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2.
Res Dev Disabil ; 115: 103939, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33934926

ABSTRACT

BACKGROUND: Trauma is a significant underlying factor in the multimorbidity of people with Intellectual and/or Development Disabilities (IDD). This relationship is further complicated by a growing recognition of a subset of multiply stigmatized individuals with an IDD and complex, intersecting health and social needs. AIM: The aim of this review was to examine what is known about trauma and people with an IDD and complex needs, as defined by Community Living British Columbia's (CLBC) Multiple, Complex Needs (MCN) framework, through a broad review of relevant literature. METHOD AND PROCEDURES: We conducted a scoping review of the peer-reviewed (9 disability journals; 7 academic databases) and grey (2 grey literature databases) on IDD and trauma through an inclusive approach that used search criteria drawn from the defining features of CLBC's MCN Framework. OUTCOMES AND RESULTS: Apart from there being a limited amount of research on trauma and IDD, two key findings emerged. Through differing approaches that get at issues of trauma in different ways (i.e., through adverse life events or experiences of abuse), the first finding is that the research related to trauma and IDD is not cleanly linked together. The second is the focus on treatment services or interventions and not on what's happening at the organizational or system level. CONCLUSION AND IMPLICATIONS: There is limited research on trauma and IDD making it even more important to unify the evidence that exists. However, the literature is not integrated across different theoretical and disciplinary perspectives. In addition, the focus of trauma-related research that is occurring is interventions at the individual versus system level. Also needed are studies that explore trauma-informed practice from an organizational or top-down perspective.


Subject(s)
Disabled Persons , Intellectual Disability , Child , Databases, Factual , Developmental Disabilities/epidemiology , Humans , Intellectual Disability/epidemiology
3.
PLoS One ; 10(2): e0117849, 2015.
Article in English | MEDLINE | ID: mdl-25719412

ABSTRACT

To generate the most diverse phylogenetic dataset for the flaviviruses to date, we determined the genomic sequences and phylogenetic relationships of 14 flaviviruses, of which 10 are primarily associated with Culex spp. mosquitoes. We analyze these data, in conjunction with a comprehensive collection of flavivirus genomes, to characterize flavivirus evolutionary and biogeographic history in unprecedented detail and breadth. Based on the presumed introduction of yellow fever virus into the Americas via the transatlantic slave trade, we extrapolated a timescale for a relevant subset of flaviviruses whose evolutionary history, shows that different Culex-spp. associated flaviviruses have been introduced from the Old World to the New World on at least five separate occasions, with 2 different sets of factors likely to have contributed to the dispersal of the different viruses. We also discuss the significance of programmed ribosomal frameshifting in a central region of the polyprotein open reading frame in some mosquito-associated flaviviruses.


Subject(s)
Evolution, Molecular , Flavivirus/genetics , Genome, Viral , Open Reading Frames , Phylogeny , Base Sequence , Flavivirus/classification , Flavivirus/physiology , Frameshifting, Ribosomal , Molecular Sequence Data , Phylogeography
4.
Virology ; 464-465: 320-329, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25108382

ABSTRACT

Novel flaviviruses that are genetically related to pathogenic mosquito-borne flaviviruses (MBFV) have been isolated from mosquitoes in various geographical locations, including Finland. We isolated and characterized another novel virus of this group from Finnish mosquitoes collected in 2007, designated as Ilomantsi virus (ILOV). Unlike the MBFV that infect both vertebrates and mosquitoes, the MBFV-related viruses appear to be specific to mosquitoes similar to the insect-specific flaviviruses (ISFs). In this overview of MBFV-related viruses we conclude that they differ from the ISFs genetically and antigenically. Phylogenetic analyses separated the MBFV-related viruses isolated in Africa, the Middle East and South America from those isolated in Europe and Asia. Serological cross-reactions of MBFV-related viruses with other flaviviruses and their potential for vector-borne transmission require further characterization. The divergent MBFV-related viruses are probably significantly under sampled to date and provide new information on the variety, properties and evolution of vector-borne flaviviruses.


Subject(s)
Culicidae/virology , Evolution, Molecular , Flavivirus/classification , Flavivirus/isolation & purification , Insect Vectors/virology , Phylogeny , Africa , Animals , Base Sequence , Culicidae/classification , Female , Flavivirus/genetics , Flavivirus Infections/transmission , Flavivirus Infections/virology , Humans , Male , Molecular Sequence Data
5.
J Virol ; 88(1): 10-20, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24155369

ABSTRACT

The genome sequences of new viruses often contain many "orphan" or "taxon-specific" proteins apparently lacking homologs. However, because viral proteins evolve very fast, commonly used sequence similarity detection methods such as BLAST may overlook homologs. We analyzed a data set of proteins from RNA viruses characterized as "genus specific" by BLAST. More powerful methods developed recently, such as HHblits or HHpred (available through web-based, user-friendly interfaces), could detect distant homologs of a quarter of these proteins, suggesting that these methods should be used to annotate viral genomes. In-depth manual analyses of a subset of the remaining sequences, guided by contextual information such as taxonomy, gene order, or domain cooccurrence, identified distant homologs of another third. Thus, a combination of powerful automated methods and manual analyses can uncover distant homologs of many proteins thought to be orphans. We expect these methodological results to be also applicable to cellular organisms, since they generally evolve much more slowly than RNA viruses. As an application, we reanalyzed the genome of a bee pathogen, Chronic bee paralysis virus (CBPV). We could identify homologs of most of its proteins thought to be orphans; in each case, identifying homologs provided functional clues. We discovered that CBPV encodes a domain homologous to the Alphavirus methyltransferase-guanylyltransferase; a putative membrane protein, SP24, with homologs in unrelated insect viruses and insect-transmitted plant viruses having different morphologies (cileviruses, higreviruses, blunerviruses, negeviruses); and a putative virion glycoprotein, ORF2, also found in negeviruses. SP24 and ORF2 are probably major structural components of the virions.


Subject(s)
Viral Proteins/genetics , Amino Acid Sequence , Molecular Sequence Data , Open Reading Frames , Sequence Homology, Amino Acid , Viral Proteins/chemistry
6.
PLoS One ; 8(11): e80720, 2013.
Article in English | MEDLINE | ID: mdl-24260463

ABSTRACT

We investigated whether small RNA (sRNA) sequenced from field-collected mosquitoes and chironomids (Diptera) can be used as a proxy signature of viral prevalence within a range of species and viral groups, using sRNAs sequenced from wild-caught specimens, to inform total RNA deep sequencing of samples of particular interest. Using this strategy, we sequenced from adult Anopheles maculipennis s.l. mosquitoes the apparently nearly complete genome of one previously undescribed virus related to chronic bee paralysis virus, and, from a pool of Ochlerotatus caspius and Oc. detritus mosquitoes, a nearly complete entomobirnavirus genome. We also reconstructed long sequences (1503-6557 nt) related to at least nine other viruses. Crucially, several of the sequences detected were reconstructed from host organisms highly divergent from those in which related viruses have been previously isolated or discovered. It is clear that viral transmission and maintenance cycles in nature are likely to be significantly more complex and taxonomically diverse than previously expected.


Subject(s)
Diptera/virology , Insect Viruses/classification , Insect Viruses/genetics , RNA, Viral , Animals , Base Sequence , Codon , Culicidae/virology , Entomobirnavirus/classification , Entomobirnavirus/genetics , Frameshift Mutation , Genome, Viral , Molecular Sequence Data , Phylogeny , Polymorphism, Genetic , Reading Frames , Reproducibility of Results , Sequence Alignment , Sequence Analysis, DNA , Untranslated Regions
7.
Virus Genes ; 47(3): 532-45, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23877720

ABSTRACT

We describe the isolation and characterization of an insect-specific flavivirus (ISF) from Ochlerotatus caspius (Pallas, 1771) mosquitoes collected in southern Portugal. The RNA genome of this virus, tentatively designated OCFVPT, for O. caspius flavivirus from Portugal, encodes a polyprotein showing all the features expected for a flavivirus. As frequently observed for ISF, the viral genomes seems to encode a putative Fairly Interesting Flavivirus ORF (FIFO)-like product, the synthesis of which would occur as a result of a -1 translation frameshift event. OCFVPT was isolated in the C6/36 Stegomyia albopicta (= Aedes albopictus) cell line where it replicates rapidly, but failed to replicate in Vero cells in common with other ISFs. Unlike some of the latter, however, the OCFVPT genome does not seem to be integrated in the mosquito cells we tested. Phylogenetic analyses based on partial ISF NS5 nucleotide sequences placed OCFVPT among recently published viral strains documented from mosquitoes collected in the Iberian Peninsula, while analyses of ORF/E/NS3/or NS5 amino acid sequences cluster OCFVPT with HANKV (Hanko virus), an ISF recently isolated from O. caspius mosquitoes collected in Finland. Taking into account the genetic relatedness with this virus, OCFVPT is not expected to be overtly cytopathic to C6/36 cells. The cytopathic effects associated with its presence in culture supernatants are postulated to be the result of the replication of a co-isolated putative new Negev-like virus.


Subject(s)
Culicidae/virology , Flavivirus/isolation & purification , Aedes , Animals , Flavivirus/classification , Flavivirus/genetics , Flavivirus/physiology , Genome, Viral , Molecular Sequence Data , Phylogeny , Portugal , Species Specificity , Virus Replication
8.
J Vector Ecol ; 37(2): 419-27, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23181867

ABSTRACT

Surveys of Anopheles mosquitoes were conducted in urban, rural, and natural areas of Tajikistan to obtain updated information on their distributions, especially in southern districts of the country where malaria is a prevalent disease. Nine species of Anopheles are found in Tajikistan. Anopheles superpictus, An. claviger, An. hyrcanus, and An. pulcherrimus are the most widespread and abundant species. Investigations in northern Tajikistan confirmed the presence of An. artemievi and the absence of An. martinius, both members of the An. maculipennis complex of malaria vectors. Anopheles barianensis, An. lindesayi, and An. marteri sogdianus, species previously recorded in the country, were not encountered during our surveys. The history of Anopheles and malaria research in Tajikistan is reviewed and bionomical and distributional information is provided for each of the nine species.


Subject(s)
Anopheles/physiology , Insect Vectors/physiology , Malaria/transmission , Animals , Anopheles/metabolism , Humans , Malaria/epidemiology , Molecular Sequence Data , Tajikistan/epidemiology
9.
Virology ; 433(2): 471-8, 2012 Nov 25.
Article in English | MEDLINE | ID: mdl-22999256

ABSTRACT

Mosquitoes collected in Finland were screened for flaviviral RNA leading to the discovery and isolation of a novel flavivirus designated Hanko virus (HANKV). Virus characterization, including phylogenetic analysis of the complete coding sequence, confirmed HANKV as a member of the "insect-specific" flavivirus (ISF) group. HANKV is the first member of this group isolated from northern Europe, and therefore the first northern European ISF for which the complete coding sequence has been determined. HANKV was not transcribed as DNA in mosquito cell culture, which appears atypical for an ISF. HANKV shared highest sequence homology with the partial NS5 sequence available for the recently discovered Spanish Ochlerotatus flavivirus (SOcFV). Retrospective analysis of mitochondrial sequences from the virus-positive mosquito pool suggested an Ochlerotatus mosquito species as the most likely host for HANKV. HANKV and SOcFV may therefore represent a novel group of Ochlerotatus-hosted insect-specific flaviviruses in Europe and further afield.


Subject(s)
Culicidae/virology , Flavivirus/classification , Flavivirus/isolation & purification , Animals , Finland , Flavivirus/genetics , Genome, Viral , Open Reading Frames , Phylogeny , RNA, Viral/genetics
10.
Virus Res ; 167(2): 152-61, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22579596

ABSTRACT

We describe the full genetic characterization of an insect-specific flavivirus (ISF) from Culex theileri (Theobald) mosquitoes collected in Portugal. This represents the first isolation and full characterization of an ISF from Portuguese mosquitoes. The virus, designated CTFV, for Culex theileri flavivirus, was isolated in the C6/36 Stegomyia albopicta (=Aedes albopictus) cell line, and failed to replicate in vertebrate (Vero) cells in common with other ISFs. The CTFV genome encodes a single polyprotein with 3357 residues showing all the features expected for those of flaviviruses. Phylogenetic analyses based on all ISF sequences available to date, place CTFV among Culex-associated flaviviruses, grouping with recently published NS5 partial sequences documented from mosquitoes collected in the Iberian Peninsula, and with Quang Binh virus (isolated in Vietnam) as a close relative. No CTFV sequences were found integrated in their host's genome using a range of specific PCR primers designed to the prM/E, NS3, and NS5 region.


Subject(s)
Culex/virology , Flavivirus/classification , Flavivirus/isolation & purification , Animals , Cell Line , Cluster Analysis , Flavivirus/genetics , Molecular Sequence Data , Open Reading Frames , Phylogeny , Polyproteins/genetics , Portugal , Sequence Analysis, DNA , Viral Proteins/genetics , Virus Cultivation
11.
J Gen Virol ; 93(Pt 2): 223-234, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22012464

ABSTRACT

There has been an explosion in the discovery of 'insect-specific' flaviviruses and/or their related sequences in natural mosquito populations. Herein we review all 'insect-specific' flavivirus sequences currently available and conduct phylogenetic analyses of both the 'insect-specific' flaviviruses and available sequences of the entire genus Flavivirus. We show that there is no statistical support for virus-mosquito co-divergence, suggesting that the 'insect-specific' flaviviruses may have undergone multiple introductions with frequent host switching. We discuss potential implications for the evolution of vectoring within the family Flaviviridae. We also provide preliminary evidence for potential recombination events in the history of cell fusing agent virus. Finally, we consider priorities and guidelines for future research on 'insect-specific' flaviviruses, including the vast potential that exists for the study of biodiversity within a range of potential hosts and vectors, and its effect on the emergence and maintenance of the flaviviruses.


Subject(s)
Evolution, Molecular , Flavivirus/genetics , Insecta/virology , Animals , Cluster Analysis , Flavivirus/classification , Flavivirus/isolation & purification , Phylogeny , RNA, Viral/genetics
12.
Infect Genet Evol ; 12(2): 332-44, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22197765

ABSTRACT

During the past three decades there has been a notable increase in dengue disease severity in Venezuela. Nevertheless, the population structure of the viruses being transmitted in this country is not well understood. Here, we present a molecular epidemiological study on dengue viruses (DENV) circulating in Aragua State, Venezuela during 2006-2007. Twenty-one DENV full-length genomes representing all of the four serotypes were amplified and sequenced directly from the serum samples. Notably, only DENV-2 was associated with severe disease. Phylogenetic trees constructed using Bayesian methods indicated that only one genotype was circulating for each serotype. However, extensive viral genetic diversity was found in DENV isolated from the same area during the same period, indicating significant in situ evolution since the introduction of these genotypes. Collectively, the results suggest that the non-structural (NS) proteins may play an important role in DENV evolution, particularly NS1, NS2A and NS4B proteins. The phylogenetic data provide evidence to suggest that multiple introductions of DENV have occurred from the Latin American region into Venezuela and vice versa. The implications of the significant viral genetic diversity generated during hyperendemic transmission, particularly in NS protein are discussed and considered in the context of future development and use of human monoclonal antibodies as antivirals and tetravalent vaccines.


Subject(s)
Dengue Virus/genetics , Dengue/epidemiology , Dengue/transmission , Dengue Virus/classification , Evolution, Molecular , Genetic Variation , Humans , Molecular Sequence Data , Phylogeny , Population/genetics , RNA, Viral/genetics , Sequence Analysis, DNA , Venezuela/epidemiology , Viral Proteins/genetics
13.
Vector Borne Zoonotic Dis ; 11(3): 277-84, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20925524

ABSTRACT

Yellow fever (YF) is a serious public health problem in Bolivia since at least the 19th century. Surprisingly, very limited information has been made available to date regarding the genetic characterisation and epidemiology of Bolivian YF virus (YFV) strains. Here, we conducted the genetic characterization of 12 human isolates of YFV collected in Bolivia between 1999 and 2008, by sequencing and analysis of two regions of the viral genome: a fragment encoding structural proteins "PrM" (premembrane and envelope) and a distal region "EMF," spanning the end of the virus genome. Our study reveals a high genetic diversity of YFV strains circulating in Bolivia during the last decade: we identified not only "Peruvian-like" genotype II viruses (related to previously characterized Bolivian strains), but also, for the fist time, "Brazilian-like" genotype I viruses. During the complete period of the study, only cases of "jungle" YF were detected (i.e., circulation of YFV via a sylvatic cycle) with no cluster of urban cases. However, the very significant spread of the Aedes aegypti mosquito across Bolivian cities threatens the country with the reappearance of an urban YFV transmission cycle and thus is required a sustained epidemiological surveillance.


Subject(s)
Aedes/virology , Insect Vectors/virology , Yellow Fever/epidemiology , Yellow fever virus/genetics , Adult , Animals , Biological Evolution , Bolivia/epidemiology , Female , Genetic Variation , Genotype , Humans , Male , Molecular Epidemiology , Phylogeny , Public Health , RNA, Viral/genetics , Sequence Analysis, DNA , Viral Envelope Proteins/genetics , Viral Proteins/genetics , Yellow Fever/transmission , Yellow Fever/virology , Yellow fever virus/isolation & purification , Young Adult
14.
J Gen Virol ; 91(Pt 5): 1275-83, 2010 May.
Article in English | MEDLINE | ID: mdl-20089800

ABSTRACT

Sandflies are widely distributed around the Mediterranean Basin. Therefore, human populations in this area are potentially exposed to sandfly-transmitted diseases, including those caused by phleboviruses. Whilst there are substantial data in countries located in the northern part of the Mediterranean basin, few data are available for North Africa. In this study, a total of 1489 sandflies were collected in 2008 in Tunisia from two sites, bioclimatically distinct, located 235 km apart, and identified morphologically. Sandfly species comprised Phlebotomus perniciosus (52.2%), Phlebotomus longicuspis (30.1%), Phlebotomus papatasi (12.0%), Phlebotomus perfiliewi (4.6%), Phlebotomus langeroni (0.4%) and Sergentomyia minuta (0.5%). PCR screening, using generic primers for the genus Phlebovirus, resulted in the detection of ten positive pools. Sequence analysis revealed that two pools contained viral RNA corresponding to a novel virus closely related to sandfly fever Naples virus. Virus isolation in Vero cells was achieved from one pool. Genetic and phylogenetic characterization based on sequences in the three genomic segments showed that it was a novel virus distinct from other recognized members of the species. This novel virus was provisionally named Punique virus. Viral sequences in the polymerase gene corresponding to another phlebovirus closely related to but distinct from sandfly fever Sicilian virus were obtained from the eight remaining positive pools.


Subject(s)
Phlebovirus/classification , Phlebovirus/isolation & purification , Psychodidae/virology , RNA, Viral/genetics , Animals , Chlorocebus aethiops , Cluster Analysis , Molecular Sequence Data , Phlebovirus/genetics , Phylogeny , RNA-Dependent RNA Polymerase/genetics , Sandfly fever Naples virus/genetics , Sequence Analysis, DNA , Sequence Homology , Tunisia , Vero Cells , Viral Proteins/genetics
15.
Antiviral Res ; 87(2): 125-48, 2010 Aug.
Article in English | MEDLINE | ID: mdl-19945487

ABSTRACT

Flaviviridae are small enveloped viruses hosting a positive-sense single-stranded RNA genome. Besides yellow fever virus, a landmark case in the history of virology, members of the Flavivirus genus, such as West Nile virus and dengue virus, are increasingly gaining attention due to their re-emergence and incidence in different areas of the world. Additional environmental and demographic considerations suggest that novel or known flaviviruses will continue to emerge in the future. Nevertheless, up to few years ago flaviviruses were considered low interest candidates for drug design. At the start of the European Union VIZIER Project, in 2004, just two crystal structures of protein domains from the flaviviral replication machinery were known. Such pioneering studies, however, indicated the flaviviral replication complex as a promising target for the development of antiviral compounds. Here we review structural and functional aspects emerging from the characterization of two main components (NS3 and NS5 proteins) of the flavivirus replication complex. Most of the reviewed results were achieved within the European Union VIZIER Project, and cover topics that span from viral genomics to structural biology and inhibition mechanisms. The ultimate aim of the reported approaches is to shed light on the design and development of antiviral drug leads.


Subject(s)
Enzymes/chemistry , Enzymes/metabolism , Flavivirus/enzymology , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/metabolism , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Biomedical Research/organization & administration , Biomedical Research/trends , Communicable Diseases, Emerging/epidemiology , Communicable Diseases, Emerging/virology , Drug Design , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Enzymes/genetics , European Union , Flavivirus/drug effects , Flavivirus Infections/epidemiology , Flavivirus Infections/virology , Humans , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/genetics , Virus Replication/drug effects
16.
Zootaxa ; 2661: 33-46, 2010 Oct 29.
Article in English | MEDLINE | ID: mdl-23155353

ABSTRACT

A new species of genus Bothaella (Diptera: Culicidae) collected along with two other species of the genus during surveys for flavivirus isolations in the Cuc Phuong National Park in northern Vietnam is formally described and named as Bothaella manhi, sp. n. The adults, pupa and fourth-instar larva are characterized, the male genitalia and the two immature stages are illustrated and DNA sequence data are included for regions coding for sections of the COI and COII genes (mtDNA). The species is compared and distinguished from the other species of the genus, and sequence data are used to hypothesise its phylogenetic relationship with Bo. helenae and Bo. kleini, the other two species collected during the survey.

17.
Vector Borne Zoonotic Dis ; 10(2): 195-7, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19492949

ABSTRACT

Sandfly-transmitted phleboviruses, such as Toscana, sandfly fever Sicilian, and sandfly fever Naples, can cause human disease and circulate at high rates in Mediterranean countries. Previous studies have also established that viruses other than phleboviruses may be detected in and isolated from sand flies. The recent detection and isolation (in a large variety of mosquito species) of insect-only flaviviruses related to cell fusing agent virus has indicated that the latter is not an evolutionary remnant but the first discovered member of a group of viruses, larger than initially assumed, that has high genetic heterogeneity. Insect-only flaviviruses have been detected in and/or isolated from various species of mosquitoes, but nevertheless only from mosquitoes to date; other dipterans have not been screened for the presence of insect-only flaviviruses. The possible presence of flaviviruses, including insect-only flaviviruses, was investigated in sand flies collected around the Mediterranean during a trapping campaign already underway. Accordingly, a total of 1508 sand flies trapped in France and Algeria, between August 2006 and July 2007, were tested for the presence of flaviviruses using a PCR assay previously demonstrated experimentally to amplify all recognized members of the genus Flavivirus, including insect-only flaviviruses. Two of 67 pools consisting of male Phlebotomus perniciosus trapped in Algeria were positive. The two resulting sequences formed a monophyletic group and appeared more closely related to insect-only flaviviruses associated with Culex mosquitoes than with Aedes mosquitoes, and more closely related to insect-only flaviviruses than to arthropod-borne or to no-known-vector vertebrate flaviviruses. This is the first description of insect-only flaviviruses in dipterans distinct from those belonging to the family Culicidae (including Aedes, Culex, Mansonia, Culiseta, and Anopheles mosquito genera), namely sand flies within the family Psychodidae. Accordingly, we propose their designation as phlebotomine-associated flaviviruses.


Subject(s)
Flavivirus/genetics , Flavivirus/isolation & purification , Phlebotomus/virology , RNA, Viral/genetics , RNA, Viral/isolation & purification , Algeria , Animals , France , Male , Phylogeny
18.
BMC Evol Biol ; 9: 298, 2009 Dec 22.
Article in English | MEDLINE | ID: mdl-20028549

ABSTRACT

BACKGROUND: Phylogenetic analyses provide a framework for examining the evolution of morphological and molecular diversity, interpreting patterns in biogeography, and achieving a stable classification. The generic and suprageneric relationships within mosquitoes (Diptera: Culicidae) are poorly resolved, making these subjects difficult to address. RESULTS: We carried out maximum parsimony and maximum likelihood, including Bayesian, analyses on a data set consisting of six nuclear genes and 80 morphological characters to assess their ability to resolve relationships among 25 genera. We also estimated divergence times based on sequence data and fossil calibration points, using Bayesian relaxed clock methods. Strong support was recovered for the basal position and monophyly of the subfamily Anophelinae and the tribes Aedini and Sabethini of subfamily Culicinae. Divergence times for major culicid lineages date to the early Cretaceous. CONCLUSIONS: Deeper relationships within the family remain poorly resolved, suggesting the need for additional taxonomic sampling. Our results support the notion of rapid radiations early in the diversification of mosquitoes.


Subject(s)
Culicidae/classification , Culicidae/genetics , Animals , Cell Nucleus/genetics , Culicidae/anatomy & histology , Evolution, Molecular , Phylogeny
19.
J Gen Virol ; 90(Pt 11): 2669-2678, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19656970

ABSTRACT

The genus Flavivirus, which contains approximately 70 single-stranded, positive-sense RNA viruses, represents a unique model for studying the evolution of vector-borne disease, as it includes viruses that are mosquito-borne, tick-borne or have no known vector. Both theoretical work and field studies suggest the existence of a large number of undiscovered flaviviruses. Recently, the first isolation of cell fusing agent virus (CFAV) was reported from a natural mosquito population in Puerto Rico, and sequences related to CFAV have been discovered in mosquitoes from Thailand. CFAV had previously been isolated from a mosquito cell line in 1975 and represented the only known 'insect-only' flavivirus, appearing to replicate in insect cells alone. A second member of the 'insect-only' group, Kamiti River virus (KRV), was isolated from Kenyan mosquitoes in 2003. A third tentative member of the 'insect-only' group, Culex flavivirus (CxFV), was first isolated in 2007 from Japan and further strains have subsequently been reported from the Americas. We report the discovery, isolation and characterization of two novel 'insect-only' flaviviruses from Entebbe, Uganda: a novel lineage tentatively designated Nakiwogo virus (NAKV) and a new strain of CxFV. The individual mosquitoes from which these strains were isolated, identified retrospectively by using a reference molecular phylogeny generated using voucher specimens from the region, were Mansonia africana nigerrima and Culex quinquefasciatus, respectively. This represents the first isolation, to our knowledge, of a novel insect-only flavivirus from a Mansonia species and the first isolation of a strain of CxFV from Africa.


Subject(s)
Culex/virology , Flavivirus/classification , Flavivirus/isolation & purification , Malvaceae/virology , RNA, Viral/genetics , Animals , Cluster Analysis , Flavivirus/genetics , Genotype , Microscopy, Electron, Transmission , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA , Sequence Homology , Uganda , Virion/ultrastructure
20.
Vector Borne Zoonotic Dis ; 9(3): 337-44, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19505253

ABSTRACT

Dengue fever was first recognized in Bolivia in 1931. However, very limited information was available to date regarding the genetic characterization and epidemiology of Bolivian dengue virus strains. Here, we performed genetic characterization of the full-length envelope gene of 64 Bolivian isolates from 1998 to 2008 and investigated their origin and evolution to determine whether strains circulated simultaneously or alternatively, and whether or not multiple introductions of distinct viral variants had occurred during the period studied. We determined that, during the last decade, closely related viruses circulated during several consecutive years (5, 6, and 6 years for DENV-1, DENV-2, and DENV-3, respectively) and the co-circulation of two or even three serotypes was observed. Emergence of new variants (distinct from those identified during the previous episodes) was identified in the case of DENV-1 (2007 outbreak) and DENV-2 (2001 outbreak). In all cases, it is likely that the viruses originated from neighboring countries.


Subject(s)
Dengue/epidemiology , Dengue/virology , Bolivia/epidemiology , Dengue Virus/classification , Dengue Virus/genetics , Humans , Molecular Epidemiology , Phylogeny , Time Factors
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