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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Desfechos das gestações expostas ao vírus H1N1 e ao Oseltamivir no Rio Grande do Sul durante a pandemia de 2009

Silva, André Anjos da January 2014 (has links)
O presente trabalho aborda como questão central o desfecho das gestações expostas ao vírus Influenza A (H1N1) e, consequentemente, ao seu tratamento com o fármaco oseltamivir durante a pandemia do ano 2009. O vírus influenza A H1N1 é produto de vários rearranjos genéticos entre cepas dos vírus influenza previamente circulantes, alguns destes exclusivos de suínos ou de aves, e que se tornaram capazes de infectar humanos. A epidemia de influenza A (H1N1) teve início no México, e expandiu-se rapidamente para países do mundo inteiro, sendo declarada pandemia pela Organização Mundial da Saúde (OMS), aproximadamente dois meses após o aparecimento dos primeiros casos. As gestantes são consideradas um grupo de risco para complicações graves relacionadas ao vírus influenza H1N1, com grande morbidade e mortalidade observadas em epidemias anteriores do vírus Influenza. Quanto aos efeitos sobre o embrião-feto, os estudos a respeito do potencial teratogênico do vírus influenza ainda são limitados. A literatura não demonstrou, até o momento, efeitos adversos desse vírus sobre o embrião-feto. O tratamento específico consiste no uso de inibidores da neuraminidase, zanamivir e oseltamivir, dos quais apenas o último está disponível no Brasil. O objetivo geral da tese é avaliar as gestações expostas ao vírus H1N1 e submetidas ao tratamento com Fosfato de Oseltamivir. Os objetivos específicos são comparar gestantes expostas e não-expostas ao vírus Influenza A H1N1 quanto aos desfechos maternos e perinatais; avaliar os potenciais efeitos adversos da medicação em gestantes expostas ao oseltamivir; e avaliar a saúde e o desenvolvimento neuropsicomotor das crianças expostas durante a gravidez ao oseltamivir. Foi realizado um estudo de coorte prospectivo não controlado que avaliou gestantes com exposição ao vírus H1N1 e ao tratamento com Fosfato de Oseltamivir. A amostra consistiu nas 589 gestantes com sintomas suspeitos de Influenza A notificadas no Sistema de Informação de Agravos de Notificação - Influenza (SINAN-Influenza banco de dados do estado do Rio Grande do Sul). Os seguimentos de 424 gestantes foram realizados por contato telefônico, visita domiciliar, dados de prontuário médico ou Declaração de Nascido Vivo, por uma equipe treinada. . Foram obtidos 243 resultados de exames de PCR (polymerase chain reaction). Houve 163 (67%) casos confirmados de H1N1 e 80 (33%) Influenza não-H1N1. Houve 24 óbitos maternos, sendo 18 em H1N1. Houve 8 natimortos, sendo 5 filhos de gestantes expostas ao H1N1. Não houve diferença nos desfechos perinatais. Apenas um caso de malformação congênita (fenda palatina) foi observado em um bebe não exposto ao oseltamivir. Uso de oseltamivir foi identificado em 221 pacientes. Dessas, 86 gestantes apresentaram PCR positivo para Influenza A (H1N1) e 51 estavam no grupo não- H1N1. Reações adversas foram relatadas em 92 (42%) gestantes. Houve um maior número de reações adversas relatadas em pacientes não-H1N1 após o uso do oseltamivir. Ocorreram menos óbitos maternos (7,2%) nas que receberam oseltamivir comparativamente a 34,7% das mulheres que não foram tratadas (OR: 0,14, IC95%: 0,04-0,42, p=0,0003). Da mesma forma a frequência de natimortos foi menor (2,2%) nas tratadas, em comparação a 13,0% das não tratadas (OR: 0,15, IC95%: 0,03-0,89, p=0,03). Atrasos afetando dois ou mais marcos do desenvolvimento foram relatados em 10 (19,2%) de 52 crianças expostas ao oseltamivir durante o período gestacional e seguidas por no mínimo 36 meses. Essa frequência está acima do esperado para a população brasileira (15%). Em conclusão, espera-se que o presente trabalho seja capaz de contribuir para um melhor entendimento a respeito do potencial teratogênico do vírus Influenza A (H1N1) e de seu tratamento com o fármaco oseltamivir. Estudos futuros serão decisivos no estabelecimento de condutas clínicas no que diz respeito ao tratamento e manejo geral dessa condição nesse grupo específico de pacientes. / The present investigation approaches as central issue the outcomes of pregnancies exposed to the Influenza A (H1N1) virus and, consequently, to its treatment with the drug oseltamivir during the pandemic in the year 2009. The Influenza A H1N1 virus is the product of multiple genetic rearrangements among strains of influenza that had previously been circulating. Some of these were unique to swine and birds and became capable of infecting humans. The influenza A (H1N1) epidemic began in Mexico and rapidly spread to other countries around the world and was declared a pandemic by the World Health Organization (WHO) approximately two months after the first cases appeared. Pregnant women are considered to be a group at risk of serious complications related to the H1N1 influenza virus, with high morbidity and mortality observed in previous Influenza virus epidemics. As for effects on the embryo/fetus, there are still few studies on the teratogenic potential of the influenza virus. The literature has not demonstrated, so far, adverse effects of this virus on the embryo/fetus. The specific treatment is the use of the neuraminidase inhibitors, zanamivir and oseltamivir, of which only the latter is available in Brazil. The general aim of this work is to evaluate pregnancies exposed to the Influenza A (H1N1) virus and submitted to treatment with Oseltamivir Phosphate. Specific objectives are to compare pregnant women exposed and not exposed to the Influenza A H1N1 virus as on maternal and perinatal outcomes; evaluate potential adverse effects of medication in pregnant women exposed to oseltamivir; and evaluate the health and neurodevelopment in children exposed during pregnancy to oseltamivir. We performed an uncontrolled prospective cohort study that evaluated pregnancies with exposure to the H1N1 Influenza virus and its treatment with Oseltamivir Phosphate. The sample consisted of 589 pregnant women with suspected symptoms of Influenza A who were reported in the Information System for Notifiable Diseases - Influenza (SINAN-Influenza, Rio Grande do Sul Database). Follow-up of 424 pregnancies was conducted via telephone, home visit, medical records or Live Birth Certificate, by a trained team. PCR (polymerase chain reaction) was performed in 243 individuals. There were 163 (67%) confirmed cases of H1N1 and 80 (33%) non-H1N1 Influenza virus. There were twenty-four maternal deaths, 18 of these were H1N1+ patients. Eight stillbirths were reported, five of these were for H1N1+ pregnant women. There were no differences in perinatal outcomes. Only one cleft palate was reported in a newborn whose mother did not use oseltamivir. Use of oseltamivir phosphate was identified in 221 patients. Of this, there were 86 confirmed cases of Influenza A (H1N1) and 51 non-H1N1 Influenza virus. Adverse reactions were reported in 92 (42%) pregnancies. There were a higher number of adverse effects reported in non-H1N1 patients after the use of oseltamivir. There were fewer maternal deaths (7.2%) in those who received oseltamivir compared to 34.7% of women who were not treated (OR: 0.14, CI95%: 0.04-0.42, p=0.0003). Similarly, the frequency of stillbirth was lower (2.2%) in treated as compared to 13.0% of the untreated women (OR: 0.15, CI95%: 0.03- 0.89, p=0.03). Developmental delay in two or more skills was reported in 10 (19.2%) of 52 children exposed prenatally to oseltamivir and followed for at least 36 months. This rate is above of expected for the Brazilian population (15%). In conclusion, it is expected that this work can contribute to a better understanding towards the potential teratogenic effect of Influenza A (H1N1) virus and its treatment with oseltamivir. Future studies will be decisive to the establishment of clinical practices about treatment and general management of this condition in this specific group of patients.
12

Mortalidade em gestantes por influenza A(H1N1)PDM09 no Brasil nos anos de 2009 e 2010

Souza, Líbia Roberta de Oliveira 05 September 2013 (has links)
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Medicina, Núcleo de Medicina Tropical, 2013. / Submitted by Larissa Stefane Vieira Rodrigues (larissarodrigues@bce.unb.br) on 2014-11-06T18:36:45Z No. of bitstreams: 1 2013_LíbiaRobertaDeOliveiraSouza.pdf: 1103965 bytes, checksum: 1dbd08ad6319a90b02749362cb1da2a9 (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2014-11-06T19:09:48Z (GMT) No. of bitstreams: 1 2013_LíbiaRobertaDeOliveiraSouza.pdf: 1103965 bytes, checksum: 1dbd08ad6319a90b02749362cb1da2a9 (MD5) / Made available in DSpace on 2014-11-06T19:09:48Z (GMT). No. of bitstreams: 1 2013_LíbiaRobertaDeOliveiraSouza.pdf: 1103965 bytes, checksum: 1dbd08ad6319a90b02749362cb1da2a9 (MD5) / Em abril de 2009 foram identificados os primeiros casos por Influenza A(H1N1)pdm09 e, em junho desse mesmo ano, foi declarada fase pandêmica por este novo subtipo. As gestantes foram identificadas precocemente como grupo de risco para complicações e óbito. O Brasil apresentou decréscimo de 51% na morte materna no período de 1990 e 2010, porém houve um incremento nesse indicador no ano de 2009, o qual pode ter sido influenciado por tal pandemia. O objetivo desse estudo foi descrever a mortalidade por Influenza A(H1N1)pdm09 entre gestantes no Brasil, nos anos de 2009 e 2010. Foi realizado um estudo descritivo sobre a mortalidade em gestantes empregando-se o método de relacionamento probabilístico entre os óbitos por todas as causas no Sistema de Informação sobre Mortalidade e as notificações no Sistema de Informação de Agravos de Notificação em mulheres de 10 a 59 anos. Foram realizados 7 passos de blocagem e as variáveis nome e data de nascimento foram utilizadas para o pareamento. Foram identificados óbitos subnotificados e subinformados no SIM e calculada a proporção de mortes maternas por Influenza A(H1N1)pdm09. Foram notificadas 6.695 gestantes no período estudado e confirmados 3.301 (49,3%) casos por Influenza A(H1N1)pdm09. Em 2009, 52,% (3.164/6.000) dos casos foram confirmados, o equivalente a 95,8% no período de estudo. Dentre o total de gestantes notificadas, 371 (5,5%) evoluíram para óbito, sendo 61,2% (227) dos óbitos confirmados para Influenza A(H1N1)pdm09. Enquanto menos de 3% da população de mulheres em idade fértil era gestante, mais de 30% das mulheres em idade fértil, que evoluíram para óbito por Influenza A(H1N1)pdm09 eram gestantes. Quarenta e dois por cento dos óbitos tinham registro de pelo menos uma comorbidade e mais de 50% estavam no terceiro trimestre da gestação. O pico das mortes maternas pelo grupo das doenças do aparelho respiratório complicando a gravidez, parto e puerpério coincidiu com o pico dos óbitos em gestantes por influenza A(H1N1)pdm09. Após identificação dos óbitos subnotificados e subinformados em gestantes por Influenza A(H1N1)pdm09, foi evidenciado que, entre 9,9% e 9,0% das mortes maternas, em 2009, e entre 1,8% e 1,5%, em 2010, foram por Influenza A(H1N1)pdm09. Excluindo as mortes maternas por Influenza A(H1N1)pdm09, a Razão de Morte Materna não sofreria incremento em 2009. A pandemia pelo vírus Influenza A(H1N1)pdm09 foi responsável pelo aumento de morte materna em 2009, no Brasil, evidenciado por exagerada representação de gestantes entre os óbitos por Influenza A(H1N1)pdm09 nas mulheres em idade fértil e por elevação do número de mortes maternas. Recomenda-se que sejam realizados estudos sobre o uso de oseltamivir e da vacina contra influenza na mitigação dos óbitos por influenza em gestante. _______________________________________________________________________________________ ABSTRACT / In April 2009, the first cases of Influenza A(H1N1)pdm09 were identified and in June of that year was declared pandemic phase for this new subtype. Pregnant women were at increased risk of complications and death according to early reports on the pandemics epidemiology. Brazil had a 51% decrease in maternal deaths between 1990 and 2010, but there was an increase in this indicator in 2009, which may have been influenced by such a pandemic. The aim of this study was to describe mortality from Influenza A(H1N1)pdm09 among pregnant women in Brazil during the years 2009 and 2010. We conducted a descriptive study on mortality among pregnant women using the method of probabilistic record linkage between deaths from all causes in the Mortality information System (SIM) and reports of cases in women with 10-59 years-old. Seven blocking steps were executed and variables name and date of birth used for pairing. We identified underreported and under informed deaths in the SIM and calculated the proportion of maternal deaths due to Influenza A(H1N1)pdm09. During the study period, 6,695 pregnant women were reported and 3,301 (49.3%) were confirmed for influenza A(H1N1)pdm09. In 2009, 52% (3.164/6.000) of the cases were confirmed, equivalent to 95.8% in 2009-2010. Among the total number of pregnant women reported, 371 (5.5%) died, among then 61.2% (227) was confirmed as influenza A(H1N1)pdm09 deaths. While less than 3% of the population of women of childbearing age was pregnant, over 30% of them who have died due to Influenza A(H1N1)pdm09 were pregnant. Forty- two percent of recorded deaths had at least one known comorbidity, and over 50 % were in the third trimester of pregnancy. The peak of maternal deaths ordered by group of respiratory diseases complicating pregnancy, childbirth and puerperium coincided with the peak of deaths in pregnant women with influenza A(H1N1)pdm09. After identification of underreported and under informed deaths among pregnant women by Influenza A(H1N1)pdm09, it was shown that between 9.9% and 9.0% of maternal deaths in 2009 and between 1.8 % and 1.5 % in 2010 were due to Influenza A(H1N1)pdm09. Excluding maternal deaths due to Influenza A(H1N1)pdm09, the Maternal Mortality Ratio in Brazil did not suffer an increase in 2009. The pandemic of Influenza A(H1N1)pdm09 was responsible for the increase of maternal death in Brazil in 2009, evidenced by overrepresentation of deaths among pregnant women with Influenza A(H1N1)pdm09 in women of childbearing age and increased number of maternal deaths. It is recommended that studies on the use of oseltamivir or the influenza vaccine in mitigating influenza deaths in pregnant women.
13

Desfechos das gestações expostas ao vírus H1N1 e ao Oseltamivir no Rio Grande do Sul durante a pandemia de 2009

Silva, André Anjos da January 2014 (has links)
O presente trabalho aborda como questão central o desfecho das gestações expostas ao vírus Influenza A (H1N1) e, consequentemente, ao seu tratamento com o fármaco oseltamivir durante a pandemia do ano 2009. O vírus influenza A H1N1 é produto de vários rearranjos genéticos entre cepas dos vírus influenza previamente circulantes, alguns destes exclusivos de suínos ou de aves, e que se tornaram capazes de infectar humanos. A epidemia de influenza A (H1N1) teve início no México, e expandiu-se rapidamente para países do mundo inteiro, sendo declarada pandemia pela Organização Mundial da Saúde (OMS), aproximadamente dois meses após o aparecimento dos primeiros casos. As gestantes são consideradas um grupo de risco para complicações graves relacionadas ao vírus influenza H1N1, com grande morbidade e mortalidade observadas em epidemias anteriores do vírus Influenza. Quanto aos efeitos sobre o embrião-feto, os estudos a respeito do potencial teratogênico do vírus influenza ainda são limitados. A literatura não demonstrou, até o momento, efeitos adversos desse vírus sobre o embrião-feto. O tratamento específico consiste no uso de inibidores da neuraminidase, zanamivir e oseltamivir, dos quais apenas o último está disponível no Brasil. O objetivo geral da tese é avaliar as gestações expostas ao vírus H1N1 e submetidas ao tratamento com Fosfato de Oseltamivir. Os objetivos específicos são comparar gestantes expostas e não-expostas ao vírus Influenza A H1N1 quanto aos desfechos maternos e perinatais; avaliar os potenciais efeitos adversos da medicação em gestantes expostas ao oseltamivir; e avaliar a saúde e o desenvolvimento neuropsicomotor das crianças expostas durante a gravidez ao oseltamivir. Foi realizado um estudo de coorte prospectivo não controlado que avaliou gestantes com exposição ao vírus H1N1 e ao tratamento com Fosfato de Oseltamivir. A amostra consistiu nas 589 gestantes com sintomas suspeitos de Influenza A notificadas no Sistema de Informação de Agravos de Notificação - Influenza (SINAN-Influenza banco de dados do estado do Rio Grande do Sul). Os seguimentos de 424 gestantes foram realizados por contato telefônico, visita domiciliar, dados de prontuário médico ou Declaração de Nascido Vivo, por uma equipe treinada. . Foram obtidos 243 resultados de exames de PCR (polymerase chain reaction). Houve 163 (67%) casos confirmados de H1N1 e 80 (33%) Influenza não-H1N1. Houve 24 óbitos maternos, sendo 18 em H1N1. Houve 8 natimortos, sendo 5 filhos de gestantes expostas ao H1N1. Não houve diferença nos desfechos perinatais. Apenas um caso de malformação congênita (fenda palatina) foi observado em um bebe não exposto ao oseltamivir. Uso de oseltamivir foi identificado em 221 pacientes. Dessas, 86 gestantes apresentaram PCR positivo para Influenza A (H1N1) e 51 estavam no grupo não- H1N1. Reações adversas foram relatadas em 92 (42%) gestantes. Houve um maior número de reações adversas relatadas em pacientes não-H1N1 após o uso do oseltamivir. Ocorreram menos óbitos maternos (7,2%) nas que receberam oseltamivir comparativamente a 34,7% das mulheres que não foram tratadas (OR: 0,14, IC95%: 0,04-0,42, p=0,0003). Da mesma forma a frequência de natimortos foi menor (2,2%) nas tratadas, em comparação a 13,0% das não tratadas (OR: 0,15, IC95%: 0,03-0,89, p=0,03). Atrasos afetando dois ou mais marcos do desenvolvimento foram relatados em 10 (19,2%) de 52 crianças expostas ao oseltamivir durante o período gestacional e seguidas por no mínimo 36 meses. Essa frequência está acima do esperado para a população brasileira (15%). Em conclusão, espera-se que o presente trabalho seja capaz de contribuir para um melhor entendimento a respeito do potencial teratogênico do vírus Influenza A (H1N1) e de seu tratamento com o fármaco oseltamivir. Estudos futuros serão decisivos no estabelecimento de condutas clínicas no que diz respeito ao tratamento e manejo geral dessa condição nesse grupo específico de pacientes. / The present investigation approaches as central issue the outcomes of pregnancies exposed to the Influenza A (H1N1) virus and, consequently, to its treatment with the drug oseltamivir during the pandemic in the year 2009. The Influenza A H1N1 virus is the product of multiple genetic rearrangements among strains of influenza that had previously been circulating. Some of these were unique to swine and birds and became capable of infecting humans. The influenza A (H1N1) epidemic began in Mexico and rapidly spread to other countries around the world and was declared a pandemic by the World Health Organization (WHO) approximately two months after the first cases appeared. Pregnant women are considered to be a group at risk of serious complications related to the H1N1 influenza virus, with high morbidity and mortality observed in previous Influenza virus epidemics. As for effects on the embryo/fetus, there are still few studies on the teratogenic potential of the influenza virus. The literature has not demonstrated, so far, adverse effects of this virus on the embryo/fetus. The specific treatment is the use of the neuraminidase inhibitors, zanamivir and oseltamivir, of which only the latter is available in Brazil. The general aim of this work is to evaluate pregnancies exposed to the Influenza A (H1N1) virus and submitted to treatment with Oseltamivir Phosphate. Specific objectives are to compare pregnant women exposed and not exposed to the Influenza A H1N1 virus as on maternal and perinatal outcomes; evaluate potential adverse effects of medication in pregnant women exposed to oseltamivir; and evaluate the health and neurodevelopment in children exposed during pregnancy to oseltamivir. We performed an uncontrolled prospective cohort study that evaluated pregnancies with exposure to the H1N1 Influenza virus and its treatment with Oseltamivir Phosphate. The sample consisted of 589 pregnant women with suspected symptoms of Influenza A who were reported in the Information System for Notifiable Diseases - Influenza (SINAN-Influenza, Rio Grande do Sul Database). Follow-up of 424 pregnancies was conducted via telephone, home visit, medical records or Live Birth Certificate, by a trained team. PCR (polymerase chain reaction) was performed in 243 individuals. There were 163 (67%) confirmed cases of H1N1 and 80 (33%) non-H1N1 Influenza virus. There were twenty-four maternal deaths, 18 of these were H1N1+ patients. Eight stillbirths were reported, five of these were for H1N1+ pregnant women. There were no differences in perinatal outcomes. Only one cleft palate was reported in a newborn whose mother did not use oseltamivir. Use of oseltamivir phosphate was identified in 221 patients. Of this, there were 86 confirmed cases of Influenza A (H1N1) and 51 non-H1N1 Influenza virus. Adverse reactions were reported in 92 (42%) pregnancies. There were a higher number of adverse effects reported in non-H1N1 patients after the use of oseltamivir. There were fewer maternal deaths (7.2%) in those who received oseltamivir compared to 34.7% of women who were not treated (OR: 0.14, CI95%: 0.04-0.42, p=0.0003). Similarly, the frequency of stillbirth was lower (2.2%) in treated as compared to 13.0% of the untreated women (OR: 0.15, CI95%: 0.03- 0.89, p=0.03). Developmental delay in two or more skills was reported in 10 (19.2%) of 52 children exposed prenatally to oseltamivir and followed for at least 36 months. This rate is above of expected for the Brazilian population (15%). In conclusion, it is expected that this work can contribute to a better understanding towards the potential teratogenic effect of Influenza A (H1N1) virus and its treatment with oseltamivir. Future studies will be decisive to the establishment of clinical practices about treatment and general management of this condition in this specific group of patients.
14

Studies on Interspecies and Intraspecies Transmission of Influenza A Viruses

Yassine, Hadi M. 26 August 2009 (has links)
No description available.
15

Génération d'anticorps monoclonaux neutralisants et dérive antigénique du virus influenza pandémique A(H1N1) 2009

Retamal, Miguel 24 April 2018 (has links)
Encore aujourd'hui, la prévention de la grippe par la vaccination ou les approches thérapeutiques ne sont que partiellement efficaces. Les caractères d’hypervariabilité et de transmission du virus influenza lui permettent d’infecter les populations du monde entier malgré une immunité préexistante acquise par infection ou vaccination. En 2009 une éclosion de grippe A(H1N1) au Mexique s’est répandue mondialement et est devenue la pandémie A(H1N1)pdm09. Il devenait alors impératif d’étudier davantage ce virus influenza, notamment les sites antigéniques du virus qui sont les éléments clefs dans l’équilibre entre l’immunité des populations et la propagation du virus influenza. Pour étudier les sites antigéniques de la grippe A(H1N1)pdm09 et identifier leurs épitopes, leurs interactions et leurs immunodominances, nous avons créé des anticorps monoclonaux neutralisants (AcMoN) à l’aide de souris immunisées avec l’hémagglutinine recombinante du virus A(H1N1)pdm09. Les AcMoN obtenus ont été utilisés pour créer des mutants d’échappement in vitro. Nous avons ensuite introduit les mutations identifiées au sein des sites antigéniques de la HA1 par génétique inverse dans un virus réassortant (RG1) possédant six gènes du virus A/PR/8/34 (PA, PB1, PB2, M, NP et NS) et deux gènes (HA et NA) du virus pandémique A/Québec/144147/09. Ces virus ont été testés in vitro (par tests IHA et neutralisation) contre des sérums de furets immunisés contre le virus A(H1N1)pdm09 et in vivo (challenge infectieux ) chez des souris immunisées avec le vaccin influenza en vigueur au moment de l’étude puis infectées avec les virus mutants. D’autre part un AcMoN (appelé PN-SIA28) dirigé contre une portion conservée de la sous-unité HA2 responsable de la fusion du virus à la paroi cellulaire a également été testé quant à sa protection 24 heures post-infection sur des souris infectées avec les virus ; pandémique A/Québec/144147/09 (H1N1), A/WSN/33 (H1N1) et A/Victoria/3/75 (H3N2). Ces études ont permis d’obtenir 33 AcMoN qui ont conduit à l‘identification de 11 mutations d’intérêt immunologique, dont 6 au sein de sites antigéniques (T89R, G157E, G172E, N173D, K180E et A212E) et 5 en marge de ceux-ci (F128L, K180E, K256E, R269K, N311T et G478E). L’obtention de trois variants différents au sein du site antigénique ‘Sa’ adémontré l’immunodominance de celui-ci. Les mutations créées au sein des sites antigéniques sur des virus réassortants 6:2 ont démontré un grand potentiel de glissement antigénique. En effet, les souris immunisées avec la souche vaccinale sauvage n’ont pas été protégées suite aux infections par le virus muté aux sites antigéniques de la HA (RG1). L’AcMoN PN-SIA28 dirigé contre la région HA2 a quant à lui démontré une protection sur les souris infectées avec les virus issus des groupe phylogénétiques 1 (H1N1) et 2 (H3N2) de la HA. L’étude des sites antigéniques du virus A(H1N1) tel que menée dans ces travaux nous permet d’anticiper des mutations futures qui pourraient apparaître naturellement et causer des épidémies ne pouvant être freinées par le vaccin actuel protégeant contre la souche A/California/07/2009. De plus, la thérapie basée sur des AcMoN hétéro-sous-typiques dirigés contre des épitopes conservés ouvre une perspective thérapeutique qui complémente l’aspect préventif découlant de l’étude des sites antigéniques du virus influenza. / Presently, our ability to prevent influenza through vaccination or to remediate it therapeutically is still nowadays partially efficient. The hypervariability and the transmission aspects of influenza virus allow it to infect worldwide populations despite pre-existing immunity acquired through exposition or vaccination. In 2009, a new A(H1N1) virus in Mexico spread worldwide and became the A(H1N1)pdm09 pandemic virus. Since then, it was becoming imperative to study more deeply this influenza virus, especially its antigenic sites which are key elements in the equilibrium between population immunity and influenza virus propagation. In order to study the antigenic sites of flu A(H1N1)pdm09 and to identify their epitopes, their interactions and their immunodominances, we have generated neutralizing monoclonal antibodies (NMAbs) with mice immunized with recombinant hemagglutinin from A(H1N1)pdm09. The MAbs obtained were used for in vitro generation of escape mutants. Afterward, we introduced the identified mutations within the antigenic sites of the HA1 through reverse genetics in a reassortant virus (RG1) possessing six genes from virus A/PR/8/34 (PA, PB1, PB2, M, NP and NS) and two genes (HA and NA) from virus A/Quebec/144147/09. These viruses were tested in vitro (by HAI and neutralization) against sera of ferrets immunized with A(H1N1)pdm09 virus and in vivo (infectious challenge) in mice vaccinated with the current vaccine then infected with the mutant viruses. From another perspective, a MAb (named PN-SIA28) directed against a conserved portion of the HA2 subunit responsible for viral fusion to the host cell membrane, was tested for its protective properties 24 hour post-infection in mice infected with A/Quebec/144147/09 (H1N1) virus, A/WSN/33 (H1N1) virus and A/Victoria/3/75 (H3N2) virus. The study allowed us to obtain 33 MAbs and identify 11 mutations of immunological interest, from which 6 were inside antigenic sites (T89R, G157E, G172E, N173D, K180E and A212E), and 5 were outside them (F128L, K180E, K256E, N311T and G478E). The obtaining of three different variants for one single antigenic site ‘Sa’ demonstrates its immunodominance. The mutations created within the antigenic sites in reassortant 6:2 viruses could lead to high antigenic drift potential since mice immunized with the wild-type vaccine strain were not protected following infections with the RG1 virus having its HA antigenic sites mutated. PN-SIA28 MAb directed against the HA2 region showed protection of mice infected with viruses derived from HA phylogenetic groups 1 (H1N1) and 2 (H3N2). Our work, could allow to anticipate future antigenic drift which could appear naturally and cause epidemics not controlled by the actual vaccine directed towards A/California/07/09. Moreover, a therapy based on MAbs directed against conserved epitopes opens a therapeutic perspective that complements the preventive vaccine approach.
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Évaluation de l'impact de la mutation de résistance à l'oseltamivir (H275Y) sur les capacités réplicatives et la virulence du virus pandémique A(H1N1) pdm09

Pinilla, Lady Tatiana 19 April 2018 (has links)
Les inhibiteurs de neuraminidase (INAs) sont présentement la seule classe d’antiviral disponible commercialement pour traiter et prévenir les infections à virus influenza saisonnières et pandémiques. Le virus pandémique de 2009 était naturellement résistant aux adamantanes, mais sensible à l’oseltamivir et au zanamivir. Toutefois, plus de 1.5% de cas de résistance à l’oseltamivir ont été recensés suite à l’utilisation de l’antiviral en traitement ou en prophylaxie. La plupart d’entre eux possèdent une mutation ponctuelle (cytosine par thymidine) à la position 823, qui est à l’origine de la substitution d’une histidine par une tyrosine à la position 275 dans la séquence d'acides aminés de la neuraminidase (H275Y). Étant donné que le nombre d'antiviraux disponibles pour traiter et prévenir les infections à virus influenza est très limité (le zanamivir est le seul antiviral disponible commercialement pour traiter les souches pandémiques résistantes aux adamantanes et à l'oseltamivir), il est très important de comprendre les mécanismes qui causent la résistance aux INAs et d'établir un programme qui permet de surveiller l'évolution des souches résistantes aux antiviraux. / One class of anti-influenza agents; the neuraminidases inhibitors (NAIs), is the only choice commercially available for treatment and prophylaxis of seasonal and pandemic influenza infections. The pandemic 2009 Influenza virus, A(H1N1)pdm09, was naturally resistant to adamantanes but susceptible to the NAI: oseltamivir and zanamivir. However, more than 1.5% of cases of oseltamivir resistance have been reported during treatment and prophylaxis and most of them carried a single nucleotide mutation (cytosine to thymidine) at position 823 that resulted in a histidine to tyrosine mutation at position 275 in the neuraminidase sequence (H275Y). Considering that the number of available anti-influenza drugs is very restricted (zanamivir is now the only commercially available drug for treatment of the adamantane- and oseltamivir-resistant A(H1N1)pdm09 strains), it is important to understand mechanisms of resistance to NAIs and to perform a surveillance program for evolution of such drug-resistant variants.
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Épidémiologie des réactions d'allure allergique au vaccin contre la grippe pandémique A(H1N1)pdm09

Rouleau, Isabelle 20 April 2018 (has links)
À l’automne 2010, le Québec a réalisé une campagne de vaccination de masse contre la grippe pandémique A(H1N1) en utilisant presque exclusivement un nouveau vaccin adjuvanté à l’AS03 (Arepanrix, GlaxoSmithKline). Les données de surveillance recueillies durant la campagne de vaccination ont montré que le taux de déclaration d’anaphylaxie, une réaction systémique sévère souvent attribuable à l’allergie, s’est avéré être supérieur à celui historiquement observé avec les vaccins contre la grippe saisonnière (8 contre < 1 cas par million de doses, respectivement). De plus, l’évaluation systématique des déclarations de manifestations cliniques inhabituelles (MCI) d’allure allergique a démontré que l’anaphylaxie avait été sous-diagnostiquée parmi les cas déclarés. Plus du deux tiers des MCI d’allure allergique observées durant la campagne de vaccination contre la grippe pandémique sont survenues chez des femmes. En tenant compte du nombre de doses administrées, les femmes avaient un risque deux fois plus élevé que les hommes. De plus, ce risque était plus important durant les années de vie reproductive, soit entre l’âge de 20 et 49 ans. Notre étude cas-témoin appariée a identifié certains facteurs de risque dont l’histoire personnelle et familiale d’allergie, la présence d’une infection respiratoire et la prise de médicaments pour l’asthme dans les jours précédant la vaccination, le statut de travailleur de la santé, et une vaccination dans les 4 premières semaines de campagne. Toutefois, aucun de ces facteurs n’expliquait une grande partie des anaphylaxies ou des MCI d’allure allergique. La présence d’une allergie aux œufs ou au poisson, deux composantes potentiellement allergènes du vaccin, ne s’est pas avéré être un facteur de risque significatif de MCI d’allure allergique. Nous avons aussi réalisé une étude clinique en allergie auprès d’une centaine de cas déclarés durant la campagne de vaccination contre la grippe pandémique qui a montré que peu de ces événements pouvaient être attribuables à une allergie IgE-dépendante au vaccin ou à ses composantes. Cette recherche a mis en évidence le risque plus élevé d’anaphylaxie et de MCI d’allure allergique chez les femmes en âge reproducteur mais n’a pas réussi à identifier d’autres facteurs de risque majeurs. Elle a toutefois démontré que le mécanisme habituellement évoqué pour les expliquer soit la présence d’IgE ciblant une des composantes du vaccin semble jouer un rôle très mineur.
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Contribution à l'étude séro-épidémiologique de la grippe

Salez, Nicolas 15 January 2013 (has links)
Fin avril 2009, des cas de grippe causés par un nouveau virus grippal A/H1N1 d’origine porcine sont confirmés au Mexique et aux Etats-Unis. Rapidement, le virus est détecté aux quatre coins du globe causant la première pandémie du XXIème siècle. Les différents travaux présentés dans cette thèse retracent les moyens mis en œuvre pour obtenir des informations permettant d’estimer le taux d’attaque réel de ce nouveau virus et des informations sur les populations à risque. Durant les premiers mois, nous avons mis en place une plateforme de sérologies comprenant un laboratoire de réception et de traitement des échantillons pour l’exécution de notre technique d’IHA. Le traitement d’environ 40.000 sérums provenant de plusieurs endroits du globe : France, Bolivie, Djibouti, Mali, île de la Réunion et Laos a permis l’analyse de données sérologiques et leur comparaison. Nos études sérologiques de la grippe A(H1N1)pdm09 montrent que 10% à 40% des populations testées ont été infectées par ce nouveau virus après la première vague de 2009. Les plus forts taux d’attaque ont été observés chez les enfants et les jeunes adultes alors que les personnes âgées ont été relativement épargnées du fait qu’elles étaient déjà protégées contre des virus antigéniquements proches qui circulaient avant 1957 (virus pandémique et/ou saisonniers). L’analyse des données sérologiques ont également permis de tenter de définir les facteurs de risque à l’infection de A(H1N1)pdm09. / In late April 2009, news swine-origin A/H1N1 influenza virus cases were confirmed in Mexico and the United States. Quickly, it was spread worldwide causing the first flu pandemic of the 21st century. Different works presented in this thesis describe the means used to obtain information to estimate the actual attack rate of this new virus, and information on risk populations. During the first months, we have established a serology platform including a reception-processing samples laboratory for implementing our hémagglutination Inhibition technique (IHA). Processing of 40,000 sera from several parts of the world: France, Bolivia, Djibouti, Mali, Reunion and Laos, has allowed the analysis of serological data and their comparison. Our serological studies of influenza A(H1N1) pdm09 show that 10% to 40% of people tested were infected with this new virus after the first wave in 2009. The highest attack rates were observed in children and young adults, while the elderly were relatively spared because they were already protected again antigenic close viruses that circulated before 1957 (pandemic and / or seasonal). The analysis of serological data were also used to try to identify the risk factors for A(H1N1)pdm09 infection. It appears that infection with influenza A(H1N1)pdm09 was ubiquitous on the French territory, whatever the socio-demographic factors, and the Flu virus transmission can probably conditioned by the environmental and hygienic conditions in household.
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Att kommunicera med allmänheten i händelse av en pandemi : En fallstudie av ett landsting / Communicating with the public during a pandemic : A case study of a county council

Lundberg, Sandra January 2013 (has links)
I april 2009 upptäcktes en ny typ av influensa som senare fick namnet A(H1N1). Influensan A(H1N1) innebar en internationell kris och krävde särskilda krishanteringsåtgärder. I Sverige innebar detta att den största nationella massvaccineringen i modern tid genomfördes under hösten 2009 till och med början av 2010. Hanteringen ställde myndigheter, landsting och ansvariga individer inför en rad utmaningar, inte minst gällande planering och kommunikation. Syftet med studien var att studera erfarenheter av och planering inför kriskommunikation vid en pandemi utifrån erfarenheter och uppfattningar hos ansvariga aktörer inom ett landsting. Sju personer som arbetade på olika positioner vid ett landsting intervjuades. Studien har identifierat tre huvudområden. Hur de ansvariga aktörerna beskrev planeringen och kommunikationen vid pandemin, vilka svårigheter och utmaningar aktörerna upplevt i och med kriskommunikationen samt vilka lärdomar och implementeringar som gjorts utifrån ansvariga aktörers erfarenheter. Det framkom att hanteringen fungerade enligt de uppsatta planerna trots att det påpekades att dessa endast skulle ses som en vägledning. Vid hantering av pandemin stötte landstinget på en del svårigheter och utmaningar och för att hantera dessa krävdes ett flexibelt tillvägagångssätt. Efter pandemihanteringen har landstinget samlat på sig lärdomar och idéer om förbättringsområden. Vissa av dessa idéer är redan implementerade i landstingets dagliga arbete och andra är nedskrivna i diverse planverk. Det finns dock lärdomar och erfarenheter som inte är dokumenterade, i dessa fall finns det en risk att lärdomar och erfarenheter lämnar organisationen i och med att medarbetare byts ut. En slutsats var vikten av att alla erfarenheter dokumenteras för att viktig information ska föras vidare till nya medarbetare. / In April 2009 a new type of influenza was identified, which was named the A (H1N1). The influenza A (H1N1) resulted in an international crisis and called for specific management actions. In Sweden the largest national mass vaccination in modern times was conducted from autumn 2009 to early 2010. The crisis management posed authorities, county councils and responsible individuals to face a number of challenges, not to mention the current planning and communication. The purpose of this study was to study the experiences and planning for crisis communications during a pandemic based on experiences and perceptions of responsible actors within a county. Seven people who worked in various positions at the county were interviewed. The study has identified three main areas. How the responsible actors described the planning and communication in time of the pandemic, the difficulties and challenges experienced in the crisis communication by the actors and what lessons and implementations made by the responsible actors' experiences. It was revealed that the crisis management went according to the established plan, but it was also pointed out that the plans would only be seen as a guide. When handling the pandemic the County Council faced number of difficulties and challenges and to manage these a flexible approach was required. After the pandemic management the County Council has accumulated lessons and ideas on areas of improvement. Some of these ideas are already implemented in the daily work of the County Council and others are noted in various planning documents. However, there are lessons and experiences that are not documented, in these cases there is a risk that the lessons and experiences might leave the organization as employees are replaced. A conclusion was the importance that all experiences are documented so that important information will be passed on to new employees.
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Niños hospitalizados con neumonía por influenza AH1N11/2009 pandémico en un hospital de referencia de Perú.

Miranda-Choque, Edwin, Ramírez, Carlos, Candela-Herrera, Jorge, Díaz, Javier, Fernández, Ana, Kolevic, Lenka, Segura, Eddy R., Farfán-Ramos, Sonia 25 March 2014 (has links)
Objetivos. Determinar las características clínicas y demográficas de la neumonía por el virus de influenza AH1N1/2009 pandémico en un hospital de referencia de Perú. Materiales y métodos. Se realizó un estudio serie de casos en niños hospitalizados por neumonía por influenza AH1N1/2009 pandémico en un hospital de referencia. Revisamos las historias clínicas entre los meses de junio a septiembre 2009. Todos los casos tuvieron confirmación virológica. Resultados. Se encontró 74 casos de neumonía por el virus de Influenza AH1N1/2009 pandémico (NVIp), de los cuales 50 tuvieron el diagnóstico de neumonía adquirida en la comunidad viral (NACv) y 24 con neumonía nosocomial viral (NNv) de los cuales 16 requirieron ventilación mecánica. Fallecieron 12, todos ellos con antecedentes de comorbilidad. Los casos NNv presentaron asociación estadística con mortalidad. En los casos NACv, los menores de 6 años representaron 72 % (36/50). La mediana de tiempo de enfermedad fue de 5 días. Los síntomas más frecuentes fueron fiebre, tos, rinorrea. Recibieron oseltamivir el 82 %. En la radiografía de tórax el 48 % de los casos presentó infiltrado en parches y el 44 % infiltrado intersticial en la radiografía de tórax. La proteína C reactiva (PCR) mayor a 10mg/L tuvo una asociación significativa con insuficiencia respiratoria (p <0,05). Conclusiones. Encontramos casos NNv quienes tuvieron mayor mortalidad, también los que presentaron el PCR elevado y los que presentaron condición preexistente. / ObjectiveTo determine the clinical and demographic characteristics of pneumonia with influenza virus AH1N1/2009 pandemic at the National Institute of Child. Methods. Retrospective case series in children hospitalized for influenza pneumonia pandemic AH1N1/2009 in a pediatric hospital. Reviewed the medical records between the months of June to September 2009. All cases had virological confirmation, we describe the clinical characteristics and conditions of severity. Results. A total of 74 children of pneumonia with influenza virus AH1N1/2009 pandemic (NVIp), of those 50 were community acquire pneumonia viral (NACv) and 24 pneumonia nosocomial viral (NNv), 16 required mechanical ventilation. 12 died, all had preexisting factors. NN cases showed statistical association with mortality. The most frequent factors were malnutrition, respiratory infections, congenital heart disease and neurological deficits In NACv cases the children under 6 years accounted for 72% (36/50). The median disease duration was 5 days. The most frequent symptoms were fever, cough, runny nose. Received oseltamivir 82%. The chest radiograph 48% of cases showed patchy infiltrates and 44% interstitial infiltrate on chest radiograph. Protein c reactive (CRP) more than 10mg / L was significantly associated with respiratory failure (p <0.05). Conclusions. Cases of NN found who had more mortality, even those who had the highest PCR and those with preexisting condition.

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