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1.
Emerg Infect Dis ; 25(8): 1589-1591, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31310205

RESUMO

We report a disease outbreak caused by chikungunya virus in Zhejiang Province, China, in August 2017. Phylogenic analysis indicated that this virus belonged to the Indian Ocean clade of the East/Central/South African genotype and was imported by a traveler returning from Bangladesh.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya , Surtos de Doenças , Bangladesh , Febre de Chikungunya/história , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , China/epidemiologia , Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/virologia , Genoma Viral , História do Século XXI , Humanos , Filogenia , Doença Relacionada a Viagens
2.
3.
Emerg Microbes Infect ; 8(1): 962-972, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31259662

RESUMO

Europe is the world's leading tourism destination and is receiving every year travellers from areas with active arbovirus transmission. There is thus a threat of mosquito-borne virus emergence in Europe due to the presence of the invasive mosquito vector Aedes albopictus. Little attention has been paid about the possible role of indigenous mosquito species as vectors of emerging arboviruses. Here, we assessed the vector competence dynamic of Aedes geniculatus, a European anthropophilic mosquito species, for chikungunya virus (CHIKV) in comparison with an European population of Ae. albopictus. We revealed that Ae. geniculatus is highly susceptible to CHIKV infection and could transmit the virus. By specifically exploring the vector competence dynamic in both mosquito species, we revealed that the cumulative distribution of CHIKV incubation period in Ae. geniculatus was delayed by several days as compared to Ae. albopictus. Our results strengthen the importance of considering indigenous species as potential vectors for emerging arboviruses. They also revealed the importance of considering variation in arbovirus dissemination or transmission dynamics in mosquitoes when performing vector competence assays. We will discuss the implications of our results on a CHIKV outbreak dynamic in a theoretical framework.


Assuntos
Aedes/virologia , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Mosquitos Vetores/virologia , Aedes/fisiologia , Animais , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Europa (Continente) , Feminino , Humanos , Mosquitos Vetores/fisiologia
4.
PLoS Negl Trop Dis ; 13(6): e0007480, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31158221

RESUMO

Detection and sequencing of chikungunya virus (CHIKV) genome was performed using a combination of a modified reverse transcription loop-mediated isothermal amplification (RT-LAMP) method and a MinION sequencer. We developed the protocol for drying all the reagents for the RT-LAMP in a single reaction tube. Using this system, the CHIKV genome was effectively amplified under isothermal conditions, and used as a template for MinION sequencing with a laptop computer. Our in-house RT-LAMP method and MinION sequencing system were also validated with RNAs and serum samples from recent outbreaks of CHIKV patients in Brazil. The obtained sequence data confirmed the CHIKV outbreaks and identified the genotype. In summary, our established inexpensive on-site genome detection and sequencing system is applicable for both diagnosis of CHIKV infected patients and genotyping of the CHIKV virus in future outbreak in remote areas.


Assuntos
Febre de Chikungunya/diagnóstico , Vírus Chikungunya/isolamento & purificação , Técnicas de Genotipagem/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Análise de Sequência de DNA/métodos , Brasil , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Dessecação , Humanos , Transcrição Reversa , Temperatura Ambiente
5.
PLoS Negl Trop Dis ; 13(5): e0007231, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31067235

RESUMO

In recent years, an increasing number of outbreaks of Dengue, Chikungunya and Zika viruses have been reported in Asia and the Americas. Monitoring virus genotype diversity is crucial to understand the emergence and spread of outbreaks, both aspects that are vital to develop effective prevention and treatment strategies. Hence, we developed an efficient method to classify virus sequences with respect to their species and sub-species (i.e. serotype and/or genotype). This tool provides an easy-to-use software implementation of this new method and was validated on a large dataset assessing the classification performance with respect to whole-genome sequences and partial-genome sequences. Available online: http://krisp.org.za/tools.php.


Assuntos
Vírus Chikungunya/isolamento & purificação , Biologia Computacional/métodos , Vírus da Dengue/isolamento & purificação , Zika virus/isolamento & purificação , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/genética , Genoma Viral , Genótipo , Filogenia , Zika virus/classificação , Zika virus/genética , Infecção por Zika virus/virologia
6.
PLoS Negl Trop Dis ; 13(5): e0007332, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31095561

RESUMO

Chikungunya virus (CHIKV) is an RNA virus from the Togaviridae family transmitted by mosquitoes in both sylvatic and urban cycles. In humans, CHIKV infection leads to a febrile illness, denominated Chikungunya fever (CHIKF), commonly associated with more intense and debilitating outcomes. CHIKV arrived in Brazil in 2014 through two independent introductions: the Asian/Caribbean genotype entered through the North region and the African ECSA genotype was imported through the Northeast region. Following their initial introduction, both genotypes established their urban cycle among large naive human populations causing several outbreaks in the Americas. Here, we sequenced CHIKV genomes from a recent outbreak in the Northeast region of Brazil, employing an in-house developed Next-Generation Sequencing (NGS) protocol capable of directly detecting multiple known CHIKV genotypes from clinical positive samples. Our results demonstrate that both Asian/Caribbean and ECSA genotypes expanded their ranges, reaching cocirculation in the Northeast region of Brazil. In addition, our NGS data supports the findings of simultaneous infection by these two genotypes, suggesting that coinfection might be more common than previously thought in highly endemic areas. Future efforts to understand CHIKV epidemiology should thus take into consideration the possibility of coinfection by different genotypes in the human population.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Coinfecção/virologia , Genoma Viral , Adulto , Idoso , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/classificação , Coinfecção/epidemiologia , Surtos de Doenças , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma , Adulto Jovem
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(4): 415-418, 2019 Apr 06.
Artigo em Chinês | MEDLINE | ID: mdl-30982279

RESUMO

To study the epidemiology and etiology characteristics of first imported Chikungunya fever case in Henan province, China, 2017. The patient was confirmed by Chikungunya virus (CHIKV) infected as CHIKV ribonucleotide was continuously detected in his serum specimens. BHK-21 cell line was used for virus isolation, the strain was named CHIKV/Henan001/2017. CHIKV/Henan001/2017 belonged to genotype ECSA. The highest ribonucleotide homology sequence of highly conserved region E1 with CHIKV/Henan001/2017 was hk02 strain (99.8%), who was an imported strain to Hong Kong, China, 2016. Epidemiological information and laboratory testing confirmed it was an imported Chikungunya fever case in Henan province, 2017. No secondary case has been reported.


Assuntos
Febre de Chikungunya/epidemiologia , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , RNA Viral/genética , Febre de Chikungunya/diagnóstico , Vírus Chikungunya/classificação , China/epidemiologia , Genótipo , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Viagem , Proteínas Virais/genética
8.
Emerg Microbes Infect ; 8(1): 70-79, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30866761

RESUMO

Chikungunya virus (CHIKV) is a mosquito-borne pathogen that causes an acute febrile syndrome and severe, debilitating rheumatic disorders in humans that may persist for months. CHIKV's presence in Asia dates from at least 1954, but its epidemiological profile in the region remains poorly understood. We systematically reviewed CHIKV emergence, epidemiology, clinical features, atypical manifestations and distribution of virus genotypes, in 47 countries from South East Asia (SEA) and the Western Pacific Region (WPR) during the period 1954-2017. Following the Cochrane Collaboration guidelines, Pubmed and Scopus databases, surveillance reports available in the World Health Organisation (WHO) and government websites were systematically reviewed. Of the 3504 records identified, 461 were retained for data extraction. Although CHIKV has been circulating in Asia almost continuously since the 1950s, it has significantly expanded its geographic reach in the region from 2005 onwards. Most reports identified in the review originated from India. Although all ages and both sexes can be affected, younger children and the elderly are more prone to severe and occasionally fatal forms of the disease, with child fatalities recorded since 1963 from India. The most frequent clinical features identified were arthralgia, rash, fever and headache. Both the Asian and East-Central-South African (ECSA) genotypes circulate in SEA and WPR, with ECSA genotype now predominant. Our findings indicate a substantial but poorly documented burden of CHIKV infection in the Asia-Pacific region. An evidence-based consensus on typical clinical features of chikungunya could aid in enhanced diagnosis and improved surveillance of the disease.


Assuntos
Febre de Chikungunya/epidemiologia , Vírus Chikungunya/genética , Distribuição por Idade , Ásia Sudeste/epidemiologia , Febre de Chikungunya/mortalidade , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Medicina Baseada em Evidências , Feminino , Genótipo , Humanos , Masculino , Filogeografia
9.
Arch Virol ; 164(4): 1205-1208, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30729309

RESUMO

Chikungunya virus (CHIKV) is a reemerging arbovirus of the family Togaviridae that causes CHIKV fever, a disease that can extend from weeks to years depending on whether clinical signs of arthralgia persist. CHIKV is mainly transmitted by Aedes aegypti mosquitoes and possibly reached the Americas in 2013, causing an outbreak in Brazil in 2015. So far, two evolutionary lineages of CHIKV have been reported in Brazil: the Asian and the East-Central-South African (ECSA) lineages. In this study, six CHIKV isolates circulating in midwestern Brazil (Mato Grosso state) were isolated from patient sera, and their complete genomes were sequenced using a high-throughput sequencing platform. All of these isolates shared high nucleotide sequence similarity with CHIKV isolates from northeastern Brazil and were found to belong to the ECSA lineage. These CHIKV isolates did not contain the A226V or L210Q mutations that are associated with increased transmissibility by A. albopictus, suggesting that the CHIKV isolates circulating in midwestern Brazil are predominantly transmitted by A. aegypti.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Genoma Viral , Sequência de Bases , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Humanos , Dados de Sequência Molecular , Filogenia
10.
Emerg Infect Dis ; 25(2): 370-372, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30666947

RESUMO

In 2017, an unprecedented increase in febrile illness was observed in Dhaka, Bangladesh. Real-time reverse transcription PCR confirmed that 603 (40.2%) of 1,500 cases were chikungunya fever. Phylogenetic analysis revealed circulation of the non-A226V East/Central/South African genotype of chikungunya virus in Bangladesh.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Surtos de Doenças , Genótipo , Bangladesh/epidemiologia , Febre de Chikungunya/história , Vírus Chikungunya/classificação , História do Século XXI , Humanos , Filogenia , RNA Viral , Proteínas Virais/genética
11.
Viruses ; 10(11)2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30424530

RESUMO

Currently, Brazil lives a triple arboviruses epidemic (DENV, ZIKV and CHIKV) making the differential diagnosis difficult for health professionals. Here, we aimed to investigate chikungunya cases and the possible occurrence of co-infections during the epidemic in Amapá (AP) that started in 2014 when the first autochthonous cases were reported and in Rio de Janeiro (RJ) in 2016. We further performed molecular characterization and genotyping of representative strains. In AP, 51.4% of the suspected cases were confirmed for CHIKV, 71.0% (76/107). Of those, 24 co-infections by CHIKV/DENV, two by CHIKV/DENV-1, and two by CHIKV/DENV-4 were observed. In RJ, 76.9% of the suspected cases were confirmed for CHIKV and co-infections by CHIKV/DENV (n = 8) and by CHIKV/ZIKV (n = 17) were observed. Overall, fever, arthralgia, myalgia, prostration, edema, exanthema, conjunctival hyperemia, lower back pain, dizziness, nausea, retroorbital pain, and anorexia were the predominating chikungunya clinical symptoms described. All strains analyzed from AP belonged to the Asian genotype and no amino acid changes were observed. In RJ, the East-Central-South-African genotype (ECSA) circulation was demonstrated and no E1-A226V mutation was observed. Despite this, an E1-V156A substitution was characterized in two samples and for the first time, the E1-K211T mutation was reported in all samples analyzed.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya , Brasil/epidemiologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Coinfecção , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue/genética , Surtos de Doenças , Genoma Viral , Genótipo , Humanos , Filogenia , Vigilância da População , Zika virus , Infecção por Zika virus/epidemiologia
12.
PLoS One ; 13(10): e0204143, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30281633

RESUMO

Arboviruses are a major public health problem worldwide and are predominantly present in intertropical areas. Chikungunya, dengue and zika viruses have been implicated in recent epidemics in Asia, America and Africa. In Cameroon, data on these viruses are fragmentary. The purpose of this study was to determine the frequency of detection of these three viruses in febrile patients in Douala, Cameroon. A cross-sectional and descriptive study was conducted from March to April 2017 at the New-Bell District Hospital in Douala. Blood samples were collected from febrile patients and tested for malaria infections using Rapid Diagnostic test. Plasma harvested was later analyzed for the presence of chikungunya, dengue and zika viruses by a Trioplex real-time RT-PCR at Centre Pasteur of Cameroon. A total of 114 participants were included, of which 63.2% were females, reflecting a sex ratio (female/male) of 1.7. The median age was 26 years, range [0.25-81]. Eight (7%) of the 114 participants were infected with Dengue virus (DENV) among which 5 were identified as serotype 1. No cases of infection by either Zika virus or Chikungunya virus were detected. Three cases of dengue-malaria co-infection (13%) were recorded. No association was found between socio-demographic factors and dengue infection. The phylogenetic analysis of the partial envelope E gene showed that all the five DENV serotype 1 samples belonged to subtype V, similarly to strains from West African countries, particularly those from Nigeria, Senegal and Côte d'Ivoire. This study showed the circulation of DENV serotype 1 in febrile patients and raises the alarm for the establishment of a sustained surveillance system to detect cases and prevent potential outbreaks in Cameroon. The existence of dengue-malaria co-infections suggests that surveillance of arboviruses should not be limited to febrile, non-malarial cases.


Assuntos
Vírus da Dengue/classificação , Vírus da Dengue/isolamento & purificação , Dengue/virologia , Sorotipagem , Proteínas do Envelope Viral/genética , Adulto , Camarões , Febre de Chikungunya/sangue , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Coinfecção/sangue , Coinfecção/virologia , Estudos Transversais , Dengue/sangue , Vírus da Dengue/genética , Feminino , Febre/virologia , Hospitais de Distrito , Humanos , Masculino , Zika virus/classificação , Zika virus/genética , Zika virus/isolamento & purificação , Infecção por Zika virus/sangue , Infecção por Zika virus/virologia
13.
Epidemiol Infect ; 146(16): 2056-2058, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30182863

RESUMO

Chikungunya virus (CHIKV) is an arbovirus transmitted by Aedes mosquitoes that was first identified in Brazil in 2014. It causes a febrile illness characterised by severe arthralgia and rash. Our group investigated a suspected CHIKV outbreak in Governador Valadares, state of Minas Gerais, Brazil and from 25 acute-phase patients, 10 had qRT-PCR positive sera samples and had E1 partial sequence amplified and Sanger sequenced. Samples were identified as East/Central/South African (ECSA) genotype by phylogenetic analysis and clustered with CHIKV sequences isolated in the neighbour state of Bahia. Our findings confirm previous predictions that ECSA genotype would spread through northeast and southeast of Brazil.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/isolamento & purificação , Surtos de Doenças , Genótipo , Brasil/epidemiologia , Vírus Chikungunya/genética , Análise por Conglomerados , Humanos , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Soro/virologia , Proteínas do Envelope Viral/genética
14.
J Biol Chem ; 293(45): 17536-17545, 2018 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-30242123

RESUMO

Climate change and human globalization have spurred the rapid spread of mosquito-borne diseases to naïve populations. One such emerging virus of public health concern is chikungunya virus (CHIKV), a member of the Togaviridae family, genus Alphavirus CHIKV pathogenesis is predominately characterized by acute febrile symptoms and severe arthralgia, which can persist in the host long after viral clearance. CHIKV has also been implicated in cases of acute encephalomyelitis, and its vertical transmission has been reported. Currently, no FDA-approved treatments exist for this virus. Recoding elements help expand the coding capacity in many viruses and therefore represent potential therapeutic targets in antiviral treatments. Here, we report the molecular and structural characterization of two CHIKV translational recoding signals: a termination codon read-through (TCR) element located between the nonstructural protein 3 and 4 genes and a programmed -1 ribosomal frameshift (-1 PRF) signal located toward the 3' end of the CHIKV 6K gene. Using Dual-Luciferase and immunoblot assays in HEK293T and U87MG mammalian cell lines, we validated and genetically characterized efficient TCR and -1 PRF. Analyses of RNA chemical modification data with selective 2'-hydroxyl acylation and primer extension (SHAPE) assays revealed that CHIKV -1 PRF is stimulated by a tightly structured, triple-stem hairpin element, consistent with previous observations in alphaviruses, and that the TCR signal is composed of a single large multibulged hairpin element. These findings illuminate the roles of RNA structure in translational recoding and provide critical information relevant for design of live-attenuated vaccines against CHIKV and related viruses.


Assuntos
Vírus Chikungunya/genética , RNA Mensageiro/química , RNA Viral/química , Linhagem Celular Tumoral , Vírus Chikungunya/classificação , Células HEK293 , Humanos , Filogenia , RNA Mensageiro/genética , RNA Viral/genética , Sequências Reguladoras de Ácido Ribonucleico
15.
Arch Virol ; 163(11): 3135-3140, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30073419

RESUMO

During 2015-2017, chikungunya virus (CHIKV) showed a resurgence in several parts of India with Karnataka, Maharashtra and New Delhi accounting for a majority of the cases. E2-E1 gene based characterization revealed Indian subcontinent sublineage strains possessing Aedes aegypti mosquito-adaptive mutations E1: K211E and E2:V264A, with the 211 site positively selected. Novel mutational sites E1: K16E/Q, E1: K132Q/T, E1: S355T, E2: C19R and E2:S185Y could be associated with epitopes or virulence determining domains. The study examines the role of host, vector and viral factors and fills gaps in our molecular epidemiology data for these regions which are known to possess a dynamic population.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Proteínas do Envelope Viral/genética , Aedes/fisiologia , Aedes/virologia , Animais , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/transmissão , Vírus Chikungunya/classificação , Vírus Chikungunya/isolamento & purificação , Vírus Chikungunya/patogenicidade , Surtos de Doenças , Índia/epidemiologia , Epidemiologia Molecular , Mosquitos Vetores/fisiologia , Mosquitos Vetores/virologia , Mutação , Filogenia , Virulência
16.
Virol J ; 15(1): 130, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30126424

RESUMO

BACKGROUND: Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus within the family Togaviridae, which has attracted global attention due to its recent re-emergence. In one of our previous studies, we successfully isolated two CHIKV virus strains, SZ1050 and SZ1239, from the serum samples of two imported patients in 2010 and 2012, respectively. However, the differences in their genome characters and cell tropisms remain undefined. METHODS: We extracted the RNA of two CHIKV isolates and performed PCR to determine the sequence of the whole viral genomes. The genotypes were classified by phylogenetic analysis using the Mega 6.0 software. Furthermore, the cell tropisms of the two CHIKV isolates were evaluated in 13 cell lines. RESULTS: The lengths of the whole genomes for SZ1050 and SZ1239 were 11,844 nt and 12,000 nt, respectively. Phylogenetic analysis indicated that SZ1050 belonged to the Indian Ocean lineage (IOL), while SZ1239 was of the Asian lineage. Comparing to the prototype strain S27, a gap of 7 aa in the nsP3 gene and missing of one repeated sequence element (RSE) in the 3' UTR were observed in SZ1239. The E1-A226V mutation was not detected in both strains. SZ1050 and SZ1239 could infect most of the evaluated mammalian epithelial cells. The K562 cells were permissive for both SZ1050 and SZ1239 while the U937 cells were refractory to both viruses. For Aedes cell lines C6/36 and Aag-2, both SZ1050 and SZ1239 were able to infect and replicate efficiently. CONCLUSIONS: Compared to the prototype S27 virus, some deletions and mutations were found in the genomes of SZ1050 and SZ1239. Both viruses were susceptible to most evaluated epithelia or fibroblast cells and Aedes cell lines including C6/36 and Aag-2 in spite of marginal difference.


Assuntos
Vírus Chikungunya/genética , Vírus Chikungunya/fisiologia , Variação Genética , Genótipo , RNA Viral/genética , Tropismo Viral , Animais , Ásia , Linhagem Celular , Vírus Chikungunya/classificação , Vírus Chikungunya/isolamento & purificação , Humanos , Mutação , Filogenia , Homologia de Sequência , Sequenciamento Completo do Genoma
17.
PLoS Negl Trop Dis ; 12(7): e0006670, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30059496

RESUMO

Chikungunya virus (CHIKV) has been detected sporadically since the 1950s and includes three distinct co-circulating genotypes. In late 2013, the Asian genotype of CHIKV was responsible for the Caribbean outbreak (CO) that rapidly became an epidemic throughout the Americas. There is a limited understanding of the molecular evolution of CHIKV in the Americas during this epidemic. We sequenced 185 complete CHIKV genomes collected mainly from Nicaragua in Central America and Florida in the United States during the 2014-2015 Caribbean/Americas epidemic. Our comprehensive phylogenetic analyses estimated the epidemic history of the Asian genotype and the recent Caribbean outbreak (CO) clade, revealed considerable genetic diversity within the CO clade, and described different epidemiological dynamics of CHIKV in the Americas. Specifically, we identified multiple introductions in both Nicaragua and Florida, with rapid local spread of viruses in Nicaragua but limited autochthonous transmission in Florida in the US. Our phylogenetic analysis also showed phylogeographic clustering of the CO clade. In addition, we identified the significant amino acid substitutions that were observed across the entire Asian genotype during its evolution and examined amino acid changes that were specific to the CO clade. Deep sequencing analysis identified specific minor variants present in clinical specimens below-consensus levels. Finally, we investigated the association between viral phylogeny and geographic/clinical metadata in Nicaragua. To date, this study represents the largest single collection of CHIKV complete genomes during the Caribbean/Americas epidemic and significantly expands our understanding of the emergence and evolution of CHIKV CO clade in the Americas.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Adolescente , Ásia/epidemiologia , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Vírus Chikungunya/fisiologia , Criança , Pré-Escolar , Epidemias , Feminino , Variação Genética , Genoma Viral , Genótipo , Humanos , Masculino , Nicarágua/epidemiologia , Filogenia , Viagem , Estados Unidos/epidemiologia , Adulto Jovem
18.
PLoS One ; 13(6): e0199494, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29953474

RESUMO

Reverse genetics systems provide the opportunity to manipulate viral genomes and have been widely used to study RNA viruses and to develop new antiviral compounds and vaccine strategies. The recently described method called ISA (Infectious Subgenomic Amplicons) gives the possibility to rescue RNA viruses in days. We demonstrated in cell culture that the use of the ISA method led to a higher genetic diversity of viral populations than that observed using infectious clone technology. However, no replicative fitness difference was observed. In the present study, we used the chikungunya virus as a model to compare in Aedes aegypti and Aedes albopictus mosquitoes the genotypic and phenotypic characteristics of viruses produced either from an infectious clone or using the ISA method. We confirmed the results found in cellulo corroborating that the use of the ISA method was associated with higher genetic diversity of viral populations in mosquitoes but did not affect the vector competence validating its use for in vivo experiments.


Assuntos
Aedes/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Genoma Viral , RNA Viral , Animais , Evolução Biológica , Feminino , Variação Genética , Células Vero
19.
Virol J ; 15(1): 84, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29751761

RESUMO

BACKGROUND: Chikungunya virus (CHIKV) and dengue virus (DENV) are arboviruses that share the same Aedes mosquito vector, and there is much overlap in endemic areas. In India, co-infection with both viruses is often reported. Clinical manifestations of Chikungunya fever is often confused with dengue fever because clinical symptoms of both infections are similar. It is, therefore, difficult to differentiate from those of other febrile illnesses, especially dengue fever. We previously developed a CHIKV antigen detection immunochromatography (IC) rapid diagnosis kit [1]. The current study examined the efficacy of previously mentioned IC kit in India, a dengue-endemic country. METHODS: Sera from 104 CHIKV-positive (by qRT-PCR) and/or IgM-positive (ELISA) subjects collected in 2016, were examined. Fifteen samples from individuals with CHIKV-negative/DENV-positive and 4 samples from healthy individuals were also examined. Of the 104 CHIKV-positive sera, 20 were co-infected with DENV. RESULTS: The sensitivity, specificity and overall agreement of the IC assay were 93.7, 95.5 and 94.3%, respectively, using qRT-PCR as a gold standard. Also, there was a strong, statistically significant positive correlation between the IC kit device score and the CHIKV RNA copy number. The IC kit detected CHIKV antigen even in DENV-co-infected patient sera and did not cross-react with DENV NS1-positive/CHIKV-negative samples. CONCLUSIONS: The results suggest that the IC kit is useful for rapid diagnosis of CHIKV in endemic areas in which both CHIKV and DENV are circulating.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Febre de Chikungunya/diagnóstico , Vírus Chikungunya/imunologia , Cromatografia de Afinidade/métodos , Dengue/diagnóstico , Aedes/virologia , Animais , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Coinfecção , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Diagnóstico Diferencial , Humanos , Soros Imunes/química , Índia/epidemiologia , Mosquitos Vetores/virologia , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
20.
PLoS Negl Trop Dis ; 12(5): e0006448, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29813065

RESUMO

BACKGROUND: A single-tube one-step real-time reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for rapid detection of chikungunya virus (CHIKV) targeting the conserved 6K-E1 target region was developed. The assay was validated with sera collected from a CHIKV outbreak in Senegal in 2015. METHODOLOGY/PRINCIPAL FINDINGS: A novel design approach by combining Principal Component Analysis and phylogenetic analysis of 110 available CHIKV sequences and the LAMP oligonucleotide design software LAVA was used. The assay was evaluated with an External Quality Assessment panel from the European Network for Diagnostics of "Imported" Viral Diseases and was shown to be sensitive and specific and did not cross-detect other arboviruses. The limit of detection as determined by probit analysis, was 163 molecules, and 100% reproducibility in the assays was obtained for 103 molecules (7/8 repetitions were positive for 102 molecules). The assay was validated using 35 RNA samples extracted from sera, and results were compared with those obtained by quantitative RT-PCR carried out at the Institut Pasteur Dakar, demonstrating that the RT-LAMP is 100% sensitive and 80% specific, with a positive predictive value of 97% and negative predictive value of 100%. CONCLUSIONS/SIGNIFICANCE: The RT-LAMP appeared to show superior performance with material stored for months compared to qRT-PCR and can be therefore recommended for use in infrastructures with poor settings.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Genoma Viral , Técnicas de Amplificação de Ácido Nucleico/métodos , Febre de Chikungunya/diagnóstico , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Primers do DNA/genética , Humanos , Filogenia , Sensibilidade e Especificidade
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