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Open AccessEditorial

Special Issue “Transmission Dynamics of Insect Viruses”

by Kenneth A. Stapleford

Viruses 2020, 12(6), 644; https://doi.org/10.3390/v12060644 - 14 Jun 2020

Viewed by 1915

Abstract

At the close of this Special Issue of Viruses on the Transmission Dynamics of Insect Viruses, we would like to thank all of the authors for their submissions and the great work expanding our knowledge of insect virus biology and transmission [...] Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

Research

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11 pages, 2034 KiB

Open AccessArticle

Measuring Alphavirus Fidelity Using Non-Infectious Virus Particles

by Edward I. Patterson, Kamil Khanipov, Daniele M. Swetnam, Samantha Walsdorf, Tiffany F. Kautz, Saravanan Thangamani, Yuriy Fofanov and Naomi L. Forrester

Viruses 2020, 12(5), 546; https://doi.org/10.3390/v12050546 - 15 May 2020

Cited by 6 | Viewed by 3408

Abstract

Mutations are incorporated into the genomes of RNA viruses at an optimal frequency and altering this precise frequency has been proposed as a strategy to create live-attenuated vaccines. However, determining the effect of specific mutations that alter fidelity has been difficult because of [...] Read more.

Mutations are incorporated into the genomes of RNA viruses at an optimal frequency and altering this precise frequency has been proposed as a strategy to create live-attenuated vaccines. However, determining the effect of specific mutations that alter fidelity has been difficult because of the rapid selection of the virus population during replication. By deleting residues of the structural polyprotein PE2 cleavage site, E3Δ56-59, in Venezuelan equine encephalitis virus (VEEV) TC-83 vaccine strain, non-infectious virus particles were used to assess the effect of single mutations on mutation frequency without the interference of selection that results from multiple replication cycles. Next-generation sequencing analysis revealed a significantly lower frequency of transversion mutations and overall mutation frequency for the fidelity mutants compared to VEEV TC-83 E3Δ56-59. We demonstrate that deletion of the PE2 cleavage site halts virus infection while making the virus particles available for downstream sequencing. The conservation of the site will allow the evaluation of suspected fidelity mutants across alphaviruses of medical importance. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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8 pages, 705 KiB

Open AccessArticle

Circulation of Toscana Virus in a Sample Population of Corsica, France

by Shirley Masse, Nazli Ayhan, Lisandru Capai, Frédéric Bosseur, Xavier de Lamballerie, Rémi Charrel and Alessandra Falchi

Viruses 2019, 11(9), 817; https://doi.org/10.3390/v11090817 - 4 Sep 2019

Cited by 9 | Viewed by 4076

Abstract

Sandfly-borne phleboviruses pathogenic to humans, such as Toscana virus (TOSV) and Sandfly Fever Sicilian virus (SFSV), are endemic in the Mediterranean region. In France, several autochthonous cases of TOSV infection have been described, causing either meningitis or encephalitis. The aim of the present [...] Read more.

Sandfly-borne phleboviruses pathogenic to humans, such as Toscana virus (TOSV) and Sandfly Fever Sicilian virus (SFSV), are endemic in the Mediterranean region. In France, several autochthonous cases of TOSV infection have been described, causing either meningitis or encephalitis. The aim of the present study was to investigate the seroprevalence of TOSV and SFSV antibodies in a healthy population from Corsica. In this cross-sectional study, participants were enrolled (i) from a medical staff at the University of Corsica and (ii) from general practitioners of the Corsican Sentinelles Network. The seroprevalence study was based on a virus microneutralization assay. A total of 240 sera were tested. Altogether, 54 sera (22.5%) were confirmed positive for TOSV antibodies, whereas none were positive for SFSV (0/240). The residential district of participants was significantly associated with TOSV seropositivity (p value = 0.005). The rate of the seropositivity against TOSV in our study suggests that the Corsican population is well exposed to the TOSV. These results encourage the implementation of a systematic surveillance system including entomological, microbiological, and medical aspects for the collection of better information on the diseases that are associated with phleboviruses in Corsica and beyond in the regions where these viruses are present. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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10 pages, 1676 KiB

Open AccessArticle

Investigation about the Occurrence of Transmission Cycles of Arbovirus in the Tropical Forest, Amazon Region

by Pedro A. Araújo, Maria O. Freitas, Jannifer Oliveira Chiang, Franko Arruda Silva, Liliane Leal Chagas, Samir Mansour Casseb, Sandro Patroca Silva, Joaquim Pinto Nunes-Neto, José Wilson Rosa-Júnior, Bruna Sena Nascimento, Leonardo Almeida Hernández, Thito Bezerra Paz, Landeson L. Barros, Eliana P. Silva, Raimunda S. Azevedo, Lívia C. Martins, Milene S. Ferreira and Pedro F. Vasconcelos

Viruses 2019, 11(9), 774; https://doi.org/10.3390/v11090774 - 22 Aug 2019

Cited by 16 | Viewed by 3519

Abstract

Because of its ecological characteristics, the Caxiuanã National Forest (FLONA) is a potential area of arbovirus circulation. The present study aimed to investigate the occurrence of arbovirus transmission cycles at FLONA de Caxiuanã. Five field trips were performed to capture mosquitoes and sylvatic [...] Read more.

Because of its ecological characteristics, the Caxiuanã National Forest (FLONA) is a potential area of arbovirus circulation. The present study aimed to investigate the occurrence of arbovirus transmission cycles at FLONA de Caxiuanã. Five field trips were performed to capture mosquitoes and sylvatic vertebrates. For these vertebrates, we attempted viral isolation by cell monolayer inoculation from blood, and hemagglutination inhibition and further seroneutralization assays from sera. For mosquitoes, we performed tests of viral genome detection. A total of 338 vertebrates were captured, and the greatest representative was birds (251/74.26%). A total of 16,725 mosquitoes were captured, distributed among 56 species. There were no viruses isolated by newborn mouse inoculation. Among birds, antibodies against Ilheus virus were the most prevalent. Catu virus, Caraparu virus, and Mucambo virus were the most prevalent among mammals and reptiles. Fragments of Mucambo virus, Ilheus virus, Bussuquara virus, and Rocio virus genome were detected in a pool of mosquito samples. These results of the study suggest the occurrence of arbovirus transmission cycles in the FLONA of Caxiuanã. The proximity of human populations with elements, involved in transmission cycles, makes surveillance necessary in this population to avoid dispersion of arboviruses to naïve locations. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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7 pages, 3575 KiB

Open AccessArticle

Experimental Assessment of Zika Virus Mechanical Transmission by Aedes aegypti

by Antoine Boullis, Nadège Cordel, Cécile Herrmann-Storck and Anubis Vega-Rúa

Viruses 2019, 11(8), 695; https://doi.org/10.3390/v11080695 - 31 Jul 2019

Cited by 8 | Viewed by 3786

Abstract

The pandemic emergence of several mosquito-borne viruses highlights the need to understand the different ways in which they can be transmitted by vectors to human hosts. In this study, we evaluated the propensity of Aedes aegypti to transmit mechanically Zika virus (ZIKV) using [...] Read more.

The pandemic emergence of several mosquito-borne viruses highlights the need to understand the different ways in which they can be transmitted by vectors to human hosts. In this study, we evaluated the propensity of Aedes aegypti to transmit mechanically Zika virus (ZIKV) using an experimental design. Mosquitoes were allowed to feed on ZIKV-infected blood and were then rapidly transferred to feed on ZIKV-free blood until they finished their meal. The uninfected blood meals, the mosquito abdomens, as well as the mouthparts dissected from fully and partially engorged mosquitoes were analyzed using RT-qPCR and/or virus titration. All the fully engorged mosquito abdomens were ZIKV-infected, whereas their mouthparts were all ZIKV-negative. Nonetheless, one of the partially engorged mosquitoes carried infectious particles on mouthparts. No infectious virus was found in the receiver blood meals, while viral RNA was detected in 9% of the samples (2/22). Thus, mechanical transmission of ZIKV may sporadically occur via Ae. aegypti bite. However, as the number of virions detected on mouthparts (2 particles) is not sufficient to induce infection in a naïve host, our results indicate that mechanical transmission does not impact ZIKV epidemiology. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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10 pages, 3561 KiB

Open AccessArticle

Transport via Macropinocytic Vesicles Is Crucial for Productive Infection with Bombyx Mori Nucleopolyhedrovirus

by Jinshan Huang, Chenya Li, Xudong Tang, Lin Liu, Wenbin Nan, Xingjia Shen and Bifang Hao

Viruses 2019, 11(7), 668; https://doi.org/10.3390/v11070668 - 20 Jul 2019

Cited by 9 | Viewed by 3907

Abstract

Bombyx mori nucleopolyhedrovirus (BmNPV) is a serious viral pathogen in the sericulture industry and enters host cells via macropinocytic endocytosis; however, the current understanding of the BmNPV entry mechanism remains limited. To confirm whether direct membrane fusion (DMF) results in productive BmNPV infection, [...] Read more.

Bombyx mori nucleopolyhedrovirus (BmNPV) is a serious viral pathogen in the sericulture industry and enters host cells via macropinocytic endocytosis; however, the current understanding of the BmNPV entry mechanism remains limited. To confirm whether direct membrane fusion (DMF) results in productive BmNPV infection, DMF infectivity induced by low pH during BmNPV infection was investigated, and the infectious viral particle was traced using an eGFP-labeled virion. We found that BmNPV infection efficiently induced fluid uptake, which allowed BmNPV to bypass the cell membrane barrier via macropinocytosis. However, DMF induced by a low pH abolished the infection. While low pH is an essential condition for membrane fusion triggering, it is not sufficient for productive BmNPV infection, and DMF results in failure to transport the nucleocapsid into the nucleus. These results indicate that transport via macropinocytic vesicles facilitates BmNPV entry into the nucleus and contribute to our understanding of the BmNPV entry mechanism. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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16 pages, 6613 KiB

Open AccessArticle

Assessing the Potential Interactions between Cellular miRNA and Arboviral Genomic RNA in the Yellow Fever Mosquito, Aedes aegypti

by Pei-Shi Yen, Chun-Hong Chen, Vattipally Sreenu, Alain Kohl and Anna-Bella Failloux

Viruses 2019, 11(6), 540; https://doi.org/10.3390/v11060540 - 10 Jun 2019

Cited by 14 | Viewed by 5908

Abstract

Although the role of exogenous small interfering RNA (siRNA) and P-element induced wimpy testis (PIWI)-interacting RNA (piRNA) pathways in mosquito antiviral immunity is increasingly better understood, there is still little knowledge regarding the role of mosquito cellular microRNA (miRNA). Identifying direct interactions between [...] Read more.

Although the role of exogenous small interfering RNA (siRNA) and P-element induced wimpy testis (PIWI)-interacting RNA (piRNA) pathways in mosquito antiviral immunity is increasingly better understood, there is still little knowledge regarding the role of mosquito cellular microRNA (miRNA). Identifying direct interactions between the mosquito miRNAs and the RNA genome of arboviruses and choosing the relevant miRNA candidates to explore resulting antiviral mechanisms are critical. Here, we carried out genomic analyses to identify Aedes aegypti miRNAs that potentially interact with various lineages and genotypes of chikungunya, dengue, and Zika viruses. By using prediction tools with distinct algorithms, several miRNA binding sites were commonly found within different genotypes/and or lineages of each arbovirus. We further analyzed those miRNAs that could target more than one arbovirus, required a low energy threshold to form miRNA-viralRNA (vRNA) complexes, and predicted potential RNA structures using RNAhybrid software. We predicted miRNA candidates that might participate in regulating arboviral replication in Ae. aegypti. Even without any experimental validation, which should be done as a next step, this study can shed further light on the role of miRNA in mosquito innate immunity and targets for future studies. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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18 pages, 3776 KiB

Open AccessArticle

Mosquito Small RNA Responses to West Nile and Insect-Specific Virus Infections in Aedes and Culex Mosquito Cells

by Giel P. Göertz, Pascal Miesen, Gijs J. Overheul, Ronald P. van Rij, Monique M. van Oers and Gorben P. Pijlman

Viruses 2019, 11(3), 271; https://doi.org/10.3390/v11030271 - 18 Mar 2019

Cited by 55 | Viewed by 7244

Abstract

Small RNA mediated responses are essential for antiviral defence in mosquitoes, however, they appear to differ per virus-vector combination. To further investigate the diversity of small RNA responses against viruses in mosquitoes, we applied a small RNA deep sequencing approach on five mosquito [...] Read more.

Small RNA mediated responses are essential for antiviral defence in mosquitoes, however, they appear to differ per virus-vector combination. To further investigate the diversity of small RNA responses against viruses in mosquitoes, we applied a small RNA deep sequencing approach on five mosquito cell lines: Culex tarsalis CT cells, Aedes albopictus U4.4 and C6/36 cells, Ae. aegypti Aag2 cells (cleared from cell fusing agent virus and Culex Y virus (CYV) by repetitive dsRNA transfections) and Ae. pseudoscutellaris AP-61 cells. De novo assembly of small RNAs revealed the presence of Phasi Charoen-like virus (PCLV), Calbertado virus, Flock House virus and a novel narnavirus in CT cells, CYV in U4.4 cells, and PCLV in Aag2 cells, whereas no insect-specific viruses (ISVs) were detected in C6/36 and AP-61 cells. Next, we investigated the small RNA responses to the identified ISVs and to acute infection with the arthropod-borne West Nile virus (WNV). We demonstrate that AP-61 and C6/36 cells do not produce siRNAs to WNV infection, suggesting that AP-61, like C6/36, are Dicer-2 deficient. CT cells produced a strong siRNA response to the persistent ISVs and acute WNV infection. Interestingly, CT cells also produced viral PIWI-interacting (pi)RNAs to PCLV, but not to WNV or any of the other ISVs. In contrast, in U4.4 and Aag2 cells, WNV siRNAs, and pi-like RNAs without typical ping-pong piRNA signature were observed, while this signature was present in PCLV piRNAs in Aag2 cells. Together, our results demonstrate that mosquito small RNA responses are strongly dependent on both the mosquito cell type and/or the mosquito species and family of the infecting virus. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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8 pages, 1267 KiB

Open AccessArticle

Detection of RNA-Dependent RNA Polymerase of Hubei Reo-Like Virus 7 by Next-Generation Sequencing in Aedes aegypti and Culex quinquefasciatus Mosquitoes from Brazil

by Geovani de Oliveira Ribeiro, Fred Julio Costa Monteiro, Marlisson Octavio da S Rego, Edcelha Soares D’Athaide Ribeiro, Daniela Funayama de Castro, Marcos Montani Caseiro, Robson dos Santos Souza Marinho, Shirley Vasconcelos Komninakis, Steven S. Witkin, Xutao Deng, Eric Delwart, Ester Cerdeira Sabino, Antonio Charlys da Costa and Élcio Leal

Viruses 2019, 11(2), 147; https://doi.org/10.3390/v11020147 - 10 Feb 2019

Cited by 9 | Viewed by 3330

Abstract

Advancements in next-generation sequencing and bioinformatics have expanded our knowledge of the diversity of viruses (pathogens and non-pathogens) harbored by mosquitoes. Hubei reo-like virus 7 (HRLV 7) was recently detected by the virome analysis of fecal samples from migratory birds in Australia. We [...] Read more.

Advancements in next-generation sequencing and bioinformatics have expanded our knowledge of the diversity of viruses (pathogens and non-pathogens) harbored by mosquitoes. Hubei reo-like virus 7 (HRLV 7) was recently detected by the virome analysis of fecal samples from migratory birds in Australia. We now report the detection of RNA-dependent RNA polymerase sequences of HRLV 7 in pools of Aedes aegypti and Culex quinquefasciatus mosquitoes species from the Brazilian Amazon forest. Phylogenetic inferences indicated that all HRLV 7 strains fall within the same independent clade. In addition, HRLV 7 shared a close ancestral lineage with the Dinovernavirus genus of the Reoviridae family. Our findings indicate that HRLV 7 is present in two species of mosquitoes. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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Review

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27 pages, 483 KiB

Open AccessReview

The Role of Temperature in Transmission of Zoonotic Arboviruses

by Alexander T. Ciota and Alexander C. Keyel

Viruses 2019, 11(11), 1013; https://doi.org/10.3390/v11111013 - 1 Nov 2019

Cited by 47 | Viewed by 7748

Abstract

We reviewed the literature on the role of temperature in transmission of zoonotic arboviruses. Vector competence is affected by both direct and indirect effects of temperature, and generally increases with increasing temperature, but results may vary by vector species, population, and viral strain. [...] Read more.

We reviewed the literature on the role of temperature in transmission of zoonotic arboviruses. Vector competence is affected by both direct and indirect effects of temperature, and generally increases with increasing temperature, but results may vary by vector species, population, and viral strain. Temperature additionally has a significant influence on life history traits of vectors at both immature and adult life stages, and for important behaviors such as blood-feeding and mating. Similar to vector competence, temperature effects on life history traits can vary by species and population. Vector, host, and viral distributions are all affected by temperature, and are generally expected to change with increased temperatures predicted under climate change. Arboviruses are generally expected to shift poleward and to higher elevations under climate change, yet significant variability on fine geographic scales is likely. Temperature effects are generally unimodal, with increases in abundance up to an optimum, and then decreases at high temperatures. Improved vector distribution information could facilitate future distribution modeling. A wide variety of approaches have been used to model viral distributions, although most research has focused on the West Nile virus. Direct temperature effects are frequently observed, as are indirect effects, such as through droughts, where temperature interacts with rainfall. Thermal biology approaches hold much promise for syntheses across viruses, vectors, and hosts, yet future studies must consider the specificity of interactions and the dynamic nature of evolving biological systems. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

26 pages, 4550 KiB

Open AccessReview

Mosquito-Specific Viruses—Transmission and Interaction

by Eric Agboli, Mayke Leggewie, Mine Altinli and Esther Schnettler

Viruses 2019, 11(9), 873; https://doi.org/10.3390/v11090873 - 17 Sep 2019

Cited by 69 | Viewed by 8895

Abstract

Mosquito-specific viruses (MSVs) are a subset of insect-specific viruses that are found to infect mosquitoes or mosquito derived cells. There has been an increase in discoveries of novel MSVs in recent years. This has expanded our understanding of viral diversity and evolution but [...] Read more.

Mosquito-specific viruses (MSVs) are a subset of insect-specific viruses that are found to infect mosquitoes or mosquito derived cells. There has been an increase in discoveries of novel MSVs in recent years. This has expanded our understanding of viral diversity and evolution but has also sparked questions concerning the transmission of these viruses and interactions with their hosts and its microbiome. In fact, there is already evidence that MSVs interact with the immune system of their host. This is especially interesting, since mosquitoes can be infected with both MSVs and arthropod-borne (arbo) viruses of public health concern. In this review, we give an update on the different MSVs discovered so far and describe current data on their transmission and interaction with the mosquito immune system as well as the effect MSVs could have on an arboviruses-co-infection. Lastly, we discuss potential uses of these viruses, including vector and transmission control. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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24 pages, 937 KiB

Open AccessReview

Vector Competence: What Has Zika Virus Taught Us?

by Sasha R. Azar and Scott C. Weaver

Viruses 2019, 11(9), 867; https://doi.org/10.3390/v11090867 - 17 Sep 2019

Cited by 46 | Viewed by 8962

Abstract

The unprecedented outbreak of Zika virus (ZIKV) infection in the Americas from 2015 to 2017 prompted the publication of a large body of vector competence data in a relatively short period of time. Although differences in vector competence as a result of disparities [...] Read more.

The unprecedented outbreak of Zika virus (ZIKV) infection in the Americas from 2015 to 2017 prompted the publication of a large body of vector competence data in a relatively short period of time. Although differences in vector competence as a result of disparities in mosquito populations and viral strains are to be expected, the limited competence of many populations of the urban mosquito vector, Aedes aegypti, from the Americas (when its susceptibility is viewed relative to other circulating/reemerging mosquito-borne viruses such as dengue (DENV), yellow fever (YFV), and chikungunya viruses (CHIKV)) has proven a paradox for the field. This has been further complicated by the lack of standardization in the methodologies utilized in laboratory vector competence experiments, precluding meta-analyses of this large data set. As the calls for the standardization of such studies continue to grow in number, it is critical to examine the elements of vector competence experimental design. Herein, we review the various techniques and considerations intrinsic to vector competence studies, with respect to contemporary findings for ZIKV, as well as historical findings for other arboviruses, and discuss potential avenues of standardization going forward. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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20 pages, 674 KiB

Open AccessReview

Effects of Arbovirus Multi-Host Life Cycles on Dinucleotide and Codon Usage Patterns

by Nicole R. Sexton and Gregory D. Ebel

Viruses 2019, 11(7), 643; https://doi.org/10.3390/v11070643 - 12 Jul 2019

Cited by 22 | Viewed by 5068

Abstract

Arthropod-borne viruses (arboviruses) of vertebrates including dengue, zika, chikungunya, Rift Valley fever, and blue tongue viruses cause extensive morbidity and mortality in humans, agricultural animals, and wildlife across the globe. As obligate intercellular pathogens, arboviruses must be well adapted to the cellular and [...] Read more.

Arthropod-borne viruses (arboviruses) of vertebrates including dengue, zika, chikungunya, Rift Valley fever, and blue tongue viruses cause extensive morbidity and mortality in humans, agricultural animals, and wildlife across the globe. As obligate intercellular pathogens, arboviruses must be well adapted to the cellular and molecular environment of both their arthropod (invertebrate) and vertebrate hosts, which are vastly different due to hundreds of millions of years of separate evolution. Here we discuss the comparative pressures on arbovirus RNA genomes as a result of a dual host life cycle, focusing on pressures that do not alter amino acids. We summarize what is currently known about arboviral genetic composition, such as dinucleotide and codon usage, and how cyclical infection of vertebrate and invertebrate hosts results in different genetic profiles compared with single-host viruses. To serve as a comparison, we compile what is known about arthropod tRNA, dinucleotide, and codon usages and compare this with vertebrates. Additionally, we discuss the potential roles of genetic robustness in arboviral evolution and how it may vary from other viruses. Overall, both arthropod and vertebrate hosts influence the resulting genetic composition of arboviruses, but a great deal remains to be investigated. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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14 pages, 883 KiB

Open AccessReview

Usutu Virus: An Arbovirus on the Rise

by Ferdinand Roesch, Alvaro Fajardo, Gonzalo Moratorio and Marco Vignuzzi

Viruses 2019, 11(7), 640; https://doi.org/10.3390/v11070640 - 12 Jul 2019

Cited by 78 | Viewed by 8563

Abstract

The Usutu virus (USUV) is a flavivirus that is drawing increasing attention because of its potential for emergence. First isolated in Africa, it was introduced into Europe where it caused significant outbreaks in birds, such as in Austria in 2001. Since then, its [...] Read more.

The Usutu virus (USUV) is a flavivirus that is drawing increasing attention because of its potential for emergence. First isolated in Africa, it was introduced into Europe where it caused significant outbreaks in birds, such as in Austria in 2001. Since then, its geographical distribution has rapidly expanded, with increased circulation, especially in the last few years. Similar to West Nile virus (WNV), the USUV enzootic transmission cycle involves Culex mosquitoes as vectors, and birds as amplifying reservoir hosts, with humans and other mammals likely being dead-end hosts. A similarity in the ecology of these two viruses, which co-circulate in several European countries, highlights USUV’s potential to become an important human pathogen. While USUV has had a severe impact on the blackbird population, the number of human cases remains low, with most infections being asymptomatic. However, some rare cases of neurological disease have been described, both in healthy and immuno-compromised patients. Here, we will discuss the transmission dynamics and the current state of USUV circulation in Europe. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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32 pages, 3103 KiB

Open AccessReview

Antiviral RNAi in Insects and Mammals: Parallels and Differences

by Susan Schuster, Pascal Miesen and Ronald P. van Rij

Viruses 2019, 11(5), 448; https://doi.org/10.3390/v11050448 - 16 May 2019

Cited by 66 | Viewed by 10377

Abstract

The RNA interference (RNAi) pathway is a potent antiviral defense mechanism in plants and invertebrates, in response to which viruses evolved suppressors of RNAi. In mammals, the first line of defense is mediated by the type I interferon system (IFN); however, the degree [...] Read more.

The RNA interference (RNAi) pathway is a potent antiviral defense mechanism in plants and invertebrates, in response to which viruses evolved suppressors of RNAi. In mammals, the first line of defense is mediated by the type I interferon system (IFN); however, the degree to which RNAi contributes to antiviral defense is still not completely understood. Recent work suggests that antiviral RNAi is active in undifferentiated stem cells and that antiviral RNAi can be uncovered in differentiated cells in which the IFN system is inactive or in infections with viruses lacking putative viral suppressors of RNAi. In this review, we describe the mechanism of RNAi and its antiviral functions in insects and mammals. We draw parallels and highlight differences between (antiviral) RNAi in these classes of animals and discuss open questions for future research. Full article

(This article belongs to the Special Issue Transmission Dynamics of Insect Viruses)

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