Avian Influenza

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Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza

Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza

31. Currently, wildlife health problems are being created or exacerbated by unsustainable activities such as habitat loss or degradation, which facilitates closer contact between domestic and wild animals. Many advocate that to reduce risk of avian influenza and other bird diseases, there is a need to move to markedly more sustainable systems of agriculture with significantly lower intensity systems of poultry production. These need to be more biosecure, separated from wild waterbirds and their natural wetland habitats, resulting in far fewer opportunities for viral cross-infection and thus pathogenetic amplification (Greger 2006). There are major animal and human health consequences (in terms of the impact on economies, food security, and potential implications of a human influenza pandemic) of not strategically addressing these issues. However, to deliver such an objective in a world with an ever-growing human population, and with issues of food- security in many developing countries, will be a major policy challenge.
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Avian influenza in Latin America: A systematic review of serological and molecular studies from 2000 2015

Avian influenza in Latin America: A systematic review of serological and molecular studies from 2000 2015

Avian influenza or bird flu is a highly contagious acute viral disease that can occur in epi- demics and cross-border forms in poultry and wild birds. The characteristics of avian influ- enza viruses (AIVs) allow the emergence of new viral variants, some with zoonotic and pandemic potential. AIVs have been identified in Latin America; however, there is a lack of understanding of these viruses at the regional level. We performed a systematic literature review on serological or molecular evidence of AIVs circulation in Latin America. Methods were designed based on the PRISMA and STROME guidelines. Only peer-reviewed studies published between 2000 to 2015 and data was analysed based on country, viral subtype, avian species, and phylogenetic origins. From 271 studies initially found only twenty-six met our inclusion criteria. Evidence of AIVs infection was found in most Latin American coun- tries, with Mexico as the country with the largest number of conducted studies and reported cases during the period analysed, followed by Chile and Argentina. Most of the AIVs were early reported through surveillance systems and at least 14 different subtypes of influenza viruses were reported in birds, and the presence of both low (92.9%) and high (7.1%) patho- genic AIVs was shown in Latin America. Of the reported AIVs in Latin America, 43.7% belong to migratory birds, 28.1% to local wild birds, and 28.1% to poultry. The migratory bird population mainly comprises families belonging to the orders Anseriformes and Charadri- formes. We highlight the importance of epidemiological surveillance systems and the possi- ble role of different migratory birds in the transmission of AIVs within the Americas. Our findings demonstrate the limited information on AIVs in Latin America and highlight the need of more studies on AIVs at the regional level, particularly those focused on identifying the endemic subtypes in regional wild birds.
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Ramsar COP10 DR 21 Draft Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza H5N1

Ramsar COP10 DR 21 Draft Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza H5N1

recognised that, as well as the direct impacts of HPAI H5N1 on susceptible birds, public attitudes (and therefore support for wetland conservation, particularly of Ramsar sites and other wetlands of importance for waterbirds) could be negatively affected by concerns about the possible role of waterbirds in the spread of HPAI H5N1. Parties at COP9 were also greatly concerned that in many countries there was a significant lack of information and, in some countries, public misunderstanding, about important issues related to the spread of HPAI, the risks it may pose, and how to anticipate and respond to outbreaks of HPAI. Accordingly COP9 agreed Resolution IX.23 on Highly pathogenic avian influenza and its consequences for wetland and waterbird conservation and wise use. This Resolution inter alia called on the Convention’s Scientific and Technical Review Panel (STRP) to develop practical advice that could assist countries in responding to this serious and rapidly developing situation. 6. In particular, Ramsar COP9 requested the STRP, with the Scientific Task Force on Avian
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STRP draft Resolution and guidance on Highly Pathogenic Avian Influenza (HPAI)

STRP draft Resolution and guidance on Highly Pathogenic Avian Influenza (HPAI)

Given the ecology of the natural hosts of LPAI viruses, it is unsurprising that wetlands play a major role in the natural epidemiology of avian influenza. As with many other viruses, particles survive longer in colder water (Lu et al. 2003; Stallknecht et al. 1990b), and the virus is strongly suggested to survive over winter in frozen lakes in Arctic and sub-Arctic breeding areas. Thus, as well as the waterbird hosts, these wetlands are probably a permanent reservoir of LPAI virus (Rogers et al. 2004; Smith et al. 2004) (re-)infecting waterbirds arriving from southerly areas to breed (shown in Siberia by Okazaki et al. 2000 and Alaska by Ito et al. 1995). Indeed, in some wetlands used as staging grounds by large numbers of migratory ducks, avian influenza viral particles can be readily isolated from lake water (Hinshaw et al. 1980).
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Avian Influenza Infection Dynamics in Minor Avian Species

Avian Influenza Infection Dynamics in Minor Avian Species

An experimental infection with highly pathogenic avian influenza virus (HPAIV) and low pathogenic avian influenza virus (LPAIV) was carried out in red-legged partridges (Alectoris rufa) in order to study clinical signs, gross and microscopic lesions, and viral distribution in tissues and viral shedding. Birds were infected with a HPAIV subtype H7N1 (A/Chicken/Italy/5093/1999) and a LPAIV subtype H7N9 (A/Anas crecca/Spain/1460/2008). Uninoculated birds were included as contacts in both groups. In HPAIV infected birds, the first clinical signs were observed at 3 dpi, and mortality started at 4 dpi, reaching 100% at 8 dpi. The presence of viral antigen in tissues and viral shedding were confirmed by immunohistochemistry and quantitative real time RT-PCR (qRRT-PCR), respectively, in all birds infected with HPAIV. However, neither clinical signs nor histopathological findings were observed in LPAIV infected partridges. In addition, only short-term viral shedding together with seroconversion was detected in some LPAIV inoculated animals. The present study demonstrates that the red-legged partridge is highly susceptible to the H7N1 HPAIV strain, causing severe disease, mortality and abundant viral shedding and thus contributing to the spread of a potential local outbreak of this virus. In contrast, our results concerning H7N9 LPAIV suggest that the red-legged partridge is not a reservoir species for this virus.
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Avian influenza and wetlands

Avian influenza and wetlands

unsustainable activities such as habitat loss or degradation, which facilitates closer contact between domestic and wild animals. Many advocate that to reduce risk of avian influenza and other bird diseases, there is a need to move to markedly more sustainable systems of agriculture with significantly lower intensity systems of poultry production. These need to be more biosecure, separated from wild waterbirds and their natural wetland habitats, resulting in far fewer opportunities for viral cross-infection and thus pathogenetic amplification (Greger 2006). There are major animal and human health consequences (in terms of the impact on economies, food security, and potential implications of a human influenza pandemic) of not strategically addressing these issues. However, to deliver such an objective in a world with an ever-growing human population, and with issues of food-security in many developing countries, will be a major policy challenge.
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Aspectos actuales de la influenza aviaria

Aspectos actuales de la influenza aviaria

The Center for Diseases Control and Prevention of Atlanta Georgia USA, has considered to the avian influenza virus A, Subtype H5NI, the number one world’s health threat, that remains like the more viable candidate for an influenza pan- demic. In the last three years the H5NI strain surmounted the barrier species with fatal human and animal cases, and historically imprecedent outbreaks in poultry (more than 4200), and wild birds, and by his geographical extension: more than 50 countries in Asia, Africa, Europe and Middle East, and his highest mortality. The H5NI strain to has an extraordinary structural, genetical, clinical and epidemiologi- cal similitudes, with the pandemic strain of the 1918 Influ- enza pandemic, actually are spreading following the migra- tory paths of wild birds.
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Anlisis del genoma de un virus atpico de influenza aviar H5N2 de baja patogenicidad de origen mexicano

Anlisis del genoma de un virus atpico de influenza aviar H5N2 de baja patogenicidad de origen mexicano

The genome of the A/chicken/Mexico/2007 (H5N2) virus encodes 11 pro- teins (Neuman and Kawaoka, 2011). The genome lacks the PB1-F2 gene, which has been associated with increased pathogenicity in avian hosts (Marjuki et al., 2010). The viral genome does encode the PA-X protein that has been shown to represses viral replication and immune response in the mouse and chicken. To- gether, these findings explain the virus’s low-pathogenicity in vivo (Jagger et al., 2012; Hayashi et al., 2015; Hu et al., 2015). The genome of the A/chicken/Mex- ico/2007 virus contains of a conserved ribosomal frameshifting motif that allows for expression of the PA-X gene in low-pathogenic influenza A virus in avian species (Hu et al., 2015). The HA1 receptor binding sequence in this viral genome encode amino acid residues Q226 and G228, which preferentially bind to avian sialic acid receptors in α2-3 linkages (Ha et al., 2001; Zhao et al., 2012). The HA gene of A/chicken/Mexico/2007 has few basic amino acids at the cleavage site of the HA (V-P-Q-R-E-X-R | G-L), which is characteristic of most avian influenza viruses with low pathogenicity (Berhane et al., 2014; Chang-Chun et al., 2014; Wood et al., 1996). However, the lack of a specific potential N-glycosylation site at position 11 near the HA cleavage site could be associated with increased pathogenicity (Desh- pande et al., 1987). The neuraminidase exhibits a 20 amino acid deletion at the stalk region, which is an adaptive feature to poultry (Li et al., 2011).
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Aportaciones de la genmica y la bioinformtica al nuevo virus de la influenza A (H1N1) y su impacto en la medicina

Aportaciones de la genmica y la bioinformtica al nuevo virus de la influenza A (H1N1) y su impacto en la medicina

sobre la situación que guarda el virus A (H1N1) en el Hemis- ferio Sur de nuestro planeta; con la estacionalidad, que se presenta en los meses de mayo a octubre, con el inicio de los reportes de influenza. Se determinó que en cinco países de esa región, el nuevo virus A (H1N1) es el subtipo dominante que actualmente circula y se ha detectado en el 89% de los casos confirmados en el Hemisferio Sur, en comparación al 66% de los casos del Hemisferio Norte. El estudio respecto al nuevo virus A (H1N1) muestra que permanece antigéni- camente sin cambio, desde su identificación inicial en abril del 2009; ello indica que el virus mantiene sus característi- cas iniciales y presentes también en la cepa empleada en la preparación de la actual vacuna pandémica. El 26 de mayo de 2009, la OMS recomendó la cepa A/California/7/2009 para el desarrollo de esta vacuna. En los Estados Unidos, los CDC han realizado la secuencia de más de 1,484 genes de aproximadamente 415 aislamientos virales, de 331 casos o pacientes que incluyen a 256 casos provenientes de Nortea- mérica, 30 casos de Sudamérica (Argentina, Brasil, Chile Bolivia, Ecuador, Uruguay, Paraguay y Colombia) y Suri- nam; 19 casos de 12 países de América Central y el Caribe, 10 casos de Asia, cuatro casos de Europa, ocho casos de África y dos casos de Oceanía (específicamente Nueva Ze- landa). Se ha concluido que los genomas de estos aislamien- tos presentan un alto grado de similaridad y no muestran diferencias importantes debido a sus tiempos de aparición o localización geográfica. Los virus estudiados continuaron
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Utilidad de la prueba rpida de influenza durante la epidemia de influenza A(H1N1) en una unidad de medicina familiar  Mxico, 2009

Utilidad de la prueba rpida de influenza durante la epidemia de influenza A(H1N1) en una unidad de medicina familiar Mxico, 2009

27. Uyeki TM. Influenza diagnosis and treatment in children: a review of studies on clinically useful tests and antiviral treatment for influenza. Pediatr Infect Dis J 2003; 22:164– 77. In: Harper SA, Bradle JS, Englund JA, File TM, Gra- venstein S, Hayden FG, McGeer AJ, Neuzi KM, Pavia AT, Tapper ML, Uyeki TM, Zimmerman RK. Seasonal Influenza in Adults and Children— Diagnosis, Treatment, Chemopro- phylaxis, and Institutional Outbreak Management: Clinical Practice Guidelines of the Infectious Diseases Society of America. IDSA Guidelines for Seasonal Influenza in Adults and Children CID (48), 2009: 1003-1032.
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Plan de manejo de embarazda e influenza

Plan de manejo de embarazda e influenza

Vacuna contra la influenza A(H1N1). La vacuna monovalente contra la influenza A(H1N1) que se aplique a las mujeres embarazadas debe ser la INACTIVADA SIN ADYUVANTE. Las que contienen virus atenuados (administradas por inhalación) están contraindicadas durante el embarazo porque eventualmente inducen la infección. Se ha comunicado que la vacuna A(H1N1) produce transferencia pasiva de anticuerpos al feto y, además, que aplicada oportunamente reduce los cuadros de infección respiratoria en 29, 36 y 63% en el primero, segundo y tercer trimestre del embarazo, respectivamente.
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Neumona necrotizante hemorrgica y SARM AC como causa emergente

Neumona necrotizante hemorrgica y SARM AC como causa emergente

Se realizaron estudios de laboratorio y gabinete, los hemocultivos fueron negativos, el examen general de orina sin alteraciones, tinción de Gram y cultivo de expectoración con la presencia de cocos Gram positivos abundantes y posteriormente identificación de Staphylococcus aureus meticilino resistente, sensible a clindamicina, tetraciclina y trimetoprima-sulfametoxazol. Las serologías para Chla- mydophila pneumoniae, Legionella pneumophila, Myco- plasma pneumoniae, así como el antígeno para Legionella en orina fueron negativos. Hisopado para influenza A y B, así como PCR para influenza AH1N1 negativos. En la radiografía de tórax inicial, se observó un infiltrado en lóbulo superior izquierdo. Posteriormente se realizó una segunda radiografía de tórax por el rápido deterioro clínico en la cual se evidenció progresión de la afectación pulmonar con infiltrados bilaterales. Se solicitó valoración por Neumología e Infectología decidiendo el ingreso a terapia intermedia con aislamiento respiratorio en cuarto con presión negativa; se inició cobertura empírica con ceftriaxona, moxifloxacino, vancomicina y oseltamivir. Un día después de su ingreso presentó deterioro severo con datos de insuficiencia respiratoria, así como pancitopenia, principalmente neutropenia absoluta y trombocitopenia grave, con tiempos de coagulación muy prolongados. Se realizó TC tórax (Figuras 1 a 3) en la cual se evidenció neumonía multilobar bilateral. Se traslado a la Unidad de Cuidados Intensivos, requiriendo apoyo con factor estimu- lante de colonias de granulocitos y aféresis plaquetarias; se sustituyó ceftriaxona por cefepime. Durante la intuba- ción presentó bradicardia extrema, actividad eléctrica sin pulso y paro cardiorrespiratorio, se realizaron maniobras de reanimación avanzadas, con respuesta a los 9 minutos, recuperando frecuencia cardiaca y pulso; se procedió a la colocación de marcapaso transcutáneo presentando nuevo evento de bradicardia durante la colocación y posterior- mente asistolia y paro cardiaco, iniciándose nuevamente maniobras de reanimación cardiopulmonar avanzadas. Durante las maniobras de reanimación cardiopulmonar se realizó ecocardiograma transtorácico documentándose acinesia global por asistolia y disociación electromecánica sin respuesta a manejo intensivo durante 25 minutos, por lo que se declaró muerte clínica.
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Avian invasions: from basic to applied research

Avian invasions: from basic to applied research

Developing risk assessment protocols is not an easy task. Because the invasion process is generally seen as highly idiosyncratic, there is a widespread perception that it is impossible to predict which species will invade in any given situation (Ehrlich 1989, Kolar and Lodge 2001). In birds, for example, a large number of species-traits have been proposed to influence establishment success (Newsome and Noble 1986, Blackburn and Duncan 2001a, Cassey 2001b, Kolar and Lodge 2001, Cassey et al. 2004, Jeschke and Strayer 2006) (see Table 4.1), but very few of these features have been supported firmly by empirical evidence (Duncan et al. 2003). This could indicate that only a few traits are relevant in determining the outcome of an introduction. If so, we can ask whether these few traits are sufficient to produce reliable risk assessment tools. Alternatively, the lack of success in identifying the features of successful invaders could reflect the low power of the tests used due to insufficient sample sizes or the failure to deal with biases and confounding effects associated with historical introductions (Blackburn and Duncan 2001a, Sol et al. 2008b). In this case, the solution is to re-analyse whether these features influence establishment success with a larger sample of introductions and using approaches that allow controlling for possible biases and confounding effects. To develop our quantitative risk assessments, we employ a global database documenting the outcome of 832 introductions of 202 avian species to new locations, 311 of which were successful. With this information, we test the predictive power of 17 traits that have been either demonstrated or suggested to be associated with establishment success (Table 4.1), using both the GLMM and tree regression approaches. We validate our risk assessment models with the subset of species introduced to Europe and North America. Finally, we compare the performance of both methods with a ranking system proposed for vertebrates in Australia (Bomford 2003).
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Comparacin del rendimiento diagnstico clnico versus la prueba rpida durante dos temporadas de influenza

Comparacin del rendimiento diagnstico clnico versus la prueba rpida durante dos temporadas de influenza

Introducción: Una reflexión de la pandemia de influenza en 2009 es la prioridad de la prescripción temprana de los antivirales, previniendo el uso injustificado de antibióticos. Objetivo: Describir la sintomatología que se asocia más al diagnóstico definitivo de influenza y comparar el rendimiento del diagnóstico clínico contra el diagnóstico arrojado por la prueba rápida. Material y métodos: Estudio retrospectivo, transversal, descriptivo y analítico. Se inclu- yeron pacientes con diagnóstico presuntivo de influenza admitidos en el Servicio de Urgencias del Hospital Español de México en dos temporadas consecutivas que van de octubre de 2016 a marzo de 2017 y de octubre de 2017 a marzo de 2018. Se formaron dos grupos: pacientes con PCR positiva (grupo A) y pacientes con PCR negativa (grupo B). Resultados: Se obtuvo un total de 857 pacientes con diagnóstico presuntivo clínico de influenza, de los cuales 537 se confirmaron con influenza por PCR (grupo A) y 320 fueron negativos para dicha prueba (grupo B). El síndrome conformado por tos, fiebre, rinorrea y artralgias tiene una especificidad de 92.2% en compara- ción con la prueba rápida de 99.1%. Conclusiones: El síndrome caracterizado por tos, fiebre, rinorrea, artralgias presentes durante los meses invernales tiene una alta especificidad para infección por el virus de la influenza.
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Mortalidad en Mxico por influenza y neumona (1990 2005)

Mortalidad en Mxico por influenza y neumona (1990 2005)

Objective. To estimate the impact of influenza vaccine in infants less than two years of age and in elders more than sixty-five years of age, through the analysis of mortality due to influenza and pneumonia in Mexico, between 1990 and 2005. To determine the seasonal pattern of mortality, the tendency of mortality by volume of deaths per seasonal period, and the speed rate of mortality. Material and methods. Data were taken from the Epidemiological and Statistical Mortality System (SEED-SSA per its abbreviation in Spanish). Results and conclusions. The analysis showed there is a tendency of deaths decrease at a rate of 509 deaths less per year in the infants group and 29 deaths less in the elders group. Also, the ascending tendency of mortal- ity was interrupted by vaccination. The vaccination inter- vention has a positive economic effect and also helps improve the quality of life. Therefore, its implementation is expected to lower hospital admissions and deaths.
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VIGILANCIA EPIDEMIOLOGICA DE LA INFLUENZA AVIAR EN LA REGION LAGUNERA

VIGILANCIA EPIDEMIOLOGICA DE LA INFLUENZA AVIAR EN LA REGION LAGUNERA

Los virus de influenza aviar se pueden clasificar como levemente patógeno (IALP) y altamente patógeno (IAAP) basándose en la severidad de la enfermedad. La mayoría de los virus de influenza aviar son levemente patógenos y típicamente causan poco o ningún signo clínico en las aves infectadas. Sin embargo, algunos tipos de virus IALP son capaces de mutar a IAAP en condiciones de campo. Los virus IAAP son del tipo extremadamente infeccioso la enfermedad ocasiona hasta 100% de mortalidad y se puede esparcir rápidamente (Tach, 2002).

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Notas sobre la influenza

Notas sobre la influenza

grupos usuales para el conocimiento y control de una epide- mia: 1) susceptibles; 2) infectados no enfermos pero sí in- fectantes; 3) enfermos infectantes; 4) pacientes graves que requieren atención hospitalaria de alta especialidad, inclu- yendo respiradores artificiales. Ya con este panorama se irán conociendo tasas de ataque, de morbilidad, de mortalidad y de letalidad. Sigue también el trabajo de epidemiología fina, la investigación en sus niveles de mayor laboriosidad e ins- trumentación. Habrá que recurrir a encuestas serológicas para conocer la prevalencia de infección, en cortes transversales periódicos. Necesitamos conocer si la influenza porcina, como zoonosis, está presente en nuestros animales más sus- ceptibles para responder a preguntas como la de ¿es este agente infeccioso para las aves de corral?, ¿se halla presente en nuestras porquerizas abundantes sobre todo en la región del Bajío pero también en muchos otros sitios? En caso afir- mativo para estas interrogantes, ¿se está dando la transmi- sión animal-humano?
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La influenza y su situación en Colombia

La influenza y su situación en Colombia

Varios mecanismos podrían originar el ingreso del virus al país. Por una parte, las aves migratorias portadoras pueden excretar virus a su paso por los sitios de asentamiento obligado tradicional, y contagiar a las aves nativas silvestres y domesticas u otros animales iniciando la cadena de transmisión entre aves y otras especies animales. Es posible que los viajeros que regresan de países afectados con brotes de influenza aviar pudieran estar infectados y actuar como fuentes de contaminación o contagio generando el primer caso con la posibilidad de diseminación en el país.; o una vez notificada la pandemia, la introducción de productos e insumos de uso en la industria animal contaminados con el virus pandémico, podría ser la fuente de transmisión de la influenza pandémica. Por ello desde los primeros meses del 2004, se ha intensificado la vigilancia mundial en busca de alguno de esos casos.
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Influenza

Influenza

En el mes de abril del 2009 se reconoció que en México circuló una nueva variante del virus de la influenza A. El análisis genómico de esta cepa del virus (influenza A humana H1N1 2009) indica que está estrechamente relacionado a un virus común de influenza porcina aislado en Norte América, Europa y Asia. Los segmentos que co- difican para el complejo de la polimerasa, hema- glutinina, proteína matriz, y no estructurales, muestran alta similitud con el virus porcino H1N2 de Norte América aislado a fines de los años no- venta. Otros subtipos descienden de un triple “re- arreglo genético” (triple-reassortant) del virus H3N2, que se han diseminado alrededor del mundo e infectado a humanos. Los segmentos que codifican para neuraminidasa y proteínas de la matriz del nuevo virus humano están distante- mente relacionados con los virus porcinos aisla- dos en Europa a inicio de los años noventa. A nivel mundial existe un esfuerzo por secuenciar e informar las secuencias del virus influenza. A la fecha hay 46 000 secuencias en el Virus Re- source of the National Center for Biotechnology In- formation (NCBI) (www.ncbi.nlm.nih.gov/geno- mes/FLU/FLU.html). Hasta mayo 25 del 2009, la base incluía secuencias de más de 220 cepas del virus influenza A (H1N1) de diferentes luga- res del mundo. El virus actual es una combina- ción de dos virus clásicos de influenza porcina, un virus aviar y un virus humano (Fig. 1). 8
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Influenza vaccine effectiveness in preventing hospitalisation of individuals 60 years of age and over with laboratory confirmed influenza, Valencia Region, Spain, influenza season 2016 17 / Ainara Mira Iglesias     et al

Influenza vaccine effectiveness in preventing hospitalisation of individuals 60 years of age and over with laboratory confirmed influenza, Valencia Region, Spain, influenza season 2016 17 / Ainara Mira Iglesias et al

Our IVE analysis was restricted to admissions 60 years of age and over because of small numbers in the other age groups. Other studies reported that confirmed cases of influenza A were predominant in adults aged over 65 years of age with a substantial increase in mortality among individuals in this age group [26]. We observed a significant residual protection of previous vaccination and a lower effect in those vaccinated only in the current season or in the current and any of the two previous seasons. This pattern of protection was consistent with preliminary estimates in Europe [12,28]. Our results showed that IVE estimates were lower in the primary analysis, when no current vaccina- tion rather than no current/no prior vaccination was used as reference group. This may be suggestive of residual protection (IVE for prior vaccination only). Interestingly, this residual protection may include vac- cination with the previous A(H3N2) vaccine strain A/ Switzerland/9715293/2013 used in 2015/16 season, perhaps because of some cross-reactivity. Because of the residual protection observed, our findings do not support that a possible antigenic mismatch among the A/Hong Kong/4801/2014 vaccine strain and the Table 2
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