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Korhonen EM, Truong Nguyen PT, Faolotto G, Suvanto MT, Nicosia AM, Crobu MG, Grasso I, Vapalahti O, Smura T, Ravanini P, Huhtamo E. Complete coding sequence of an Aedes flavivirus strain isolated from Aedes albopictus collected in Northern Italy. Microbiol Resour Announc 2024:e0014624. [PMID: 38917449 DOI: 10.1128/mra.00146-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 06/07/2024] [Indexed: 06/27/2024] Open
Abstract
Complete genome data for the globally distributed Aedes flavivirus (AEFV) is scarce. We analyzed a new Italian AEFV strain isolated from Aedes albopictus. The results demonstrated genetic diversity among Italian AEFVs. The high similarity between AEFV genomes across geographically distant regions suggests long distance spreading via invasive host mosquito species.
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Affiliation(s)
- Essi M Korhonen
- Department of Virology, Medicum, University of Helsinki, Helsinki, Finland
| | | | - Giulia Faolotto
- Laboratory of Microbiology and Virology, University Hospital Maggiore Della Carità Di Novara, Italy, Piemonte, Novara
| | - Maija T Suvanto
- Department of Virology, Medicum, University of Helsinki, Helsinki, Finland
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Anna Maria Nicosia
- Laboratory of Microbiology and Virology, University Hospital Maggiore Della Carità Di Novara, Italy, Piemonte, Novara
| | - Maria Grazia Crobu
- Laboratory of Microbiology and Virology, University Hospital Maggiore Della Carità Di Novara, Italy, Piemonte, Novara
| | - Ivan Grasso
- Laboratory of Microbiology and Virology, University Hospital Maggiore Della Carità Di Novara, Italy, Piemonte, Novara
| | - Olli Vapalahti
- Department of Virology, Medicum, University of Helsinki, Helsinki, Finland
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Department of Virology and Immunology, Helsinki University Hospital Diagnostic Center, Helsinki, Finland
| | - Teemu Smura
- Department of Virology, Medicum, University of Helsinki, Helsinki, Finland
| | - Paolo Ravanini
- Laboratory of Microbiology and Virology, University Hospital Maggiore Della Carità Di Novara, Italy, Piemonte, Novara
| | - Eili Huhtamo
- Department of Virology, Medicum, University of Helsinki, Helsinki, Finland
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
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Hollingsworth BD, Grubaugh ND, Lazzaro BP, Murdock CC. Leveraging insect-specific viruses to elucidate mosquito population structure and dynamics. PLoS Pathog 2023; 19:e1011588. [PMID: 37651317 PMCID: PMC10470969 DOI: 10.1371/journal.ppat.1011588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023] Open
Abstract
Several aspects of mosquito ecology that are important for vectored disease transmission and control have been difficult to measure at epidemiologically important scales in the field. In particular, the ability to describe mosquito population structure and movement rates has been hindered by difficulty in quantifying fine-scale genetic variation among populations. The mosquito virome represents a possible avenue for quantifying population structure and movement rates across multiple spatial scales. Mosquito viromes contain a diversity of viruses, including several insect-specific viruses (ISVs) and "core" viruses that have high prevalence across populations. To date, virome studies have focused on viral discovery and have only recently begun examining viral ecology. While nonpathogenic ISVs may be of little public health relevance themselves, they provide a possible route for quantifying mosquito population structure and dynamics. For example, vertically transmitted viruses could behave as a rapidly evolving extension of the host's genome. It should be possible to apply established analytical methods to appropriate viral phylogenies and incidence data to generate novel approaches for estimating mosquito population structure and dispersal over epidemiologically relevant timescales. By studying the virome through the lens of spatial and genomic epidemiology, it may be possible to investigate otherwise cryptic aspects of mosquito ecology. A better understanding of mosquito population structure and dynamics are key for understanding mosquito-borne disease ecology and methods based on ISVs could provide a powerful tool for informing mosquito control programs.
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Affiliation(s)
- Brandon D Hollingsworth
- Department of Entomology, Cornell University, Ithaca, New York, United States of America
- Cornell Institute for Host Microbe Interaction and Disease, Cornell University, Ithaca, New York, United States of America
| | - Nathan D Grubaugh
- Yale School of Public Health, New Haven, Connecticut, United States of America
- Yale University, New Haven, Connecticut, United States of America
| | - Brian P Lazzaro
- Department of Entomology, Cornell University, Ithaca, New York, United States of America
- Cornell Institute for Host Microbe Interaction and Disease, Cornell University, Ithaca, New York, United States of America
| | - Courtney C Murdock
- Department of Entomology, Cornell University, Ithaca, New York, United States of America
- Cornell Institute for Host Microbe Interaction and Disease, Cornell University, Ithaca, New York, United States of America
- Northeast Regional Center for Excellence in Vector-borne Diseases, Cornell University, Ithaca, New York, United States of America
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3
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Peinado SA, Aliota MT, Blitvich BJ, Bartholomay LC. Biology and Transmission Dynamics of Aedes flavivirus. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:659-666. [PMID: 35064663 PMCID: PMC8924967 DOI: 10.1093/jme/tjab197] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Indexed: 05/08/2023]
Abstract
Aedes albopictus (Skuse) and Aedes aegypti (Linnaeus) (Diptera: Culicidae) mosquitoes transmit pathogenic arthropod-borne viruses, including dengue, chikungunya, and Zika viruses, with significant global health consequences. Both Ae. albopictus and Ae. aegypti also are susceptible to Aedes flavivirus (AEFV), an insect-specific flavivirus (ISF) first isolated in Japan from Ae. albopictus and Ae. flavopictus. ISFs infect only insect hosts and evidence suggests that they are maintained by vertical transmission. In some cases, ISFs interfere with pathogenic flavivirus infection, and may have potential use in disease control. We explored the host range of AEFV in 4 genera of mosquitoes after intrathoracic injection and observed greater than 95% prevalence in the species of Aedes and Toxorhynchites tested. Anopheles and Culex species were less permissive to infection. Vertical transmission studies revealed 100% transovarial transmission and a filial infection rate of 100% for AEFV in a persistently-infected colony of Ae. albopictus. Horizontal transmission potential was assessed for adult and larval mosquitoes following per os exposures and in venereal transmission experiments. No mosquitoes tested positive for AEFV infection after blood feeding, and infection with AEFV after sucrose feeding was rare. Similarly, 2% of adult mosquitoes tested positive for AEFV after feeding on infected cells in culture as larvae. Venereal transmission of AEFV was most frequently observed from infected males to uninfected females as compared with transmission from infected females to uninfected males. These results reveal new information on the infection potential of AEFV in mosquitoes and expand our understanding of both vertical and horizontal transmission of ISFs.
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Affiliation(s)
- Stephen A Peinado
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA
| | - Matthew T Aliota
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Twin Cities, MN, USA
| | - Bradley J Blitvich
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Lyric C Bartholomay
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA
- Corresponding author, e-mail:
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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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To Kill or to Repel Mosquitoes? Exploring Two Strategies for Protecting Humans and Reducing Vector-Borne Disease Risks by Using Pyrethroids as Spatial Repellents. Pathogens 2021; 10:pathogens10091171. [PMID: 34578203 PMCID: PMC8471886 DOI: 10.3390/pathogens10091171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/01/2021] [Accepted: 09/07/2021] [Indexed: 11/29/2022] Open
Abstract
Although control efforts are improving, vector-borne diseases remain a global public health challenge. There is a need to shift vector control paradigms while developing new products and programmes. The importance of modifying vector behaviour has been recognised for decades but has received limited attention from the public health community. This study aims to: (1) explore how the use of spatial repellents at sublethal doses could promote public health worldwide; (2) propose new methods for evaluating insecticides for use by the general public; and (3) identify key issues to address before spatial repellents can be adopted as complementary vector control tools. Two field experiments were performed to assess the effects of an insecticidal compound, the pyrethroid transfluthrin, on Aedes albopictus mosquitoes. The first examined levels of human protection, and the second looked at mosquito knockdown and mortality. For the same transfluthrin dose and application method, the percent protection remained high (>80%) at 5 h even though mosquito mortality had declined to zero at 1 h. This result underscores that it matters which evaluation parameters are chosen. If the overarching goal is to decrease health risks, sublethal doses could be useful as they protect human hosts even when mosquito mortality is null.
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Chiuya T, Masiga DK, Falzon LC, Bastos ADS, Fèvre EM, Villinger J. A survey of mosquito-borne and insect-specific viruses in hospitals and livestock markets in western Kenya. PLoS One 2021; 16:e0252369. [PMID: 34048473 PMCID: PMC8162702 DOI: 10.1371/journal.pone.0252369] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 05/15/2021] [Indexed: 11/18/2022] Open
Abstract
Aedes aegypti and Culex pipiens complex mosquitoes are prolific vectors of arboviruses that are a global threat to human and animal health. Increased globalization and ease of travel have facilitated the worldwide dissemination of these mosquitoes and the viruses they transmit. To assess disease risk, we determined the frequency of arboviruses in western Kenyan counties bordering an area of high arboviral activity. In addition to pathogenic viruses, insect-specific flaviviruses (ISFs), some of which are thought to impair the transmission of specific pathogenic arboviruses, were also evaluated. We trapped mosquitoes in the short and long rainy seasons in 2018 and 2019 at livestock markets and hospitals. Mosquitoes were screened for dengue, chikungunya and other human pathogenic arboviruses, ISFs, and their blood-meal sources as determined by high-resolution melting analysis of (RT-)PCR products. Of 6,848 mosquitoes collected, 89% were trapped during the long rainy season, with A. aegypti (59%) and Cx. pipiens sensu lato (40%) being the most abundant. Most blood-fed mosquitoes were Cx. pipiens s.l. with blood-meals from humans, chicken, and sparrow (Passer sp.). We did not detect dengue or chikungunya viruses. However, one Culex poicilipes female was positive for Sindbis virus, 30 pools of Ae. aegypti had cell fusing agent virus (CFAV; infection rate (IR) = 1.27%, 95% CI = 0.87%-1.78%); 11 pools of Ae. aegypti had Aedes flavivirus (AeFV; IR = 0.43%, 95% CI = 0.23%-0.74%); and seven pools of Cx. pipiens s.l. (IR = 0.23%, 95% CI = 0.1%-0.45%) and one pool of Culex annulioris had Culex flavivirus. Sindbis virus, which causes febrile illness in humans, can complicate the diagnosis and prognosis of patients with fever. The presence of Sindbis virus in a single mosquito from a population of mosquitoes with ISFs calls for further investigation into the role ISFs may play in blocking transmission of other arboviruses in this region.
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Affiliation(s)
- Tatenda Chiuya
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
- * E-mail: , (TC); (JV)
| | - Daniel K. Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Laura C. Falzon
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, United Kingdom
- International Livestock Research Institute, Nairobi, Kenya
| | - Armanda D. S. Bastos
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Eric M. Fèvre
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, United Kingdom
- International Livestock Research Institute, Nairobi, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- * E-mail: , (TC); (JV)
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Moreno-Gómez M, Bueno-Marí R, Drago A, Miranda MA. From the Field to the Laboratory: Quantifying Outdoor Mosquito Landing Rate to Better Evaluate Topical Repellents. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:1287-1297. [PMID: 33458778 DOI: 10.1093/jme/tjaa298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Indexed: 06/12/2023]
Abstract
Vector-borne diseases are a worldwide threat to human health. Often, no vaccines or treatments exist. Thus, personal protection products play an essential role in limiting transmission. The World Health Organization (WHO) arm-in-cage (AIC) test is the most common method for evaluating the efficacy of topical repellents, but it remains unclear whether AIC testing conditions recreate the mosquito landing rates in the field. This study aimed to estimate the landing rate outdoors, in an area of Europe highly infested with the Asian tiger mosquito (Aedes albopictus (Skuse, 1894, Diptera: Culididae)), and to determine how to replicate this rate in the laboratory. To assess the landing rate in the field, 16 individuals were exposed to mosquitoes in a highly infested region of Italy. These field results were then compared to results obtained in the laboratory: 1) in a 30 m3 room where nine volunteers were exposed to different mosquito abundances (ranges: 15-20, 25-30, and 45-50) and 2) in a 0.064 m3 AIC test cage where 10 individuals exposed their arms to 200 mosquitoes (as per WHO requirements). The highest mosquito landing rate in the field was 26.8 landings/min. In the room test, a similar landing rate was achieved using 15-20 mosquitoes (density: 0.50-0.66 mosquitoes/m3) and an exposure time of 3 min. In the AIC test using 200 mosquitoes (density: 3,125 mosquitoes/m3), the landing rate was 229 ± 48 landings/min. This study provides useful reference values that can be employed to design new evaluation standards for topical repellents that better simulate field conditions.
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Affiliation(s)
- Mara Moreno-Gómez
- Henkel Ibérica S.A, Research and Development (R&D) Insect Control Department, Barcelona, Spain
| | - Rubén Bueno-Marí
- Laboratorios Lokímica, Departamento de Investigación y Desarrollo (I+D), Valencia, Spain
- Àrea de Parasitologia, Departament de Farmàcia i Tecnologia Farmacèutica i Parasitologia, Universitat de València, València, Spain
| | | | - Miguel A Miranda
- Applied Zoology and Animal Conservation Research Group, UIB, Palma de Mallorca, Spain
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Kobayashi D, Watanabe M, Faizah AN, Amoa-Bosompem M, Higa Y, Tsuda Y, Sawabe K, Isawa H. Discovery of a Novel Flavivirus (Flaviviridae) From the Horse Fly, Tabanus rufidens (Diptera: Tabanidae): The Possible Coevolutionary Relationships Between the Classical Insect-Specific Flaviviruses and Host Dipteran Insects. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:880-890. [PMID: 33710314 DOI: 10.1093/jme/tjaa193] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Indexed: 06/12/2023]
Abstract
Tabanid flies (Tabanidae: Diptera) are common hematophagous insects known to transmit some pathogens mechanically or biologically to animals; they are widely distributed throughout the world. However, no tabanid-borne viruses, except mechanically transmitted viruses, have been reported to date. In this study, we conducted RNA virome analysis of several human-biting tabanid species in Japan, to discover and characterize viruses associated with tabanids. A novel flavivirus was encountered during the study in the Japanese horse fly, Tabanus rufidens (Bigot, 1887). The virus was detected only in T. rufidens, but not in other tabanid species, and as such was designated Tabanus rufidens flavivirus (TrFV). TrFV could not be isolated using a mammalian cell line and showed a closer phylogenetic relationship to the classical insect-specific flaviviruses (cISFs) rather than the vertebrate-infecting flaviviruses (VIFs), suggesting that it is a novel member of the cISFs. The first discovery of a cISF from Brachycera provides new insight into the evolutionary history and dynamics of flaviviruses.
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Affiliation(s)
- Daisuke Kobayashi
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
- Department of Research Promotion, Japan Agency for Medical Research and Development, Otemachi, Chiyoda-ku, Tokyo, Japan
| | - Mamoru Watanabe
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Astri Nur Faizah
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Michael Amoa-Bosompem
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Yukiko Higa
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Yoshio Tsuda
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Kyoko Sawabe
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Haruhiko Isawa
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
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Kubacki J, Flacio E, Qi W, Guidi V, Tonolla M, Fraefel C. Viral Metagenomic Analysis of Aedes albopictus Mosquitos from Southern Switzerland. Viruses 2020; 12:v12090929. [PMID: 32846980 PMCID: PMC7552062 DOI: 10.3390/v12090929] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/17/2020] [Accepted: 08/19/2020] [Indexed: 02/07/2023] Open
Abstract
A metagenomic study was performed on 498 female and 40 male Aedes albopictus mosquitos collected in August and September 2019 in Ticino, a region in southern Switzerland, to address the question regarding the risk of the local transmission of zoonotic viruses. A total of 13 viruses from seven different virus families and several unclassified viral taxa were identified. Reads of insect-specific flaviviruses were present in all pools, and a complete genome of aedes flavivirus was assembled and phylogenetically analysed. The most abundant virus was Wenzhou sobemo-like virus, assembled from 1.3 × 105 to 3.6 × 106 reads in each pool. In a pool of male mosquitos, a complete genome of aedes Iflavi-like virus was detected and phylogenetically analysed. Most importantly, genomes of human pathogenic viruses were not found. This is the first study to determine the virome of Ae. albopictus from Switzerland and forms a baseline for future longitudinal investigations concerning the potential role of Ae. albopictus as a vector of clinically relevant viruses.
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Affiliation(s)
- Jakub Kubacki
- Institute of Virology, University of Zürich, CH-8057 Zürich, Switzerland
- Correspondence: (J.K.); (C.F.)
| | - Eleonora Flacio
- Laboratory of Applied Microbiology, Department for Environment Constructions and Design, University of Applied Sciences and Arts of Southern Switzerland, CH-6500 Manno, Switzerland; (E.F.); (V.G.); (M.T.)
| | - Weihong Qi
- Functional Genomics Center Zurich, CH-8057 Zürich, Switzerland;
| | - Valeria Guidi
- Laboratory of Applied Microbiology, Department for Environment Constructions and Design, University of Applied Sciences and Arts of Southern Switzerland, CH-6500 Manno, Switzerland; (E.F.); (V.G.); (M.T.)
| | - Mauro Tonolla
- Laboratory of Applied Microbiology, Department for Environment Constructions and Design, University of Applied Sciences and Arts of Southern Switzerland, CH-6500 Manno, Switzerland; (E.F.); (V.G.); (M.T.)
| | - Cornel Fraefel
- Institute of Virology, University of Zürich, CH-8057 Zürich, Switzerland
- Correspondence: (J.K.); (C.F.)
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Gomulski LM, Manni M, Carraretto D, Nolan T, Lawson D, Ribeiro JM, Malacrida AR, Gasperi G. Transcriptional variation of sensory-related genes in natural populations of Aedes albopictus. BMC Genomics 2020; 21:547. [PMID: 32767966 PMCID: PMC7430840 DOI: 10.1186/s12864-020-06956-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/27/2020] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The Asian tiger mosquito, Aedes albopictus, is a highly dangerous invasive vector of numerous medically important arboviruses including dengue, chikungunya and Zika. In four decades it has spread from tropical Southeast Asia to many parts of the world in both tropical and temperate climes. The rapid invasion process of this mosquito is supported by its high ecological and genetic plasticity across different life history traits. Our aim was to investigate whether wild populations, both native and adventive, also display transcriptional genetic variability for functions that may impact their biology, behaviour and ability to transmit arboviruses, such as sensory perception. RESULTS Antennal transcriptome data were derived from mosquitoes from a native population from Ban Rai, Thailand and from three adventive Mediterranean populations: Athens, Greece and Arco and Trento from Italy. Clear inter-population differential transcriptional activity was observed in different gene categories related to sound perception, olfaction and viral infection. The greatest differences were detected between the native Thai and the Mediterranean populations. The two Italian populations were the most similar. Nearly one million quality filtered SNP loci were identified. CONCLUSION The ability to express this great inter-population transcriptional variability highlights, at the functional level, the remarkable genetic flexibility of this mosquito species. We can hypothesize that the differential expression of genes, including those involved in sensory perception, in different populations may enable Ae. albopictus to exploit different environments and hosts, thus contributing to its status as a global vector of arboviruses of public health importance. The large number of SNP loci present in these transcripts represents a useful addition to the arsenal of high-resolution molecular markers and a resource that can be used to detect selective pressure and adaptive changes that may have occurred during the colonization process.
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Affiliation(s)
- Ludvik M Gomulski
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Mosè Manni
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
- Department of Genetic Medicine and Development, University of Geneva Medical School, and Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Davide Carraretto
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Tony Nolan
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Daniel Lawson
- Department of Life Sciences, Imperial College London, London, UK
| | - José M Ribeiro
- NIAID, Laboratory of Malaria and Vector Research, NIH, Rockville, MD, 20852, USA
| | - Anna R Malacrida
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Giuliano Gasperi
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy.
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Patterson EI, Villinger J, Muthoni JN, Dobel-Ober L, Hughes GL. Exploiting insect-specific viruses as a novel strategy to control vector-borne disease. CURRENT OPINION IN INSECT SCIENCE 2020; 39:50-56. [PMID: 32278312 PMCID: PMC7302987 DOI: 10.1016/j.cois.2020.02.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/30/2020] [Accepted: 02/17/2020] [Indexed: 05/03/2023]
Abstract
Novel insect-specific viruses (ISVs) are being discovered in many important vectors due to advances in sequencing technology and a growing awareness of the virome. Several in vitro and in vivo studies indicate that ISVs are capable of modulating pathogenic arboviruses. In addition, there is growing evidence that both vertical and horizonal transmission strategies maintain ISVs in vector populations. As such there is potential to exploit ISVs for stand-alone vector control strategies and deploying them in synergy with other symbiont control approaches such as Wolbachia-mediated control. However, before the applied potential can be realized, a greater understanding of their basic biology is required, including their species range, ability to be maintained and transmitted in native and non-native vector hosts, and the effect of infection on a range of pathogens.
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Affiliation(s)
- Edward I Patterson
- Centre for Neglected Tropical Diseases, Departments of Vector Biology and Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK.
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Joseph N Muthoni
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Lucien Dobel-Ober
- Centre for Neglected Tropical Diseases, Departments of Vector Biology and Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Grant L Hughes
- Centre for Neglected Tropical Diseases, Departments of Vector Biology and Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
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Supriyono, Kuwata R, Torii S, Shimoda H, Ishijima K, Yonemitsu K, Minami S, Kuroda Y, Tatemoto K, Tran NTB, Takano A, Omatsu T, Mizutani T, Itokawa K, Isawa H, Sawabe K, Takasaki T, Yuliani DM, Abiyoga D, Hadi UK, Setiyono A, Hondo E, Agungpriyono S, Maeda K. Mosquito-borne viruses, insect-specific flaviviruses (family Flaviviridae, genus Flavivirus), Banna virus (family Reoviridae, genus Seadornavirus), Bogor virus (unassigned member of family Permutotetraviridae), and alphamesoniviruses 2 and 3 (family Mesoniviridae, genus Alphamesonivirus) isolated from Indonesian mosquitoes. J Vet Med Sci 2020; 82:1030-1041. [PMID: 32448813 PMCID: PMC7399325 DOI: 10.1292/jvms.20-0261] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mosquitoes transmit many kinds of arboviruses (arthropod-borne viruses), and numerous arboviral diseases have become serious problems in Indonesia. In this study, we conducted surveillance of mosquito-borne viruses at several sites in Indonesia during 2016-2018 for risk assessment of arbovirus infection and analysis of virus biodiversity in mosquito populations. We collected 10,015 mosquitoes comprising at least 11 species from 4 genera. Major collected mosquito species were Culex quinquefasciatus, Aedes albopictus, Culex tritaeniorhynchus, Aedes aegypti, and Armigeres subalbatus. The collected mosquitoes were divided into 285 pools and used for virus isolation using two mammalian cell lines, Vero and BHK-21, and one mosquito cell line, C6/36. Seventy-two pools showed clear cytopathic effects only in C6/36 cells. Using RT-PCR and next-generation sequencing approaches, these isolates were identified as insect flaviviruses (family Flaviviridae, genus Flavivirus), Banna virus (family Reoviridae, genus Seadornavirus), new permutotetravirus (designed as Bogor virus) (family Permutotetraviridae, genus Alphapermutotetravirus), and alphamesoniviruses 2 and 3 (family Mesoniviridae, genus Alphamesonivirus). We believed that this large surveillance of mosquitoes and mosquito-borne viruses provides basic information for the prevention and control of emerging and re-emerging arboviral diseases.
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Affiliation(s)
- Supriyono
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan
| | - Ryusei Kuwata
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.,Faculty of Veterinary Medicine, Okayama University of Science, 1-3 Ikoino-oka, Imabari, Ehime 794-8555, Japan
| | - Shun Torii
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan
| | - Hiroshi Shimoda
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan
| | - Keita Ishijima
- Department of Veterinary Science, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Kenzo Yonemitsu
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan
| | - Shohei Minami
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan
| | - Yudai Kuroda
- Department of Veterinary Science, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Kango Tatemoto
- Department of Veterinary Science, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Ngo Thuy Bao Tran
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan
| | - Ai Takano
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan
| | - Tsutomu Omatsu
- Research and Education Center for Prevention of Global Infectious Diseases of Animals, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8508, Japan
| | - Tetsuya Mizutani
- Research and Education Center for Prevention of Global Infectious Diseases of Animals, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8508, Japan
| | - Kentaro Itokawa
- Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Haruhiko Isawa
- Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Kyoko Sawabe
- Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Tomohiko Takasaki
- Kanagawa Prefectural Institute of Public Health, 1-3-1 Shimomachiya, Chigasaki, Kanagawa 253-0087, Japan
| | - Dewi Maria Yuliani
- Public Health Office of Tangerang District, Tigaraksa Subdistrict, Banten 15720, Indonesia
| | - Dimas Abiyoga
- Indonesian Research Center for Veterinary Sciences, Sesetan, Denpasar City, Bali 80223, Indonesia
| | - Upik Kesumawati Hadi
- Faculty of Veterinary Medicine, IPB University, Kampus IPB Dramaga, Bogor 16680, West Java, Indonesia
| | - Agus Setiyono
- Faculty of Veterinary Medicine, IPB University, Kampus IPB Dramaga, Bogor 16680, West Java, Indonesia
| | - Eiichi Hondo
- Department of Biological Mechanisms and Function, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Srihadi Agungpriyono
- Faculty of Veterinary Medicine, IPB University, Kampus IPB Dramaga, Bogor 16680, West Java, Indonesia
| | - Ken Maeda
- Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.,Department of Veterinary Science, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
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Abstract
Usutu virus (USUV) is an emerging arbovirus that was first isolated in South Africa in 1959. This Flavivirus is maintained in the environment through a typical enzootic cycle involving mosquitoes and birds. USUV has spread to a large part of the European continent over the two decades mainly leading to substantial avian mortalities with a significant recrudescence of bird infections recorded throughout Europe within the few last years. USUV infection in humans is considered to be most often asymptomatic or to cause mild clinical signs. Nonetheless, a few cases of neurological complications such as encephalitis or meningoencephalitis have been reported. USUV and West Nile virus (WNV) share many features, like a close phylogenetic relatedness and a similar ecology, with co-circulation frequently observed in nature. However, USUV has been much less studied and in-depth comparisons of the biology of these viruses are yet rare. In this review, we discuss the main body of knowledge regarding USUV and compare it with the literature on WNV, addressing in particular virological and clinical aspects, and pointing data gaps.
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14
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Akıner MM, Öztürk M, Başer AB, Günay F, Hacıoğlu S, Brinkmann A, Emanet N, Alten B, Özkul A, Nitsche A, Linton YM, Ergünay K. Arboviral screening of invasive Aedes species in northeastern Turkey: West Nile virus circulation and detection of insect-only viruses. PLoS Negl Trop Dis 2019; 13:e0007334. [PMID: 31059502 PMCID: PMC6522068 DOI: 10.1371/journal.pntd.0007334] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 05/16/2019] [Accepted: 03/26/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The recent reports of Aedes aegypti and Ae. albopictus populations in Turkey, in parallel with the territorial expansion identified in several surrounding countries, have raised concerns about the establishment and re-establishment of these invasive Aedes mosquitoes in Turkey. This cross-sectional study was performed to detect Aedes aegypti and Ae. albopictus in regions of recent incursions, and screen for viral pathogens known to be transmitted elsewhere by these species. METHODOLOGY Mosquitoes were collected at several locations in Artvin, Rize and Trabzon provinces of the Black Sea region during 2016-2017, identified morphologically, pooled and analyzed via generic or specific nucleic acid amplification assays. Viruses in positive pools were identified by product sequencing, cell culture inoculation and next generation sequencing (NGS) in selected specimens. PRINCIPAL FINDINGS The study group comprised 791 specimens. Aedes albopictus was the most abundant species in all locations (89.6%), followed by Ae. aegypti (7.8%) and Culex pipiens (2.5%). Mosquitoes were screened for viruses in 65 pools where fifteen (23.1%) were reactive. The infecting strains was identified as West Nile virus (WNV) in 5 pools (7.7%) with Ae. albopictus or Cx. pipiens mosquitoes. The obtained WNV sequences phylogenetically grouped with local and global lineage 1 clade 1a viruses. In 4 (6.2%) and 6 (9.2%) pools, respectively, cell fusing agent virus (CFAV) and Aedes flavivirus (AEFV) sequences were characterized. NGS provided a near-complete AEFV genome in a pool of Ae. albopictus. The strain is provisionally called "AEFV-Turkey", and functional analysis of the genome revealed several conserved motifs and regions associated with virus replication. Merida-like virus Turkey (MERDLVT), a recently-described novel rhabdovirus, was also co-detected in a Cx. pipiens pool also positive for WNV. CONCLUSIONS/SIGNIFICANCE Invasive Aedes mosquitoes are established in certain locations of northeastern Turkey. Herein we conclusively show the role of these species in WNV circulation in the region. Biosurveillance is imperative to monitor the spread of these species further into Asia Minor and to detect possible introduction of pathogens.
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Affiliation(s)
- Mustafa M. Akıner
- Recep Tayyip Erdogan University, Faculty of Arts and Sciences, Department of Biology, Rize, TURKEY
| | - Murat Öztürk
- Recep Tayyip Erdogan University, Faculty of Arts and Sciences, Department of Biology, Rize, TURKEY
| | - Aykut Buğra Başer
- Recep Tayyip Erdogan University, Faculty of Arts and Sciences, Department of Biology, Rize, TURKEY
| | - Filiz Günay
- Hacettepe University; Faculty of Sciences, Department of Biology, Division of Ecology, Ankara, TURKEY
| | - Sabri Hacıoğlu
- Ankara University; Faculty of Veterinary Medicine, Department of Virology, Ankara, TURKEY
| | - Annika Brinkmann
- Robert Koch Institute; Center for Biological Threats and Special Pathogens 1 (ZBS-1), Berlin, GERMANY
| | - Nergis Emanet
- Hacettepe University; Faculty of Medicine, Department of Medical Microbiology, Virology Unit, Ankara, TURKEY
| | - Bülent Alten
- Hacettepe University; Faculty of Sciences, Department of Biology, Division of Ecology, Ankara, TURKEY
| | - Aykut Özkul
- Ankara University; Faculty of Veterinary Medicine, Department of Virology, Ankara, TURKEY
| | - Andreas Nitsche
- Robert Koch Institute; Center for Biological Threats and Special Pathogens 1 (ZBS-1), Berlin, GERMANY
| | - Yvonne-Marie Linton
- Department of Entomology, National Museum of Natural History, Smithsonian Institution, Washington, United States of America
- Walter Reed Biosystematics Unit, Smithsonian Institution Museum Support Center, Suitland, United States of America
| | - Koray Ergünay
- Hacettepe University; Faculty of Medicine, Department of Medical Microbiology, Virology Unit, Ankara, TURKEY
- * E-mail:
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15
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Ajamma YU, Onchuru TO, Ouso DO, Omondi D, Masiga DK, Villinger J. Vertical transmission of naturally occurring Bunyamwera and insect-specific flavivirus infections in mosquitoes from islands and mainland shores of Lakes Victoria and Baringo in Kenya. PLoS Negl Trop Dis 2018; 12:e0006949. [PMID: 30452443 PMCID: PMC6287884 DOI: 10.1371/journal.pntd.0006949] [Citation(s) in RCA: 26] [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: 05/03/2018] [Revised: 12/10/2018] [Accepted: 10/26/2018] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Many arboviruses transmitted by mosquitoes have been implicated as causative agents of both human and animal illnesses in East Africa. Although epidemics of arboviral emerging infectious diseases have risen in frequency in recent years, the extent to which mosquitoes maintain pathogens in circulation during inter-epidemic periods is still poorly understood. This study aimed to investigate whether arboviruses may be maintained by vertical transmission via immature life stages of different mosquito vector species. METHODOLOGY We collected immature mosquitoes (egg, larva, pupa) on the shores and islands of Lake Baringo and Lake Victoria in western Kenya and reared them to adults. Mosquito pools (≤25 specimens/pool) of each species were screened for mosquito-borne viruses by high-resolution melting analysis and sequencing of multiplex PCR products of genus-specific primers (alphaviruses, flaviviruses, phleboviruses and Bunyamwera-group orthobunyaviruses). We further confirmed positive samples by culturing in baby hamster kidney and Aedes mosquito cell lines and re-sequencing. PRINCIPAL FINDINGS Culex univittatus (2/31pools) and Anopheles gambiae (1/77 pools) from the Lake Victoria region were positive for Bunyamwera virus, a pathogenic virus that is of public health concern. In addition, Aedes aegypti (3/50), Aedes luteocephalus (3/13), Aedes spp. (2/15), and Culex pipiens (1/140) pools were positive for Aedes flaviviruses at Lake Victoria, whereas at Lake Baringo, three pools of An. gambiae mosquitoes were positive for Anopheles flavivirus. These insect-specific flaviviruses (ISFVs), which are presumably non-pathogenic to vertebrates, were found in known medically important arbovirus and malaria vectors. CONCLUSIONS Our results suggest that not only ISFVs, but also a pathogenic arbovirus, are naturally maintained within mosquito populations by vertical transmission, even in the absence of vertebrate hosts. Therefore, virus and vector surveillance, even during inter-epidemics, and the study of vector-arbovirus-ISFV interactions, may aid in identifying arbovirus transmission risks, with the potential to inform control strategies that lead to disease prevention.
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Affiliation(s)
| | - Thomas Ogao Onchuru
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Department of Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
| | - Daniel O. Ouso
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - David Omondi
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Biochemistry and Molecular Biology Department, Egerton University, Egerton, Kenya
| | - Daniel K. Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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16
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Mosquito-only flaviviruses, isolated from Aedes albopictus in Slovenia: results of a pilot mosquito monitoring program. Biologia (Bratisl) 2018. [DOI: 10.2478/s11756-018-0135-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Romeo C, Lecollinet S, Caballero J, Isla J, Luzzago C, Ferrari N, García-Bocanegra I. Are tree squirrels involved in the circulation of flaviviruses in Italy? Transbound Emerg Dis 2018; 65:1372-1376. [PMID: 29635877 DOI: 10.1111/tbed.12874] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Indexed: 11/30/2022]
Abstract
West Nile virus (WNV), Usutu virus (USUV) and tick-borne encephalitis virus (TBEV) are emerging zoonotic flaviviruses (family Flaviviridae), which have circulated in Europe in the past decade. A cross-sectional study was conducted to assess exposure to these antigenically related flaviviruses in eastern grey squirrels (Sciurus carolinensis) in Italy. Seventeen out of 158 (10.8%; CI95% : 5.9-15.6) squirrels' sera tested through bELISA had antibodies against flaviviruses. Specific neutralizing antibodies to WNV, USUV and TBEV were detected by virus neutralization tests. Our results indicate that tree squirrels are exposed to Culex and tick-borne zoonotic flaviviruses in Italy. Moreover, this study shows for the first time USUV and TBEV exposure in grey squirrels, broadening the host range reported for these viruses. Even though further studies are needed to define the real role of tree squirrels in the epidemiology of flaviviruses in Europe, this study highlights that serology could be an effective approach for future investigations aimed at broadening our knowledge about the species exposed to these zoonotic infections.
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Affiliation(s)
- C Romeo
- Department of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy
| | - S Lecollinet
- Laboratoire de Santé Animale de Maisons-Alfort, UMR 1161 Virologie, INRA, ANSES, ENVA, Maisons-Alfort, France
| | - J Caballero
- Facultad de Veterinaria, Departamento de Sanidad Animal, Universidad de Córdoba-Agrifood Excellence International, Córdoba, Spain
| | - J Isla
- Facultad de Veterinaria, Departamento de Sanidad Animal, Universidad de Córdoba-Agrifood Excellence International, Córdoba, Spain
| | - C Luzzago
- Department of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy.,Coordinated Research Center "EpiSoMI", Università degli Studi di Milano, Milan, Italy
| | - N Ferrari
- Department of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy.,Coordinated Research Center "EpiSoMI", Università degli Studi di Milano, Milan, Italy
| | - I García-Bocanegra
- Facultad de Veterinaria, Departamento de Sanidad Animal, Universidad de Córdoba-Agrifood Excellence International, Córdoba, Spain
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18
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Villinger J, Mbaya MK, Ouso D, Kipanga PN, Lutomiah J, Masiga DK. Arbovirus and insect-specific virus discovery in Kenya by novel six genera multiplex high-resolution melting analysis. Mol Ecol Resour 2016; 17:466-480. [PMID: 27482633 DOI: 10.1111/1755-0998.12584] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Revised: 07/02/2016] [Accepted: 07/05/2016] [Indexed: 02/03/2023]
Abstract
A broad diversity of arthropod-borne viruses (arboviruses) of global health concern are endemic to East Africa, yet most surveillance efforts are limited to just a few key viral pathogens. Additionally, estimates of arbovirus diversity in the tropics are likely to be underestimated as their discovery has lagged significantly over past decades due to limitations in fast and sensitive arbovirus identification methods. Here, we developed a nearly pan-arbovirus detection assay that uses high-resolution melting (HRM) analysis of RT-PCR products from highly multiplexed assays to differentiate broad diversities of arboviruses. We differentiated 15 viral culture controls and seven additional synthetic viral DNA sequence controls, within Flavivirus, Alphavirus, Nairovirus, Phlebovirus, Orthobunyavirus and Thogotovirus genera. Among Bunyamwera, sindbis, dengue and Thogoto virus serial dilutions, detection by multiplex RT-PCR-HRM was comparable to the gold standard Vero cell plaque assays. We applied our low-cost method for enhanced broad-range pathogen surveillance from mosquito samples collected in Kenya and identified diverse insect-specific viruses, including a new clade in anopheline mosquitoes, and Wesselsbron virus, an arbovirus that can cause viral haemorrhagic fever in humans and has not previously been isolated in Kenya, in Culex spp. and Anopheles coustani mosquitoes. Our findings demonstrate how multiplex RT-PCR-HRM can identify novel viral diversities and potential disease threats that may not be included in pathogen detection panels of routine surveillance efforts. This approach can be adapted to other pathogens to enhance disease surveillance and pathogen discovery efforts, as well as the study of pathogen diversity and viral evolutionary ecology.
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Affiliation(s)
- Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya
| | - Martin K Mbaya
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya.,Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000, Nairobi, Kenya
| | - Daniel Ouso
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya.,Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000, Nairobi, Kenya
| | - Purity N Kipanga
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya.,Zoological Institute, Katholieke Universiteit, Naamsestraat 59, P.O. Box 3000, Leuven, Belgium
| | - Joel Lutomiah
- Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
| | - Daniel K Masiga
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya
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19
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Vázquez A, Herrero L, Negredo A, Hernández L, Sánchez-Seco MP, Tenorio A. Real time PCR assay for detection of all known lineages of West Nile virus. J Virol Methods 2016; 236:266-270. [PMID: 27481597 DOI: 10.1016/j.jviromet.2016.07.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 07/29/2016] [Accepted: 07/29/2016] [Indexed: 11/17/2022]
Abstract
West Nile virus (WNV) is one of the most widespread arbovirus and a large variety of WNV strains and lineages have been described. The molecular methods for the diagnosis of WNV target mainly lineages 1 and 2, which have caused outbreaks in humans, equines and birds. But the last few years new and putative WNV lineages of unknown pathogenicity have been described. Here we describe a new sensitive and specific real-time PCR assay for the detection and quantification of all the WNV lineages described until now. Primers and probe were designed in the 3'-untranslated region (3'-UTR) of the WNV genome and were designed to match all sequenced WNV strains perfectly. The sensitivity of the assay ranged from 1,5 to 15 copies per reaction depending on the WNV lineage tested. The method was validated for WNV diagnosis using different viral strains, human samples (cerebrospinal fluid, biopsies, serum and plasma) and mosquito pools. The assay did not amplify any other phylogenetically or symptomatically related viruses. All of the above make it a very suitable tool for the diagnosis of WNV and for surveillance studies.
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Affiliation(s)
- Ana Vázquez
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain.
| | - Laura Herrero
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - Anabel Negredo
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - Lourdes Hernández
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - María Paz Sánchez-Seco
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - Antonio Tenorio
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
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20
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Vascellari M, Ravagnan S, Carminato A, Cazzin S, Carli E, Da Rold G, Lucchese L, Natale A, Otranto D, Capelli G. Exposure to vector-borne pathogens in candidate blood donor and free-roaming dogs of northeast Italy. Parasit Vectors 2016; 9:369. [PMID: 27357128 PMCID: PMC4928314 DOI: 10.1186/s13071-016-1639-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 06/10/2016] [Indexed: 11/29/2022] Open
Abstract
Background Many vector-borne pathogens including viruses, bacteria, protozoa and nematodes occur in northeast Italy, representing a potential threat to animal and human populations. Little information is available on the circulation of the above vector-borne pathogens in dogs. This work aims to (i) assess exposure to and circulation of pathogens transmitted to dogs in northeast Italy by ticks, sandflies, and mosquitoes, and (ii) drive blood donor screening at the newly established canine blood bank of the Istituto Zooprofilattico Sperimentale delle Venezie. Methods Blood samples from 150 privately-owned canine candidate blood donors and 338 free-roaming dogs were screened by serology (IFA for Leishmania infantum, Ehrlichia canis, Anaplasma phagocythophilum, Babesia canis, Rickettsia conorii, R. rickettsii), microscopic blood smear examination, and blood filtration for Dirofilaria spp. All candidate donors and seropositive free-roaming dogs were tested by PCR for L. infantum, E. canis, A. phagocythophilum, Babesia/Theileria and Rickettsia spp. The dogs had no clinical signs at the time of sampling. Results Overall, 40 candidate donors (26.7 %) and 108 free-roaming dogs (32 %) were seroreactive to at least one vector-borne pathogen. Seroprevalence in candidate donors vs free-roaming dogs was: Leishmania infantum 6.7 vs 7.1 %; Anaplasma phagocytophilum 4.7 vs 3.3 %; Babesia canis 1.3 vs 2.7 %; Ehrlichia canis none vs 0.9 %; Rickettsia conorii 16 vs 21.3 % and R. rickettsii 11 vs 14.3 %. Seroreactivity to R. rickettsii, which is not reported in Italy, is likely a cross-reaction with other rickettsiae. Filariae, as Dirofilaria immitis (n = 19) and D. repens (n = 2), were identified in free-roaming dogs only. No significant differences were observed between candidate donors and free-roaming dogs either in the overall seroprevalence of vector-borne pathogens or for each individual pathogen. All PCRs and smears performed on blood were negative. Conclusions This study demonstrated that dogs are considerably exposed to vector-borne pathogens in northeast Italy. Although the dog owners reported regularly using ectoparasiticides against fleas and ticks, their dogs had similar exposure to vector-borne pathogens as free-roaming dogs. This prompts the need to improve owner education on the use of insecticidal and repellent compounds in order to reduce the risk of arthropod bites and exposure to vector-borne pathogens. Based on the absence of pathogens circulating in the blood of healthy dogs, the risk of transmission of these pathogens by blood transfusion seems to be low, depending also on the sensitivity of the tests used for screening.
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Affiliation(s)
- Marta Vascellari
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Silvia Ravagnan
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Antonio Carminato
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Stefania Cazzin
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Erika Carli
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Graziana Da Rold
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Laura Lucchese
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Alda Natale
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - Domenico Otranto
- Dipartimento di Medicina Veterinaria, Università degli Studi di Bari, Valenzano, Italy
| | - Gioia Capelli
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
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21
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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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Ecuador Paraiso Escondido Virus, a New Flavivirus Isolated from New World Sand Flies in Ecuador, Is the First Representative of a Novel Clade in the Genus Flavivirus. J Virol 2015; 89:11773-85. [PMID: 26355096 PMCID: PMC4645344 DOI: 10.1128/jvi.01543-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 09/04/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED A new flavivirus, Ecuador Paraiso Escondido virus (EPEV), named after the village where it was discovered, was isolated from sand flies (Psathyromyia abonnenci, formerly Lutzomyia abonnenci) that are unique to the New World. This represents the first sand fly-borne flavivirus identified in the New World. EPEV exhibited a typical flavivirus genome organization. Nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. Phylogenetic analysis of the complete coding sequence showed that EPEV represents a distinct clade which diverged from a lineage that was ancestral to the nonvectored flaviviruses Entebbe bat virus, Yokose virus, and Sokoluk virus and also the Aedes-associated mosquito-borne flaviviruses, which include yellow fever virus, Sepik virus, Saboya virus, and others. EPEV replicated in C6/36 mosquito cells, yielding high infectious titers, but failed to reproduce either in vertebrate cell lines (Vero, BHK, SW13, and XTC cells) or in suckling mouse brains. This surprising result, which appears to eliminate an association with vertebrate hosts in the life cycle of EPEV, is discussed in the context of the evolutionary origins of EPEV in the New World. IMPORTANCE The flaviviruses are rarely (if ever) vectored by sand fly species, at least in the Old World. We have identified the first representative of a sand fly-associated flavivirus, Ecuador Paraiso Escondido virus (EPEV), in the New World. EPEV constitutes a novel clade according to current knowledge of the flaviviruses. Phylogenetic analysis of the virus genome showed that EPEV roots the Aedes-associated mosquito-borne flaviviruses, including yellow fever virus. In light of this new discovery, the New World origin of EPEV is discussed together with that of the other flaviviruses.
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23
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Vasilakis N, Tesh RB. Insect-specific viruses and their potential impact on arbovirus transmission. Curr Opin Virol 2015; 15:69-74. [PMID: 26322695 DOI: 10.1016/j.coviro.2015.08.007] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 08/10/2015] [Accepted: 08/12/2015] [Indexed: 11/15/2022]
Abstract
Arthropod-borne viruses (arboviruses) are the causative agents of significant morbidity and mortality among humans and animals globally. In the past few years, the widespread adoption of next generation sequencing and metagenomics has led to a new era of virus discovery, where many novel viruses have been documented, exhibiting a restricted host-range in mosquitoes. They represent a wide-range of insect-specific viruses within the families of Bunyaviridae, Flaviviridae, Mesoniviridae, Reoviridae, Rhabdoviridae, Togaviridae, and the newly recognized taxon of Negeviruses. Collectively, their discovery has opened new vistas about the extent of viral diversity and evolution, their influence on vector competence and ability of their insect hosts to transmit human pathogens (e.g. arboviruses), and their potential development as biological control agents or novel vaccine platforms.
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Affiliation(s)
- Nikos Vasilakis
- Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, Center for Tropical Diseases, Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, TX 77555-0609, United States.
| | - Robert B Tesh
- Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, Center for Tropical Diseases, Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, TX 77555-0609, United States.
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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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25
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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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