A/H1N1pdm09 (50.482) ocorridos em todo o ano de 2009 e provocou o triplo de óbitos. Portanto, a COVID-19 apresenta-se de forma mais severa, dada as proporções alcançadas em letalidade, pela falta de vacina e tratamento específico dos casos. Conclusão: A pandemia da COVID-19 é mais impactante para o Brasil que a pandemia da influenza A/H1N1pdm09.(AU)

Background and Objectives: In 2009, Brazil faced the influenza A/H1N1pdm09 pandemic that infected at least 50 thousand people. In 2020, it faces another pandemic caused by the SARS-Cov-2 virus (COVID-19). Because it is a new disease, there is much speculation about it and comparison with other scenarios, often based on fake news. This study compares the impacts and epidemiological differences of Influenza A / H1N1 and COVID-19 in Brazil. Methods: Quantitative, descriptive, epidemiological study, based on documents, whose data were collected on the information platforms of the Ministry of Health of Brazil and the World Health Organization, in addition to scientific articles. The data on Influenza A/H1N1 refer to the year 2009 and the data on COVID-19 to the period from March to April 30, 2020. Results: It appears that in Brazil, in just two months the number of cases of COVID-19 (85,380) has already exceeded the total cases of influenza A/H1N1pdm09 (50,482) that occurred in the whole year of 2009 and caused a triple of deaths. Therefore, COVID-19 presents itself more severely, given the proportions reached in lethality, due to the lack of vaccine and specific treatment of cases. Conclusion: The COVID-19 pandemic is more impactful for Brazil than the influenza A/H1N1pdm09 pandemic.(AU)

Justificación y Objetivos: En 2009, Brasil se enfrentó a la pandemia de influenza A / H1N1pdm09 que infectó al menos a 50,000 personas. En 2020, se enfrenta a otra pandemia causada por el virus SARS-Cov-2 (COVID-19). Como se trata de una enfermedad nueva, se especula mucho y se compara con otros escenarios, a menudo basados en información falsa. Este estudio compara los impactos y las diferencias epidemiológicas de la Influenza A / H1N1 y COVID-19 en Brasil. Métodos: Estudio epidemiológico cuantitativo, descriptivo, basado en documentos, cuyos datos fueron recolectados en las plataformas de información del Ministerio de Salud de Brasil y de la Organización Mundial de la Salud, además de artículos científicos. Los datos sobre Influenza A / H1N1 se refieren al año 2009 y los datos sobre COVID-19 al período de marzo al 30 de abril de 2020. Resultados: Parece que en Brasil, en solo dos meses, el número de casos de COVID-19 (85,380) ya excedió el número total de casos de influenza A / H1N1pdm09 (50,482) que ocurrieron en todo el año de 2009 y causaron un triple de muertes. Por lo tanto, COVID-19 se presenta más severamente, dadas las proporciones alcanzadas en la letalidad, debido a la falta de vacuna y al tratamiento específico de los casos. Conclusión: La pandemia de COVID-19 es más impactante para Brasil que la pandemia de influenza A / H1N1pdm09.(AU)

Una revisión sistemática de los patógenos virales y bacterianos de aves silvestres en Chile / A systematic revision of viral and bacterial pathogens of free-ranging wild birds in Chile

Resumen El conocimiento acerca de agentes patógenos presentes en aves silvestres es crucial para la apropiada prevención de eventos de transmisión que puedan afectar a la salud pública y animal. Esta revisión sistemática organiza toda la información disponible acerca de los patógenos virales y bacterianos de las aves silvestres chilenas, determina qué patógenos y órdenes de aves han recibido atención reciente por parte de la comunidad científica local, evalúa cambios en la frecuencia de publicación de artículos e identifica brechas en el conocimiento respecto a estos patógenos. Un total de 35 artículos revisados por pares han sido publicados desde enero de 1941 hasta abril de 2019. Agentes virales fueron evaluados en 11 estudios, mientras que 24 concernieron a bacterias. Los artículos científicos se han publicado mayormente de forma discontinua en años previos al 2006. Salmonella spp. e influenza aviar han sido los patógenos más estudiados con 10 y 8 estudios, respectivamente. Las regiones de Los Ríos y Valparaíso concentran el mayor número de estudios y no se ha realizado investigación en las regiones de O'Higgins, Maule y Aysén. En general, la información acerca de patógenos en aves silvestres es escasa, por lo que es necesario incrementar los esfuerzos para identificar patógenos portados por reservorios aviares y evaluar el riesgo potencial que pueden representar para la conservación de fauna silvestre, producción animal y el sistema de salud pública en Chile.

Abstract Knowledge about pathogenic agents present in wild birds is pivotal to properly prevent transmission events that might threaten public and animal health. This systematic review organizes all information available about viral and bacterial pathogens of Chilean wild birds, determines which pathogens and avian orders have received attention from the local scientific community, evaluates changes in the frequency of article publication, and identifies gaps in knowledge regarding these pathogens. A total of 35 peer-reviewed publications have been published from January 1941 through April 2019. Viral agents were evaluated in 11 studies, while 24 involved bacteria. Article publication has been mostly discontinuous in years prior to 2006. Salmonella spp. and avian influenza have been the most studied pathogens with 10 and 8 studies, respectively. Los Ríos and Valparaíso regions concentrate the highest number of studies and no research has been carried out in O'Higgins, Maule, and Aysén regions. Overall, information about pathogens in wild birds is scarce, highlighting the need for increased effort to identify pathogens being carried by avian reservoirs and evaluate the potential threat that they might pose for wildlife conservation, animal production, and the public health system in Chile.

As Repercussões Históricas da Pandemia da Gripe Influenza A (H1N1) no Brasil / Las Repercusiones Históricas de la Pandemia de Gripe de la Influenza a (h1n1) de Brasil / The Historical Repercussions of the Influenza Pandemic a (h1n1) in Brazil

Introdução: A pandemia da gripe influenza A (H1N1) ocorrida em 2009 foi considerada a primeira do Século XXI com importantes consequências para a saúde pública mundial. Objetivo: Analisar as repercussões da pandemia da gripe influenza A (H1N1) no Brasil. Método: Trata-se de um estudo histórico-social, cujas fontes diretas utilizadas foram documentos escritos. Discussão e Resultados: As estratégias empreendidas evidenciadas foram implementadas pelo Ministério da Saúde para conter o avanço da doença no país. Entre essas a Carta Aberta, a Nota Técnica sobre Emergência de Saúde Pública de Importância Internacional e o Plano Brasileiro de Preparação para Enfrentamento de uma Pandemia de Influenza. Considerações Finais: Evidenciamos que as autoridades de saúde investiram na luta contra a pandemia no contexto das recomendações da Organização Mundial da Saúde e das demandas de saúde da população brasileira frente aos desafios provocados pela gripe influenza A (H1N1).

Introduction: The Influenza Pandemic type A(H1N1), which occured in 2009, was considered the first of the twenty-first century with important consequences for all the public health systems around the world. Objective: To analyze the implications of the influenza pandemic A H1N1 on the public health system in Brazil. Method: qualitative research, with a socio-historical approach based on direct sources which consisted of written documents. Discussion and Results: The evidenced strategies were implemented by the Ministry of Health to contain the progress of the disease in the country. Among these strategies were an Open Letter, a Technical Note on Public Health Emergency of International Concern e and the Brazilian Preparation Plan for Coping with Pandemic Influenza. Final Considerations: It has been demonstrated that the Health Authorities invested in the fight against the Pandemic, meeting the recommendations of the World Health Organization as well as the health demands of the Brazilian population in the face of the challenges which the H1N1 epidemic represented.

Introducción: La Pandemia de Influenza tipo A (H1N1) ocurrió en 2009, fue considerada la primera del Siglo XXI con importantes consecuencias para la salud pública mundial. Objetivo: Analizar las implicaciones de la pandemia de gripe influenza A H1N1 en Brasil. Método: Investigación cualitativa, con abordaje histórico-social, dónde utilizaron como fuentes directas documentos escritos. Discusión Resultados: El Ministerio de la Salud implementó las estrategias emprendidas evidenciadas para contener el progreso de la enfermedad en el país. Entre ellas está la Carta Abierta, la Nota Técnica sobre Emergencia de Salud Pública de Importancia Internacional y el Plan Brasileño para el Enfrentamiento de una Pandemia de Influenza. Consideraciones finales: Podemos evidenciar que las autoridades de salud invirtieron en la lucha contra la Pandemia estando en concordancia con las ecomendaciones de la Organización Mundial de la Salud y de las demandas de salud de la población brasileña frente a los desafíos que impuso la epidemia H1N1.

Evaluation of Immune Responses and Histopathological Effects against Gamma Irradiated Avian Influenza (Sub type H9N2) Vaccine on Broiler Chicken

Abstract Vaccination is a good strategy for the prevention of avian influenza virus. In this research Gamma Irradiated Avian Influenza (Sub type H9N2) Vaccine (GAIV) was prepared by 30 kGy irradiation and used for vaccination of broiler chickens. The purpose was a comparison of immune responses in the two routes of administration for the GAIV vaccine; intranasal and subcutaneously, use of Montanide ISA70 and Trehalose accompanied with irradiated vaccine and compare with formalin vaccine. The Influenza Virus A/Chicken/IRN/Ghazvin/2001/H9N2 was irradiated and used for vaccine formulation, and formalin inactivated AIV was used as conventional vaccine. Chickens were vaccinated by GAIV with and without Trehalose, GAIV and formalin vaccines with ISA70, two routes of administration were intranasal and subcutaneously. All the vaccinated chickens showed a significant increase in antibody titration. The most significant increase of antibody titration was in irradiated vaccine plus Trehalose groups intranasal and subcutaneously. After the first and second intranasal vaccination, the amount of IFN-gamma increased in the irradiated vaccine plus Trehalose group compared to other groups. However, most of the vaccinated groups did not show any significant increase of IFN-α concentration. Histopathological examination revealed lymphocyte infiltration (++), foci dispersed of hemorrhage and edema in intranasal vaccination groups and in addition to these, thickening of alveolar septa was observed in the injection groups. GAIV vaccine can be a good candidate for vaccine preparation, and Trehalose as a stabilizer protects viral antigenic proteins, also makes more absorbance of antigen by the inhalation route. In vaccinated chickens the ulcers in injected vaccines were lower than intranasal vaccines.

Hospitalizaciones y mortalidad asociada a influenza, Honduras. 2011-2015 / Hospitalizations and deaths associated with Influenza, Honduras. 2011-2015

La carga de enfermedad por influenza está bien documentada en países de clima templado, pero hasta la fecha en Honduras solo se ha realizado un estudio, siendo este el segundo con respecto a la carga médica asociada a influenza. Objetivo: Estimar el número de hospitalizaciones y defunciones, debidos a la influenza, como causante de las infecciones respiratorias agudas en la población. Material yMétodos: Se realizó un estudio descriptivo retrospectivo. Seutilizó tres fuentes de datos secundarias:registros de todos los egresos hospitalarios, resultados de detección viral por influenza y proyecciones de población por grupos de edad. Se estimó la tasa de incidencia y su intervalo de confianza al 95%, combinando las tres fuentes de datos. Resultados: Las hospitalizaciones en las infecciones respiratorias agudas graves (IRAG) J09-J18 asociadas a influenza en el 2011-2015 son mayores en los menores de cinco años, en donde las hospitalizaciones son mayores en los años 2013 con 68.2 (IC 95%: 64.2-72.1) casos por 100, 000 habitantes. En el periodo 2011-2015. Las tasas de incidencia en las defunciones de IRAG asociadas a influenza1.Doctor(a) en medicina y cirugía.2.Doctor(a) en Pediatría3.Nivel Básico de Epidemiologia de Campo del FETP4.MSc.Epidemiólogo del FETP, coordinador de las enfermedades Transmisibles de la unidad devigilancia de la salud, Secretaria de Salud de HondurasAutor de correspondencia: Hommer Mejía, homams2003@yahool.comRecibido: Aprobado: (J09-J18) fueron mayores en el año 2014 con 1 caso (IC 95%: 0.4-1.6) por 100 000 habitantes. La circulación por influenza comenzó a incrementarse a partir de agosto del 2011 luego en los años 2012-2015 con picos altos durante los meses de octubre y noviembre. Conclusión: La carga médica asociada a influenza representa un impacto para los servicios de salud de Honduras, siendo los grupos de población en edades extremas, los que más hospitalizaciones y muertes presentaron. Se sugiere promover la vacunación contra influenza con la composición de cepas circulantes en el país y en temporada apropiada, enfatizando en los grupos más vulnerables de la población...(AU)

Pacientes con Influenza A subtipo H3N2 y soporte ventilatorio durante el brote estacional en una central de emergencias en Argentina / Patients with Influenza A Subtype H3N2 and Ventilatory Support During A Seasonal Outbreak in an Emergency Department in Argentina

Objetivo: Describir las características de los pacientes con Influenza A subtipo H3N2 y requerimiento de soporte ventilatorio durante el brote del 2017, así como la evolución y los resultados clínicos. Materiales y métodos: Cohorte retrospectiva. Se incluyeron todos los pacientes con diagnóstico confirmado de H3N2 durante el mes de junio 2017 con requerimientos de asistencia respiratoria mecánica invasivo, no invasivo, terapia de alto flujo por cánula nasal y/o presión continua en la vía aérea que consultaron a la central de emergencias. Resultados: Se incluyeron 34 pacientes, 52.9% hombres, media de edad 81 (DE 10) años. Las principales comorbilidades de los pacientes al ingreso fueron: 73.5% hipertensión arterial, 44.1% enfermedad pulmonar obstructiva crónica y 76.5% insuficiencia cardíaca congestiva. La media del score de Charlson fue de 6 (DE 2), la mediana de APACHE II fue de 17 (IIC 14-20) y la de SOFA al día 1 de 5 (IIC 3-7). Al ingreso, 23 pacientes requirieron ventilación no invasiva, 5 presión continua en la vía aérea, 4 asistencia respiratoria mecánica invasiva y 2 terapia de alto flujo. Se registró un 47.8% (IC95% 26.8-69.4) de falla de la ventilación no invasiva y finalmente el 38.2% fueron intubados y ventilados mecánicamente. La mortalidad hospitalaria fue de 52.9% (IC95% 35.1-70.2). Conclusiones: se observó una alta mortalidad en una población añosa y comórbida durante el brote de H3N2. La mayoría realizó una prueba de ventilación no invasiva al ingreso, un alto porcentaje falló. El cuadro inicial pudo ser interpretado como enfermedad pulmonar obstructiva crónica reagudizada y/o insuficiencia cardíaca congestiva.

Patients with Influenza A Subtype H3N2 and Ventilatory Support During A Seasonal Outbreak in an Emergency Department in Argentina / Pacientes con Influenza A subtipo H3N2 y soporte ventilatorio durante el brote estacional en una central de emergencias en Argentina

Objective: To describe the characteristics of patients with influenza A subtype H3N2 requiring ventilatory support during the 2017 outbreak, as well as the evolution of the disease and clinical results. Materials and Methods: Retrospective cohort. We included all patients admitted to the Emergency Department with confirmed diagnosis of H3N2 during June 2017, requiring invasive or noninvasive mechanical respiratory assistance, high-flow nasal cannula treatment or continuous airway pressure. Results: 34 patients were included; 52.9% men, mean age 81 years (Standard Deviation [SD] 10). Main comorbidities of patients on admission were: 73.5% hypertension, 44.1% chronic obstructive pulmonary disease and 76.5% congestive heart failure. The mean Charlson Index score was 6 (SD 2), the APACHE II median (Acute Physiology and Chronic Health Evaluation II) was 17 (IQR 14-20) and the SOFA median (Sequential Organ Failure Assessment) on day 1 was 5 (IQR 3-7). On admission, 23 patients required noninvasive ventilation, 5 continuous positive airway pressure, 4 invasive mechanical ventilation and 2 high-flow nasal cannula therapy. The rate of noninvasive ventilation failure was 47.8% (95% CI [confidence interval] 26.8-69.4) and finally 38.2% of patients were intubated and mechanically ventilated. Hospital mortality was 52.9% (95% CI 35.1-70.2). Conclusions: A high mortality rate was observed among elderly patients with comorbidities during the H3N2 outbreak. Most patients underwent a noninvasive ventilation trial on admission, however a high percentage failed. The initial condition could have been interpreted as acute chronic obstructive pulmonary disease or congestive heart failure.

Características clínicas de pacientes pediátricos internados por Influenza A: comparación de dos subtipos virales (H1N1) y (H3N2) / Clinical characteristics of pediatric patients hospitalized due to Influenza A: comparison of two viral subtypes (H1N1 and H3N2)

Influenza is a respiratory disease ocasionated by influenza virus A and B. Is a disease with high morbi-mortality world-wide. Influenza produces an acute febrile respiratory illness with cough, headache and myalgias for 3-4 days, with simptoms that may persist for as long as 2 weeks. There are three types of influenza virsuses: A, B and C, of whom the type a has a higher ability to originate pandemias and is subclassified according to their surface antigens: hemaglutinine (H) and neuraminidase (N). Of the capacity of mutation that has the influenza virus and the consequent expression of different proteins, can modify its virulence. The transmission route is through direct contact with secretetory repirations. The transmission route is through direct contact with secretetory repirations. The incubation period is scant, between 12-72 hs. The aim of this study was to compare the clinical characteristics demographicals and evolutive of pediatric patients hospitalized because by Influenze A: subtypes H1N1 (pdm2009) and H3N2. An observative study was performed, retrospective, using data of hospitalizations of children during the years 2016 and 2017 with influenza A confirmed by laboratory. The study also, aimed to evaluate if the viral subtype constitutes a factor of risk, independent for complicated hospitalization (admission to intensive care and/or development of complications) in hospitalized children. The results obtained in the study are detailed in the paper. In conclusion, both viral subtypes affected mainly to children with risk factors. The viral subtype H1N1 was related with higher severety in hospitalized children. is of most importance to perform preventive works, specially in vulnerable groups, offering a good cover of immunizations. The clinical parameters arae commented (AU)

Aspectos clínicos de la infección por influenza en el Hospital Metropolitano de Quito, Ecuador, entre noviembre de 2017 y febrero 2018 / Clinical aspects of influenza infection at the Metropolitan Hospital of Quito, Ecuador, between November 2017 and February 2018

Introducción: la influenza es altamente contagiosa. Sus manifestaciones sintomáticas son variables; 10% presenta síntomas severos que pueden deberse a factores propios del huésped o a la cepa del virus. Objetivo: describir el perfil clínico del brote de influenza en un hospital privado de Quito-Ecuador. Materiales y métodos: estudio retrospectivo observacional en pacientes con influenza atendidos en los Servicios de Emergencia y Hospitalización del Hospital Metropolitano de Quito. Resultados: se registraron 422 casos de influenza. El síntoma más frecuente fue la tos (83%). 69,1% recibió oseltamivir, 26,5% fue tratado con oseltamivir y antibioticoterapia. 203 pacientes fueron hospitalizados (48,1%), de ellos 46,8% fueron menores de 5 años, 60% requirió aporte de oxígeno, la complicación más frecuente fue la neumonía (38,9%), 9 ingresaron a cuidados intensivos y 4 fallecieron. Conclusión: la influenza causa altas tasas de morbilidad y graves complicaciones.

Abstract: Background: Influenza is highly contagious. It presents variable clinical manifestations. 10% presents severe symptoms that can be due to factors associated with the infected individual as well as the virus strain. Objective: To describe clinical characteristics of influenza outbreak in a private hospital in Quito-Ecuador. Materials and methods: Retrospective observational study of patients with influenza who were admitted to Emergency and Hospitalization of Hospital Metropolitano of Quito. Results: 422 influenza cases were identified. The most frequent symptom was cough (83%). 69.1% was treated with oseltamivir and 26.5% with oseltamivir and antibiotics. 203 patients were hospitalized (48.1%), of which 46.8% were children less than 5 years of age. 60% required oxygen, the most frequent complication was pneumonia (38.9%). 9 patients were admitted to intensive care unit. 4 patients died. Conclusions: Influenza causes high morbidity rates and severe complications. Key words: influenza, complications, hospitalization

The difference of detection rate of avian influenza virus in the wild bird surveillance using various methods

Korea is located within the East Asian-Australian flyway of wild migratory birds during the fall and winter seasons. Consequently, the likelihood of introduction of numerous subtypes and pathotypes of the Avian influenza (AI) virus to Korea has been thought to be very high. In the current study, we surveyed wild bird feces for the presence of AI virus that had been introduced to Korea between September 2017 and February 2018. To identify and characterize the AI virus, we employed commonly used methods, namely, virus isolation (VI) via egg inoculation, real-time reverse transcription-polymerase chain reaction (rRT-PCR), conventional RT-PCR (cRT-PCR) and a newly developed next generation sequencing (NGS) approach. In this study, 124 out of 11,145 fresh samples of wild migratory birds tested were rRT-PCR positive; only 52.0% of VI positive samples were determined as positive by rRT-PCR from fecal supernatant. Fifty AI virus specimens were isolated from fresh fecal samples and typed. The cRT-PCR subtyping results mostly coincided with the NGS results, although NGS detected the presence of 11 HA genes and four NA genes that were not detected by cRT-PCR. NGS analysis confirmed that 12% of the identified viruses were mixed-subtypes which were not detected by cRT-PCR. Prevention of the occurrence of AI virus requires a workflow for rapid and accurate virus detection and verification. However, conventional methods of detection have some limitations. Therefore, different methods should be combined for optimal surveillance, and further studies are needed in aspect of the introduction and application of new methods such as NGS.

Pathogenicity of clade 2.3.4.4 H5N6 highly pathogenic avian influenza virus in three chicken breeds from South Korea in 2016/2017

In 2016, novel H5N6 highly pathogenic avian influenza virus emerged in Korea. During the outbreak, the virus caused the largest culling, especially in brown chicken lines. We determined the pathogenicity and transmissibility of the virus in 2 white chicken lines of the specific pathogen-free chickens, broilers and brown chicken line of Korean native chicken (KNC). A KNC had a longer virus shedding period and longer mean death time than others. Our study showed that this characteristic in the KNC might have contributed to a farm-to-farm transmission of the brown chicken farms.

Novel application of Influenza A virus-inoculated chorioallantoic membrane to characterize a NP-specific monoclonal antibody for immunohistochemistry assaying

Monoclonal antibodies (MAbs) are widely applied in disease diagnoses. Herein, we report a MAb, WF-4, against Influenza A virus nucleoprotein (NP), its broad response with Influenza A virus, and its application in an immunohistochemistry (IHC) assay. WF-4 was screened by immunofluorescence assay (IFA). The results showed that its reactivity with baculovirus-expressed full-length recombinant NP (rNP) in Western blot (WB), indicating its IHC applicability. Fifteen Influenza A virus (reference subtypes H1 to H15) infected chicken embryonated chorioallantoic membranes (CAM), fixed by formalin, were all detectable in the WF-4-based IHC assay. Also, the reactivity of the IHC test with NP from experimentally inoculated H6N1 and from all recent outbreaks of H5 subtype avian Influenza A virus (AIV) field cases in Taiwan showed positive results. Our data indicate that CAM, a by-product of Influenza A virus preparation, is helpful for Influenza A virus-specific MAb characterization, and that the WF-4 MAb recognizes conserved and linear epitopes of Influenza A virus NP. Therefore, WF-4 is capable of detecting NP antigens via IHC and may be suitable for developing various tests for diagnosis of Influenza A virus and, especially, AIV infection.