| una virus: first report of human infection in argentina. | una virus (unav), togaviridae family, is widely distributed in south america, where infections have been detected in mosquitoes and vertebrate hosts (humans, birds and horses). we analyzed human sera from córdoba inhabitants aged 44 to 89 years and using a neutralization test, we found a prevalence of unav antibodies of 3.8% (3/79). the low titers detected suggest past infections probably acquired in rural areas of the province of córdoba (central argentina). none sera were found positive for ma ... | 2003 | 12754579 |
| mayaro virus in wild mammals, french guiana. | | 2003 | 14609474 |
| duplex reverse transcription-pcr followed by nested pcr assays for detection and identification of brazilian alphaviruses and flaviviruses. | a new approach was developed for the rapid detection and identification of brazilian alphaviruses and flaviviruses. the methodology involves the genus-specific detection of alphavirus and flavivirus by a duplex reverse transcription-pcr (d-rt-pcr), followed by multiplex nested pcr (m-n-pcr) or nested pcr (n-pcr) assays for species-specific identification. by this protocol, 25 arboviruses were specifically detected and identified. detection levels between 10(1.3) and 10(3.5) 50% tissue culture in ... | 2005 | 15695666 |
| mayaro virus: complete nucleotide sequence and phylogenetic relationships with other alphaviruses. | mayaro (may) virus is a member of the genus alphavirus in the family togaviridae. alphaviruses are distributed throughout the world and cause a wide range of diseases in humans and animals. here, we determined the complete nucleotide sequence of may from a viral strain isolated from a french guianese patient. the deduced may genome was 11,429 nucleotides in length, excluding the 5' cap nucleotide and 3' poly(a) tail. nucleotide and amino acid homologies, as well as phylogenetic analyses of the o ... | 2006 | 16343676 |
| phylogenetic analysis of buggy creek virus: evidence for multiple clades in the western great plains, united states of america. | we present the first detailed phylogenetic analysis of buggy creek virus (bcrv), a poorly known alphavirus with transmission cycles involving a cimicid swallow bug (oeciacus vicarius) vector and cliff swallows (petrochelidon pyrrhonota) and house sparrows (passer domesticus) as the principal avian hosts. nucleotide sequences of a 2,075-bp viral envelope glycoprotein-coding region, covering the entire pe2 gene, were determined for 33 bcrv isolates taken from swallow bugs at cliff swallow colonies ... | 2006 | 16936062 |
| infection by una virus (alphavirus; togaviridae) and risk factor analysis in black howler monkeys (alouatta caraya) from paraguay and argentina. | a neutralizing antibody (ntab) survey on una and mayaro viruses in black howler monkeys (aloutta caraya) from subtropical regions of argentina and paraguay was carried out. risk factors for infection in monkeys were analyzed. no positive sera for mayaro virus were detected. a prevalence of 73% (61/84) of ntab against unav was detected with titers ranging from 20 to 1280. according to the statistical analysis performed, the monkey's age was a significant risk factor, but not the origin or sex. th ... | 2007 | 17658571 |
| discovery of frameshifting in alphavirus 6k resolves a 20-year enigma. | the genus alphavirus includes several potentially lethal human viruses. additionally, species such as sindbis virus and semliki forest virus are important vectors for gene therapy, vaccination and cancer research, and important models for virion assembly and structural analyses. the genome encodes nine known proteins, including the small '6k' protein. 6k appears to be involved in envelope protein processing, membrane permeabilization, virion assembly and virus budding. in protein gels, 6k migrat ... | 2008 | 18822126 |
| evolutionary patterns of eastern equine encephalitis virus in north versus south america suggest ecological differences and taxonomic revision. | the eastern equine encephalitis (eee) complex consists of four distinct genetic lineages: one that circulates in north america (na eeev) and the caribbean and three that circulate in central and south america (sa eeev). differences in their geographic, pathogenic, and epidemiologic profiles prompted evaluation of their genetic diversity and evolutionary histories. the structural polyprotein open reading frames of all available sa eeev and recent na eeev isolates were sequenced and used in evolut ... | 2010 | 19889755 |
| mayaro fever virus, brazilian amazon. | in february 2008, a mayaro fever virus (mayv) outbreak occurred in a settlement in santa barbara municipality, northern brazil. patients had rash, fever, and severe arthralgia lasting up to 7 days. immunoglobulin m against mayv was detected by elisa in 36 persons; 3 mayv isolates sequenced were characterized as genotype d. | 2009 | 19891877 |
| Genome scale phylogeny of the Alphavirus genus suggests a marine origin. | The genus Alphavirus comprises a diverse group of viruses, including some that cause severe disease. Using full-length sequences of all known alphaviruses, we produced a robust and comprehensive phylogeny of the Alphavirus genus, presenting a more complete evolutionary history of these viruses compared to previous studies based on partial sequences. Our phylogeny suggests the origin of the alphaviruses occurred in the southern oceans and spread equally through the Old and New World. Since lice a ... | 2011 | 22190718 |
| experimental transmission of mayaro virus by aedes aegypti. | outbreaks of mayaro fever have been associated with a sylvatic cycle of mayaro virus (mayv) transmission in south america. to evaluate the potential for a common urban mosquito to transmit mayv, laboratory vector competence studies were performed with aedes aegypti from iquitos, peru. oral infection in ae. aegypti ranged from 0% (0/31) to 84% (31/37), with blood meal virus titers between 3.4 log(10) and 7.3 log(10) plaque-forming units (pfu)/ml. transmission of mayv by 70% (21/30) of infected mo ... | 2011 | 21976583 |
| hunting in the rainforest and mayaro virus infection: an emerging alphavirus in ecuador. | the objectives of this report were to document the potential presence of mayaro virus infection in ecuador and to examine potential risk factors for mayaro virus infection among the personnel of a military garrison in the amazonian rainforest. | 2011 | 22223990 |
| sindbis and middelburg old world alphaviruses associated with neurologic disease in horses, south africa. | old world alphaviruses were identified in 52 of 623 horses with febrile or neurologic disease in south africa. five of 8 sindbis virus infections were mild; 2 of 3 fatal cases involved co-infections. of 44 middelburg virus infections, 28 caused neurologic disease; 12 were fatal. middelburg virus likely has zoonotic potential. | 0 | 26583836 |
| broadly neutralizing alphavirus antibodies bind an epitope on e2 and inhibit entry and egress. | we screened a panel of mouse and human monoclonal antibodies (mabs) against chikungunya virus and identified several with inhibitory activity against multiple alphaviruses. passive transfer of broadly neutralizing mabs protected mice against infection by chikungunya, mayaro, and o'nyong'nyong alphaviruses. using alanine-scanning mutagenesis, loss-of-function recombinant proteins and viruses, and multiple functional assays, we determined that broadly neutralizing mabs block multiple steps in the ... | 2015 | 26553503 |
| evolutionary genetics and vector adaptation of recombinant viruses of the western equine encephalitis antigenic complex provides new insights into alphavirus diversity and host switching. | western equine encephalitis virus (weev), highlands j virus (hjv), and fort morgan virus (fmv) are the sole representatives of the wee antigenic complex of the genus alphavirus, family togaviridae, that are endemic to north america. all three viruses have their ancestry in a recombination event involving eastern equine encephalitis virus (eeev) and a sindbis (sin)-like virus that gave rise to a chimeric alphavirus that subsequently diversified into the present-day weev, hjv, and fmv. here, we pr ... | 2014 | 25463613 |
| in- silico exploration of thirty alphavirus genomes for analysis of the simple sequence repeats. | the compilation of simple sequence repeats (ssrs) in viruses and its analysis with reference to incidence, distribution and variation would be instrumental in understanding the functional and evolutionary aspects of repeat sequences. present study encompasses the analysis of ssrs across 30 species of alphaviruses. the full length genome sequences, assessed from ncbi were used for extraction and analysis of repeat sequences using imex software. the repeats of different motif sizes (mono- to penta ... | 2014 | 25606453 |
| a tyrosine-to-histidine switch at position 18 of the ross river virus e2 glycoprotein is a determinant of virus fitness in disparate hosts. | arthritogenic alphaviruses are human pathogens maintained in nature through alternating replication in vertebrates and mosquitoes. using chimeric viruses, we previously reported that replacement of the pe2 coding region of the t48 strain of ross river virus (rrv-t48) with that from the attenuated dc5692 strain, which differ by 7 amino acids, resulted in an attenuated disease phenotype in a mouse model of rrv-induced rheumatic disease. here, we demonstrate that introduction of one of these amino ... | 2013 | 23514884 |
| adaptive changes in alphavirus mrna translation allowed colonization of vertebrate hosts. | members of the alphavirus genus are arboviruses that alternate replication in mosquitoes and vertebrate hosts. in vertebrate cells, the alphavirus resists the activation of antiviral rna-activated protein kinase (pkr) by the presence of a prominent rna structure (downstream loop [dlp]) located in viral 26s transcripts, which allows an eif2-independent translation initiation of these mrnas. this article shows that dlp structure is essential for replication of sindbis virus (sinv) in vertebrate ce ... | 2012 | 22761388 |
| an rna trapping mechanism in alphavirus mrna promotes ribosome stalling and translation initiation. | during translation initiation, eukaryotic initiation factor 2 (eif2) delivers the met-trna to the 40s ribosomal subunit to locate the initiation codon (augi) of mrna during the scanning process. stress-induced eif2 phosphorylation leads to a general blockade of translation initiation and represents a key antiviral pathway in mammals. however, some viral mrnas can initiate translation in the presence of phosphorylated eif2 via stable rna stem-loop structures (dlp; downstream loop) located in thei ... | 2016 | 26984530 |
| multi-gene detection and identification of mosquito-borne rna viruses using an oligonucleotide microarray. | arthropod-borne viruses are important emerging pathogens world-wide. viruses transmitted by mosquitoes, such as dengue, yellow fever, and japanese encephalitis viruses, infect hundreds of millions of people and animals each year. global surveillance of these viruses in mosquito vectors using molecular based assays is critical for prevention and control of the associated diseases. here, we report an oligonucleotide dna microarray design, termed arbochip5.1, for multi-gene detection and identifica ... | 2013 | 23967358 |
| genetic diversity of venezuelan alphaviruses and circulation of a venezuelan equine encephalitis virus subtype iab strain during an interepizootic period. | several species of alphaviruses have been previously described in the americas, some of which are associated with encephalitis and others are associated with arthralgia. venezuelan equine encephalitis virus (veev) and eastern equine encephalitis virus (eeev) are endemic to venezuela, with the former being responsible for major outbreaks of severe and often fatal disease in animals and humans. the aim of this study was to analyze the genetic diversity of venezuelan alphaviruses isolated during tw ... | 2015 | 25940191 |
| neutralising antibodies for mayaro virus in pantanal, brazil. | the pantanal hosts diverse wildlife species and therefore is a hotspot for arbovirus studies in south america. a serosurvey for mayaro virus (mayv), eastern (eeev), western (weev) and venezuelan (veev) equine encephalitis viruses was conducted with 237 sheep, 87 free-ranging caimans and 748 equids, including 37 collected from a ranch where a neurologic disorder outbreak had been recently reported. sera were tested for specific viral antibodies using plaque-reduction neutralisation test. from a t ... | 2015 | 25742272 |
| mayaro virus infection in amazonia: a multimodel inference approach to risk factor assessment. | arboviral diseases are major global public health threats. yet, our understanding of infection risk factors is, with a few exceptions, considerably limited. a crucial shortcoming is the widespread use of analytical methods generally not suited for observational data--particularly null hypothesis-testing (nht) and step-wise regression (swr). using mayaro virus (mayv) as a case study, here we compare information theory-based multimodel inference (mmi) with conventional analyses for arboviral infec ... | 2012 | 23071852 |
| assessment of plaque assay methods for alphaviruses. | viruses from the alphavirus genus are responsible for numerous arboviral diseases impacting human health throughout the world. confirmation of acute alphavirus infection is based on viral isolation, identification of viral rna, or a fourfold or greater increase in antibody titers between acute and convalescent samples. in convalescence, the specificity of antibodies to an alphavirus may be confirmed by plaque reduction neutralization test. to identify the best method for alphavirus and neutraliz ... | 2013 | 23085307 |
| [the cytopathic effect of una virus on a bhk-21 culture]. | | 1969 | 5393526 |
| [the biological characteristics of una virus. 2]. | | 2016 | 5793981 |