Browsing by Author "Avila, Claudia"

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    Cross-species and mammal-to-mammal transmission of clade 2.3.4.4b highly pathogenic avian influenza A/H5N1 with PB2 adaptations
    (2025) Pardo Roa, Catalina; Nelson, Martha I.; Ariyama, Naomi; Aguayo, Carolina; Almonacid Cárdenas, Leonardo Iván; Gonzalez-Reiche, Ana S.; Muñoz, Gabriela; Ulloa, Mauricio; Avila, Claudia; Navarro, Carlos; Reyes, Rodolfo; Castillo Torres, Pablo Nicolás; Mathieu, Christian; Vergara, Ricardo; Gonzalez, Alvaro; Gonzalez, Carmen Gloria; Araya, Hugo; Castillo, Andres; Torres, Juan Carlos; Covarrubias, Paulo; Bustos, Patricia; van Bakel, Harm; Fernandez, Jorge; Fasce, Rodrigo A.; Johow, Magdalena; Neira, Victor; Medina, Rafael
    Highly pathogenic H5N1 avian influenza viruses (HPAIV) belonging to lineage 2.3.4.4b emerged in Chile in December 2022, leading to mass mortality events in wild birds, poultry, and marine mammals and one human case. We detected HPAIV in 7,33% (714/9745) of cases between December 2022-April 2023 and sequenced 177 H5N1 virus genomes from poultry, marine mammals, a human, and wild birds spanning >3800 km of Chilean coastline. Chilean viruses were closely related to Peru's H5N1 outbreak, consistent with north-to-south spread down the Pacific coastline. One human virus and nine marine mammal viruses in Chile had the rare PB2 D701N mammalian-adaptation mutation and clustered phylogenetically despite being sampled 5 weeks and hundreds of kilometers apart. These viruses shared additional genetic signatures, including another mammalian PB2 adaptation (Q591K, n = 6), synonymous mutations, and minor variants. Several mutations were detected months later in sealions in the Atlantic coast, indicating that the pinniped outbreaks on the west and east coasts of South America are genetically linked. These data support sustained mammal-to-mammal transmission of HPAIV in marine mammals over thousands of kilometers of Chile's Pacific coastline, which subsequently continued through the Atlantic coastline.
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    Cross-species and mammal-to-mammal transmission of clade 2.3.4.4b highly pathogenic avian influenza A/H5N1 with PB2 adaptations
    (2025) Pardo Roa, Catalina; Nelson, Martha I.; Ariyama, Naomi; Aguayo, Carolina; Almonacid Cárdenas, Leonardo Iván; Gonzalez-Reiche, Ana S.; Muñoz, Gabriela; Ulloa, Mauricio; Avila, Claudia; Navarro, Carlos; Reyes, Rodolfo; Castillo Torres, Pablo Nicolás; Mathieu, Christian; Vergara, Ricardo; Gonzalez, Alvaro; Gonzalez, Carmen Gloria; Araya, Hugo; Castillo, Andres; Torres, Juan Carlos; Covarrubias, Paulo; Bustos, Patricia; van Bakel, Harm; Fernandez, Jorge; Fasce, Rodrigo A.; Johow, Magdalena; Neira, Victor; Medina, Rafael
    Highly pathogenic H5N1 avian influenza viruses (HPAIV) belonging to lineage 2.3.4.4b emerged in Chile in December 2022, leading to mass mortality events in wild birds, poultry, and marine mammals and one human case. We detected HPAIV in 7,33% (714/9745) of cases between December 2022-April 2023 and sequenced 177 H5N1 virus genomes from poultry, marine mammals, a human, and wild birds spanning >3800 km of Chilean coastline. Chilean viruses were closely related to Peru's H5N1 outbreak, consistent with north-to-south spread down the Pacific coastline. One human virus and nine marine mammal viruses in Chile had the rare PB2 D701N mammalian-adaptation mutation and clustered phylogenetically despite being sampled 5 weeks and hundreds of kilometers apart. These viruses shared additional genetic signatures, including another mammalian PB2 adaptation (Q591K, n = 6), synonymous mutations, and minor variants. Several mutations were detected months later in sealions in the Atlantic coast, indicating that the pinniped outbreaks on the west and east coasts of South America are genetically linked. These data support sustained mammal-to-mammal transmission of HPAIV in marine mammals over thousands of kilometers of Chile's Pacific coastline, which subsequently continued through the Atlantic coastline.
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    Emergence and rapid dissemination of highly pathogenic avian influenza virus H5N1 clade 2.3.4.4b in wild birds, Chile.
    (SPRINGER INTERNATIONAL PUBLISHING AG, 2023) Ariyama, Naomi; Pardo-Roa, Catalina; Munoz, Gabriela; Aguayo, Carolina; Avila, Claudia; Mathieu, Christian; Brito, Barbara; Medina, Rafael; Johow, Magdalena; Neira, Victor
    In December 2022, HPAI H5N1 clade 2.3.4.4b emerged in Chile. We detected the virus in 93 wild bird samples and sequenced the whole genome of nine Chilean strains from pelicans and gulls. Phylogenetic analysis suggests at least two different HPAI viral clusters in South America.
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    First report and genetic characterization of Seneca Valley virus (SVV) in Chile
    (SPRINGER INTERNATIONAL PUBLISHING AG, 2022) Bennett, Benjamin; Urzua-Encina, Constanza; Pardo-Roa, Catalina; Ariyama, Naomi; Lecocq, Claudio; Rivera, Carlos; Badia, Catalina; Suarez, Paulina; Agredo, Michel; Aguayo, Carolina; Avila, Claudia; Araya, Hugo; Perez, Patricio; Berrios, Felipe; Aguero, Belen; Mendieta, Vanessa; Pituco, Edviges Maristela; de Almeida, Iassudara Garcia; Medina, Rafael; Brito, Barbara; Johow, Magdalena; Neira Ramirez, Victor
    Seneca Valley virus (SVV) is a non-enveloped RNA virus and the only member of the Senecavirus A (SVA) species, in the Senecavirus genus, Picornaviridae family. SVV infection causes vesicular lesions in the oral cavity, snout and hooves of pigs. This infection is clinically indistinguishable from trade-restrictions-related diseases such as foot-and-mouth disease. Other clinical manifestations include diarrhoea, anorexia, lethargy, neurological signs and mortality in piglets during their first week of age. Before this study, Chile was considered free of vesicular diseases of swine, including SVV. In April 2022, a suspected case of vesicular disease in a swine farm was reported in Chile. The SVV was confirmed and other vesicular diseases were ruled out. An epidemiological investigation and phylogenetic analyses were performed to identify the origin and extent of the outbreak. Three hundred ninety-five samples from 44 swine farms were collected, including faeces (208), oral fluid (28), processing fluid (14), fresh semen (61), environmental samples (80) and tissue from lesions (4) for real-time RT-PCR detection. Until June 2022, the SVV has been detected in 16 out of 44 farms, all epidemiologically related to the index farm. The closest phylogenetic relationship of the Chilean SVV strain is with viruses collected from swine in California in 2017. The direct cause of the SVV introduction has not yet been identified; however, the phylogenetic analyses suggest the USA as the most likely source. Since the virus remains active in the environment, transmission by fomites such as contaminated feed cannot be discarded. Further studies are needed to determine the risk of the introduction of novel SVV and other transboundary swine pathogens to Chile.
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    Mode of delivery and antenatal steroids and their association with survival and severe intraventricular hemorrhage in very low birth weight infants
    (2016) Hubner, M. E.; Ramirez, R.; Burgos, J.; Dominguez, A.; Tapia, J. L.; Colantonio, Guillermo; Zapata, Jorge; Perez, Gaston; Ana Pedraza, Susana Garcia; Kurlat, Isabel; Di Siervi, Oscar; Escarate, Adriana; Mariani, Gonzalo; Maria Ceriani, Jose; Fernandez, Silvia; Fustinana, Carlos; Brener, Pablo; Edwards, Eleonora; Tavosnaska, Jorge; Roldan, Liliana; Sexer, Hector; Saa, Gladys; Sabatelli, Debora; Laura Gendra, Maria; Fernanda Buraschi, Maria; Molina, Paula; Daniel, Agost; Morganti, Federico; Fontana, Adriana; Chandias, Daniela; Rinaldi, Monica; Grandi, Carlos; Rojas, Elio; Solana, Claudio; Nieto, Ricardo; Meritano, Javier; Larguia, Miguel; Kasten, Laura; Cuneo, Lucrecia; Decaro, Marcelo; Cracco, Lionel; Bassi, Gustavo; Jacobi, Noemi; Brum, Andrea; Vain, Nestor; Aguilar, Adriana; Guerrero, Miriam; Szyld, Edgardo; Escandar, Alcira; Abdala, Daniel; Guida, Martin; Ferrin, Lucila; Roge, Horacio; Musante, Gabriel; Capelli, Maria C.; Pablo Berazategui, Juan; de Elizalde, Magdalena; Ignacio Fraga, Juan; Keller, Rodolfo; Ahumada, Luis; Ferreyra, Mirta; Ferreira, Vanda; Borges, Roberta; Do Vale, Marynea; Cavalcante, Silvia; Gusmao, Joama; Franco, Patricia; Jose Silva, Maria; Fabres, Jorge; Estay, Alberto; Gonzalez, Alvaro; Kattan, Javier; Quezada, Mariela; Urzua, Soledad; Campos, Lilia; Cifuentes, Lilian; Leon, Jorge; Aguilar, Roxana; Treuer, Sergio; Giaconi, Jimena; Bancalari, Aldo; Standen, Jane; Escobar, Marisol; Veas, Viviana; Sandino, Daniela; Gonzalez, Agustina; Avila, Claudia; Guzman, Carla; Toro, Claudia; Mena, Patricia; Milet, Beatriz; Pittaluga, Enrica; Pena, Veronica; Mendizabal, Rafael; Pizarro, Dagoberto; D'Apremont, Ivonne; Tapia, Jose L.; Marshall, Guillermo; Villarroel, Luis; Quezada, Mariela; Dominguez, Angelica; Lacarruba, Jose; Cespedes, Elizabeth; Mir, Ramon; Mendieta, Elvira; Genes, Larissa; Caballero, Carlos; Webb, Veronica; Rivera, Fabiola; Llontop, Margarita; Bellomo, Sicilia; Zegarra, Jaime; Chumbes, Oscar; Castaneda, Anne; Cabrera, Walter; Llanos, Raul; Mucha, Jorge; Garcia, Gustavo; Ceruti, Beatriz; Borbonet, Daniel; Gugliucci, Sandra; Lain, Ana; Martinez, Mariza; Bazan, Gabriela; Piffaretti, Susana; Cuna, Isabel; Bermudez, Patricia
    OBJECTIVE: To determine whether CS delivery and receipt of antenatal steroids (ANS) in vertex-presenting singletons with a gestational age (GA) between 24 and 30 weeks is associated with improved survival and improved severe intraventricular hemorrhage (sIVH)-free survival.