RESUMO
Oropouche orthobunyavirus (OROV) has significant impact in public health in Amazon region. This arbovirus is one of the most common causes of febrile illness in Brazil, and is responsible for several epidemics since 1960's. In this study, we sequenced and characterized the complete coding sequences (S-, M- and L-RNA) of 35 OROV isolates from Brazil. Here, we classified 20 strains in genotype I from Pará and Maranhão states, nine as genotype II from Pará and Rondônia states confirmed, four classified into genotype III from Acre, Maranhão, Minas Gerais and Rondônia states and two genotype IV from Amazonas State. Also, we did not observe reassortment events involving the OROV isolates. In addition, we developed novel RT-PCR tools to identify reassortment events among OROV strains. These data will be useful to better understand the molecular epidemiology and diagnostic of OROV infections.
Assuntos
Infecções por Bunyaviridae/virologia , Genoma Viral , Genômica , Orthobunyavirus/genética , Vírus Reordenados/genética , Animais , Brasil/epidemiologia , Chlorocebus aethiops , Biologia Computacional/métodos , Genômica/métodos , Genótipo , Geografia Médica , Humanos , Epidemiologia Molecular , Anotação de Sequência Molecular , Tipagem Molecular , Orthobunyavirus/classificação , Filogenia , Células VeroRESUMO
Punta Toro virus (PTV), a member of the PTV complex, is a relatively common causative agent of febrile illness in Panama that is often misdiagnosed as 'dengue' or 'influenza'. Currently, only two named members make up this species complex, PTV and Buenaventura virus (BUEV). Genomic and antigenic characterization of 17 members of the PTV complex, nine of which were isolated from human acute febrile illness cases, reveals that this species complex is composed of six distant viruses. We propose to add four additional new viruses, designated Leticia virus, Cocle virus, Campana virus and Capira virus.
Assuntos
Infecções por Bunyaviridae/virologia , Febre/virologia , Phlebovirus/isolamento & purificação , Animais , Anticorpos Antivirais , Infecções por Bunyaviridae/imunologia , Reações Cruzadas , Febre/imunologia , Humanos , Insetos Vetores/virologia , Dados de Sequência Molecular , Panamá , Phlebovirus/classificação , Phlebovirus/genética , Phlebovirus/imunologia , Filogenia , Psychodidae/virologiaRESUMO
Dengue virus and its four serotypes (DENV-1 to DENV-4) infect 390 million people and are implicated in at least 25,000 deaths annually, with the largest disease burden in tropical and subtropical regions. We investigated the spatial dynamics of DENV-1, DENV-2 and DENV-3 in Brazil by applying a statistical framework to complete genome sequences. For all three serotypes, we estimated that the introduction of new lineages occurred within 7 to 10-year intervals. New lineages were most likely to be imported from the Caribbean region to the North and Northeast regions of Brazil, and then to disperse at a rate of approximately 0.5 km/day. Joint statistical analysis of evolutionary, epidemiological and ecological data indicates that aerial transportation of humans and/or vector mosquitoes, rather than Aedes aegypti infestation rates or geographical distances, determine dengue virus spread in Brazil.
Assuntos
Viagem Aérea , Vírus da Dengue/isolamento & purificação , Dengue/epidemiologia , Dengue/transmissão , Animais , Brasil/epidemiologia , Dengue/virologia , Vírus da Dengue/classificação , HumanosRESUMO
Globally, yellow fever virus infects nearly 200,000 people, leading to 30,000 deaths annually. Although the virus is endemic to Latin America, only a single genome from this region has been sequenced. Here, we report 12 Brazilian yellow fever virus complete genomes, their genetic traits, phylogenetic characterization, and phylogeographic dynamics. Variable 3' noncoding region (3'NCR) patterns and specific mutations throughout the open reading frame altered predicted secondary structures. Our findings suggest that whereas the introduction of yellow fever virus in Brazil led to genotype I-predominant dispersal throughout South and Central Americas, genotype II remained confined to Bolivia, Peru, and the western Brazilian Amazon.
Assuntos
Genoma Viral , Filogenia , Vírus da Febre Amarela/genética , Sequência de Bases , Brasil , Primers do DNA , Glicosilação , Reação em Cadeia da Polimerase , Vírus da Febre Amarela/classificaçãoRESUMO
Yellow fever virus (YFV), a member of the family Flaviviridae, genus Flavivirus is endemic to tropical areas of Africa and South America and is among the arboviruses that pose a threat to public health. Recent outbreaks in Brazil, Bolivia, and Paraguay and the observation that vectors capable of transmitting YFV are presenting in urban areas underscore the urgency of improving surveillance and diagnostic methods. Two novel methods (RT-hemi-nested-PCR and SYBR(®) Green qRT-PCR) for efficient detection of YFV strains circulating in South America have been developed. The methods were validated using samples obtained from golden hamsters infected experimentally with wild-type YFV strains as well as human serum and tissue samples with acute disease.
Assuntos
Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Virologia/métodos , Febre Amarela/diagnóstico , Vírus da Febre Amarela/isolamento & purificação , Animais , Cricetinae , Humanos , Mesocricetus , Soro/virologia , América do Sul , Febre Amarela/virologia , Vírus da Febre Amarela/genéticaRESUMO
While worldwide pandemic influenza A(H1N1) pdm case fatality rate (CFR) was 0.4%, Argentina's was 4.5%. A total of 34 strains from mild and severe cases were analyzed. A full genome sequencing was carried out on 26 of these, and a partial sequencing on the remaining eight. We observed no evidence that the high CFR can be attributed to direct virus changes. No evidence of re-assortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence was observed. Although the mutation D225G associated with severity in the latest reports from the Ukraine and Norway is not observed among the Argentine strains, an amino acid change in the area (S206T) surrounding the HA receptor binding domain was observed, the same previously established worldwide.
Assuntos
DNA Viral/genética , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , Mutação/genética , Adolescente , Adulto , Argentina/epidemiologia , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/mortalidade , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , RNA Viral/genética , Receptores Virais/genética , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Adulto JovemRESUMO
While worldwide pandemic influenza A(H1N1) pdm case fatality rate (CFR) was 0.4%, Argentina's was 4.5%. A total of 34 strains from mild and severe cases were analyzed. A full genome sequencing was carried out on 26 of these, and a partial sequencing on the remaining eight. We observed no evidence that the high CFR can be attributed to direct virus changes. No evidence of re-assortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence was observed. Although the mutation D225G associated with severity in the latest reports from the Ukraine and Norway is not observed among the Argentine strains, an amino acid change in the area (S206T) surrounding the HA receptor binding domain was observed, the same previously established worldwide.
Mientras que la tasa de letalidad (CFR) para (H1N1)pdm en todo el mundo era del 0.4%, en la Argentina la mortalidad observada fue de 4.5%. La secuenciación del genoma completo de 26 cepas de virus argentinos de influenza A (H1N1)pdm de casos leves y graves y de 8 cepas secuenciadas parcialmente no mostró evidencia de que la elevada tasa de letalidad se pueda atribuir directamente a cambios en el virus. No se encontraron hallazgos de recombinación, de mutaciones asociadas con la resistencia a los medicamentos antivirales ni de variaciones genéticas que puedan contribuir a la virulencia observada. Si bien la mutación D225G asociada con la gravedad, comunicada en informes procedentes de Ucrania y Noruega, no se ha encontrado en las cepas argentinas estudiadas, se ha observado un cambio aminoacídico en la región (S206T) en torno al dominio del sitio de unión al receptor en la HA, el mismo hallado en cepas distribuidas alrededor del mundo.
Assuntos
Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , DNA Viral/genética , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , Mutação/genética , Argentina/epidemiologia , Análise por Conglomerados , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/mortalidade , Dados de Sequência Molecular , Reprodutibilidade dos Testes , RNA Viral/genética , Receptores Virais/genética , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Initial reports in May 2009 of the novel influenza strain H1N1pdm estimated a case fatality rate (CFR) of 0.6%, similar to that of seasonal influenza. In July 2009, however, Argentina reported 3056 cases with 137 deaths, representing a CFR of 4.5%. Potential explanations for increased CFR included virus reassortment or genetic drift, or infection of a more vulnerable population. Virus genomic sequencing of 26 Argentinian samples representing both severe and mild disease indicated no evidence of reassortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence. Furthermore, no evidence was found for increased frequency of risk factors for H1N1pdm disease. METHODS/PRINCIPAL FINDINGS: We examined nasopharyngeal swab samples (NPS) from 199 cases of H1N1pdm infection from Argentina with MassTag PCR, testing for 33 additional microbial agents. The study population consisted of 199 H1N1pdm-infected subjects sampled between 23 June and 4 July 2009. Thirty-nine had severe disease defined as death (n = 20) or hospitalization (n = 19); 160 had mild disease. At least one additional agent of potential pathogenic importance was identified in 152 samples (76%), including Streptococcus pneumoniae (n = 62); Haemophilus influenzae (n = 104); human respiratory syncytial virus A (n = 11) and B (n = 1); human rhinovirus A (n = 1) and B (n = 4); human coronaviruses 229E (n = 1) and OC43 (n = 2); Klebsiella pneumoniae (n = 2); Acinetobacter baumannii (n = 2); Serratia marcescens (n = 1); and Staphylococcus aureus (n = 35) and methicillin-resistant S. aureus (MRSA, n = 6). The presence of S. pneumoniae was strongly correlated with severe disease. S. pneumoniae was present in 56.4% of severe cases versus 25% of mild cases; more than one-third of H1N1pdm NPS with S. pneumoniae were from subjects with severe disease (22 of 62 S. pneumoniae-positive NPS, p = 0.0004). In subjects 6 to 55 years of age, the adjusted odds ratio (OR) of severe disease in the presence of S. pneumoniae was 125.5 (95% confidence interval [CI], 16.95, 928.72; p<0.0001). CONCLUSIONS/SIGNIFICANCE: The association of S. pneumoniae with morbidity and mortality is established in the current and previous influenza pandemics. However, this study is the first to demonstrate the prognostic significance of non-invasive antemortem diagnosis of S. pneumoniae infection and may provide insights into clinical management.