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Harrison JJ, Hobson-Peters J, Bielefeldt-Ohmann H, Hall RA. Chimeric Vaccines Based on Novel Insect-Specific Flaviviruses. Vaccines (Basel) 2021; 9:1230. [PMID: 34835160 PMCID: PMC8623431 DOI: 10.3390/vaccines9111230] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/18/2021] [Accepted: 10/19/2021] [Indexed: 12/30/2022] Open
Abstract
Vector-borne flaviviruses are responsible for nearly half a billion human infections worldwide each year, resulting in millions of cases of debilitating and severe diseases and approximately 115,000 deaths. While approved vaccines are available for some of these viruses, the ongoing efficacy, safety and supply of these vaccines are still a significant problem. New technologies that address these issues and ideally allow for the safe and economical manufacture of vaccines in resource-poor countries where flavivirus vaccines are in most demand are urgently required. Preferably a new vaccine platform would be broadly applicable to all flavivirus diseases and provide new candidate vaccines for those diseases not yet covered, as well as the flexibility to rapidly pivot to respond to newly emerged flavivirus diseases. Here, we review studies conducted on novel chimeric vaccines derived from insect-specific flaviviruses that provide a potentially safe and simple system to produce highly effective vaccines against a broad spectrum of flavivirus diseases.
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Affiliation(s)
- Jessica J. Harrison
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia; (J.H.-P.); (H.B.-O.); (R.A.H.)
| | - Jody Hobson-Peters
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia; (J.H.-P.); (H.B.-O.); (R.A.H.)
| | - Helle Bielefeldt-Ohmann
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia; (J.H.-P.); (H.B.-O.); (R.A.H.)
- School of Veterinary Science, University of Queensland, Gatton, QLD 4343, Australia
| | - Roy A. Hall
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia; (J.H.-P.); (H.B.-O.); (R.A.H.)
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2
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Fang Y, Tambo E, Xue JB, Zhang Y, Zhou XN, Khater EIM. Detection of DENV-2 and Insect-Specific Flaviviruses in Mosquitoes Collected From Jeddah, Saudi Arabia. Front Cell Infect Microbiol 2021; 11:626368. [PMID: 33718273 PMCID: PMC7947193 DOI: 10.3389/fcimb.2021.626368] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 01/18/2021] [Indexed: 12/04/2022] Open
Abstract
Background Mosquito-borne diseases are rapidly spreading due to increasing international travel and trade. Routine mosquito surveillance and screening for mosquito-borne pathogens can be early indicators for local disease transmission and outbreaks. However, arbovirus detection in mosquito vectors has rarely been reported in Saudi Arabia. Methods A total of 769,541 Aedes and Culex mosquitoes were collected by Black Hole traps during routine mosquito surveillance in the first half of 2016. Culex. quinquefasciatus and Ae. aegypti were the most prevalent species observed. Twenty-five and 24 randomly selected pools of Ae. aegypti and Cx. quinquefasciatus, respectively, were screened for arboviruses by RT-PCR. Results Dengue 2 (DENV-2) and four strains of insect-specific flaviviruses, including one of cell-fusing agent virus (CFAV) and three of Phlebotomus-associated flavivirus (PAFV) were detected in pools of Ae. aegypti. We also detected 10 strains of Culex flavivirus (CxFV) in pools of Cx. quinquefasciatus. Phylogenetic analysis using whole genome sequences placed the DENV strain into the cosmopolitan 1 sub-DENV-2 genotype, and the CxFVs into the African/Caribbean/Latin American genotype. These analyses also showed that the DENV-2 strain detected in the present study was closely related to strains detected in China in 2014 and in Japan in 2018, which suggests frequent movement of DENV-2 strains among these countries. Furthermore, the phylogenetic analysis suggested at least five introductions of DENV-2 into Saudi Arabia from 2014 through 2018, most probably from India. Conclusions To our knowledge, this study reports the first detection of four arboviruses DENV, CFAV, PAFV, and CxFV in mosquitoes in Saudi Arabia, which shows that they are co-circulating in Jeddah. Our findings show a need for widespread mosquito-based arbovirus surveillance programs in Saudi Arabia, which will improve our understanding of the transmission dynamics of the mosquito-borne arboviruses within the country and help early predict and mitigate the risk of human infections and outbreaks.
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Affiliation(s)
- Yuan Fang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China.,Chinese Center for Tropical Diseases Research, Shanghai, China.,WHO Collaborating Centre for Tropical Diseases, Shanghai, China.,National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, China.,Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention-Shenzhen Center for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China
| | - Ernest Tambo
- Public Health Pests Laboratory, Municipality of Jeddah Governorate, Jeddah, Saudi Arabia
| | - Jing-Bo Xue
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China.,Chinese Center for Tropical Diseases Research, Shanghai, China.,WHO Collaborating Centre for Tropical Diseases, Shanghai, China.,National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, China.,Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention-Shenzhen Center for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China
| | - Yi Zhang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China.,Chinese Center for Tropical Diseases Research, Shanghai, China.,WHO Collaborating Centre for Tropical Diseases, Shanghai, China.,National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, China.,Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention-Shenzhen Center for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China.,Chinese Center for Tropical Diseases Research, Shanghai, China.,WHO Collaborating Centre for Tropical Diseases, Shanghai, China.,National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, China.,Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention-Shenzhen Center for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China
| | - Emad I M Khater
- Public Health Pests Laboratory, Municipality of Jeddah Governorate, Jeddah, Saudi Arabia.,Department of Entomology, Faculty of Science, Ain Shams University, Cairo, Egypt
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3
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Schrama M, Hunting ER, Beechler BR, Guarido MM, Govender D, Nijland W, van 't Zelfde M, Venter M, van Bodegom PM, Gorsich EE. Human practices promote presence and abundance of disease-transmitting mosquito species. Sci Rep 2020; 10:13543. [PMID: 32782318 PMCID: PMC7421943 DOI: 10.1038/s41598-020-69858-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/09/2020] [Indexed: 01/20/2023] Open
Abstract
Humans alter the environment at unprecedented rates through habitat destruction, nutrient pollution and the application of agrochemicals. This has recently been proposed to act as a potentially significant driver of pathogen-carrying mosquito species (disease vectors) that pose a health risk to humans and livestock. Here, we use a unique set of locations along a large geographical gradient to show that landscapes disturbed by a variety of anthropogenic stressors are consistently associated with vector-dominated mosquito communities for a wide range of human and livestock infections. This strongly suggests that human alterations to the environment promote the presence and abundance of disease vectors across large spatial extents. As such, it warrants further studies aimed at unravelling mechanisms underlying vector prevalence in mosquito communities, and opens up new opportunities for preventative action and predictive modelling of vector borne disease risks in relation to degradation of natural ecosystems.
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Affiliation(s)
- Maarten Schrama
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands.
| | - Ellard R Hunting
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Brianna R Beechler
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA
| | - Milehna M Guarido
- Department of Medical Virology, University of Pretoria, Pretoria, South Africa
| | - Danny Govender
- Department of Medical Virology, University of Pretoria, Pretoria, South Africa
- Scientific Services, SANPARKS, Kruger National Park, Skukuza, South Africa
| | - Wiebe Nijland
- Department of Physical Geography, University of Utrecht, Utrecht, The Netherlands
| | | | - Marietjie Venter
- Department of Medical Virology, University of Pretoria, Pretoria, South Africa
| | - Peter M van Bodegom
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands
| | - Erin E Gorsich
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands
- School of Life Sciences, University of Warwick, Coventry, UK
- The Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, University of Warwick, Coventry, UK
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4
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Ramos-Nino ME, Fitzpatrick DM, Eckstrom KM, Tighe S, Hattaway LM, Hsueh AN, Stone DM, Dragon JA, Cheetham S. Metagenomic analysis of Aedes aegypti and Culex quinquefasciatus mosquitoes from Grenada, West Indies. PLoS One 2020; 15:e0231047. [PMID: 32282857 PMCID: PMC7153883 DOI: 10.1371/journal.pone.0231047] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 03/14/2020] [Indexed: 02/06/2023] Open
Abstract
The mosquitoes Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae) and Culex quinquefasciatus Say, 1823 (Diptera: Culicidae) are two major vectors of arthropod-borne pathogens in Grenada, West Indies. As conventional vector control methods present many challenges, alternatives are urgently needed. Manipulation of mosquito microbiota is emerging as a field for the development of vector control strategies. Critical to this vector control approach is knowledge of the microbiota of these mosquitoes and finding candidate microorganisms that are common to the vectors with properties that could be used in microbiota modification studies. Results showed that bacteria genera including Asaia, Escherichia, Pantoea, Pseudomonas, and Serratia are common to both major arboviral vectors in Grenada and have previously been shown to be good candidates for transgenetic studies. Also, for the first time, the presence of Grenada mosquito rhabdovirus 1 is reported in C. quinquefasciatus.
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Affiliation(s)
- Maria E. Ramos-Nino
- Department of Microbiology, Immunology, and Pharmacology, School of Medicine, St. George’s University, Grenada, West Indies
| | - Daniel M. Fitzpatrick
- Department of Pathobiology, School of Veterinary Medicine, St. George’s University, Grenada, West Indies
| | - Korin M. Eckstrom
- University of Vermont Massively Parallel Sequencing Facility, Burlington, Vermont, United States of America
| | - Scott Tighe
- University of Vermont Massively Parallel Sequencing Facility, Burlington, Vermont, United States of America
| | - Lindsey M. Hattaway
- Department of Pathobiology, School of Veterinary Medicine, St. George’s University, Grenada, West Indies
| | - Andy N. Hsueh
- Department of Pathobiology, School of Veterinary Medicine, St. George’s University, Grenada, West Indies
| | - Diana M. Stone
- Department of Pathobiology, School of Veterinary Medicine, St. George’s University, Grenada, West Indies
| | - Julie A. Dragon
- University of Vermont Massively Parallel Sequencing Facility, Burlington, Vermont, United States of America
| | - Sonia Cheetham
- Department of Pathobiology, School of Veterinary Medicine, St. George’s University, Grenada, West Indies
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5
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Öhlund P, Lundén H, Blomström AL. Insect-specific virus evolution and potential effects on vector competence. Virus Genes 2019; 55:127-137. [PMID: 30632016 PMCID: PMC6458977 DOI: 10.1007/s11262-018-01629-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 12/21/2018] [Indexed: 01/08/2023]
Abstract
The advancement in high-throughput sequencing technology and bioinformatics tools has spurred a new age of viral discovery. Arthropods is the largest group of animals and has shown to be a major reservoir of different viruses, including a group known as insect-specific viruses (ISVs). The majority of known ISVs have been isolated from mosquitoes and shown to belong to viral families associated with animal arbovirus pathogens, such as Flaviviridae, Togaviridae and Phenuiviridae. These insect-specific viruses have a strict tropism and are unable to replicate in vertebrate cells, these properties are interesting for many reasons. One is that these viruses could potentially be utilised as biocontrol agents using a similar strategy as for Wolbachia. Mosquitoes infected with the viral agent could have inferior vectorial capacity of arboviruses resulting in a decrease of circulating arboviruses of public health importance. Moreover, insect-specific viruses are thought to be ancestral to arboviruses and could be used to study the evolution of the switch from single-host to dual-host. In this review, we discuss new discoveries and hypothesis in the field of arboviruses and insect-specific viruses.
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Affiliation(s)
- Pontus Öhlund
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 750 07, Uppsala, Sweden
| | - Hanna Lundén
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 750 07, Uppsala, Sweden
| | - Anne-Lie Blomström
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 750 07, Uppsala, Sweden.
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6
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A Novel Highly Divergent Strain of Cell Fusing Agent Virus (CFAV) in Mosquitoes from the Brazilian Amazon Region. Viruses 2018; 10:v10120666. [PMID: 30477235 PMCID: PMC6315449 DOI: 10.3390/v10120666] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 11/13/2018] [Accepted: 11/22/2018] [Indexed: 11/17/2022] Open
Abstract
Classical insect-specific flaviviruses (cISFs) have been widely detected in different countries in the last decades. Here, we characterize the near full-length genomes of two cISFs detected in mosquitoes collected in the city of Macapá, state of Amapá, Amazon region of Brazil. A total of 105 pools of female mosquitos were analyzed by next-generation sequencing (NGS). Comparative genomics and phylogenetic analysis identified three strains of cell fusing agent virus (CFAV) and two of Culex flavivirus (CxFV). All sequences were obtained from pools of Culex sp., except for one sequence of CFAV detected in a pool of Aedes aegypti. Both CxFV strains are phylogenetically related to a strain isolated in 2012 in the Southeast region of Brazil. The CFAV strains are the first of this species to be identified in Brazil and one of them is highly divergent from other strains of CFAV that have been detected worldwide. In conclusion, CFAV and CxFV, circulate in mosquitoes in Brazil. One strain of CFAV is highly divergent from others previously described, suggesting that a novel strain of CFAV is present in this region.
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7
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Gravina HD, Suzukawa AA, Zanluca C, Cardozo Segovia FM, Tschá MK, Martins da Silva A, Faoro H, da Silva Ribeiro R, Mendoza Torres LP, Rojas A, Ferrerira L, Costa Ribeiro MCVD, Delfraro A, Duarte Dos Santos CN. Identification of insect-specific flaviviruses in areas of Brazil and Paraguay experiencing endemic arbovirus transmission and the description of a novel flavivirus infecting Sabethes belisarioi. Virology 2018; 527:98-106. [PMID: 30476788 DOI: 10.1016/j.virol.2018.11.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 11/26/2022]
Abstract
Viral infection was examined with pan-flavivirus and pan-alphavirus sets of primers in mosquitoes collected in four South American regions with confirmed pathogenic arbovirus circulation. Positive pools for flavivirus infection were sequenced and screened for specific arboviruses, which were not detected. However, NS5 gene sequencing showed that most sequences corresponded to the insect-specific Culex flavivirus. One sequence retrieved from an Aedes albopictus pool grouped with the insect-specific Aedes flavivirus and two Sabethes belisarioi pools were infected by a previously unknown flavivirus, tentatively named Sabethes flavivirus (SbFV). Phylogenetic inference placed SbFV as ancestral to a clade formed by Culiseta flavivirus, Mercadeo, and Calbertado. SbFV polyprotein showed an average aminoacidic identity of 51% in comparison to these flaviviruses. In vitro studies suggest that SbFV infects insect cells, but not vertebrate cells, therefore, we propose it as a new insect-specific flavivirus. These results highlight the wide distribution of insect-specific flaviviruses concomitant with the circulation of emergent arboviruses.
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Affiliation(s)
| | - Andreia Akemi Suzukawa
- Laboratório de Virologia Molecular, Instituto Carlos Chagas/Fiocruz-PR, Curitiba, PR, Brazil
| | - Camila Zanluca
- Laboratório de Virologia Molecular, Instituto Carlos Chagas/Fiocruz-PR, Curitiba, PR, Brazil
| | - Fatima María Cardozo Segovia
- Departamento de Salud Pública, Instituto de Investigaciones en Ciencias de la Salud (IICS), Universidad Nacional de Asunción (UNA), Paraguay
| | - Marcel Kruchelski Tschá
- Laboratório de Virologia Molecular, Instituto Carlos Chagas/Fiocruz-PR, Curitiba, PR, Brazil
| | - Allan Martins da Silva
- Laboratório Central, Secretaria de Estado da Saúde (SESA), São José dos Pinhais, PR, Brazil
| | - Helisson Faoro
- Laboratório de Regulação da Expressão Gênica (LRGEN), Instituto Carlos Chagas/Fiocruz-PR, Curitiba, PR, Brazil
| | - Ricardo da Silva Ribeiro
- Laboratório de Vigilância Ambiental, Centro de Vigilância em Saúde Ambiental (CVSA), Secretaria de Estado de Saúde (SESA), Vitória, ES, Brazil
| | - Laura Patricia Mendoza Torres
- Departamento de Salud Pública, Instituto de Investigaciones en Ciencias de la Salud (IICS), Universidad Nacional de Asunción (UNA), Paraguay
| | - Alejandra Rojas
- Departamento de Salud Pública, Instituto de Investigaciones en Ciencias de la Salud (IICS), Universidad Nacional de Asunción (UNA), Paraguay
| | - Luis Ferrerira
- Servicio Nacional de Erradicación del Paludismo (SENEPA), Ministerio de Salud Pública y Bienestar Social, Asunción, Paraguay
| | | | - Adriana Delfraro
- Sección Virología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
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8
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Romo H, Kenney JL, Blitvich BJ, Brault AC. Restriction of Zika virus infection and transmission in Aedes aegypti mediated by an insect-specific flavivirus. Emerg Microbes Infect 2018; 7:181. [PMID: 30429457 PMCID: PMC6235874 DOI: 10.1038/s41426-018-0180-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 10/05/2018] [Accepted: 10/08/2018] [Indexed: 11/09/2022]
Abstract
Previous studies demonstrated an insect-specific flavivirus, Nhumirim virus (NHUV), can suppress growth of West Nile virus (WNV) and decrease transmission rates in NHUV/WNV co-inoculated Culex quinquefasciatus. To assess whether NHUV might interfere with transmission of other medically important flaviviruses, the ability of NHUV to suppress viral growth of Zika virus (ZIKV) and dengue-2 virus (DENV-2) was assessed in Aedes albopictus cells. Significant reductions in ZIKV (100,000-fold) and DENV-2 (10,000-fold) were observed in either cells concurrently inoculated with NHUV or pre-inoculated with NHUV. In contrast, only a transient 10-fold titer reduction was observed with an alphavirus, chikungunya virus. Additionally, restricted in vitro mosquito growth of ZIKV was associated with lowered levels of intracellular ZIKV RNA in NHUV co-inoculated cultures. To assess whether NHUV could modulate vector competence for ZIKV, NHUV-inoculated Aedes aegypti were orally exposed to ZIKV. NHUV-inoculated mosquitoes demonstrated significantly lower ZIKV infection rates (18%) compared to NHUV unexposed mosquitoes (51%) (p < 0.002). Similarly, lower ZIKV transmission rates were observed for NHUV/ZIKV dually intrathoracically inoculated mosquitoes (41%) compared to ZIKV only inoculated mosquitoes (78%) (p < 0.0001), suggesting that NHUV can interfere with both midgut infection and salivary gland infection of ZIKV in Ae. aegypti. These results indicate NHUV could be utilized to model superinfection exclusion mechanism(s) and to study the potential for the mosquito virome to impact transmission of medically important flaviviruses.
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Affiliation(s)
- Hannah Romo
- Division of Vector-Borne Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, 80521, USA
| | - Joan L Kenney
- Division of Vector-Borne Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, 80521, USA
| | - Bradley J Blitvich
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, 50011, USA
| | - Aaron C Brault
- Division of Vector-Borne Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, 80521, USA.
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9
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Newman CM, Krebs BL, Anderson TK, Hamer GL, Ruiz MO, Brawn JD, Brown WM, Kitron UD, Goldberg TL. Culex Flavivirus During West Nile Virus Epidemic and Interepidemic Years in Chicago, United States. Vector Borne Zoonotic Dis 2017. [PMID: 28628366 DOI: 10.1089/vbz.2017.2124] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Culex flavivirus (CxFV) is an insect-specific flavivirus infecting Culex mosquitoes, which are important vectors of West Nile virus (WNV). CxFV and WNV cocirculate in nature and coinfect Culex mosquitoes, including in a WNV "hotspot" in suburban Chicago. We previously identified a positive association between CxFV and WNV in mosquito pools collected from suburban Chicago in 2006. To further investigate this phenomenon, we compared the spatial and temporal distribution of CxFV during an interepidemic year (2011) and an epidemic year (2012) for WNV. Both viruses were more prevalent in mosquito pools in 2012 compared to 2011. During both years, the CxFV infection status of mosquito pools was associated with environmental factors such as habitat type and precipitation frequency rather than coinfection with WNV. These results support the idea that WNV and CxFV are ecologically associated, perhaps because both viruses respond to similar environmental drivers of mosquito populations.
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Affiliation(s)
- Christina M Newman
- 1 Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin-Madison , Madison, Wisconsin
| | | | - Tavis K Anderson
- 3 Virus and Prion Research Unit, National Animal Disease Center , USDA-ARS, Ames, Iowa
| | - Gabriel L Hamer
- 4 Department of Entomology, Texas A&M University , College Station, Texas
| | - Marilyn O Ruiz
- 5 Department of Pathobiology, University of Illinois , Urbana, Illinois
| | - Jeffrey D Brawn
- 6 Department of Natural Resources and Environmental Sciences, University of Illinois , Urbana, Illinois
| | - William M Brown
- 5 Department of Pathobiology, University of Illinois , Urbana, Illinois
| | - Uriel D Kitron
- 7 Department of Environmental Sciences, Emory University , Atlanta, Georgia
| | - Tony L Goldberg
- 8 Department of Pathobiological Sciences, University of Wisconsin-Madison , Madison, Wisconsin
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10
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Hoyos-López R, Suaza-Vasco J, Rúa-Uribe G, Uribe S, Gallego-Gómez JC. Molecular detection of flaviviruses and alphaviruses in mosquitoes (Diptera: Culicidae) from coastal ecosystems in the Colombian Caribbean. Mem Inst Oswaldo Cruz 2016; 111:625-634. [PMID: 27706377 PMCID: PMC5066328 DOI: 10.1590/0074-02760160096] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 07/19/2016] [Indexed: 11/21/2022] Open
Abstract
Arboviruses belonging to the genera Flavivirus and Alphavirus were detected in mosquitoes in a rural area of San Bernardo del Viento (Córdoba, Colombia). A total of 22,180 mosquitoes were collected, sorted into 2,102 pools, and tested by generic/nested reverse transcription-polymerase chain reaction. Venezuelan equine encephalitis virus, dengue virus, West Nile virus, St. Louis encephalitis virus, yellow fever virus, and Culex flavivirus were detected and identified by sequencing. The detection of arboviral pathogens in this zone represents possible circulation and indicates a human health risk, demonstrating the importance of virological surveillance activities.
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Affiliation(s)
- Richard Hoyos-López
- Universidad de Antioquia, Translational and Molecular Medicine Group,
Medellín, Antioquia, Colombia
| | - Juan Suaza-Vasco
- Universidad Nacional de Colombia, Grupo de Investigación en Sistemática
Molecular, Medellín, Antioquia, Colombia
| | - Guillermo Rúa-Uribe
- Universidad de Antioquia, Facultad de Medicina, Grupo de Entomología
Médica, Medellín, Antioquia, Colombia
| | - Sandra Uribe
- Universidad Nacional de Colombia, Grupo de Investigación en Sistemática
Molecular, Medellín, Antioquia, Colombia
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11
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Bittar C, Machado DC, Vedovello D, Ullmann LS, Rahal P, Araújo Junior JP, Nogueira ML. Genome sequencing and genetic characterization of Culex Flavirirus (CxFV) provides new information about its genotypes. Virol J 2016; 13:158. [PMID: 27658621 PMCID: PMC5034531 DOI: 10.1186/s12985-016-0614-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 09/14/2016] [Indexed: 11/12/2022] Open
Abstract
Background Culex Flavivirus (CxFV) is an insect-specific virus that is widely distributed and primarily infects mosquito species from the genus Culex. Its hosts include Culex tritaeniorhynchus, Culex quinquefasciatus, and Anopheles sinensis mosquitoes. Since its original identification, CxFV has been reported in several countries. Despite the increasing number of reports on CxFV, little is known about its genomic characteristics. It is unclear whether the phylogenetic relationships between the strains are influenced by host species and geographic location. Results We characterized the Brazilian CxFV strain and performed a comprehensive genetic and phylogenetic characterization of CxFV based on all ORF sequences described so far. Our results revealed that the Brazilian strain is in a monophyletic clade with the Mexican strain. Overall, selective pressure indicates that the ORF is undergoing purifying selection. Conclusions The phylogenetic analysis revealed a strong association between climate and CxFV ancestry. Also, based on phylogeny and the genetic distance between the main branches of the tree, we propose the classification of the available sequences into two different genotypes. We also suggest the existence of two different subtypes within Genotype 1. Electronic supplementary material The online version of this article (doi:10.1186/s12985-016-0614-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cíntia Bittar
- UNESP - São Paulo State University, Rua Cristóvão Colombo, 2265 - Jardim Nazareth, CEP 15054-000, São José do Rio Preto, SP, Brazil
| | - Daiane Cristina Machado
- FAMERP - Faculdade de Medicina de São José do Rio Preto, Av. Brigadeiro Faria Lima, 5416, Bloco U6 - Vila São Pedro, CEP: 15090-000, São José do Rio Preto, SP, Brazil
| | - Danila Vedovello
- UNESP - São Paulo State University, Rua Cristóvão Colombo, 2265 - Jardim Nazareth, CEP 15054-000, São José do Rio Preto, SP, Brazil.,FAMERP - Faculdade de Medicina de São José do Rio Preto, Av. Brigadeiro Faria Lima, 5416, Bloco U6 - Vila São Pedro, CEP: 15090-000, São José do Rio Preto, SP, Brazil
| | - Leila Sabrina Ullmann
- UNESP - São Paulo State University, R. Prof. Dr. Antônio Celso Wagner Zanin S/N Bairro: Distrito de Rubião Junior, Botucatu, SP, CEP 18618-689, Brazil
| | - Paula Rahal
- UNESP - São Paulo State University, Rua Cristóvão Colombo, 2265 - Jardim Nazareth, CEP 15054-000, São José do Rio Preto, SP, Brazil
| | - João Pessoa Araújo Junior
- UNESP - São Paulo State University, R. Prof. Dr. Antônio Celso Wagner Zanin S/N Bairro: Distrito de Rubião Junior, Botucatu, SP, CEP 18618-689, Brazil
| | - Maurício Lacerda Nogueira
- FAMERP - Faculdade de Medicina de São José do Rio Preto, Av. Brigadeiro Faria Lima, 5416, Bloco U6 - Vila São Pedro, CEP: 15090-000, São José do Rio Preto, SP, Brazil.
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12
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Frey KG, Biser T, Hamilton T, Santos CJ, Pimentel G, Mokashi VP, Bishop-Lilly KA. Bioinformatic Characterization of Mosquito Viromes within the Eastern United States and Puerto Rico: Discovery of Novel Viruses. Evol Bioinform Online 2016; 12:1-12. [PMID: 27346944 PMCID: PMC4912310 DOI: 10.4137/ebo.s38518] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/01/2016] [Accepted: 05/01/2016] [Indexed: 12/14/2022] Open
Abstract
Mosquitoes are efficient, militarily relevant vectors of infectious disease pathogens, including many RNA viruses. The vast majority of all viruses are thought to be undiscovered. Accordingly, recent studies have shown that viruses discovered in insects are very divergent from known pathogens and that many of them lack appropriate reference sequences in the public databases. Given that the majority of viruses are likely still undiscovered, environ mental sampling stands to provide much needed reference samples as well as genetic sequences for comparison. In this study, we sought to determine whether samples of mosquitoes collected from different sites (the Caribbean and locations on the US East Coast) could be differentiated using metagenomic analysis of the RNA viral fraction. We report here distinct virome profiles, even from samples collected short distances apart. In addition to profiling the previously known viruses from these samples, we detected a number of viruses that have been previously undiscovered.
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Affiliation(s)
- Kenneth G Frey
- Naval Medical Research Center - Frederick, Fort Detrick, MD, USA.; Henry M. Jackson Foundation, Bethesda, MD, USA
| | - Tara Biser
- Naval Medical Research Center - Frederick, Fort Detrick, MD, USA.; Hood College, Frederick, MD, USA
| | - Theron Hamilton
- Naval Medical Research Center - Frederick, Fort Detrick, MD, USA
| | | | | | | | - Kimberly A Bishop-Lilly
- Naval Medical Research Center - Frederick, Fort Detrick, MD, USA.; Henry M. Jackson Foundation, Bethesda, MD, USA
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13
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Fernandes LN, Paula MBD, Araújo AB, Gonçalves EFB, Romano CM, Natal D, Malafronte RDS, Marrelli MT, Levi JE. Detection of Culex flavivirus and Aedes flavivirus nucleotide sequences in mosquitoes from parks in the city of São Paulo, Brazil. Acta Trop 2016; 157:73-83. [PMID: 26829359 DOI: 10.1016/j.actatropica.2016.01.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/22/2016] [Accepted: 01/24/2016] [Indexed: 11/28/2022]
Abstract
The dengue viruses are widespread in Brazil and are a major public health concern. Other flaviviruses also cause diseases in humans, although on a smaller scale. The city of São Paulo is in a highly urbanized area with few green spaces apart from its parks, which are used for recreation and where potential vertebrate hosts and mosquito vectors of pathogenic Flavivirus species can be found. Although this scenario can contribute to the transmission of Flavivirus to humans, little is known about the circulation of members of this genus in these areas. In light of this, the present study sought to identify Flavivirus infection in mosquitoes (Diptera: Culicidae) collected in parks in the city of São Paulo. Seven parks in different sectors of the city were selected. Monthly mosquito collections were carried out in each park from March 2011 to February 2012 using aspiration and traps (Shannon and CD C-CO2). Nucleic acids were extracted from the mosquitoes collected and used for reverse-transcriptase and real-time polymerase chain reactions with genus-specific primers targeting a 200-nucleotide region in the Flavivirus NS5 gene. Positive samples were sequenced, and phylogenetic analyses were performed. Culex and Aedes were the most frequent genera of Culicidae collected. Culex flavivirus (CxFV)-related and Aedes flavivirus (AEFV)- related nucleotide sequences were detected in 17 pools of Culex and two pools of Aedes mosquitoes, respectively, among the 818 pools of non-engorged females analyzed. To the best of our knowledge, this is the first report of CxFV and AEFV in the city of São Paulo and Latin America, respectively. Both viruses are insect- specific flaviviruses, a group known to replicate only in mosquito cells and induce a cytopathic effect in some situations. Hence, our data suggests that CxFV and AEFV are present in Culex and Aedes mosquitoes, respectively, in parks in the city of São Paulo. Even though Flavivirus species of medical importance were not detected, surveillance is recommended in the study areas because of the presence of vertebrates and mosquitoes that could act as amplifying hosts and vectors of flaviviruses, providing the required conditions for circulation of these viruses.
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14
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Misencik MJ, Grubaugh ND, Andreadis TG, Ebel GD, Armstrong PM. Isolation of a Novel Insect-Specific Flavivirus from Culiseta melanura in the Northeastern United States. Vector Borne Zoonotic Dis 2016; 16:181-90. [PMID: 26807512 DOI: 10.1089/vbz.2015.1889] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The genus Flavivirus includes a number of newly recognized viruses that infect and replicate only within mosquitoes. To determine whether insect-specific flaviviruses (ISFs) may infect Culiseta (Cs.) melanura mosquitoes, we screened pools of field-collected mosquitoes for virus infection by RT-PCR targeting conserved regions of the NS5 gene. NS5 nucleotide sequences amplified from Cs. melanura pools were genetically similar to other ISFs and most closely matched Calbertado virus from Culex tarsalis, sharing 68.7% nucleotide and 76.1% amino acid sequence identity. The complete genome of one virus isolate was sequenced to reveal a primary open reading frame (ORF) encoding a viral polyprotein characteristic of the genus Flavivirus. Phylogenetic analysis showed that this virus represents a distinct evolutionary lineage that belongs to the classical ISF group. The virus was detected solely in Cs. melanura pools, occurred in sampled populations from Connecticut, New York, New Hampshire, and Maine, and infected both adult and larval stages of the mosquito. Maximum likelihood estimate infection rates (MLE-IR) were relatively stable in overwintering Cs. melanura larvae collected monthly from November of 2012 through May of 2013 (MLE-IR = 0.7-2.1/100 mosquitoes) and in host-seeking females collected weekly from June through October of 2013 (MLE-IR = 3.8-11.5/100 mosquitoes). Phylogenetic analysis of viral sequences revealed limited genetic variation that lacked obvious geographic structure among strains in the northeastern United States. This new virus is provisionally named Culiseta flavivirus on the basis of its host association with Cs. melanura.
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Affiliation(s)
- Michael J Misencik
- 1 Center for Vector Biology and Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Nathan D Grubaugh
- 2 Arthropod-Borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology, and Pathology, Colorado State University , Fort Collins, Colorado
| | - Theodore G Andreadis
- 1 Center for Vector Biology and Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Gregory D Ebel
- 2 Arthropod-Borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology, and Pathology, Colorado State University , Fort Collins, Colorado
| | - Philip M Armstrong
- 1 Center for Vector Biology and Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
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15
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Bolling BG, Weaver SC, Tesh RB, Vasilakis N. Insect-Specific Virus Discovery: Significance for the Arbovirus Community. Viruses 2015; 7:4911-28. [PMID: 26378568 PMCID: PMC4584295 DOI: 10.3390/v7092851] [Citation(s) in RCA: 181] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 07/31/2015] [Accepted: 07/31/2015] [Indexed: 01/23/2023] Open
Abstract
Arthropod-borne viruses (arboviruses), especially those transmitted by mosquitoes, are a significant cause of morbidity and mortality in humans and animals worldwide. Recent discoveries indicate that mosquitoes are naturally infected with a wide range of other viruses, many within taxa occupied by arboviruses that are considered insect-specific. Over the past ten years there has been a dramatic increase in the literature describing novel insect-specific virus detection in mosquitoes, which has provided new insights about viral diversity and evolution, including that of arboviruses. It has also raised questions about what effects the mosquito virome has on arbovirus transmission. Additionally, the discovery of these new viruses has generated interest in their potential use as biological control agents as well as novel vaccine platforms. The arbovirus community will benefit from the growing database of knowledge concerning these newly described viral endosymbionts, as their impacts will likely be far reaching.
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Affiliation(s)
- Bethany G Bolling
- Institute for Human Infections and Immunity, Center for Tropical Diseases, and Department of Pathology,University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Scott C Weaver
- Institute for Human Infections and Immunity, Center for Tropical Diseases, and Department of Pathology,University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Robert B Tesh
- Institute for Human Infections and Immunity, Center for Tropical Diseases, and Department of Pathology,University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Nikos Vasilakis
- Institute for Human Infections and Immunity, Center for Tropical Diseases, and Department of Pathology,University of Texas Medical Branch, Galveston, TX 77555, USA.
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16
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Calzolari M, Zé-Zé L, Vázquez A, Sánchez Seco MP, Amaro F, Dottori M. Insect-specific flaviviruses, a worldwide widespread group of viruses only detected in insects. INFECTION GENETICS AND EVOLUTION 2015; 40:381-388. [PMID: 26235844 DOI: 10.1016/j.meegid.2015.07.032] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 01/06/2023]
Abstract
Several flaviviruses are important pathogens for humans and animals (Dengue viruses, Japanese encephalitis virus, Yellow-fever virus, Tick-borne encephalitis virus, West Nile virus). In recent years, numerous novel and related flaviviruses without known pathogenic capacity have been isolated worldwide in the natural mosquito population. However, phylogenetic studies have shown that genomic sequences of these viruses diverge from other flaviviruses. Moreover, these viruses seem to be exclusive of insects (they do not seem to grow on vertebrate cell lines), and were already defined as mosquito-only flaviviruses or insect-specific flaviviruses. At least eleven of these viruses were isolated worldwide, and sequences ascribable to other eleven putative viruses were detected in several mosquito species. A large part of the cycle of these viruses is not well known, and their persistence in the environment is poorly understood. These viruses are detected in a wide variety of distinct mosquito species and also in sandflies and chironomids worldwide; a single virus, or the genetic material ascribable to a virus, was detected in several mosquito species in different countries, often in different continents. Furthermore, some of these viruses are carried by invasive mosquitoes, and do not seem to have a depressive action on their fitness. The global distribution and the continuous detection of new viruses in this group point out the likely underestimation of their number, and raise interesting issues about their possible interactions with the pathogenic flaviviruses, and their influence on the bionomics of arthropod hosts. Some enigmatic features, as their integration in the mosquito genome, the recognition of their genetic material in DNA forms in field-collected mosquitoes, or the detection of the same virus in both mosquitoes and sandflies, indicate that the cycle of these viruses has unknown characteristics that could be of use to reach a deeper understanding of the cycle of related pathogenic flaviviruses.
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Affiliation(s)
- Mattia Calzolari
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy.
| | - Líbia Zé-Zé
- Centre for Vectors and Infectious Diseases Research, National Institute of Health, Avenida da Liberdade 5, 2965-575 Águas de Moura, Portugal; University of Lisbon, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, Lisbon, Portugal.
| | - Ana Vázquez
- Laboratory of Arbovirus and Imported Viral Diseases, National Center of Microbiology, Institute of Health "Carlos III", Ctra Pozuelo-Majadahonda km 2, 28220 Madrid, Spain.
| | - Mari Paz Sánchez Seco
- Laboratory of Arbovirus and Imported Viral Diseases, National Center of Microbiology, Institute of Health "Carlos III", Ctra Pozuelo-Majadahonda km 2, 28220 Madrid, Spain.
| | - Fátima Amaro
- Centre for Vectors and Infectious Diseases Research, National Institute of Health, Avenida da Liberdade 5, 2965-575 Águas de Moura, Portugal.
| | - Michele Dottori
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy.
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17
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Isolation of Japanese encephalitis virus and a novel insect-specific flavivirus from mosquitoes collected in a cowshed in Japan. Arch Virol 2015; 160:2151-9. [PMID: 26085283 DOI: 10.1007/s00705-015-2488-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/07/2015] [Indexed: 10/23/2022]
Abstract
Cattle do not generally appear to develop severe viremia when infected with Japanese encephalitis virus (JEV), and they can be infected without showing clinical signs. However, two cattle in Japan recently died from JEV infection. In this study, we investigated the presence of different species of mosquitoes and flavivirus in a cowshed in the southwest region of Japan. In this cowshed, the two most common species of mosquitoes collected were Culex tritaeniorhynchus (including Culex pseudovishnui) and Anopheles sinensis. We performed virus isolation from the collected mosquitoes and obtained two flaviviruses: JEV and a novel insect-specific flavivirus, tentatively designated Yamadai flavivirus (YDFV). Phylogenetic analysis revealed that all three JEV isolates belonged to JEV genotype I and were closely related to a JEV strain that was isolated from the brains of cattle exhibiting neurological symptoms in Japan. Genetic characterization of YDFV revealed that the full genome RNA (10,863 nucleotides) showed homology with the Culex-associated insect-specific flaviviruses Quang Binh virus (79% identity) and Yunnan Culex flavivirus (78% identity), indicating that YDFV is a novel insect-specific flavivirus.
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18
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Blitvich BJ, Firth AE. Insect-specific flaviviruses: a systematic review of their discovery, host range, mode of transmission, superinfection exclusion potential and genomic organization. Viruses 2015; 7:1927-59. [PMID: 25866904 PMCID: PMC4411683 DOI: 10.3390/v7041927] [Citation(s) in RCA: 226] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 03/30/2015] [Accepted: 04/08/2015] [Indexed: 12/11/2022] Open
Abstract
There has been a dramatic increase in the number of insect-specific flaviviruses (ISFs) discovered in the last decade. Historically, these viruses have generated limited interest due to their inability to infect vertebrate cells. This viewpoint has changed in recent years because some ISFs have been shown to enhance or suppress the replication of medically important flaviviruses in co-infected mosquito cells. Additionally, comparative studies between ISFs and medically important flaviviruses can provide a unique perspective as to why some flaviviruses possess the ability to infect and cause devastating disease in humans while others do not. ISFs have been isolated exclusively from mosquitoes in nature but the detection of ISF-like sequences in sandflies and chironomids indicates that they may also infect other dipterans. ISFs can be divided into two distinct phylogenetic groups. The first group currently consists of approximately 12 viruses and includes cell fusing agent virus, Kamiti River virus and Culex flavivirus. These viruses are phylogenetically distinct from all other known flaviviruses. The second group, which is apparently not monophyletic, currently consists of nine viruses and includes Chaoyang virus, Nounané virus and Lammi virus. These viruses phylogenetically affiliate with mosquito/vertebrate flaviviruses despite their apparent insect-restricted phenotype. This article provides a review of the discovery, host range, mode of transmission, superinfection exclusion ability and genomic organization of ISFs. This article also attempts to clarify the ISF nomenclature because some of these viruses have been assigned more than one name due to their simultaneous discoveries by independent research groups.
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Affiliation(s)
- Bradley J Blitvich
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
| | - Andrew E Firth
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK.
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19
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Liang G, Gao X, Gould EA. Factors responsible for the emergence of arboviruses; strategies, challenges and limitations for their control. Emerg Microbes Infect 2015; 4:e18. [PMID: 26038768 PMCID: PMC4395659 DOI: 10.1038/emi.2015.18] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 02/13/2015] [Accepted: 02/16/2015] [Indexed: 12/25/2022]
Abstract
Slave trading of Africans to the Americas, during the 16th to the 19th century was responsible for the first recorded emergence in the New World of two arthropod-borne viruses (arboviruses), yellow fever virus and dengue virus. Many other arboviruses have since emerged from their sylvatic reservoirs and dispersed globally due to evolving factors that include anthropological behaviour, commercial transportation and land-remediation. Here, we outline some characteristics of these highly divergent arboviruses, including the variety of life cycles they have developed and the mechanisms by which they have adapted to evolving changes in habitat and host availability. We cite recent examples of virus emergence that exemplify how arboviruses have exploited the consequences of the modern human lifestyle. Using our current understanding of these viruses, we also attempt to demonstrate some of the limitations encountered in developing control strategies to reduce the impact of future emerging arbovirus diseases. Finally, we present recommendations for development by an international panel of experts reporting directly to World Health Organization, with the intention of providing internationally acceptable guidelines for improving emerging arbovirus disease control strategies. Success in these aims should alleviate the suffering and costs encountered during recent decades when arboviruses have emerged from their sylvatic environment.
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Affiliation(s)
- Guodong Liang
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Centre for Disease Control and Prevention , Beijing 102206, China ; Collaborative Innovation Centre for Diagnosis and Treatment of Infectious Diseases , Hangzhou 310003, Zhejiang province, China
| | - Xiaoyan Gao
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Centre for Disease Control and Prevention , Beijing 102206, China ; Collaborative Innovation Centre for Diagnosis and Treatment of Infectious Diseases , Hangzhou 310003, Zhejiang province, China
| | - Ernest A Gould
- Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 "Emergence des Pathologies Virales" , Marseille 13385, France ; Centre for Ecology & Hydrology , Oxford OX1 3SR, United Kingdom
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20
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Moureau G, Cook S, Lemey P, Nougairede A, Forrester NL, Khasnatinov M, Charrel RN, Firth AE, Gould EA, de Lamballerie X. New insights into flavivirus evolution, taxonomy and biogeographic history, extended by analysis of canonical and alternative coding sequences. PLoS One 2015; 10:e0117849. [PMID: 25719412 PMCID: PMC4342338 DOI: 10.1371/journal.pone.0117849] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 01/02/2015] [Indexed: 12/20/2022] Open
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.
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Affiliation(s)
- Gregory Moureau
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Shelley Cook
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom
| | - Philippe Lemey
- Department of Microbiology and Immunology, Rega Institute, KU Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Antoine Nougairede
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Naomi L. Forrester
- Institute for Human Infections and Immunity and Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, United States of America
| | - Maxim Khasnatinov
- Centre for Ecology and Hydrology, Maclean Building, Benson Lane, Crowmarsh, Gifford, Wallingford, Oxfordshire, OX10, United Kingdom
| | - Remi N. Charrel
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Andrew E. Firth
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom
| | - Ernest A. Gould
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Xavier de Lamballerie
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
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21
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Pauvolid-Corrêa A, Solberg O, Couto-Lima D, Kenney J, Serra-Freire N, Brault A, Nogueira R, Langevin S, Komar N. Nhumirim virus, a novel flavivirus isolated from mosquitoes from the Pantanal, Brazil. Arch Virol 2015; 160:21-7. [PMID: 25252815 PMCID: PMC4785999 DOI: 10.1007/s00705-014-2219-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 08/01/2014] [Indexed: 11/25/2022]
Abstract
We describe the isolation of a novel flavivirus, isolated from a pool of mosquitoes identified as Culex (Culex) chidesteri collected in 2010 in the Pantanal region of west-central Brazil. The virus is herein designated Nhumirim virus (NHUV) after the name of the ranch from which the mosquito pool was collected. Flavivirus RNA was detected by real-time RT-PCR of homogenized mosquitoes and from the corresponding C6/36 culture supernatant. Based on full-genome sequencing, the virus isolate was genetically distinct from but most closely related to Barkedji virus (BJV), a newly described flavivirus from Senegal. Phylogenetic analysis demonstrated that NHUV grouped with mosquito-borne flaviviruses forming a clade with BJV. This clade may be genetically intermediate between the Culex-borne flaviviruses amplified by birds and the insect-only flaviviruses.
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Affiliation(s)
- Alex Pauvolid-Corrêa
- Laboratório de Flavivírus, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Ministério da Saúde, Rio de Janeiro, RJ, Brazil,
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22
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Kenney JL, Solberg OD, Langevin SA, Brault AC. Characterization of a novel insect-specific flavivirus from Brazil: potential for inhibition of infection of arthropod cells with medically important flaviviruses. J Gen Virol 2014; 95:2796-2808. [PMID: 25146007 DOI: 10.1099/vir.0.068031-0] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the past decade, there has been an upsurge in the number of newly described insect-specific flaviviruses isolated pan-globally. We recently described the isolation of a novel flavivirus (tentatively designated 'Nhumirim virus'; NHUV) that represents an example of a unique subset of apparently insect-specific viruses that phylogenetically affiliate with dual-host mosquito-borne flaviviruses despite appearing to be limited to replication in mosquito cells. We characterized the in vitro growth potential and 3' untranslated region (UTR) sequence homology with alternative flaviviruses, and evaluated the virus's capacity to suppress replication of representative Culex spp.-vectored pathogenic flaviviruses in mosquito cells. Only mosquito cell lines were found to support NHUV replication, further reinforcing the insect-specific phenotype of this virus. Analysis of the sequence and predicted RNA secondary structures of the 3' UTR indicated NHUV to be most similar to viruses within the yellow fever serogroup and Japanese encephalitis serogroup, and viruses in the tick-borne flavivirus clade. NHUV was found to share the fewest conserved sequence elements when compared with traditional insect-specific flaviviruses. This suggests that, despite apparently being insect specific, this virus probably diverged from an ancestral mosquito-borne flavivirus. Co-infection experiments indicated that prior or concurrent infection of mosquito cells with NHUV resulted in a significant reduction in virus production of West Nile virus (WNV), St Louis encephalitis virus (SLEV) and Japanese encephalitis virus. The inhibitory effect was most effective against WNV and SLEV with over a 10(6)-fold and 10(4)-fold reduction in peak titres, respectively.
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Affiliation(s)
- Joan L Kenney
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80521, USA
| | | | | | - Aaron C Brault
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80521, USA
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23
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Huhtamo E, Cook S, Moureau G, Uzcátegui NY, Sironen T, Kuivanen S, Putkuri N, Kurkela S, Harbach RE, Firth AE, Vapalahti O, Gould EA, de Lamballerie X. Novel flaviviruses from mosquitoes: mosquito-specific evolutionary lineages within the phylogenetic group of mosquito-borne flaviviruses. Virology 2014; 464-465:320-329. [PMID: 25108382 PMCID: PMC4170750 DOI: 10.1016/j.virol.2014.07.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 03/07/2014] [Accepted: 07/01/2014] [Indexed: 01/17/2023]
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. Mosquito-borne flavivirus-related viruses were isolated from Finnish mosquitoes. Isolates were reactive with flavivirus antibodies but appeared mosquito-specific. Sequence analysis identified related viruses from different parts of the world. These viruses represent unique properties among the mosquito-borne flavivirus group.
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Affiliation(s)
- Eili Huhtamo
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Shelley Cook
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom
| | - Gregory Moureau
- UMR D 190 "Emergence des Pathologies Virales", Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, 27 Boulevard Jean Moulin, Marseille 13005, France
| | - Nathalie Y Uzcátegui
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Tarja Sironen
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Suvi Kuivanen
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Niina Putkuri
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Satu Kurkela
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Virology and Immunology, Helsinki University Central Hospital Laboratory (HUSLAB), P.O. Box 400, Haartmaninkatu 3, 00029 HUS, Helsinki, Finland
| | - Ralph E Harbach
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom
| | - Andrew E Firth
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom
| | - Olli Vapalahti
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Virology and Immunology, Helsinki University Central Hospital Laboratory (HUSLAB), P.O. Box 400, Haartmaninkatu 3, 00029 HUS, Helsinki, Finland; Division of Microbiology and Epidemiology, Department of Basic Veterinary Sciences, University of Helsinki, Helsinki, Finland
| | - Ernest A Gould
- UMR D 190 "Emergence des Pathologies Virales", Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, 27 Boulevard Jean Moulin, Marseille 13005, France
| | - Xavier de Lamballerie
- UMR D 190 "Emergence des Pathologies Virales", Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, 27 Boulevard Jean Moulin, Marseille 13005, France
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Goenaga S, Fabbri CM, García JB, Rondán JC, Gardenal N, Calderón GE, Enria DA, Levis SMC. New strains of Culex flavivirus isolated in Argentina. JOURNAL OF MEDICAL ENTOMOLOGY 2014; 51:900-906. [PMID: 25118428 DOI: 10.1603/me13172] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Strains of Culex flavivirus (CxFV), an insect virus isolated initially from Japan, were isolated from different species of Culex sp. mosquitoes collected in Corrientes province, Argentina, during 2009. CxFV was detected by reverse transcription polymerase chain reaction and by isolation in C6/36 cell culture. Phylogenetic analysis of nucleotide sequences showed that these strains are related closely to a CxFV strain isolated from Trinidad. Our study represents the first report of CxFV isolation and characterization in Argentina from the same geographic area where West Nile Virus has been detected. Further evaluation and viral competition studies will be necessary to determine the impact of this insect flavivirus on an infection caused by other pathogenic flaviviruses.
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25
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Cook S, Chung BYW, Bass D, Moureau G, Tang S, McAlister E, Culverwell CL, Glücksman E, Wang H, Brown TDK, Gould EA, Harbach RE, de Lamballerie X, Firth AE. Novel virus discovery and genome reconstruction from field RNA samples reveals highly divergent viruses in dipteran hosts. PLoS One 2013; 8:e80720. [PMID: 24260463 PMCID: PMC3832450 DOI: 10.1371/journal.pone.0080720] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 10/07/2013] [Indexed: 12/17/2022] Open
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.
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Affiliation(s)
- Shelley Cook
- Department of Life Sciences, Natural History Museum, London, United Kingdom
- * E-mail: (SC); (AEF)
| | - Betty Y.-W. Chung
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - David Bass
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Gregory Moureau
- UMR_D 190 "Emergence des Pathologies Virales" (Aix-Marseille Univ. IRD French Institute of Research for Development EHESP French School of Public Health), Marseille, France
| | - Shuoya Tang
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Erica McAlister
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | | | - Edvard Glücksman
- Department of General Botany, University Duisburg-Essen, Essen, Germany
| | - Hui Wang
- Centre for Ecology & Hydrology, Wallingford, Oxfordshire, United Kingdom
| | - T. David K. Brown
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Ernest A. Gould
- UMR_D 190 "Emergence des Pathologies Virales" (Aix-Marseille Univ. IRD French Institute of Research for Development EHESP French School of Public Health), Marseille, France
- Centre for Ecology & Hydrology, Wallingford, Oxfordshire, United Kingdom
| | - Ralph E. Harbach
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Xavier de Lamballerie
- UMR_D 190 "Emergence des Pathologies Virales" (Aix-Marseille Univ. IRD French Institute of Research for Development EHESP French School of Public Health), Marseille, France
| | - Andrew E. Firth
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (SC); (AEF)
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Ferreira DD, Cook S, Lopes Â, de Matos AP, Esteves A, Abecasis A, de Almeida APG, Piedade J, Parreira R. Characterization of an insect-specific flavivirus (OCFVPT) co-isolated from Ochlerotatus caspius collected in southern Portugal along with a putative new Negev-like virus. Virus Genes 2013; 47:532-45. [PMID: 23877720 DOI: 10.1007/s11262-013-0960-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 07/10/2013] [Indexed: 10/26/2022]
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.
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Affiliation(s)
- Daniela Duque Ferreira
- Unidade de Microbiologia Médica, Grupo de Virologia, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Rua da Junqueira 100, 1349-008, Lisbon, Portugal
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Chen YY, Lin JW, Fan YC, Tu WC, Chang GJJ, Chiou SS. First detection of the Africa/Caribbean/Latin American subtype of Culex flavivirus in Asian country, Taiwan. Comp Immunol Microbiol Infect Dis 2013; 36:387-96. [PMID: 23466196 DOI: 10.1016/j.cimid.2013.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 02/01/2013] [Accepted: 02/04/2013] [Indexed: 11/26/2022]
Abstract
Culex flavivirus (CxFV), a member of the genus flavivirus, is a novel insect-specific flaviviruses that can be divided into two subtypes, the cytopathic Asia/U.S. and the noncytopathic Africa/Caribbean/Latin American subtypes. The CxFV circulates in several Asian countries, and here we conducted the first study investigating CxFV in Taiwan. A total of 14,016 mosquitoes were collected between 2010 and 2012 and 3.4% (6/179) of the pools were CxFV-positive. The phylogenetic analyses indicate that the Taiwan isolates are closely related to the Africa/Caribbean/Latin American subtype, but form an independent cluster. In the cytology experiments, the CxFV Taiwan isolate infected only mosquito cells and caused cell-cell fusion that might be associated with a unique glycine residue at position 117 within the envelope protein, which is shared with the cytopathic effect-causing Asia/US subtype. This study marks the first time the Africa/Caribbean/Latin American subtype of CxFV has been identified in an Asian country and grouped into a novel cluster.
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Affiliation(s)
- Yi-Ying Chen
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
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28
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Morales-Betoulle ME, Komar N, Panella NA, Alvarez D, López MR, Betoulle JL, Sosa SM, Müller ML, Kilpatrick AM, Lanciotti RS, Johnson BW, Powers AM, Cordón-Rosales C. West Nile virus ecology in a tropical ecosystem in Guatemala. Am J Trop Med Hyg 2012; 88:116-26. [PMID: 23149586 DOI: 10.4269/ajtmh.2012.12-0276] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
West Nile virus ecology has yet to be rigorously investigated in the Caribbean Basin. We identified a transmission focus in Puerto Barrios, Guatemala, and established systematic monitoring of avian abundance and infection, seroconversions in domestic poultry, and viral infections in mosquitoes. West Nile virus transmission was detected annually between May and October from 2005 to 2008. High temperature and low rainfall enhanced the probability of chicken seroconversions, which occurred in both urban and rural sites. West Nile virus was isolated from Culex quinquefasciatus and to a lesser extent, from Culex mollis/Culex inflictus, but not from the most abundant Culex mosquito, Culex nigripalpus. A calculation that combined avian abundance, seroprevalence, and vertebrate reservoir competence suggested that great-tailed grackle (Quiscalus mexicanus) is the major amplifying host in this ecosystem. West Nile virus transmission reached moderate levels in sentinel chickens during 2007, but less than that observed during outbreaks of human disease attributed to West Nile virus in the United States.
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29
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Roiz D, Vázquez A, Rosso F, Arnoldi D, Girardi M, Cuevas L, Perez-Pastrana E, Sánchez-Seco MP, Tenorio A, Rizzoli A. Detection of a new insect flavivirus and isolation of Aedes flavivirus in Northern Italy. Parasit Vectors 2012; 5:223. [PMID: 23043958 PMCID: PMC3481474 DOI: 10.1186/1756-3305-5-223] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 09/28/2012] [Indexed: 11/16/2022] Open
Abstract
Background During recent years, numerous novel ‘insect flaviviruses’ have been discovered in natural mosquito populations. In a previous study we described the presence of flavivirus DNA sequences integrated in Aedes albopictus (Asian tiger mosquito) populations from Northern Italy in 2007. Methods During 2008 we collected and tested Aedes females for flavivirus presence and developed phylogenetic analysis, virus isolation, electron microscopy studies and RNAse treatments. Results We detected a high prevalence of flavivirus in Ae. albopictus (77.5%). The phylogenetic analysis identified the insect flavivirus sequences as Aedes flavivirus (AEFV) recently described in Japan, and that may have been introduced in Italy travelling with the tiger mosquito. Some of these pools grew in C6/36 cells, producing cytopathic effects, and the RNase treatment results showed the presence of the detected sequences in RNA forms. Furthermore, we detected a new insect flavivirus in one pool of Aedes cinereus/geminus mosquitoes. Phylogenetic analysis of this virus shows that it forms a distinct cluster within the clade of insect flavivirus. Conclusions This is the first study to report a high prevalence, to describe the seasonal activity and an isolation of the insect flavivirus Aedes flavivirus in Europe. Moreover we describe the detection of a new insect flavivirus detected from Ae. cinereus mosquitoes from Italy. These flavivirus may be common, ubiquitous and diverse in nature and we discuss the implications of the insect flavivirus group in virus evolution and transmission.
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Affiliation(s)
- David Roiz
- Wetland Ecology Department, Doñana Biological Station, CSIC, Sevilla, Spain.
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30
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Huhtamo E, Moureau G, Cook S, Julkunen O, Putkuri N, Kurkela S, Uzcátegui NY, Harbach RE, Gould EA, Vapalahti O, de Lamballerie X. Novel insect-specific flavivirus isolated from northern Europe. Virology 2012; 433:471-8. [PMID: 22999256 PMCID: PMC3919202 DOI: 10.1016/j.virol.2012.08.038] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 06/18/2012] [Accepted: 08/20/2012] [Indexed: 11/29/2022]
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.
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Affiliation(s)
- Eili Huhtamo
- Infection Biology Research Program, Research Programs Unit, Department of Virology, Haartman Institute, University of Helsinki, Helsinki FIN-00014, Finland.
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Machado DC, Mondini A, Santana VDS, Yonamine PTK, Chiaravalloti Neto F, Zanotto PMDA, Nogueira ML. First Identification of Culex flavivirus (Flaviviridae) in Brazil. Intervirology 2012; 55:475-83. [DOI: 10.1159/000337166] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 01/31/2012] [Indexed: 11/19/2022] Open
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32
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Isawa H, Kuwata R, Tajima S, Hoshino K, Sasaki T, Takasaki T, Kobayashi M, Sawabe K. Construction of an infectious cDNA clone of Culex flavivirus, an insect-specific flavivirus from Culex mosquitoes. Arch Virol 2012; 157:975-9. [PMID: 22297417 DOI: 10.1007/s00705-012-1240-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 12/21/2011] [Indexed: 11/30/2022]
Abstract
Culex flavivirus (CxFV) is an insect-specific flavivirus that has recently been detected in various Culex spp. mosquitoes worldwide. Here, we report the successful construction of a full-length infectious cDNA clone of a Tokyo strain, CxFV-NIID21. The full-length CxFV-NIID21 cDNA was cloned into the low-copy-number plasmid pMW119, which was stably amplified in Escherichia coli. Transfection of a mosquito cell line with in vitro-transcribed RNA from the cDNA clone resulted in the production of recombinant progeny virus with growth properties, cytopathogenicity, and virion morphology similar to the parental virus.
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Affiliation(s)
- Haruhiko Isawa
- Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
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Calzolari M, Zé-Zé L, Růžek D, Vázquez A, Jeffries C, Defilippo F, Osório HC, Kilian P, Ruíz S, Fooks AR, Maioli G, Amaro F, Tlustý M, Figuerola J, Medlock JM, Bonilauri P, Alves MJ, Šebesta O, Tenorio A, Vaux AGC, Bellini R, Gelbič I, Sánchez-Seco MP, Johnson N, Dottori M. Detection of mosquito-only flaviviruses in Europe. J Gen Virol 2012; 93:1215-1225. [DOI: 10.1099/vir.0.040485-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The genus Flavivirus, family Flaviviridae, includes a number of important arthropod-transmitted human pathogens such as dengue viruses, West Nile virus, Japanese encephalitis virus and yellow fever virus. In addition, the genus includes flaviviruses without a known vertebrate reservoir, which have been detected only in insects, particularly in mosquitoes, such as cell fusing agent virus, Kamiti River virus, Culex flavivirus, Aedes flavivirus, Quang Binh virus, Nakiwogo virus and Calbertado virus. Reports of the detection of these viruses with no recognized pathogenic role in humans are increasing in mosquitoes collected around the world, particularly in those sampled in entomological surveys targeting pathogenic flaviviruses. The presence of six potential flaviviruses, detected from independent European arbovirus surveys undertaken in the Czech Republic, Italy,Portugal, Spain and the UK between 2007 and 2010, is reported in this work. Whilst the Aedes flaviviruses, detected in Italy from Aedes albopictus mosquitoes, had already been isolated in Japan, the remaining five viruses have not been reported previously: one was detected in Italy, Portugal and Spain from Aedes mosquitoes (particularly from Aedes caspius), one in Portugal and Spain from Culex theileri mosquitoes, one in the Czech Republic and Italy from Aedes vexans, one in the Czech Republic from Aedes vexans and the last in the UK from Aedes cinereus. Phylogenetic analysis confirmed the close relationship of these putative viruses to other insect-only flaviviruses.
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Affiliation(s)
- Mattia Calzolari
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna ‘B. Ubertini’ (IZSLER), via Bianchi 9, 25124, Brescia, Italy
| | - Líbia Zé-Zé
- Centro de Estudos de Vectores e Doenças Infecciosas (CEVDI), Instituto Nacional de Saúde Dr. Ricardo Jorge, Avenida da Liberdade 5, 2965-575 Águas de Moura, Portugal
| | - Daniel Růžek
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, Branišovská 31, CZ-37005 České Budějovice, Czech Republic
| | - Ana Vázquez
- Laboratory of Arboviruses and Imported Viral Diseases, National Center for Microbiology, Instituto de Salud Carlos III (ISCIII), Majadahonda, 28220, Madrid, Spain
| | - Claire Jeffries
- Wildlife Zoonoses and Vector-borne Diseases Research Group, Animal Health and Veterinary Laboratories Agency (AHVLA), Woodham Lane, Surrey, KT15 3NB, UK
| | - Francesco Defilippo
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna ‘B. Ubertini’ (IZSLER), via Bianchi 9, 25124, Brescia, Italy
| | - Hugo Costa Osório
- Centro de Estudos de Vectores e Doenças Infecciosas (CEVDI), Instituto Nacional de Saúde Dr. Ricardo Jorge, Avenida da Liberdade 5, 2965-575 Águas de Moura, Portugal
| | - Patrik Kilian
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic and Faculty of Science, University of South Bohemia, Branišovská 31, CZ-37005 České Budějovice, Czech Republic
| | - Santiago Ruíz
- Mosquito Control Service of Diputación Provincial de Huelva, Andalucía, Spain
| | - Anthony R. Fooks
- Animal Health and Veterinary Laboratories Agency (AHVLA), Woodham Lane, Surrey, KT15 3NB and the National Centre for Zoonosis Research, University of Liverpool, Leahurst Chester High Road, CH64 7TE Neston, UK
| | - Giulia Maioli
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna ‘B. Ubertini’ (IZSLER), via Bianchi 9, 25124, Brescia, Italy
| | - Fátima Amaro
- Centro de Estudos de Vectores e Doenças Infecciosas (CEVDI), Instituto Nacional de Saúde Dr. Ricardo Jorge, Avenida da Liberdade 5, 2965-575 Águas de Moura, Portugal
| | - Martin Tlustý
- Pierre de Coubertin High School in Tábor, František Křižík Sq. 860, CZ-39030 Tábor, Czech Republic
| | - Jordi Figuerola
- Estación Biológica de Doñana - CSIC. Avda. Américo Vespucio s/n, 41092-Sevilla, Spain
| | - Jolyon M. Medlock
- Medical Entomology and Zoonoses Ecology Group, Microbial Risk Assessment, Emergency Response Department, Health Protection Agency (HPA), Porton Down, Wiltshire, SP4 0JG, UK
| | - Paolo Bonilauri
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna ‘B. Ubertini’ (IZSLER), via Bianchi 9, 25124, Brescia, Italy
| | - Maria João Alves
- Centro de Estudos de Vectores e Doenças Infecciosas (CEVDI), Instituto Nacional de Saúde Dr. Ricardo Jorge, Avenida da Liberdade 5, 2965-575 Águas de Moura, Portugal
| | - Oldřich Šebesta
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, CZ-603 65 Brno, Czech Republic
| | - Antonio Tenorio
- Laboratory of Arboviruses and Imported Viral Diseases, National Center for Microbiology, Instituto de Salud Carlos III (ISCIII), Majadahonda, 28220, Madrid, Spain
| | - Alexander G. C. Vaux
- Medical Entomology and Zoonoses Ecology Group, Microbial Risk Assessment, Emergency Response Department, Health Protection Agency (HPA), Porton Down, Wiltshire, SP4 0JG, UK
| | - Romeo Bellini
- Centro Agricoltura Ambiente ‘G. Nicoli’, Via Argini Nord 3351, 40014 Crevalcore, Italy
| | - Ivan Gelbič
- Institute of Entomology, Biology Centre of the Academy of Sciences of the Czech Republic, Branišovská 31, CZ-37005 České Budějovice, Czech Republic
| | - Maria Paz Sánchez-Seco
- Laboratory of Arboviruses and Imported Viral Diseases, National Center for Microbiology, Instituto de Salud Carlos III (ISCIII), Majadahonda, 28220, Madrid, Spain
| | - Nicholas Johnson
- Animal Health and Veterinary Laboratories Agency (AHVLA), Woodham Lane, Surrey, KT15 3NB and the National Centre for Zoonosis Research, University of Liverpool, Leahurst Chester High Road, CH64 7TE Neston, UK
| | - Michele Dottori
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna ‘B. Ubertini’ (IZSLER), via Bianchi 9, 25124, Brescia, Italy
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Parreira R, Cook S, Lopes Â, de Matos AP, de Almeida APG, Piedade J, Esteves A. Genetic characterization of an insect-specific flavivirus isolated from Culex theileri mosquitoes collected in southern Portugal. Virus Res 2012; 167:152-61. [PMID: 22579596 PMCID: PMC3919203 DOI: 10.1016/j.virusres.2012.04.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 03/30/2012] [Accepted: 04/11/2012] [Indexed: 12/04/2022]
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.
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Affiliation(s)
- Ricardo Parreira
- Unidade de Microbiologia Médica, Grupo de Virologia, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira 100, 1349-008 Lisboa, Portugal.
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Huanyu W, Haiyan W, Shihong F, Guifang L, Hong L, Xiaoyan G, Lizhi S, Rayner S, Aiqiang X, Guodong L. Isolation and identification of a distinct strain of Culex Flavivirus from mosquitoes collected in Mainland China. Virol J 2012; 9:73. [PMID: 22452813 PMCID: PMC3349510 DOI: 10.1186/1743-422x-9-73] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 03/27/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Culexflavivirus (CxFV) is an insect specific virus that has been isolated from Culexpipiens, Culexquinquefasciatus, Culextritaeniorhynchus and other Culex mosquitoes. It is a novel flavivirus isolated in Asia, North America, Central America and Africa. Phylogenetic analysis indicates that, based on the envelope gene (E gene) sequence, the worldwide CxFV strains can be divided into two genotypes. RESULT A virus (SDDM06-11) was isolated from Culexpipiens collected in Shandong Province, China in 2006. The strain caused cytopathic effect (CPE) in Aedesalbopictus (C6/36) cells by 3 days post-infection and immunofluorescence assay (IFA) showed a reaction with Japanese encephalitis virus (JEV) polyclonal antibodies. Phylogenetic analysis of the E gene sequence showed CxFV formed two genotypes with the SDDM06-11 strain assigned to genotype 1. Analysis of the E gene nucleotide homology showed the virus possessed characteristic amino acids at specific sites. The nucleotide homology of the open reading frame (ORF) was 94.8%-95.1% between SDDM06-11 and isolates from Japan, Iowa and Texas, and 90.2%-90.5% between SDDM06-11 and isolates from Uganda and Mexico. CONCLUSION In this paper we report the first isolation and identification of an isolate of CxFV in mainland China. Phylogenetic analysis indicates the isolate belongs to genotype 1. Our findings provide insight into the occurrence of CxFV in Culex mosquito populations and its distribution on a global scale.
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Affiliation(s)
- Wang Huanyu
- State Key Laboratory for Infectious Disease Prevention and Control, Department of Viral Encephalitis, Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 102206, People’s Republic of China
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Bolling BG, Olea-Popelka FJ, Eisen L, Moore CG, Blair CD. Transmission dynamics of an insect-specific flavivirus in a naturally infected Culex pipiens laboratory colony and effects of co-infection on vector competence for West Nile virus. Virology 2012; 427:90-7. [PMID: 22425062 DOI: 10.1016/j.virol.2012.02.016] [Citation(s) in RCA: 179] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 01/26/2012] [Accepted: 02/22/2012] [Indexed: 12/01/2022]
Abstract
We established a laboratory colony of Culex pipiens mosquitoes from eggs collected in Colorado and discovered that mosquitoes in the colony are naturally infected with Culex flavivirus (CxFV), an insect-specific flavivirus. In this study we examined transmission dynamics of CxFV and effects of persistent CxFV infection on vector competence for West Nile virus (WNV). We found that vertical transmission is the primary mechanism for persistence of CxFV in Cx. pipiens, with venereal transmission potentially playing a minor role. Vector competence experiments indicated possible early suppression of WNV replication by persistent CxFV infection in Cx. pipiens. This is the first description of insect-specific flavivirus transmission dynamics in a naturally infected mosquito colony and the observation of delayed dissemination of superinfecting WNV suggests that the presence of CxFV may impact the intensity of enzootic transmission of WNV and the risk of human exposure to this important pathogen.
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Affiliation(s)
- Bethany G Bolling
- Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA.
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Crockett RK, Burkhalter K, Mead D, Kelly R, Brown J, Varnado W, Roy A, Horiuchi K, Biggerstaff BJ, Miller B, Nasci R. Culex flavivirus and West Nile virus in Culex quinquefasciatus populations in the southeastern United States. JOURNAL OF MEDICAL ENTOMOLOGY 2012; 49:165-174. [PMID: 22308785 DOI: 10.1603/me11080] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Little is known of the interactions between insect-only flaviviruses and other arboviruses in their mosquito hosts, or the potential public health significance of these associations. The specific aims of this study were to describe the geographic distribution, prevalence, and seasonal infection rates of Culex flavivirus (CxFV) and West Nile virus (WNV) in Culex quinquefasciatus Say in the Southeastern United States, investigate the potential association between CxFV and WNV prevalence in Cx. quinquefasciatus and describe the phylogenetic relationship among CxFV and WNV isolates from the Southeastern United States and around the world. Using ArboNET records, 11 locations were selected across Georgia, Mississippi, and Louisiana that represented a range of WNV human case incidence levels. Cx. quinquefasciatus were trapped weekly throughout the summer of 2009 and pools were screened for flavivirus RNA by reverse transcriptase polymerase chain reaction. Cx. quinquefasciatus from Georgia had significantly higher CxFV infection rates than either Mississippi or Louisiana. CxFV was not detected in Mississippi after July, and no CxFV was detected in Cx. quinquefasciatus in Louisiana. In Georgia, CxFV infection rates were variable between and within counties and over time. WNV infection rates were not significantly different across states or months, and WNV sequences from all three states were identical to each other in the envelope and NS5 gene regions. Phylogenetically, NS5 and E gene sequences from Georgia CxFV isolates clustered with CxFV from Japan, Iowa, and Texas. Multiple CxFV genetic variants were found circulating simultaneously in Georgia. No evidence was found supporting an association between WNV and CxFV infection prevalence in Cx. quinquefasciatus.
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Affiliation(s)
- Rebekah Kent Crockett
- Centers for Disease Control and Prevention, Division of Vector-borne Diseases, Arbovirus Diseases Branch, Fort Collins, CO 80521, USA.
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Hoshino K, Takahashi-Nakaguchi A, Isawa H, Sasaki T, Higa Y, Kasai S, Tsuda Y, Sawabe K, Kobayashi M. Entomological surveillance for flaviviruses at migratory bird stopover sites in Hokkaido, Japan, and a new insect flavivirus detected in Aedes galloisi (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2012; 49:175-182. [PMID: 22308786 DOI: 10.1603/me11123] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
To investigate the possible spread of West Nile virus (WNV) into Japan, we carried out entomological surveillance for flaviviruses at migratory bird stopover sites in Hokkaido, Japan, during 2003-2006. A total of 3,826 mosquitoes, identified as 15 species in five genera, were collected and 2,465 of these were grouped into 123 pools that were assayed for cytopathic effects on mosquito and mammalian cell cultures and for flavivirus RNA by reverse transcription-polymerase chain reaction using flavivirus universal primer sets for fragments of the NS3 and NS5 genes. Neither WNV nor other mosquito-vertebrate transmitted flaviviruses were detected in mosquitoes collected at any of the sites in Hokkaido, but five Culex flaviviruses and one novel Aedes galloisi flavivirus were identified from Culex pipiens L. s. l. and Aedes galloisi Yamada, respectively. Genetic and phylogenetic analyses based on the partial NS5 nucleotide sequences classified Aedes galloisi flavivirus with the insect flavivirus, but distant from Cell fusing agent, Kamiti river virus, and Culex flaviviruses, showing <74% sequence identities. Polymerase chain reaction-based bloodmeal analysis of 79 females showed that all of the Aedes and Ochlerotatus mosquitoes fed on mammals (deer and humans), whereas, Cx. pipiens s. l. mosquitoes fed on both of avian (ducks and sparrows, 85.7%) and mammalian hosts (dog, 14.3%). We suggest that to date WNV has not become established in Japan.
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Affiliation(s)
- Keita Hoshino
- Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
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Vázquez A, Sánchez-Seco MP, Palacios G, Molero F, Reyes N, Ruiz S, Aranda C, Marqués E, Escosa R, Moreno J, Figuerola J, Tenorio A. Novel flaviviruses detected in different species of mosquitoes in Spain. Vector Borne Zoonotic Dis 2011; 12:223-9. [PMID: 22022811 DOI: 10.1089/vbz.2011.0687] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We report the characterization of three novel flaviviruses isolated in Spain. Marisma Mosquito virus, a novel mosquito borne virus, was isolated from Ochlerotatus caspius mosquitoes; Spanish Ochlerotatus flavivirus and Spanish Culex flavivirus, two novel insect flaviviruses, were isolated from Oc. caspius and Culex pipiens, respectively. During this investigation, we designed a sensitive RT-nested polymerase chain reaction method that amplifies a 1019bp fragment of the flavivirus NS5 gene and could be directly used in clinical or environmental samples for flavivirus characterization and surveillance. Analysis of the sequence generated from that amplicon contains enough phylogenetic information for proper taxonomic studies. Moreover, the use of this tool allowed the detection of additional flavivirus DNA forms in Culex, Culiseta, and Ochlerotatus mosquitoes.
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Affiliation(s)
- Ana Vázquez
- Laboratory of Arboviruses and Imported Viral Diseases, National Center for Microbiology, Instituto de Salud Carlos III-ISCIII, Madrid, Spain.
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Cook S, Moureau G, Kitchen A, Gould EA, de Lamballerie X, Holmes EC, Harbach RE. Molecular evolution of the insect-specific flaviviruses. J Gen Virol 2011; 93:223-234. [PMID: 22012464 PMCID: PMC3352342 DOI: 10.1099/vir.0.036525-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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.
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Affiliation(s)
- Shelley Cook
- Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Gregory Moureau
- Unité des Virus Emergents UMR190, Université de la Méditerranée, Institut de Recherche pour le Développement, EHESP French School of Public Health, Marseille, France
| | - Andrew Kitchen
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Ernest A Gould
- Centre for Ecology and Hydrology, Wallingford, Oxfordshire OX10 8BB, UK.,Unité des Virus Emergents UMR190, Université de la Méditerranée, Institut de Recherche pour le Développement, EHESP French School of Public Health, Marseille, France
| | - Xavier de Lamballerie
- Unité des Virus Emergents UMR190, Université de la Méditerranée, Institut de Recherche pour le Développement, EHESP French School of Public Health, Marseille, France
| | - Edward C Holmes
- Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA.,Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
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Bolling BG, Eisen L, Moore CG, Blair CD. Insect-specific flaviviruses from Culex mosquitoes in Colorado, with evidence of vertical transmission. Am J Trop Med Hyg 2011; 85:169-77. [PMID: 21734144 DOI: 10.4269/ajtmh.2011.10-0474] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Mosquitoes were collected in Colorado during 2006 and 2007 to examine spatial and seasonal patterns of risk for exposure to Culex vectors and West Nile virus. We used universal flavivirus primers to test pools of Culex mosquitoes for viral RNA. This led to the detection and subsequent isolation of two insect-specific flaviviruses: Culex flavivirus (CxFV), which was first described from Japan, and a novel insect flavivirus, designated Calbertado virus (CLBOV), which has also been detected in California and Canada. We recorded both viruses in Cx. tarsalis and Cx. pipiens from Colorado. Furthermore, quantitative reverse transcription polymerase chain reaction (RT-PCR) revealed the presence of CxFV RNA in Cx. pipiens eggs and larvae from a laboratory colony established in 2005 and naturally infected with CxFV, suggesting vertical transmission as a means of viral maintenance in natural Culex populations. Finally, we present phylogenetic analyses of the relationships between insect-specific flaviviruses and other selected flaviviruses.
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Affiliation(s)
- Bethany G Bolling
- Arthropod-Borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80521, USA.
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Tyler S, Bolling BG, Blair CD, Brault AC, Pabbaraju K, Armijos MV, Clark DC, Calisher CH, Drebot MA. Distribution and phylogenetic comparisons of a novel mosquito flavivirus sequence present in Culex tarsalis Mosquitoes from western Canada with viruses isolated in California and Colorado. Am J Trop Med Hyg 2011; 85:162-8. [PMID: 21734143 DOI: 10.4269/ajtmh.2011.10-0469] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In a previous study, a new flavivirus genome sequence was identified in Culex tarsalis mosquitoes obtained in Alberta, Canada and was shown to be genetically related to but distinct from members of the insect-specific flaviviruses. Nonstructural protein 5-encoding sequences amplified from Cx. tarsalis pools from western Canada have shown a high similarity to genome sequences of novel flaviviruses isolated from mosquitoes in California and Colorado. Despite wide distribution of this virus, designated Calbertado virus, strains demonstrate a high degree of nonstructural protein 5 nucleotide (> 90%) and amino acid (> 97%) identity. The ecology and geographic range of Calbertado virus warrants further study because it may potentially influence transmission of mosquito-borne flaviviruses, including important human pathogens such as West Nile and Saint Louis encephalitis viruses.
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Affiliation(s)
- Shaun Tyler
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.
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43
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Saiyasombat R, Bolling BG, Brault AC, Bartholomay LC, Blitvich BJ. Evidence of efficient transovarial transmission of Culex flavivirus by Culex pipiens (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2011; 48:1031-1038. [PMID: 21936322 DOI: 10.1603/me11043] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This study determined the transovarial transmission (TOT) potential and tissue tropisms of Culex flavivirus (CxFV), an insect-specific flavivirus, in Culex pipiens (L.). Several hundred mosquito egg rafts were collected in the field, transferred to the insectaries, reared to the fourth larval instar, and identified using morphological characteristics. Cx. pipiens were reared to adults, allowed to oviposit in individual containers, and tested for CxFV RNA by reverse transcription-polymerase chain reaction (RT-PCR) and nucleotide sequencing. Eighteen CxFV RNA-positive females were identified from 26 females that oviposited viable egg rafts. Thirty F1 adults from each positive female were individually tested by RT-PCR for CxFV RNA. Viral RNA was detected in 526 of 540 progeny, and thus, the filial infection rate was 97.4%. Because all 18 positive females produced infected offspring, the TOT prevalence was 100%. These data indicated that efficient TOT of CxFV occurs in nature. To define the tissue tropisms of CxFV, different tissues (salivary glands, ovaries, testes, head, fat bodies, and midguts) were removed from the remainder of the F1 and tested by RT-PCR for CxFV RNA. Viral RNA was detected in all tissues. Additionally, uninfected laboratory-colonized Cx. pipiens were infected with CxFV by needle inoculation, and ovaries were collected at 4, 6, 8, and 12 d postinoculation and tested for CxFV RNA by RT-PCR. Viral RNA was detected at all time points, demonstrating that CxFV infects the ovaries as early as 4 d postinoculation. Surprisingly, however, we were unable to demonstrate transovarial transmission despite the presence of viral RNA in the ovaries. Nevertheless, the experiments performed with field-infected Cx. pipiens demonstrate that TOT is an efficient mechanism by which CxFV is maintained in mosquitoes in nature.
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Affiliation(s)
- Rungrat Saiyasombat
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
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Newman CM, Cerutti F, Anderson TK, Hamer GL, Walker ED, Kitron UD, Ruiz MO, Brawn JD, Goldberg TL. Culex flavivirus and West Nile virus mosquito coinfection and positive ecological association in Chicago, United States. Vector Borne Zoonotic Dis 2011; 11:1099-105. [PMID: 21254845 DOI: 10.1089/vbz.2010.0144] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Culex flavivirus (CxFV) is an insect-specific flavivirus globally distributed in mosquitoes of the genus Culex. CxFV was positively associated with West Nile virus (WNV) infection in a case-control study of 268 mosquito pools from an endemic focus of WNV transmission in Chicago, United States. Specifically, WNV-positive Culex mosquito pools were four times more likely also to be infected with CxFV than were spatiotemporally matched WNV-negative pools. In addition, mosquito pools from residential sites characterized by dense housing and impermeable surfaces were more likely to be infected with CxFV than were pools from nearby urban green spaces. Further, 6/15 (40%) WNV-positive individual mosquitoes were also CxFV positive, demonstrating that both viruses can coinfect mosquitoes in nature. Phylogenetic analysis of CxFV from Chicago demonstrated a pattern similar to WNV, consisting of low global viral diversity and lack of geographic clustering. These results illustrate a positive ecological association between CxFV and WNV, and that coinfection of individual mosquitoes can occur naturally in areas of high flaviviral transmission. These conclusions represent a challenge to the hypothesis of super-infection exclusion in the CxFV/WNV system, whereby an established infection with one virus may interfere with secondary viral infection with a similar virus. This study suggests that infection with insect-specific flaviviruses such as CxFV may not exclude secondary infection with genetically distinct flaviviruses such as WNV, and that both viruses can naturally coinfect mosquitoes that are epidemic bridge vectors of WNV to humans.
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Affiliation(s)
- Christina M Newman
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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45
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Farfan-Ale JA, Loroño-Pino MA, Garcia-Rejon JE, Soto V, Lin M, Staley M, Dorman KS, Bartholomay LC, Hovav E, Blitvich BJ. Detection of flaviviruses and orthobunyaviruses in mosquitoes in the Yucatan Peninsula of Mexico in 2008. Vector Borne Zoonotic Dis 2010; 10:777-83. [PMID: 20370430 PMCID: PMC2976644 DOI: 10.1089/vbz.2009.0196] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
A total of 191,244 mosquitoes from 24 species were collected in the Yucatan Peninsula of Mexico from January to December 2008, and tested for the presence of cytopathic virus by virus isolation in Vero cells. Eighteen virus isolates were obtained, all of which were orthobunyaviruses. These were identified by reverse transcription-polymerase chain reaction (RT-PCR) and nucleotide sequencing as Cache Valley virus (n=17) and South River virus (n=1). A subset (n=20,124) of Culex quinquefasciatus collected throughout the year was further tested by RT-PCR using flavivirus-specific primers. Flavivirus RNA was present in this mosquito species year-round. The overall flavivirus minimal infection rate, expressed as the number of positive mosquito pools per 1000 mosquitoes tested, was 7.7 and the monthly flavivirus minimal infection rates ranged from 4.3 to 16.6. Approximately one-third of the RT-PCR products were sequenced and all corresponded to Culex flavivirus, a recently discovered insect-specific flavivirus.
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Affiliation(s)
- Jose A. Farfan-Ale
- Laboratorio de Arbovirologia, Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autonoma de Yucatan, Merida, Mexico
| | - Maria A. Loroño-Pino
- Laboratorio de Arbovirologia, Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autonoma de Yucatan, Merida, Mexico
| | - Julian E. Garcia-Rejon
- Laboratorio de Arbovirologia, Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autonoma de Yucatan, Merida, Mexico
| | - Victor Soto
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Ming Lin
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Molly Staley
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Karin S. Dorman
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
| | - Lyric C. Bartholomay
- Department of Entomology, College of Agriculture and Life Sciences, Iowa State University, Ames, Iowa
| | - Einat Hovav
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Bradley J. Blitvich
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa
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Bollati M, Alvarez K, Assenberg R, Baronti C, Canard B, Cook S, Coutard B, Decroly E, de Lamballerie X, Gould EA, Grard G, Grimes JM, Hilgenfeld R, Jansson AM, Malet H, Mancini EJ, Mastrangelo E, Mattevi A, Milani M, Moureau G, Neyts J, Owens RJ, Ren J, Selisko B, Speroni S, Steuber H, Stuart DI, Unge T, Bolognesi M. Structure and functionality in flavivirus NS-proteins: perspectives for drug design. Antiviral Res 2010; 87:125-48. [PMID: 19945487 PMCID: PMC3918146 DOI: 10.1016/j.antiviral.2009.11.009] [Citation(s) in RCA: 241] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/08/2009] [Accepted: 11/21/2009] [Indexed: 12/28/2022]
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.
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Affiliation(s)
- Michela Bollati
- Department of Biomolecular Sciences and Biotechnology, University of Milano, Via Celoria 26, 20133 Milano, Italy
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Moureau G, Ninove L, Izri A, Cook S, De Lamballerie X, Charrel RN. Flavivirus RNA in phlebotomine sandflies. Vector Borne Zoonotic Dis 2010; 10:195-7. [PMID: 19492949 DOI: 10.1089/vbz.2008.0216] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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.
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Affiliation(s)
- Gregory Moureau
- Unité des Virus Emergents, UMR 190 Emergence des Pathologies Virales, Université de la Méditerranée & Institut de Recherche pour le Développement, Marseille, France
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Detection of West Nile viral RNA from field-collected mosquitoes in tropical regions by conventional and real-time RT-PCR. Methods Mol Biol 2010. [PMID: 20300994 DOI: 10.1007/978-1-60761-629-0_8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
West Nile virus (WNV) is an emerging mosquito-borne flavivirus, which has rapidly spread and is currently widely distributed. Therefore, efforts for WNV early detection and ecological surveillance of this disease agent have been increased around the world. Although virus isolation is known to be the standard method for detection and identification of viruses, the use of RT-PCR assays as routine laboratory tests provides a rapid alterative suitable for the detection of viral RNA on field-collected samples. A method for WNV RNA genome detection in field-collected mosquitoes is presented in this chapter. This method has been designed for virus surveillance in tropical regions endemic for other flaviviruses. Reverse Transcriptase-PCR (RT-PCR) assays, both standard and real time, to detect WNV and other flaviviruses are described. A first screening for flavivirus RNA detection is performed using a conventional RT-PCR with two different sets of flavivirus consensus primers. Mosquito samples are then tested for WNV RNA by a real-time (TaqMan) RT-PCR assay. Sample preparation and RNA extraction procedures are also described.
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Kent RJ, Crabtree MB, Miller BR. Transmission of West Nile virus by Culex quinquefasciatus say infected with Culex Flavivirus Izabal. PLoS Negl Trop Dis 2010; 4:e671. [PMID: 20454569 PMCID: PMC2864301 DOI: 10.1371/journal.pntd.0000671] [Citation(s) in RCA: 134] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Accepted: 03/18/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The natural history and potential impact of mosquito-specific flaviviruses on the transmission efficiency of West Nile virus (WNV) is unknown. The objective of this study was to determine whether or not prior infection with Culex flavivirus (CxFV) Izabal altered the vector competence of Cx. quinquefasciatus Say for transmission of a co-circulating strain of West Nile virus (WNV) from Guatemala. METHODS AND FINDINGS CxFV-negative Culex quinquefasciatus and those infected with CxFV Izabal by intrathoracic inoculation were administered WNV-infectious blood meals. Infection, dissemination, and transmission of WNV were measured by plaque titration on Vero cells of individual mosquito bodies, legs, or saliva, respectively, two weeks following WNV exposure. Additional groups of Cx. quinquefasciatus were intrathoracically inoculated with WNV alone or WNV+CxFV Izabal simultaneously, and saliva collected nine days post inoculation. Growth of WNV in Aedes albopictus C6/36 cells or Cx. quinquefasciatus was not inhibited by prior infection with CxFV Izabal. There was no significant difference in the vector competence of Cx. quinquefasciatus for WNV between mosquitoes uninfected or infected with CxFV Izabal across multiple WNV blood meal titers and two colonies of Cx. quinquefasciatus (p>0.05). However, significantly more Cx. quinquefasciatus from Honduras that were co-inoculated simultaneously with both viruses transmitted WNV than those inoculated with WNV alone (p = 0.0014). Co-inoculated mosquitoes that transmitted WNV also contained CxFV in their saliva, whereas mosquitoes inoculated with CxFV alone did not contain virus in their saliva. CONCLUSIONS In the sequential infection experiments, prior infection with CxFV Izabal had no significant impact on WNV replication, infection, dissemination, or transmission by Cx. quinquefasciatus, however WNV transmission was enhanced in the Honduras colony when mosquitoes were inoculated simultaneously with both viruses.
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Affiliation(s)
- Rebekah J Kent
- Division of Vector-Borne Infectious Diseases, Arbovirus Diseases Branch, Centers for Disease Control and Prevention, Fort Collins, Colorado, USA.
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Isolation and sequence analysis of Culex flavivirus from Culex interrogator and Culex quinquefasciatus in the Yucatan Peninsula of Mexico. Arch Virol 2010; 155:983-6. [PMID: 20379749 DOI: 10.1007/s00705-010-0665-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Accepted: 03/13/2010] [Indexed: 10/19/2022]
Abstract
Previously, we reported a high prevalence of Culex flavivirus (CxFV) in Culex quinquefasciatus (Say) in the Yucatan Peninsula of Mexico. To determine whether other Culex spp. mosquitoes in this region are susceptible to natural CxFV infection, Cx. bahamensis (Dyar and Knab), Cx. coronator (Dyar and Knab), Cx. interrogator (Dyar and Knab), Cx. nigripalpus (Theobald) and Cx. opisthopus (Komp) in the Yucatan Peninsula of Mexico were tested for CxFV. Two pools of Cx. interrogator were positive. The envelope protein genes of these isolates and 16 isolates from Cx. quinquefasciatus were sequenced and shown to have > or =99.2% nucleotide identity. These data suggest that there is limited genetic diversity among CxFV isolates in the Yucatan Peninsula of Mexico.
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