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1.
Viruses ; 15(7)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37515267

RESUMO

The avian infectious bronchitis virus (IBV) is a coronavirus that mutates frequently, leading to a contagious and acute disease that results in economic losses to the global poultry industry. Due to its genetic and serological diversity, IBV poses a challenge in preventing and controlling the pathogen. The full-length S1 sequence analysis identifies seven main genotypes (GI-GVII) comprising 35 viral lineages. In addition to the previously described lineage, a new GI lineage (GI-30) and two lineages from novel genotypes (GVIII-1 and GIX-1) have been described in Mexico. To prevent the spread of IBV outbreaks in a specific geographic location and select the suitable vaccine, it is helpful to genetically identify the circulating IBV types. Moreover, sequencing genomes can provide essential insights into virus evolution and significantly enhance our understanding of IBV variability. However, only genomes of previously described lineages (GI-1, GI-9, GI-13, and GI-17) have been reported for Mexican strains. Here, we sequenced new genomes from Mexican lineages, including the indigenous GI-30, GVIII-1, and GIX-1 lineages. Comparative genomics reveals that Mexico has relatively homogenous lineages (i.e., GI-13), some with greater variability (i.e., GI-1 and GI-9), and others extremely divergent (GI-30, GVIII-1, and GIX-1). The circulating lineages and intra-lineage variability support the unique diversity and dynamic of Mexican IBV.


Assuntos
Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Animais , Vírus da Bronquite Infecciosa/genética , México/epidemiologia , Galinhas , Genótipo , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Recombinação Genética , Doenças das Aves Domésticas/epidemiologia , Filogenia
2.
Poult Sci ; 101(10): 102076, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36041394

RESUMO

The avian infectious bronchitis virus (IBV) is a highly mutable coronavirus that causes an acute and highly contagious disease responsible for economic losses to the poultry industry worldwide. Preventing and controlling bronchitis disease is difficulted by the numerous IBV circulating types with limited antigenic cross-protection that hamper the prevention and control by heterologous vaccines. The coding region of the variable spike S1 receptor-attachment domain is used to classify IBV in 7 genotypes (GI-GVII) comprising 35 viral lineages (1-35). Knowledge of the circulating IBV types causing outbreaks in a specific geographic region is beneficial to select better the appropriate vaccine(s) and contribute to disease control. In the study, 17 avian infectious bronchitis virus strains were obtained from chickens showing signs of illness in Mexico from 2007 to 2021. We detected 4 lineages within genotype I, three already known (GI-3, GI-9, GI-13) and one newly described (GI-30). In addition, we identified 2 divergent monophyletic groups that are tentatively described as lineages of new genotypes (GVIII-1 and GIX-1). Our findings revealed that Mexico's high genetic IBV diversity results from the co-circulation of divergent lineages belonging to different genotypes. Mexican IBV lineages differ significantly from Massachusetts and Connecticut vaccine strains, indicating that the currently used vaccines may need to be updated.


Assuntos
Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Vacinas Virais , Animais , Galinhas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Variação Genética , Vírus da Bronquite Infecciosa/genética , México/epidemiologia , Doenças das Aves Domésticas/prevenção & controle
3.
Arch Virol ; 167(11): 2109-2121, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35794491

RESUMO

Canine parvovirus type 2 (CPV-2) infection in dogs is associated with severe gastroenteritis, bloody diarrhea, and vomiting, resulting in high rates of death, especially in unvaccinated puppies within the first months of age. There are three variants, called CPV-2a, CPV-2b, and CPV-2c, co-circulating worldwide. Our group previously reported that the only circulating CPV-2 variant in the Guadalajara metropolitan area in western Mexico was type 2c. Now, a five-year study was performed in order to investigate the possible dominance of CPV-2c in our region. Rectal swabs were collected from 146 dogs with clinical gastroenteritis from May 2014 to August 2019 at the Veterinary Hospital of the University of Guadalajara. Of these, 90 dogs tested positive for canine parvovirus by PCR. Most of the infected dogs with CPV-2 had a partial or incomplete vaccination status (n = 88, 97.8%). Approximately 65% (n = 59) of them were mixed-breed dogs, 77.8% (n = 70) were under 6 months of age, and 37.8% (n = 34) of them died from clinical complications. RFLP analysis of amplicons derived from the vp2 gene showed that all 90 DNA samples corresponded to CPV-2c, with no evidence of the presence of CPV-2a or CPV-2b variants. Twenty-nine of the 90 DNA samples were selected for amplification of a portion of the vp2 gene, and sequencing of these amplicons showed that all of them had the sequence GAA at codon 426, encoding the amino acid glutamic acid, which is characteristic of CPV-2c. Phylogenetic analysis showed that the CPV-2c sequences were related to those of viruses from Europe and South America. The present study indicates that CPV-2c is still the only variant circulating in the dog population of the Guadalajara metropolitan area.


Assuntos
Doenças do Cão , Gastroenterite , Infecções por Parvoviridae , Parvovirus Canino , Animais , Códon , Doenças do Cão/epidemiologia , Cães , Gastroenterite/epidemiologia , Gastroenterite/genética , Gastroenterite/veterinária , Ácido Glutâmico/genética , México/epidemiologia , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/genética , Filogenia , Melhoramento Vegetal
4.
Ann Hepatol ; 18(4): 571-577, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31080055

RESUMO

INTRODUCTION AND OBJECTIVES: To characterize the virological features of hepatitis E virus (HEV) in serum from patients exhibiting chronic liver damage. METHODS: A data-base of 513 unrelated individuals from West-Mexico with liver-disease determined by clinical and biochemical tests and transient elastography between 2011 and 2016 were retrospectively analyzed. According to infectious etiologies, patients were classified as hepatitis B virus (HBV)-, hepatitis C virus (HCV)-infected patients, and patients exhibiting chronic liver damage with non-identified infectious etiological agent (NIIEA). Available serum samples from NIIEA-patients were tested by RT-nPCR for the presence of HEV-RNA and partially sequenced for genotyping. RESULTS: Out of the 513 cases, 5.85% were patients infected with HBV, 67.64% with HCV, and 26.51% were NIIEA-patients. Among 76 available samples from NIIEA-cases, 30.26% tested positive for HEV-RNA. Twelve (15.79%) partial HEV sequences allowed phylogenetic analysis, revealing the classification of HEV as HEV-Gt3. Advanced fibrosis (F3-F4 stage) was found in a 26.1% of patients with HEV-active infection. CONCLUSION: Although HCV is the main infectious agent related to chronic liver disease in Mexico, liver damage without an infectious etiology is common. Our findings reveal that an elevated rate of chronic liver disease might be represented by autochthonous infection of HEV-Gt3, whose detection makes Mexico unique in Latin-America with the circulation of HEV strains belonging to three genotypes (Gt1, Gt2, and Gt3). Thus, HEV infection should be a matter of health concern, and mandates for HEV screening to properly handle this commonly undiagnosed disease.


Assuntos
Vírus da Hepatite E/genética , Hepatite E/epidemiologia , Cirrose Hepática/virologia , RNA Viral/sangue , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Doença Crônica , Técnicas de Imagem por Elasticidade , Feminino , Genótipo , Hepatite E/sangue , Hepatite E/diagnóstico , Hepatite E/virologia , Humanos , L-Lactato Desidrogenase/sangue , Cirrose Hepática/sangue , Hepatopatias/sangue , Hepatopatias/virologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Contagem de Plaquetas , Reação em Cadeia da Polimerase , RNA Viral/análise , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , gama-Glutamiltransferase/sangue
5.
Intervirology ; 61(3): 105-110, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30278455

RESUMO

OBJECTIVE: We aimed to detect and characterize hepatitis E virus (HEV) RNA in sera samples from a pediatric population infected with the hepatitis A virus (HAV) exhibiting acute hepatitis and to correlate the infection status with the clinical outcome. METHODS: Seventy-five ELISA-positive samples from children containing anti-HAV and anti-HEV IgM were used to amplify and characterize partial regions within HEV ORF2. A statistical comparison of clinical data between HEV IgM-positive/HEV RNA-positive patients and HEV IgM-positive/HEV RNA-negative patients was performed. RESULTS: Thirteen out of 75 IgM-positive samples provided amplification of discrete regions of the HEV genome. Nested RT-PCR-based detection and subsequent sequencing of 5 samples confirmed the identity of HEV genotype 1 (G1), which had not been previously reported in Mexico. Though not significant, a trend towards exacerbated clinical manifestations was found in HEV RNA-positive patients relative to HEV RNA-negative patients. CONCLUSIONS: An elevated rate of G1 RNA was detected. Hepatitis E seems to be a neglected disease in Mexico and epidemic strains of HEV are likely to play a role as causative agents of acute hepatitis in highly exposed children. Although HAV is endemic in Mexico, an HEV-RNA detection rate of 17% in co-infected samples shows the need for screening for HEV as a part of future vaccination strategies.


Assuntos
Coinfecção/epidemiologia , Coinfecção/virologia , Hepatite A/epidemiologia , Hepatite E/epidemiologia , Adolescente , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Vírus da Hepatite A/genética , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/genética , Humanos , Imunoglobulina M/sangue , Lactente , Masculino , México/epidemiologia , Pobreza/estatística & dados numéricos , RNA Viral/sangue , Classe Social
6.
PeerJ ; 6: e5482, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30155367

RESUMO

Salmonella is one of the major foodborne pathogens worldwide. The antimicrobial resistance (AMR) of this foodborne pathogen has raised a great concern in recent years. Studies on the frequency and characterization of Salmonella serotypes can help to improve our knowledge on the epidemiology of this pathogen. The purpose of this study was to compare the serotypes, AMR and genetic profiles of Salmonella isolates recovered from raw beef throughout the beef production chain and from human feces associated with clinical cases of salmonellosis. The serotype, AMR and pulsed-field gel electrophoresis profile of 243 Salmonella enterica isolates recovered from beef carcasses (n = 78), ground beef (n = 135), and human feces from clinical cases of salmonellosis (n = 30) were compared. Forty-three different Salmonella serotypes were identified and regardless of the source, the top five corresponded to Typhimurium, Give, Group B (partially serotyped), Infantis and Anatum. Twelve serotypes from beef carcasses were also found in ground beef, showing their presence throughout the beef production chain. Salmonella Typhimurium, Infantis, Anatum and Montevideo were the only serotypes identified in all sample types. Resistance to tetracyclines was the most frequent (41.2%) followed by resistance to aminoglycosides (37%), folate pathway inhibitors (21%), quinolones (20.2%), phenicols (17.1%), penicillins (15.6%) and cephems (7%). Multidrug resistance was observed in 28.8% of the isolates, and those from human feces showed resistance to a larger number of antimicrobials. Great concern arises from the resistance and reduced susceptibility observed to quinolones and cephalosporins because these drugs are the first line of treatment for invasive Salmonella infections. Twenty-seven distinct pulse-types were detected among 238 isolates. Clustering analysis for the most frequent serotypes identified groups of isolates with similar AMR profiles. Multidrug resistance spreading throughout the food production chain should be continually monitored and its importance emphasized.

7.
Ann Hepatol ; 17(4): 544-546, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29893694

RESUMO

Based on high seroprevalence, null surveillance, and lack of diagnostics, Mexico is a high-risk region for hepatitis E Virus (HEV) infection. However, few local news on infection are available. Clinicians and general population are in need of increasing awareness, and preventive measures should be emphasized.


Assuntos
Vírus da Hepatite E/patogenicidade , Hepatite E/virologia , Zoonoses/virologia , Animais , Genótipo , Hepatite E/epidemiologia , Hepatite E/terapia , Hepatite E/transmissão , Vírus da Hepatite E/genética , Humanos , México/epidemiologia , Prognóstico , Medição de Risco , Fatores de Risco , Zoonoses/epidemiologia , Zoonoses/terapia , Zoonoses/transmissão
8.
Artigo em Inglês | PAHO-IRIS | ID: phr-34971

RESUMO

[ABSTRACT]. The symposium “Epidemiology of Hepatitis E virus (HEV) Infection and Associated Immune Response” was held at the Universidad de Guadalajara, Mexico, on 14 June 2017, to define the status of research on HEV infection in three countries in Latin America and the Caribbean (LAC)—Cuba, Mexico, and Uruguay—compared to the situation in Germany. Scientists identified specific research gaps in understanding HEV transmission and the resulting impact on development of disease in the three abovementioned LAC countries. Specific recommendations for implementing standardized serologic and molecular diagnostic methods and epidemiologic, basic, and applied research aimed to develop prevention and handling strategies for this infection, along with the associated comorbidities in the three LAC countries, were also discussed. Given similar demographic, sanitary, and economic conditions in other LAC countries that could predispose them to be at high risk for HEV transmission and infection, these research gaps and recommendations might apply to the entire LAC region. This report was prepared by meeting participants based on 1) symposium presentations, 2) literature reviews, and 3) group discussions.


[RESUMEN]. El 14 de junio del 2017 se realizó en la Universidad de Guadalajara (México) un simposio sobre las características epidemiológicas de la infección por el virus de la hepatitis E (VHE) y la respuesta inmunitaria asociada. El objetivo fue definir el estado de las investigaciones sobre la infección por el VHE en tres países de América Latina y el Caribe —Cuba, México y Uruguay— en comparación con la situación en Alemania. Los científicos señalaron que para comprender la transmisión del VHE y la consiguiente repercusión en el avance de la infección en estos tres países latinoamericanos aún faltan investigaciones sobre ciertos temas específicos. También analizaron recomendaciones concretas para poner en práctica métodos estandarizados de diagnóstico serológico y molecular, y realizar investigaciones epidemiológicas, básicas y aplicadas a fin de elaborar estrategias de prevención y tratamiento de esta infección y las comorbilidades asociadas en los tres países antes mencionados. Considerando que otros países de América Latina y el Caribe presentan condiciones demográficas, sanitarias y económicas similares que podrían implicar una predisposición a un riesgo alto de transmisión del VHE y de infección por este virus, este análisis sobre las brechas y recomendaciones en el ámbito de la investigación podría aplicarse en toda la subregión. El presente informe fue elaborado por los participantes del simposio sobre la base de: 1) presentaciones del simposio; 2) revisiones bibliográficas; y 3) debates en grupos.


[RESUMO]. O simpósio Epidemiologia da infecção pelo vírus da hepatite E (HEV) e resposta imune associada foi realizado na Universidade de Guadalajara, no México, em 14 de junho de 2017, para determinar a situação da pesquisa em HEV em três países da América Latina e Caribe (ALC) – Cuba, México e Uruguai – em comparação à Alemanha. Os especialistas identificaram lacunas específicas nas pesquisas no que se refere ao entendimento da transmissão do HEV e ao impacto resultante do surgimento da doença nos três países da ALC mencionados. Também foram debatidas recomendações aos três países da ALC, especificamente implementar métodos sorológicos e moleculares padronizados de diagnóstico e realizar pesquisa epidemiológica, básica e aplicada visando elaborar estratégias de prevenção e de enfrentamento da infecção e das comorbidades associadas. Diante da semelhança das condições demográficas, econômicas e de saúde que poderia predispor outros países da ALC a um maior risco de transmissão e infecção de HEV, as lacunas em pesquisa e recomendações provavelmente se aplicam à toda a Região da ALC. Este relatório foi preparado pelos participantes do encontro embasado nas apresentações do simpósio, revisão da literatura científica e discussões em grupo.


Assuntos
Vírus da Hepatite E , Cuba , México , Uruguai , América Latina , Região do Caribe , América Latina , Região do Caribe , Vírus da Hepatite E , Vírus da Hepatite E , Região do Caribe
9.
Rev Panam Salud Publica ; 42: e41, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31093069

RESUMO

The symposium "Epidemiology of Hepatitis E virus (HEV) Infection and Associated Immune Response" was held at the Universidad de Guadalajara, Mexico, on 14 June 2017, to define the status of research on HEV infection in three countries in Latin America and the Caribbean (LAC)-Cuba, Mexico, and Uruguay-compared to the situation in Germany. Scientists identified specific research gaps in understanding HEV transmission and the resulting impact on development of disease in the three abovementioned LAC countries. Specific recommendations for implementing standardized serologic and molecular diagnostic methods and epidemiologic, basic, and applied research aimed to develop prevention and handling strategies for this infection, along with the associated comorbidities in the three LAC countries, were also discussed. Given similar demographic, sanitary, and economic conditions in other LAC countries that could predispose them to be at high risk for HEV transmission and infection, these research gaps and recommendations might apply to the entire LAC region. This report was -prepared by meeting participants based on 1) symposium presentations, 2) literature reviews, and 3) group discussions.


El 14 de junio del 2017 se realizó en la Universidad de Guadalajara (México) un simposio sobre las características epidemiológicas de la infección por el virus de la hepatitis E (VHE) y la respuesta inmunitaria asociada. El objetivo fue definir el estado de las investigaciones sobre la infección por el VHE en tres países de América Latina y el Caribe ­Cuba, México y Uruguay­ en comparación con la situación en Alemania. Los científicos señalaron que para comprender la transmisión del VHE y la consiguiente repercusión en el avance de la infección en estos tres países latinoamericanos aún faltan investigaciones sobre ciertos temas específicos. También analizaron recomendaciones concretas para poner en práctica métodos estandarizados de diagnóstico serológico y molecular, y realizar investigaciones epidemiológicas, básicas y aplicadas a fin de elaborar estrategias de prevención y tratamiento de esta infección y las comorbilidades asociadas en los tres países antes mencionados. Considerando que otros países de América Latina y el Caribe presentan condiciones demográficas, sanitarias y económicas similares que podrían implicar una predisposición a un riesgo alto de transmisión del VHE y de infección por este virus, este análisis sobre las brechas y recomendaciones en el ámbito de la investigación podría aplicarse en toda la subregión. El presente informe fue elaborado por los participantes del simposio sobre la base de: 1) presentaciones del simposio; 2) revisiones bibliográficas; y 3) debates en grupos.


O simpósio Epidemiologia da infecção pelo vírus da hepatite E (HEV) e ­resposta imune associada foi realizado na Universidade de Guadalajara, no México, em 14 de junho de 2017, para determinar a situação da pesquisa em HEV em três países da América Latina e Caribe (ALC) ­ Cuba, México e Uruguai ­ em comparação à Alemanha. Os especialistas identificaram lacunas específicas nas pesquisas no que se refere ao entendimento da transmissão do HEV e ao impacto resultante do surgimento da doença nos três países da ALC mencionados. Também foram debatidas recomendações aos três países da ALC, especificamente implementar métodos sorológicos e moleculares padronizados de diagnóstico e realizar pesquisa epidemiológica, básica e aplicada visando elaborar estratégias de prevenção e de enfrentamento da infecção e das comorbidades associadas. Diante da semelhança das condições demográficas, econômicas e de saúde que poderia predispor outros países da ALC a um maior risco de transmissão e infecção de HEV, as lacunas em pesquisa e recomendações provavelmente se aplicam à toda a Região da ALC. Este relatório foi preparado pelos participantes do encontro embasado nas apresentações do simpósio, revisão da literatura científica e discussões em grupo.

10.
Rev. panam. salud pública ; 42: e41, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-961739

RESUMO

ABSTRACT The symposium "Epidemiology of Hepatitis E virus (HEV) Infection and Associated Immune Response" was held at the Universidad de Guadalajara, Mexico, on 14 June 2017, to define the status of research on HEV infection in three countries in Latin America and the Caribbean (LAC)—Cuba, Mexico, and Uruguay—compared to the situation in Germany. Scientists identified specific research gaps in understanding HEV transmission and the resulting impact on development of disease in the three abovementioned LAC countries. Specific recommendations for implementing standardized serologic and molecular diagnostic methods and epidemiologic, basic, and applied research aimed to develop prevention and handling strategies for this infection, along with the associated comorbidities in the three LAC countries, were also discussed. Given similar demographic, sanitary, and economic conditions in other LAC countries that could predispose them to be at high risk for HEV transmission and infection, these research gaps and recommendations might apply to the entire LAC region. This report was ­prepared by meeting participants based on 1) symposium presentations, 2) literature reviews, and 3) group discussions.


RESUMEN El 14 de junio del 2017 se realizó en la Universidad de Guadalajara (México) un simposio sobre las características epidemiológicas de la infección por el virus de la hepatitis E (VHE) y la respuesta inmunitaria asociada. El objetivo fue definir el estado de las investigaciones sobre la infección por el VHE en tres países de América Latina y el Caribe —Cuba, México y Uruguay— en comparación con la situación en Alemania. Los científicos señalaron que para comprender la transmisión del VHE y la consiguiente repercusión en el avance de la infección en estos tres países latinoamericanos aún faltan investigaciones sobre ciertos temas específicos. También analizaron recomendaciones concretas para poner en práctica métodos estandarizados de diagnóstico serológico y molecular, y realizar investigaciones epidemiológicas, básicas y aplicadas a fin de elaborar estrategias de prevención y tratamiento de esta infección y las comorbilidades asociadas en los tres países antes mencionados. Considerando que otros países de América Latina y el Caribe presentan condiciones demográficas, sanitarias y económicas similares que podrían implicar una predisposición a un riesgo alto de transmisión del VHE y de infección por este virus, este análisis sobre las brechas y recomendaciones en el ámbito de la investigación podría aplicarse en toda la subregión. El presente informe fue elaborado por los participantes del simposio sobre la base de: 1) presentaciones del simposio; 2) revisiones bibliográficas; y 3) debates en grupos.


RESUMO O simpósio Epidemiologia da infecção pelo vírus da hepatite E (HEV) e ­resposta imune associada foi realizado na Universidade de Guadalajara, no México, em 14 de junho de 2017, para determinar a situação da pesquisa em HEV em três países da América Latina e Caribe (ALC) - Cuba, México e Uruguai - em comparação à Alemanha. Os especialistas identificaram lacunas específicas nas pesquisas no que se refere ao entendimento da transmissão do HEV e ao impacto resultante do surgimento da doença nos três países da ALC mencionados. Também foram debatidas recomendações aos três países da ALC, especificamente implementar métodos sorológicos e moleculares padronizados de diagnóstico e realizar pesquisa epidemiológica, básica e aplicada visando elaborar estratégias de prevenção e de enfrentamento da infecção e das comorbidades associadas. Diante da semelhança das condições demográficas, econômicas e de saúde que poderia predispor outros países da ALC a um maior risco de transmissão e infecção de HEV, as lacunas em pesquisa e recomendações provavelmente se aplicam à toda a Região da ALC. Este relatório foi preparado pelos participantes do encontro embasado nas apresentações do simpósio, revisão da literatura científica e discussões em grupo.


Assuntos
Humanos , Vírus da Hepatite E , Imunidade/imunologia , América Latina
11.
Pediatr Infect Dis J ; 36(7): 689-692, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28604562

RESUMO

The frequency of hepatitis A virus and hepatitis E virus infections and their cytokine profiles were analyzed in Mexican pediatric patients with acute hepatitis. A high frequency of coinfections was found. Significant overexpression of interleukin (IL)-4, IL-12, IL-13 and interferon-gamma during hepatitis A virus monoinfections and limited secretion of cytokines in hepatitis E virus infections were observed.


Assuntos
Coinfecção/imunologia , Citocinas/sangue , Hepatite A/complicações , Hepatite A/imunologia , Hepatite E/complicações , Hepatite E/imunologia , Doença Aguda/epidemiologia , Adolescente , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , Hepatite A/epidemiologia , Hepatite A/virologia , Vírus da Hepatite A/imunologia , Anticorpos Anti-Hepatite/sangue , Hepatite E/epidemiologia , Hepatite E/virologia , Vírus da Hepatite E/imunologia , Humanos , Lactente , Recém-Nascido , México/epidemiologia , Estudos Retrospectivos
12.
J Virol ; 83(22): 11890-901, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19759138

RESUMO

Noroviruses are a major cause of epidemic gastroenteritis in children and adults, and GII.4 has been the predominant genotype since its first documented occurrence in 1987. This study examined the evolutionary dynamics of GII.4 noroviruses over more than three decades to investigate possible mechanisms by which these viruses have emerged to become predominant. Stool samples (n = 5,424) from children hospitalized at the Children's Hospital in Washington, DC, between 1974 and 1991 were screened for the presence of noroviruses by a custom multiplex real-time reverse transcription-PCR. The complete genome sequences of five GII.4 noroviruses (three of which predate 1987 by more than a decade) in this archival collection were determined and compared to the sequences of contemporary strains. Evolutionary analysis determined that the GII.4 VP1 capsid gene evolved at a rate of 4.3 x 10(-3) nucleotide substitutions/site/year. Only six sites in the VP1 capsid protein were found to evolve under positive selection, most of them located in the shell domain. No unique mutations were observed in or around the two histoblood group antigen (HBGA) binding sites in the P region, indicating that this site has been conserved since the 1970s. The VP1 proteins from the 1974 to 1977 noroviruses contained a unique sequence of four consecutive amino acids in the P2 region, which formed an exposed protrusion on the modeled capsid structure. This protrusion and other observed sequence variations did not affect the HBGA binding profiles of recombinant virus-like particles derived from representative 1974 and 1977 noroviruses compared with more recent noroviruses. Our analysis of archival GII.4 norovirus strains suggests that this genotype has been circulating for more than three decades and provides new ancestral strain sequences for the analysis of GII.4 evolution.


Assuntos
Evolução Molecular , Norovirus/genética , Infecções por Caliciviridae/virologia , Criança , Variação Genética/genética , Genoma Viral/genética , Humanos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência
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