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1.
Cell ; 185(14): 2395-2397, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35803242

RESUMO

Flaviviruses, such as Dengue and Zika viruses, infect millions of people worldwide using mosquitos as vectors. In this issue of Cell, Zhang et al. reveal how these viruses manipulate the skin microbiome of infected hosts in a way that increases vector recruitment and viral spread. They propose vitamin A as a way to counteract the virus and decrease transmission.


Assuntos
Infecções por Flavivirus , Flavivirus , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pele , Animais , Culicidae/virologia , Dengue , Flavivirus/fisiologia , Infecções por Flavivirus/microbiologia , Infecções por Flavivirus/transmissão , Humanos , Publicações Periódicas como Assunto , Pele/metabolismo , Pele/microbiologia , Doenças Transmitidas por Vetores , Infecção por Zika virus
2.
Euro Surveill ; 27(25)2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35748300

RESUMO

BackgroundWest Nile virus (WNV) and Usutu virus (USUV), two closely related flaviviruses, mainly follow an enzootic cycle involving mosquitoes and birds, but also infect humans and other mammals. Since 2010, their epidemiological situation may have shifted from irregular epidemics to endemicity in several European regions; this requires confirmation, as it could have implications for risk assessment and surveillance strategies.AimTo explore the seroprevalence in animals and humans and potential endemicity of WNV and USUV in Southern France, given a long history of WNV outbreaks and the only severe human USUV case in France in this region.MethodsWe evaluated the prevalence of WNV and USUV in a repeated cross-sectional study by serological and molecular analyses of human, dog, horse, bird and mosquito samples in the Camargue area, including the city of Montpellier, between 2016 and 2020.ResultsWe observed the active transmission of both viruses and higher USUV prevalence in humans, dogs, birds and mosquitoes, while WNV prevalence was higher in horses. In 500 human samples, 15 were positive for USUV and 6 for WNV. Genetic data showed that the same lineages, WNV lineage 1a and USUV lineage Africa 3, were found in mosquitoes in 2015, 2018 and 2020.ConclusionThese findings support existing literature suggesting endemisation in the study region and contribute to a better understanding of USUV and WNV circulation in Southern France. Our study underlines the importance of a One Health approach for the surveillance of these viruses.


Assuntos
Culicidae , Infecções por Flavivirus , Saúde Única , Febre do Nilo Ocidental , Animais , Aves/virologia , Estudos Transversais , Culicidae/virologia , Cães/virologia , Flavivirus/genética , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/veterinária , França/epidemiologia , Cavalos/virologia , Humanos , Estudos Soroepidemiológicos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/genética
3.
Virol Sin ; 37(2): 229-237, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35527224

RESUMO

The Getah virus (GETV), a mosquito-borne RNA virus, is widely distributed in Oceania and Asia. GETV is not the only pathogenic to horses, pigs, cattle, foxes and boars, but it can also cause fever in humans. Since its first reported case in Chinese mainland in 2017, the number of GETV-affected provinces has increased to seventeen till now. Therefore, we performed an epidemiologic investigation of GETV in the Xinjiang region, located in northwestern China, during the period of 2017-2020. ELISA was used to analyze 3299 serum samples collected from thoroughbred horse, local horse, sheep, goat, cattle, and pigs, with thoroughbred horse (74.8%), local horse (67.3%), goat (11.7%), sheep (10.0%), cattle (25.1%) and pigs (51.1%) being positive for anti-GETV antibodies. Interestingly, the neutralizing antibody titer in horses was much higher than in other species. Four samples from horses and pigs were positive for GETV according to RT-PCR. Furthermore, from the serum of a local horse, we isolated GETV which was designated as strain XJ-2019-07, and determined its complete genome sequence. From the phylogenetic relationships, it belongs to the Group III lineage. This is the first evidence of GETV associated to domestic animals in Xinjiang. Overall, GETV is prevalent in Xinjiang and probably has been for several years. Since no vaccine against GETV is available in China, detection and monitoring strategies should be improved in horses and pigs, especially imported and farmed, in order to prevent economic losses.


Assuntos
Alphavirus , Culicidae , Alphavirus/genética , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Bovinos/virologia , China/epidemiologia , Culicidae/virologia , Cabras/virologia , Cavalos/virologia , Masculino , Filogenia , Análise de Sequência de DNA , Estudos Soroepidemiológicos , Ovinos/virologia , Suínos/virologia
4.
PLoS Negl Trop Dis ; 16(2): e0010186, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35176020

RESUMO

BACKGROUND: In Greece vector borne diseases (VBD) and foremost West Nile virus (WNV) pose an important threat to public health and the tourist industry, the primary sector of contribution to the national economy. The island of Crete, is one of Greece's major tourist destinations receiving annually over 5 million tourists making regional VBD control both a public health and economic priority. METHODOLOGY: Under the auspices of the Region of Crete, a systematic integrative surveillance network targeting mosquitoes and associated pathogens was established in Crete for the years 2018-2020. Using conventional and molecular diagnostic tools we investigated the mosquito species composition and population dynamics, pathogen infection occurrences in vector populations and in sentinel chickens, and the insecticide resistance status of the major vector species. PRINCIPAL FINDINGS: Important disease vectors were recorded across the island including Culex pipiens, Aedes albopictus, and Anopheles superpictus. Over 75% of the sampled specimens were collected in the western prefectures potentially attributed to the local precipitation patterns, with Cx. pipiens being the most dominant species. Although no pathogens (flaviviruses) were detected in the analysed mosquito specimens, chicken blood serum analyses recorded a 1.7% WNV antibody detection rate in the 2018 samples. Notably detection of the first WNV positive chicken preceded human WNV occurrence in the same region by approximately two weeks. The chitin synthase mutation I1043F (associated with high diflubenzuron resistance) was recorded at an 8% allelic frequency in Lasithi prefecture Cx. pipiens mosquitoes (sampled in 2020) for the first time in Greece. Markedly, Cx. pipiens populations in all four prefectures were found harboring the kdr mutations L1014F/C/S (associated with pyrethroid resistance) at a close to fixation rate, with mutation L1014C being the most commonly found allele (≥74% representation). Voltage gated sodium channel analyses in Ae. albopictus revealed the presence of the kdr mutations F1534C and I1532T (associated with putative mild pyrethroid resistance phenotypes) yet absence of V1016G. Allele F1534C was recorded in all prefectures (at an allelic frequency range of 25-46.6%) while I1532T was detected in populations from Chania, Rethymnon and Heraklion (at frequencies below 7.1%). Finally, no kdr mutations were detected in the Anopheles specimens included in the analyses. CONCLUSIONS/SIGNIFICANCE: The findings of our study are of major concern for VBD control in Crete, highlighting (i) the necessity for establishing seasonal integrated entomological/pathogen surveillance programs, supporting the design of targeted vector control responses and; ii) the need for establishing appropriate insecticide resistance management programs ensuring the efficacy and sustainable use of DFB and pyrethroid based products in vector control.


Assuntos
Culicidae/efeitos dos fármacos , Resistência a Inseticidas , Inseticidas/farmacologia , Mosquitos Vetores/efeitos dos fármacos , Doenças Transmitidas por Vetores/veterinária , Doenças Transmitidas por Vetores/virologia , Febre do Nilo Ocidental/veterinária , Febre do Nilo Ocidental/virologia , Animais , Galinhas , Culicidae/classificação , Culicidae/fisiologia , Culicidae/virologia , Diflubenzuron/farmacologia , Grécia , Humanos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Mosquitos Vetores/fisiologia , Mutação , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Piretrinas/farmacologia , Doenças Transmitidas por Vetores/transmissão , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/isolamento & purificação , Vírus do Nilo Ocidental/fisiologia
5.
Viruses ; 14(2)2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35216028

RESUMO

Emerging and re-emerging mosquito-borne viral diseases impose a significant burden on global public health. The most common mosquito-borne viruses causing recent epidemics include flaviviruses in the family Flaviviridae, including Dengue virus (DENV), Zika virus (ZIKV), Japanese encephalitis virus (JEV) and West Nile virus (WNV) and Togaviridae viruses, such as chikungunya virus (CHIKV). Several factors may have contributed to the recent re-emergence and spread of mosquito-borne viral diseases. Among these important causes are the evolution of mosquito-borne viruses and the genetic mutations that make them more adaptive and virulent, leading to widespread epidemics. RNA viruses tend to acquire genetic diversity due to error-prone RNA-dependent RNA polymerases, thus promoting high mutation rates that support adaptation to environmental changes or host immunity. In this review, we discuss recent findings on the adaptive evolution of mosquito-borne viruses and their impact on viral infectivity, pathogenicity, vector fitness, transmissibility, epidemic potential and disease emergence.


Assuntos
Culicidae/virologia , Flavivirus/fisiologia , Mosquitos Vetores/virologia , Doenças Transmitidas por Vetores/virologia , Animais , Evolução Biológica , Culicidae/imunologia , Epidemias , Flavivirus/classificação , Flavivirus/imunologia , Humanos , Replicação Viral
6.
Virology ; 568: 49-55, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35114499

RESUMO

West Nile virus (WNV) overwintering is poorly understood and likely multifactorial. Interest in alligators as a potential amplifying host arose when it was shown that they develop viremias theoretically sufficient to infect mosquitoes. We examined potential ways in which alligators may contribute to the natural ecology of WNV. We experimentally demonstrated that alligators are capable of WNV amplification with subsequent mosquito infection and transmission capability, that WNV-infected mosquitoes readily infect alligators and that water can serve as a source of infection for alligators but does not easily serve as in intermediate means for transmission between birds and alligators. These findings indicate potential mechanisms for maintenance of WNV outside of the primary bird-mosquito transmission cycle.


Assuntos
Jacarés e Crocodilos/virologia , Culicidae/virologia , Mosquitos Vetores/virologia , Replicação Viral , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/fisiologia , Animais , Aves/virologia , Chlorocebus aethiops , Reservatórios de Doenças/virologia , Células Vero , Zoonoses Virais , Febre do Nilo Ocidental/virologia
7.
J Virol ; 96(5): e0166421, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-34986002

RESUMO

The dengue virus NS1 is a multifunctional protein that forms part of replication complexes. NS1 is also secreted, as a hexamer, to the extracellular milieu. Circulating NS1 has been associated with dengue pathogenesis by several mechanisms. Cell binding and internalization of soluble NS1 result in endothelial hyperpermeability and in the downregulation of the innate immune response. In this work, we report that the HDL scavenger receptor B1 (SRB1) in human hepatic cells and a scavenger receptor B1-like in mosquito C6/36 cells act as cell surface binding receptors for dengue virus NS1. The presence of the SRB1 on the plasma membrane of C6/36 cells, as well as in Huh7 cells, was demonstrated by confocal microscopy. The internalization of NS1 can be efficiently blocked by anti-SRB1 antibodies, and previous incubation of the cells with HDL significantly reduces NS1 internalization. Significant reduction in NS1 internalization was observed in C6/36 cells transfected with siRNAs specific for SRB1. In addition, the transient expression of SRB1 in Vero cells, which lacks the receptor, allows NS1 internalization in these cells. Direct interaction between soluble NS1 and the SRB1 in Huh7 and C6/36 cells was demonstrated in situ by proximity ligation assays and in vitro by surface plasmon resonance. Finally, results are presented indicating that the SRB1 also acts as a cell receptor for Zika virus NS1. These results demonstrate that dengue virus NS1, a bona fide lipoprotein, usurps the HDL receptor for cell entry and offers explanations for the altered serum lipoprotein homeostasis observed in dengue patients. IMPORTANCE Dengue is the most common viral disease transmitted to humans by mosquitoes. The dengue virus NS1 is a multifunctional glycoprotein necessary for viral replication. NS1 is also secreted as a hexameric lipoprotein and circulates in high concentrations in the sera of patients. Circulating NS1 has been associated with dengue pathogenesis by several mechanisms, including favoring of virus replication in hepatocytes and dendritic cells and disruption of the endothelial glycocalyx leading to hyperpermeability. Those last actions require NS1 internalization. Here, we identify the scavenger cell receptor B1, as the cell-binding receptor for dengue and Zika virus NS1, in cultured liver and in mosquito cells. The results indicate that flavivirus NS1, a bona fide lipoprotein, usurps the human HDL receptor and may offer explanations for the alterations in serum lipoprotein homeostasis observed in dengue patients.


Assuntos
Vírus da Dengue , Receptores Depuradores , Proteínas não Estruturais Virais , Infecção por Zika virus , Zika virus , Animais , Linhagem Celular , Chlorocebus aethiops , Culicidae/virologia , Dengue/virologia , Vírus da Dengue/metabolismo , Humanos , Lipoproteínas HDL , Receptores de Lipoproteínas , Receptores Depuradores/metabolismo , Células Vero , Proteínas não Estruturais Virais/imunologia , Internalização do Vírus , Zika virus/metabolismo
8.
Am J Trop Med Hyg ; 106(2): 610-622, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35008051

RESUMO

Mosquitoes were collected for 12 consecutive months beginning June 2016, from 11 locations in the Florida Everglades, Collier County, and tested for viruses by isolation in Vero cells and subsequent identification. One species complex and 31 species of mosquitoes were identified from 668,809 specimens. Ochlerotatus taeniorhynchus comprised 72.2% of the collection. Other notable species were Anopheles crucians complex, Culex nigripalpus, Cx. erraticus, and Cx. cedecei. Seven species of virus were identified from 110 isolations: Everglades, Gumbo Limbo, Mahogany Hammock, Pahayokee, Shark River, Tensaw, and West Nile viruses. Everglades, West Nile, Tensaw, and Mahogany Hammock viruses were most frequently isolated. Largest numbers of viruses were identified from Cx. cedecei, Cx. nigripalpus, and An. crucians complex. Five species of virus were isolated from Cx. cedecei. Viruses were isolated from mangrove, cypress swamp, hardwood hammock, and sawgrass habitats. West Nile virus was isolated August through October when Cx. nigripalpus was most abundant. Everglades virus was the most frequently isolated virus from nine species of mosquitoes collected from June through August. Tensaw virus was isolated primarily from Anopheles species. Isolations were made in July, August, January, February, and April, suggesting that this virus may be present in host-seeking mosquitoes throughout the year. Mahogany Hammock, Shark River, Gumbo Limbo, and Pahayokee viruses were isolated primarily from Cx. cedecei from June through December. Shotgun metagenomic sequencing was used to document that seven pools of Cx. cedecei were infected with two arboviruses. As communities expand into the Everglades, more humans will become exposed to arboviruses.


Assuntos
Culicidae/classificação , Culicidae/virologia , Mosquitos Vetores/classificação , Mosquitos Vetores/virologia , RNA Viral/isolamento & purificação , Doenças Transmitidas por Vetores/virologia , Viroses/classificação , Animais , Ecossistema , Florida , Filogenia , Estações do Ano
9.
PLoS Negl Trop Dis ; 16(1): e0010145, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35100289

RESUMO

Southern Russia remains affected by West Nile virus (WNV). In the current study, we identified the spatial determinants of WNV distribution in an area with endemic virus transmission, with special reference to the urban settings, by mapping probable points of human infection acquisition and points of virus detection in mosquitoes, ticks, birds, and mammals during 1999-2016. The suitability of thermal conditions for extrinsic virus replication was assessed based on the approach of degree-day summation and their changes were estimated by linear trend analysis. A generalized linear model was used to analyze the year-to-year variation of human cases versus thermal conditions. Environmental suitability was determined by ecological niche modelling using MaxEnt software. Human population density was used as an offset to correct for possible bias. Spatial analysis of virus detection in the environment showed significant contributions from surface temperature, altitude, and distance from water bodies. When indicators of location and mobility of the human population were included, the relative impact of factors changed, with roads becoming most important. When the points of probable human case infection were added, the percentage of leading factors changed only slightly. The urban environment significantly increased the epidemic potential of the territory and created quite favorable conditions for virus circulation. The private building sector with low-storey houses and garden plots located in the suburbs provided a connection between urban and rural transmission cycles.


Assuntos
Aves/virologia , Culicidae/virologia , Carrapatos/virologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/transmissão , Aedes/classificação , Aedes/virologia , Animais , Anopheles/classificação , Anopheles/virologia , Argasidae/virologia , Culex/classificação , Culex/virologia , Meio Ambiente , Geografia , Humanos , Ixodidae/virologia , Densidade Demográfica , Federação Russa/epidemiologia , Análise Espacial , Temperatura , Vírus do Nilo Ocidental/isolamento & purificação
10.
Parasit Vectors ; 15(1): 23, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35012637

RESUMO

BACKGROUND: Yellow fever virus (YFV) is an arbovirus that, despite the existence of a safe and effective vaccine, continues to cause outbreaks of varying dimensions in the Americas and Africa. Between 2017 and 2019, Brazil registered un unprecedented sylvatic YFV outbreak whose severity was the result of its spread into zones of the Atlantic Forest with no signals of viral circulation for nearly 80 years. METHODS: To investigate the influence of climatic, environmental, and ecological factors governing the dispersion and force of infection of YFV in a naïve area such as the landscape mosaic of Rio de Janeiro (RJ), we combined the analyses of a large set of data including entomological sampling performed before and during the 2017-2019 outbreak, with the geolocation of human and nonhuman primates (NHP) and mosquito infections. RESULTS: A greater abundance of Haemagogus mosquitoes combined with lower richness and diversity of mosquito fauna increased the probability of finding a YFV-infected mosquito. Furthermore, the analysis of functional traits showed that certain functional groups, composed mainly of Aedini mosquitoes which includes Aedes and Haemagogus mosquitoes, are also more representative in areas where infected mosquitoes were found. Human and NHP infections were more common in two types of landscapes: large and continuous forest, capable of harboring many YFV hosts, and patches of small forest fragments, where environmental imbalance can lead to a greater density of the primary vectors and high human exposure. In both, we show that most human infections (~ 62%) occurred within an 11-km radius of the finding of an infected NHP, which is in line with the flight range of the primary vectors. CONCLUSIONS: Together, our data suggest that entomological data and landscape composition analyses may help to predict areas permissive to yellow fever outbreaks, allowing protective measures to be taken to avoid human cases.


Assuntos
Brasil , Culicidae , Surtos de Doenças , Mosquitos Vetores , Febre Amarela/transmissão , Aedes/crescimento & desenvolvimento , Aedes/virologia , Animais , Biodiversidade , Brasil/epidemiologia , Clima , Culicidae/crescimento & desenvolvimento , Culicidae/virologia , Florestas , Humanos , Mosquitos Vetores/classificação , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/virologia , Fatores de Risco , Febre Amarela/epidemiologia
11.
PLoS Negl Trop Dis ; 16(1): e0010019, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34995277

RESUMO

BACKGROUND: Yellow fever (YF) is an arboviral disease which is endemic to Brazil due to a sylvatic transmission cycle maintained by infected mosquito vectors, non-human primate (NHP) hosts, and humans. Despite the existence of an effective vaccine, recent sporadic YF epidemics have underscored concerns about sylvatic vector surveillance, as very little is known about their spatial distribution. Here, we model and map the environmental suitability of YF's main vectors in Brazil, Haemagogus spp. and Sabethes spp., and use human population and NHP data to identify locations prone to transmission and spillover risk. METHODOLOGY/PRINCIPAL FINDINGS: We compiled a comprehensive set of occurrence records on Hg. janthinomys, Hg. leucocelaenus, and Sabethes spp. from 1991-2019 using primary and secondary data sources. Linking these data with selected environmental and land-cover variables, we adopted a stacked regression ensemble modelling approach (elastic-net regularized GLM, extreme gradient boosted regression trees, and random forest) to predict the environmental suitability of these species across Brazil at a 1 km x 1 km resolution. We show that while suitability for each species varies spatially, high suitability for all species was predicted in the Southeastern region where recent outbreaks have occurred. By integrating data on NHP host reservoirs and human populations, our risk maps further highlight municipalities within the region that are prone to transmission and spillover. CONCLUSIONS/SIGNIFICANCE: Our maps of sylvatic vector suitability can help elucidate potential locations of sylvatic reservoirs and be used as a tool to help mitigate risk of future YF outbreaks and assist in vector surveillance. Furthermore, at-risk regions identified from our work could help disease control and elucidate gaps in vaccination coverage and NHP host surveillance.


Assuntos
Culicidae/virologia , Mosquitos Vetores/virologia , Febre Amarela/transmissão , Vírus da Febre Amarela/fisiologia , Animais , Brasil/epidemiologia , Interações Hospedeiro-Patógeno , Especificidade da Espécie , Febre Amarela/epidemiologia , Febre Amarela/virologia
13.
J Virol ; 96(2): e0177421, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34757841

RESUMO

Alphaviruses and flaviviruses have class II fusion glycoproteins that are essential for virion assembly and infectivity. Importantly, the tip of domain II is structurally conserved between the alphavirus and flavivirus fusion proteins, yet whether these structural similarities between virus families translate to functional similarities is unclear. Using in vivo evolution of Zika virus (ZIKV), we identified several novel emerging variants, including an envelope glycoprotein variant in ß-strand c (V114M) of domain II. We have previously shown that the analogous ß-strand c and the ij loop, located in the tip of domain II of the alphavirus E1 glycoprotein, are important for infectivity. This led us to hypothesize that flavivirus E ß-strand c also contributes to flavivirus infection. We generated this ZIKV glycoprotein variant and found that while it had little impact on infection in mosquitoes, it reduced replication in human cells and mice and increased virus sensitivity to ammonium chloride, as seen for alphaviruses. In light of these results and given our alphavirus ij loop studies, we mutated a conserved alanine at the tip of the flavivirus ij loop to valine to test its effect on ZIKV infectivity. Interestingly, this mutation inhibited infectious virion production of ZIKV and yellow fever virus, but not West Nile virus. Together, these studies show that shared domains of the alphavirus and flavivirus class II fusion glycoproteins harbor structurally analogous residues that are functionally important and contribute to virus infection in vivo. IMPORTANCE Arboviruses are a significant global public health threat, yet there are no antivirals targeting these viruses. This problem is in part due to our lack of knowledge of the molecular mechanisms involved in the arbovirus life cycle. In particular, virus entry and assembly are essential processes in the virus life cycle and steps that can be targeted for the development of antiviral therapies. Therefore, understanding common, fundamental mechanisms used by different arboviruses for entry and assembly is essential. In this study, we show that flavivirus and alphavirus residues located in structurally conserved and analogous regions of the class II fusion proteins contribute to common mechanisms of entry, dissemination, and infectious-virion production. These studies highlight how class II fusion proteins function and provide novel targets for development of antivirals.


Assuntos
Alphavirus/fisiologia , Flavivirus/fisiologia , Proteínas Virais de Fusão/metabolismo , Vírion/metabolismo , Replicação Viral , Células A549 , Alphavirus/efeitos dos fármacos , Cloreto de Amônio/farmacologia , Animais , Culicidae/virologia , Flavivirus/efeitos dos fármacos , Humanos , Interferon Tipo I/deficiência , Camundongos , Camundongos Mutantes , Mutação , Domínios Proteicos , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/genética , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Vírion/genética , Montagem de Vírus/genética , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/genética , Zika virus/efeitos dos fármacos , Zika virus/fisiologia , Infecção por Zika virus/virologia
14.
Nucleic Acids Res ; 50(D1): D943-D949, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34634795

RESUMO

Emerging infectious diseases significantly threaten global public health and socioeconomic security. The majority of emerging infectious disease outbreaks are caused by zoonotic/vector-borne viruses. Bats and rodents are the two most important reservoir hosts of many zoonotic viruses that can cross species barriers to infect humans, whereas mosquitos and ticks are well-established major vectors of many arboviral diseases. Moreover, some emerging zoonotic diseases require a vector to spread or are intrinsically vector-borne and zoonotically transmitted. In this study, we present a newly upgraded database of zoonotic and vector-borne viruses designated ZOVER (http://www.mgc.ac.cn/ZOVER). It incorporates two previously released databases, DBatVir and DRodVir, for bat- and rodent-associated viruses, respectively, and further collects up-to-date knowledge on mosquito- and tick-associated viruses to establish a comprehensive online resource for zoonotic and vector-borne viruses. Additionally, it integrates a set of online visualization tools for convenient comparative analyses to facilitate the discovery of potential patterns of virome diversity and ecological characteristics between/within different viral hosts/vectors. The ZOVER database will be a valuable resource for virologists, zoologists and epidemiologists to better understand the diversity and dynamics of zoonotic and vector-borne viruses and conduct effective surveillance to monitor potential interspecies spillover for efficient prevention and control of future emerging zoonotic diseases.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Bases de Dados Factuais , Software , Viroses/epidemiologia , Vírus/patogenicidade , Zoonoses/epidemiologia , Animais , Quirópteros/virologia , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/virologia , Culicidae/virologia , Conjuntos de Dados como Assunto , Vetores de Doenças/classificação , Monitoramento Epidemiológico , Interações Hospedeiro-Patógeno , Humanos , Internet , Anotação de Sequência Molecular , Roedores/virologia , Carrapatos/virologia , Viroses/transmissão , Viroses/virologia , Vírus/classificação , Vírus/genética , Zoonoses/transmissão , Zoonoses/virologia
15.
J Med Virol ; 94(2): 776-781, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34664719

RESUMO

We describe the circulation of Saint Louis encephalitis virus (SLEV) in two Brazilian States during outbreaks of Dengue and Zika viruses. We detected the virus in a patient from Araraquara, State of São Paulo, and in patients and in a mosquito pool of Culex quinquefasciatus from Sinop, State of Mato Grosso. Phylogenetic analysis grouped samples from this study within genotype V, which are closely related to other strains that previously circulated in other parts of the country. Genotype V seems to have established circulation in Brazil.


Assuntos
Culicidae/virologia , Vírus da Encefalite de St. Louis/genética , Encefalite de St. Louis/virologia , Genótipo , Adolescente , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Dengue/epidemiologia , Surtos de Doenças , Vírus da Encefalite de St. Louis/isolamento & purificação , Feminino , Humanos , Lactente , Masculino , Filogenia , Infecção por Zika virus/epidemiologia
16.
Sci Rep ; 11(1): 23489, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34873243

RESUMO

The stress of the Golgi apparatus is an autoregulatory mechanism that is induced to compensate for greater demand in the Golgi functions. No examples of Golgi stress responses due to physiological stimuli are known. Furthermore, the impact on this organelle of viral infections that occupy the vesicular transport during replication is unknown. In this work, we evaluated if a Golgi stress response is triggered during dengue and Zika viruses replication, two flaviviruses whose replicative cycle is heavily involved with the Golgi complex, in vertebrate and mosquito cells. Using GM-130 as a Golgi marker, and treatment with monensin as a positive control for the induction of the Golgi stress response, a significant expansion of the Golgi cisternae was observed in BHK-21, Vero E6 and mosquito cells infected with either virus. Activation of the TFE3 pathway was observed in the infected cells as indicated by the translocation from the cytoplasm to the nucleus of TFE3 and increased expression of pathway targeted genes. Of note, no sign of activation of the stress response was observed in CRFK cells infected with Feline Calicivirus (FCV), a virus released by cell lysis, not requiring vesicular transport. Finally, dilatation of the Golgi complex and translocation of TFE3 was observed in vertebrate cells expressing dengue and Zika viruses NS1, but not NS3. These results indicated that infections by dengue and Zika viruses induce a Golgi stress response in vertebrate and mosquito cells due to the increased demand on the Golgi complex imposed by virion and NS1 processing and secretion.


Assuntos
Culicidae/virologia , Infecções por Flavivirus/virologia , Flavivirus/genética , Complexo de Golgi/virologia , Vertebrados/virologia , Animais , Células Cultivadas , Chlorocebus aethiops , Mesocricetus , Células Vero , Proteínas não Estruturais Virais/genética , Replicação Viral/genética
17.
Viruses ; 13(12)2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34960732

RESUMO

Mosquitoes collected from mid-December 2020 to early March 2021 from hibernacula in northeastern Germany, a region of West Nile virus (WNV) activity since 2018, were examined for WNV-RNA. Among the 6101 mosquitoes tested in 722 pools of up to 12 specimens, one pool of 10 Culex pipiens complex mosquitoes collected in early March 2021 in the cellar of a medieval castle in Rosslau, federal state of Saxony-Anhalt, tested positive. Subsequent mosquito DNA analysis produced Culex pipiens biotype pipiens. The pool homogenate remaining after nucleic acid extraction failed to grow the virus on Vero and C6/36 cells. Sequencing of the viral NS2B-NS3 coding region, however, demonstrated high homology with virus strains previously collected in Germany, e.g., from humans, birds, and mosquitoes, which have been designated the East German WNV clade. The finding confirms the expectation that WNV can overwinter in mosquitoes in Germany, facilitating an early start to the natural transmission season in the subsequent year. On the other hand, the calculated low infection prevalence of 0.016-0.20%, depending on whether one or twelve of the mosquitoes in the positive pool was/were infected, indicates a slow epidemic progress and mirrors the still-hypoendemic situation in Germany. In any case, local overwintering of the virus in mosquitoes suggests its long-term persistence and an enduring public health issue.


Assuntos
Culicidae/virologia , Mosquitos Vetores/virologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Culicidae/classificação , Culicidae/fisiologia , Alemanha , Humanos , Mosquitos Vetores/classificação , Mosquitos Vetores/fisiologia , Estações do Ano , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genética
18.
PLoS One ; 16(12): e0261244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34941927

RESUMO

Arboviruses are arthropod-dependent viruses to complete their zoonotic cycle. Among the transmitting arthropods, culicids stand out, which participate in the cycle of several arboviruses that can affect humans. The present study aimed to identify species of culicidae and to point out the risk of circulation, emergency, or reemergence of pathogenic arboviruses to humans in the region of the Jequitibá headquarters of the Parque Estadual dos Três Picos (PETP), in Cachoeiras de Macacu, state of Rio de Janeiro, Brazil. Sampling was carried out at five Sample Points (SP) demarcated on trails from the headquarters, with CDC light traps, HP model with dry ice attached to the side, for 48 hours of activity each month. Additionally, active catches were made with a castro catcher in the period of one hour per day in the field, from six to eleven o'clock in the morning, in each PM. After the captures, thematic map was assembled using the ArcGIS 10 software and performing a multidimensional scaling (MDS). A total of 1151 specimens were captured and the presence of culicids already incriminated as vectors of arboviruses circulating in the region was observed: Aedes fluviatilis Lutz, 1904 (71 specimens); Aedes scapularis Rondani, 1848 (55 specimens); Haemagogus leococelaenus Dyar and Shannon, 1924 (29 specimens). In addition to the subgenus Culex (culex) spp. (163 specimens). In this sense, we highlight the importance of strengthening the actions of continuous entomological surveillance of the emergence and re-emergence of new arboviruses in ecotourism visitation parks.


Assuntos
Infecções por Arbovirus/epidemiologia , Culicidae/virologia , Aedes/virologia , Animais , Arbovírus/patogenicidade , Brasil/epidemiologia , Dípteros/patogenicidade , Monitoramento Epidemiológico/veterinária , Mosquitos Vetores/virologia , Estações do Ano , Vigilância de Evento Sentinela/veterinária
19.
PLoS One ; 16(12): e0261283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34898653

RESUMO

The present study aims to analyze the effectiveness of ovitraps in the capture of Hg leucocelaenus eggs and evaluate the influence of the dry and rainy seasons on their abundance and hatching rates. The eggs were collected in the Atlantic Forest of State of Rio de Janeiro, Brazil, an area in which the yellow fever virus is known to circulate. We distributed 15 ovitraps in three sampling points, with five ovitraps per point. We distributed 15 ovitraps in three sampling points on trees within a forested area, which were sequentially numbered, monitored, and replaced every two weeks from October 2016 to April 2018. There was a high dominance of Hg. leucocelaenus eggs (98.4%) and a variation in egg hatching rates between the wet and dry seasons. These rates were 1.5 times higher in the rainy season than in the dry season. The rainy season also showed a greater abundance of eggs and higher values of ovitrap positivity and egg density indexes in the installed ovitraps. The abundances of Hg. leucocelaenus eggs were positively correlated with mean monthly temperature and air humidity but not significantly correlated with accumulated precipitation. These results, as well as their implications for the possible use of ovitraps to monitor vector mosquitoes of yellow fever in the study region, are discussed.


Assuntos
Culicidae/metabolismo , Oviposição/fisiologia , Animais , Brasil , Culicidae/fisiologia , Culicidae/virologia , Secas , Florestas , Insetos Vetores , Mosquitos Vetores , Densidade Demográfica , Chuva , Estações do Ano , Temperatura , Árvores , Febre Amarela/epidemiologia , Febre Amarela/transmissão , Vírus da Febre Amarela/patogenicidade
20.
Viruses ; 13(11)2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34834923

RESUMO

Mosquito-borne viruses of the Flavivirus genus (Flaviviridae family) pose an ongoing threat to global public health. For example, dengue, Japanese encephalitis, West Nile, yellow fever, and Zika viruses are transmitted by infected mosquitoes and cause severe and fatal diseases in humans. The means by which mosquito-borne flaviviruses establish persistent infection in mosquitoes and cause disease in humans are complex and depend upon a myriad of virus-host interactions, such as those of the innate immune system, which are the main focus of our review. This review also covers the different strategies utilized by mosquito-borne flaviviruses to antagonize the innate immune response in humans and mosquitoes. Given the lack of antiviral therapeutics for mosquito-borne flaviviruses, improving our understanding of these virus-immune interactions could lead to new antiviral therapies and strategies for developing refractory vectors incapable of transmitting these viruses, and can also provide insights into determinants of viral tropism that influence virus emergence into new species.


Assuntos
Culicidae/imunologia , Infecções por Flavivirus/imunologia , Infecções por Flavivirus/veterinária , Flavivirus/imunologia , Infecção Persistente/imunologia , Infecção Persistente/veterinária , Animais , Culicidae/fisiologia , Culicidae/virologia , Flavivirus/genética , Flavivirus/fisiologia , Infecções por Flavivirus/transmissão , Infecções por Flavivirus/virologia , Humanos , Imunidade Inata , Mosquitos Vetores/imunologia , Mosquitos Vetores/fisiologia , Mosquitos Vetores/virologia , Infecção Persistente/virologia
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