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1.
Emerg Infect Dis ; 23(8): 1411-1412, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28628464

RESUMO

During 2014-2016, we conducted mosquito-based Zika virus surveillance in Rio de Janeiro, Brazil. Results suggest that Zika virus was probably introduced into the area during May-November 2013 via multiple in-country sources. Furthermore, our results strengthen the hypothesis that Zika virus in the Americas originated in Brazil during October 2012-May 2013.


Assuntos
Aedes/virologia , Insetos Vetores/virologia , Zika virus/fisiologia , Animais , Brasil
2.
Arch Virol ; 162(6): 1577-1587, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28213871

RESUMO

Mayaro virus (MAYV) is an arthropod-borne virus and a member of the family Togaviridae, genus Alphavirus. Its infection leads to an acute illness accompanied by long-lasting arthralgia. To date, there are no antiviral drugs or vaccines against infection with MAYV and resources for the prevention or treatment of other alphaviruses are very limited. MAYV has served as a model to study the antiviral potential of several substances on alphavirus replication. In this work we evaluated the antiviral effect of seven new derivatives of thieno[2,3-b]pyridine against MAYV replication in a mammalian cell line. All derivatives were able to reduce viral production effectively at concentrations that were non-toxic for Vero cells. Molecular modeling assays predicted low toxicity risk and good oral bioavailability of the substances in humans. One of the molecules, selected for further study, demonstrated a strong anti-MAYV effect at early stages of replication, as it protected pre-treated cells and also during the late stages, affecting virus morphogenesis. This study is the first to demonstrate the antiviral effect of thienopyridine derivatives on MAYV replication in vitro, suggesting the potential application of these substances as antiviral molecules against alphaviruses. Additional in vivo research will be needed to expand the putative therapeutic applications.


Assuntos
Alphavirus/efeitos dos fármacos , Antivirais/química , Antivirais/farmacologia , Piridinas/farmacologia , Tiofenos/farmacologia , Animais , Chlorocebus aethiops , Humanos , Piridinas/síntese química , Piridinas/química , Piridinas/toxicidade , Tiofenos/síntese química , Tiofenos/química , Tiofenos/toxicidade , Células Vero , Replicação Viral/efeitos dos fármacos
3.
Sci Rep ; 4: 7552, 2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25518947

RESUMO

Cycloviruses, small ssDNA viruses of the Circoviridae family, have been identified in the cerebrospinal fluid from symptomatic human patients. One of these species, cyclovirus-Vietnam (CyCV-VN), was shown to be restricted to central and southern Vietnam. Here we report the detection of CyCV-VN species in stool samples from pigs and humans from Africa, far beyond their supposed limited geographic distribution.


Assuntos
Circoviridae/genética , Fezes/virologia , Adolescente , África , Animais , Sequência de Bases , Criança , Pré-Escolar , DNA Viral/genética , Genoma Viral/genética , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Filogenia , Suínos , Vietnã
7.
Mem Inst Oswaldo Cruz ; 107(5): 698-701, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22850966

RESUMO

Outbreaks caused by vaccine-derived polioviruses are challenging the final eradication of paralytic poliomyelitis. Therefore, the surveillance of the acute flaccid paralysis cases based on poliovirus isolation and characterization remains an essential activity. Due to the use of trivalent oral poliovirus vaccine (OPV), mixtures containing more than one serotype of Sabin-related polioviruses are frequently isolated from clinical samples. Because each poliovirus isolate needs to be individually analyzed, we designed polymerase chain reaction primers that can selectively distinguish and amplify a genomic segment of the three Sabin-related poliovirus serotypes present in mixtures, thus, optimizing the diagnosis and providing prompt information to support epidemiologic actions.


Assuntos
Primers do DNA/genética , Poliomielite/virologia , Vacina Antipólio Oral/genética , Poliovirus/genética , Genoma Viral , Humanos , Mutação , Fenótipo , Poliomielite/imunologia , Poliovirus/imunologia , Vacina Antipólio Oral/imunologia , Reação em Cadeia da Polimerase em Tempo Real
8.
Mem. Inst. Oswaldo Cruz ; 107(5): 698-701, Aug. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-643761

RESUMO

Outbreaks caused by vaccine-derived polioviruses are challenging the final eradication of paralytic poliomyelitis. Therefore, the surveillance of the acute flaccid paralysis cases based on poliovirus isolation and characterization remains an essential activity. Due to the use of trivalent oral poliovirus vaccine (OPV), mixtures containing more than one serotype of Sabin-related polioviruses are frequently isolated from clinical samples. Because each poliovirus isolate needs to be individually analyzed, we designed polymerase chain reaction primers that can selectively distinguish and amplify a genomic segment of the three Sabin-related poliovirus serotypes present in mixtures, thus, optimizing the diagnosis and providing prompt information to support epidemiologic actions.


Assuntos
Humanos , Primers do DNA/genética , Poliomielite/virologia , Vacina Antipólio Oral/genética , Poliovirus/genética , Genoma Viral , Mutação , Fenótipo , Poliomielite/imunologia , Vacina Antipólio Oral/imunologia , Poliovirus/imunologia , Reação em Cadeia da Polimerase em Tempo Real
9.
PLoS One ; 6(8): e23206, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21858030

RESUMO

BACKGROUND: Coxsackievirus A24 variant (CA24v) is the most prevalent viral pathogen associated with acute hemorrhagic conjunctivitis (AHC) outbreaks. Sixteen years after its first outbreak in Brazil, this agent reemerged in 2003 in Brazil, spread to nearly all states and caused outbreaks until 2005. In 2009, a new outbreak occurred in the northeast region of the country. In this study, we performed a viral isolation in cell culture and characterized clinical samples collected from patients presenting symptoms during the outbreak of 2005 in Vitória, Espírito Santo State (ES) and the outbreak of 2009 in Recife, Pernambuco State (PE). We also performed a phylogenetic analysis of worldwide strains and all meaningful Brazilian isolates since 2003. METHODS AND FINDINGS: Sterile cotton swabs were used to collect eye discharges, and all 210 clinical samples were used to inoculate cell cultures. Cytopathic effects in HEp-2 cells were seen in 58 of 180 (32%) samples from Vitória and 3 of 30 (10%) samples from Recife. Phylogenetic analysis based on a fragment of the VP1 and 3C gene revealed that the CA24v causing outbreaks in Brazil during the years 2003, 2004 and 2005 evolved from Asian isolates that had caused the South Korean outbreak of AHC during the summer of 2002. However, the 2009 outbreak of AHC in Pernambuco was originated from the reintroduction of a new CA24v strain that was circulating during 2007 in Asia, where CA24v outbreaks has been continuously reported since 1970. CONCLUSIONS: This study is the first phylogenetic analysis of AHC outbreaks caused by CA24v in Brazil. The results showed that Asian strains of CA24v were responsible for the outbreaks since 1987 and were independently introduced to Brazil in 2003 and 2009. Phylogenetic analysis of complete VP1 gene is a useful tool for studying the epidemiology of enteroviruses associated with outbreaks.


Assuntos
Conjuntivite Hemorrágica Aguda/virologia , Enterovirus Humano C/classificação , Enterovirus Humano C/genética , Filogenia , Proteases Virais 3C , Brasil/epidemiologia , Proteínas do Capsídeo/genética , Linhagem Celular Tumoral , Conjuntivite Hemorrágica Aguda/epidemiologia , Cisteína Endopeptidases/genética , Surtos de Doenças , Enterovirus Humano C/isolamento & purificação , Humanos , Dados de Sequência Molecular , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Proteínas Virais/genética
10.
Vet Microbiol ; 152(1-2): 74-87, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21601999

RESUMO

At present, Foot-and-Mouth Disease (FMD) has been successfully controlled in most territories of South America, where only Ecuador and Venezuela remain as endemic countries. In this context, the precise characterization of circulating viruses is of utmost importance. This work describes the first molecular epidemiology study performed with the complete VP(1)-coding region of 114 field isolates of FMD virus (FMDV) type O, collected in the Andean countries mainly during 2002-2008. Sequences were aligned and compared to isolates responsible for emergencies in the Southern Cone of the continent between the years 2000 and 2006, and to other representative type O viruses worldwide. The results showed that FMD type O viruses isolated in South America and analyzed up to date are placed in 11 different lineages within the Euro SA topotype. Five of these lineages included viruses circulating in Ecuador and Venezuela during 2002-2008. The last emergencies reported in already-free areas in the Andean region, showed close relationships with viruses circulating in these endemic countries. Andean lineages showed a clear separation from the unique lineage containing viruses responsible for the emergencies in the Southern Cone, reflecting the different livestock circuits and providing evidence that support the ecosystem dynamics in the region. A wide geographical dissemination of the same strain in short time intervals has been observed, pointing to animal movements as the most significant risk parameter. This fact, together with an important generation of viral variants in areas under weak control strategies, reinforce the need of stronger official controls, as well as for establishing multinational cooperative measures in the border areas.


Assuntos
Vírus da Febre Aftosa/classificação , Febre Aftosa/epidemiologia , Gado/virologia , Filogenia , Animais , Sequência de Bases , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/isolamento & purificação , Geografia , Epidemiologia Molecular , RNA Viral/genética , Análise de Sequência de RNA , América do Sul/epidemiologia
11.
Virus Res ; 124(1-2): 22-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17056146

RESUMO

The nucleotide sequences of the complete VP(1)-coding region of foot-and-mouth disease viruses (FMDV), type O, isolated during the recent emergencies of the disease in free areas of South America (Mato Grosso do Sul, Brazil, October 2005, and Corrientes, Argentina, February 2006), were determined. Also established were the complete VP(1)-coding sequences of viruses occurring in neighbouring locations between the years 2000 and 2003. A phylogenetic analysis was performed based on comparison with continental relevant field and vaccine strains, as well as with extra-continental representative viruses. The results show that the emergencies in Argentina and Brazil were caused by viruses presenting 93% genetic relatedness. Both variants are endogenous to South America, as they were placed within the Europe-South America topotype. When compared with the continental viruses available for the phylogenetic studies, they show the closest relationship with viruses responsible for previous emergencies in neighbouring free areas, or for sporadic outbreaks in the adjacent places with advanced eradication stages, presenting similarity values of at least 90% among them, and clustering together in a unique lineage. This lineage represents the only one sporadically appearing in the Southern Cone and differs from those including viruses presently circulating in the Andean region, reflecting the different livestock circuits and epidemiological scenarios.


Assuntos
Vírus da Febre Aftosa/classificação , Vírus da Febre Aftosa/genética , Febre Aftosa/virologia , Animais , Sequência de Bases , Proteínas do Capsídeo/genética , Febre Aftosa/epidemiologia , Vírus da Febre Aftosa/isolamento & purificação , Geografia , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , América do Sul/epidemiologia
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