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Smith DC, Schäfer SM, Golding N, Nunn MA, White SM, Callaghan A, Purse BV. Vegetation structure drives mosquito community composition in UK's largest managed lowland wetland. Parasit Vectors 2024; 17:201. [PMID: 38711091 DOI: 10.1186/s13071-024-06280-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Accepted: 04/13/2024] [Indexed: 05/08/2024] Open
Abstract
PURPOSE The rising burden of mosquito-borne diseases in Europe extends beyond urban areas, encompassing rural and semi-urban regions near managed and natural wetlands evidenced by recent outbreaks of Usutu and West Nile viruses. While wetland management policies focus on biodiversity and ecosystem services, few studies explore the impact on mosquito vectors. METHODS Our research addresses this gap, examining juvenile mosquito and aquatic predator communities in 67 ditch sites within a South England coastal marsh subjected to different wetland management tiers. Using joint distribution models, we analyse how mosquito communities respond to abiotic and biotic factors influenced by wetland management. RESULTS Of the 12 mosquito species identified, Culiseta annulata (Usutu virus vector) and Culex pipiens (Usutu and West Nile virus vector) constitute 47% of 6825 larval mosquitoes. Abundant predators include Coleoptera (water beetles) adults, Corixidae (water boatmen) and Zygoptera (Damselfy) larvae. Models reveal that tier 3 management sites (higher winter water levels, lower agricultural intensity) associated with shade and less floating vegetation are preferred by specific mosquito species. All mosquito species except Anopheles maculipennis s.l., are negatively impacted by potential predators. Culiseta annulata shows positive associations with shaded and turbid water, contrary to preferences of Corixidae predators. CONCLUSIONS Tier 3 areas managed for biodiversity, characterised by higher seasonal water levels and reduced livestock grazing intensity, provide favourable habitats for key mosquito species that are known vectors of arboviruses, such as Usutu and West Nile. Our findings emphasise the impact of biodiversity-focused wetland management, altering mosquito breeding site vegetation to enhance vector suitability. Further exploration of these trade-offs is crucial for comprehending the broader implications of wetland management.
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Affiliation(s)
- Daniel C Smith
- UK Centre for Ecology and Hydrology, MacLean Building, Wallingford, OX10 8BB, UK.
- School of Biological Sciences, University of Reading, Whiteknights, Reading, RG6 2AJ, UK.
| | - Stefanie M Schäfer
- UK Centre for Ecology and Hydrology, MacLean Building, Wallingford, OX10 8BB, UK
| | - Nick Golding
- UK Centre for Ecology and Hydrology, MacLean Building, Wallingford, OX10 8BB, UK
| | - Miles A Nunn
- UK Centre for Ecology and Hydrology, MacLean Building, Wallingford, OX10 8BB, UK
| | - Steven M White
- UK Centre for Ecology and Hydrology, MacLean Building, Wallingford, OX10 8BB, UK
| | - Amanda Callaghan
- School of Biological Sciences, University of Reading, Whiteknights, Reading, RG6 2AJ, UK
| | - Bethan V Purse
- UK Centre for Ecology and Hydrology, MacLean Building, Wallingford, OX10 8BB, UK
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2
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Cuervo PF, Artigas P, Lorenzo-Morales J, Bargues MD, Mas-Coma S. Ecological Niche Modelling Approaches: Challenges and Applications in Vector-Borne Diseases. Trop Med Infect Dis 2023; 8:tropicalmed8040187. [PMID: 37104313 PMCID: PMC10141209 DOI: 10.3390/tropicalmed8040187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/17/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023] Open
Abstract
Vector-borne diseases (VBDs) pose a major threat to human and animal health, with more than 80% of the global population being at risk of acquiring at least one major VBD. Being profoundly affected by the ongoing climate change and anthropogenic disturbances, modelling approaches become an essential tool to assess and compare multiple scenarios (past, present and future), and further the geographic risk of transmission of VBDs. Ecological niche modelling (ENM) is rapidly becoming the gold-standard method for this task. The purpose of this overview is to provide an insight of the use of ENM to assess the geographic risk of transmission of VBDs. We have summarised some fundamental concepts and common approaches to ENM of VBDS, and then focused with a critical view on a number of crucial issues which are often disregarded when modelling the niches of VBDs. Furthermore, we have briefly presented what we consider the most relevant uses of ENM when dealing with VBDs. Niche modelling of VBDs is far from being simple, and there is still a long way to improve. Therefore, this overview is expected to be a useful benchmark for niche modelling of VBDs in future research.
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Affiliation(s)
- Pablo Fernando Cuervo
- Departamento de Parasitologia, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andres Estelles s/n, 46100 Burjassot, Valencia, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos IIII, C/Monforte de Lemos 3-5. Pabellón 11, Planta 0, 28029 Madrid, Madrid, Spain
- Correspondence:
| | - Patricio Artigas
- Departamento de Parasitologia, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andres Estelles s/n, 46100 Burjassot, Valencia, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos IIII, C/Monforte de Lemos 3-5. Pabellón 11, Planta 0, 28029 Madrid, Madrid, Spain
| | - Jacob Lorenzo-Morales
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos IIII, C/Monforte de Lemos 3-5. Pabellón 11, Planta 0, 28029 Madrid, Madrid, Spain
- Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias, Universidad de La Laguna, Av. Astrofísico Fco. Sánchez s/n, 38203 La Laguna, Canary Islands, Spain
| | - María Dolores Bargues
- Departamento de Parasitologia, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andres Estelles s/n, 46100 Burjassot, Valencia, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos IIII, C/Monforte de Lemos 3-5. Pabellón 11, Planta 0, 28029 Madrid, Madrid, Spain
| | - Santiago Mas-Coma
- Departamento de Parasitologia, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andres Estelles s/n, 46100 Burjassot, Valencia, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos IIII, C/Monforte de Lemos 3-5. Pabellón 11, Planta 0, 28029 Madrid, Madrid, Spain
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3
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Giakountis A, Stylianidou Z, Zaka A, Pappa S, Papa A, Hadjichristodoulou C, Mathiopoulos KD. Development of Toehold Switches as a Novel Ribodiagnostic Method for West Nile Virus. Genes (Basel) 2023; 14:237. [PMID: 36672977 PMCID: PMC9859090 DOI: 10.3390/genes14010237] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
West Nile virus (WNV) is an emerging neurotropic RNA virus and a member of the genus Flavivirus. Naturally, the virus is maintained in an enzootic cycle involving mosquitoes as vectors and birds that are the principal amplifying virus hosts. In humans, the incubation period for WNV disease ranges from 3 to 14 days, with an estimated 80% of infected persons being asymptomatic, around 19% developing a mild febrile infection and less than 1% developing neuroinvasive disease. Laboratory diagnosis of WNV infection is generally accomplished by cross-reacting serological methods or highly sensitive yet expensive molecular approaches. Therefore, current diagnostic tools hinder widespread surveillance of WNV in birds and mosquitoes that serve as viral reservoirs for infecting secondary hosts, such as humans and equines. We have developed a synthetic biology-based method for sensitive and low-cost detection of WNV. This method relies on toehold riboswitches designed to detect WNV genomic RNA as transcriptional input and process it to GFP fluorescence as translational output. Our methodology offers a non-invasive tool with reduced operating cost and high diagnostic value that can be used for field surveillance of WNV in humans as well as in bird and mosquito populations.
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Affiliation(s)
- Antonis Giakountis
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis-Mezourlo, 41500 Larissa, Greece
| | - Zoe Stylianidou
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis-Mezourlo, 41500 Larissa, Greece
| | - Anxhela Zaka
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis-Mezourlo, 41500 Larissa, Greece
| | - Styliani Pappa
- Department of Microbiology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Anna Papa
- Department of Microbiology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | | | - Kostas D. Mathiopoulos
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis-Mezourlo, 41500 Larissa, Greece
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Ecological niche modeling based on ensemble algorithms to predicting current and future potential distribution of African swine fever virus in China. Sci Rep 2022; 12:15614. [PMID: 36114368 PMCID: PMC9481527 DOI: 10.1038/s41598-022-20008-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/07/2022] [Indexed: 11/08/2022] Open
Abstract
African swine fever (ASF) is a tick-borne infectious disease initially described in Shenyang province China in 2018 but is now currently present nationwide. ASF has high infectivity and mortality rates, which often results in transportation and trade bans, and high expenses to prevent and control the, hence causing huge economic losses and a huge negative impact on the Chinese pig farming industry. Ecological niche modeling has long been adopted in the epidemiology of infectious diseases, in particular vector-borne diseases. This study aimed to establish an ecological niche model combined with data from ASF incidence rates in China from August 2018 to December 2021 in order to predict areas for African swine fever virus (ASFV) distribution in China. The model was developed in R software using the biomod2 package and ensemble modeling techniques. Environmental and topographic variables included were mean diurnal range (°C), isothermality, mean temperature of wettest quarter (°C), precipitation seasonality (cv), mean precipitation of warmest quarter(mm), mean precipitation of coldest quarter (mm), normalized difference vegetation index, wind speed (m/s), solar radiation (kJ /day), and elevation/altitude (m). Contribution rates of the variables normalized difference vegetation index, mean temperature of wettest quarter, mean precipitation of coldest quarter, and mean precipitation of warmest quarter were, respectively, 47.61%, 28.85%, 10.85%, and 7.27% (according to CA), which accounted for over 80% of contribution rates related to variables. According to model prediction, most of areas revealed as suitable for ASF distribution are located in the southeast coast or central region of China, wherein environmental conditions are suitable for soft ticks’ survival. In contrast, areas unsuitable for ASFV distribution in China are associated with arid climate and poor vegetation, which are less conducive to soft ticks’ survival, hence to ASFV transmission. In addition, prediction spatial suitability for future ASFV distribution suggests narrower areas for ASFV spread. Thus, the ensemble model designed herein could be used to conceive more efficient prevention and control measure against ASF according to different geographical locations in China.
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Carlson CJ, Albery GF, Merow C, Trisos CH, Zipfel CM, Eskew EA, Olival KJ, Ross N, Bansal S. Climate change increases cross-species viral transmission risk. Nature 2022; 607:555-562. [PMID: 35483403 DOI: 10.1101/2020.01.24.918755] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 04/21/2022] [Indexed: 05/28/2023]
Abstract
At least 10,000 virus species have the ability to infect humans but, at present, the vast majority are circulating silently in wild mammals1,2. However, changes in climate and land use will lead to opportunities for viral sharing among previously geographically isolated species of wildlife3,4. In some cases, this will facilitate zoonotic spillover-a mechanistic link between global environmental change and disease emergence. Here we simulate potential hotspots of future viral sharing, using a phylogeographical model of the mammal-virus network, and projections of geographical range shifts for 3,139 mammal species under climate-change and land-use scenarios for the year 2070. We predict that species will aggregate in new combinations at high elevations, in biodiversity hotspots, and in areas of high human population density in Asia and Africa, causing the cross-species transmission of their associated viruses an estimated 4,000 times. Owing to their unique dispersal ability, bats account for the majority of novel viral sharing and are likely to share viruses along evolutionary pathways that will facilitate future emergence in humans. Notably, we find that this ecological transition may already be underway, and holding warming under 2 °C within the twenty-first century will not reduce future viral sharing. Our findings highlight an urgent need to pair viral surveillance and discovery efforts with biodiversity surveys tracking the range shifts of species, especially in tropical regions that contain the most zoonoses and are experiencing rapid warming.
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Affiliation(s)
- Colin J Carlson
- Department of Biology, Georgetown University, Washington, DC, USA.
- Center for Global Health Science & Security, Georgetown University, Washington, DC, USA.
| | - Gregory F Albery
- Department of Biology, Georgetown University, Washington, DC, USA.
- EcoHealth Alliance, New York, NY, USA.
| | - Cory Merow
- Eversource Energy Center, University of Connecticut, Storrs, CT, USA
| | - Christopher H Trisos
- African Climate and Development Initiative, University of Cape Town, Cape Town, South Africa
| | - Casey M Zipfel
- Department of Biology, Georgetown University, Washington, DC, USA
| | - Evan A Eskew
- EcoHealth Alliance, New York, NY, USA
- Department of Biology, Pacific Lutheran University, Tacoma, WA, USA
| | | | - Noam Ross
- EcoHealth Alliance, New York, NY, USA
| | - Shweta Bansal
- Department of Biology, Georgetown University, Washington, DC, USA
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Tjaden NB, Cheng Y, Beierkuhnlein C, Thomas SM. Chikungunya Beyond the Tropics: Where and When Do We Expect Disease Transmission in Europe? Viruses 2021; 13:v13061024. [PMID: 34072346 PMCID: PMC8226708 DOI: 10.3390/v13061024] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 02/02/2023] Open
Abstract
Chikungunya virus disease (chikungunya) is a mosquito-borne infectious disease reported in at least 50 countries, mostly in the tropics. It has spread around the globe within the last two decades, with local outbreaks in Europe. The vector mosquito Aedes albopictus (Diptera, Culicidae) has already widely established itself in southern Europe and is spreading towards central parts of the continent. Public health authorities and policymakers need to be informed about where and when a chikungunya transmission is likely to take place. Here, we adapted a previously published global ecological niche model (ENM) by including only non-tropical chikungunya occurrence records and selecting bioclimatic variables that can reflect the temperate and sub-tropical conditions in Europe with greater accuracy. Additionally, we applied an epidemiological model to capture the temporal outbreak risk of chikungunya in six selected European cities. Overall, the non-tropical ENM captures all the previous outbreaks in Europe, whereas the global ENM had underestimated the risk. Highly suitable areas are more widespread than previously assumed. They are found in coastal areas of the Mediterranean Sea, in the western part of the Iberian Peninsula, and in Atlantic coastal areas of France. Under a worst-case scenario, even large areas of western Germany and the Benelux states are considered potential areas of transmission. For the six selected European cities, June–September (the 22th–38th week) is the most vulnerable time period, with the maximum continuous duration of a possible transmission period lasting up to 93 days (Ravenna, Italy).
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Affiliation(s)
- Nils Benjamin Tjaden
- Department of Biogeography, University of Bayreuth, D-95447 Bayreuth, Germany; (N.B.T.); (Y.C.); (C.B.)
| | - Yanchao Cheng
- Department of Biogeography, University of Bayreuth, D-95447 Bayreuth, Germany; (N.B.T.); (Y.C.); (C.B.)
| | - Carl Beierkuhnlein
- Department of Biogeography, University of Bayreuth, D-95447 Bayreuth, Germany; (N.B.T.); (Y.C.); (C.B.)
- Bayreuth Center of Ecology and Environmental Research BayCEER, University of Bayreuth, D-95447 Bayreuth, Germany
| | - Stephanie Margarete Thomas
- Department of Biogeography, University of Bayreuth, D-95447 Bayreuth, Germany; (N.B.T.); (Y.C.); (C.B.)
- Bayreuth Center of Ecology and Environmental Research BayCEER, University of Bayreuth, D-95447 Bayreuth, Germany
- Correspondence: ; Tel.: +49-921-55-2307
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7
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Scaramozzino P, Carvelli A, Bruni G, Cappiello G, Censi F, Magliano A, Manna G, Ricci I, Rombolà P, Romiti F, Rosone F, Sala MG, Scicluna MT, Vaglio S, De Liberato C. West Nile and Usutu viruses co-circulation in central Italy: outcomes of the 2018 integrated surveillance. Parasit Vectors 2021; 14:243. [PMID: 33962673 PMCID: PMC8103664 DOI: 10.1186/s13071-021-04736-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 04/21/2021] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND West Nile (WNV) and Usutu (USUV) are emerging vector-borne zoonotic flaviviruses. They are antigenically very similar, sharing the same life cycle with birds as amplification host, Culicidae as vector, and man/horse as dead-end host. They can co-circulate in an overlapping geographic range. In Europe, surveillance plans annually detect several outbreaks. METHODS In Italy, a WNV/USUV surveillance plan is in place through passive and active surveillance. After a 2018 WNV outbreak, a reinforced integrated risk-based surveillance was performed in four municipalities through clinical and serological surveillance in horses, Culicidae catches, and testing on human blood-based products for transfusion. RESULTS Eight WNV cases in eight equine holdings were detected. Twenty-three mosquitoe catches were performed and 2367 specimens of Culex pipiens caught; 17 pools were USUV positive. A total of 8889 human blood donations were tested, and two asymptomatic donors were USUV positive. CONCLUSIONS Different surveillance components simultaneously detected WNV only in horses and USUV only in humans and mosquitoes. While in endemic areas (i.e. northern Italy) entomological surveillance is successfully used as an early detection warning, this method in central Italy seems ineffective. To achieve a high level of sensitivity, the entomological trapping effort should probably exceed a reasonable balance between cost and performance. Besides, WNV/USUV early detection can be addressed by horses and birds. Further research is needed to adapt the surveillance components in different epidemiological contexts.
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Affiliation(s)
- Paola Scaramozzino
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Andrea Carvelli
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy.
| | - Gianpaolo Bruni
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | | | - Francesco Censi
- Azienda Sanitaria Locale di Latina, Via Pier Luigi Nervi, Latina Fiori, 04100, Latina, Italy
| | - Adele Magliano
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Giuseppe Manna
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Ida Ricci
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Pasquale Rombolà
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Federico Romiti
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Francesca Rosone
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Marcello Giovanni Sala
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Maria Teresa Scicluna
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
| | - Stefania Vaglio
- Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, 00185, Roma, Italy
| | - Claudio De Liberato
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova 1411, 00178, Roma, Italy
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Ewing DA, Purse BV, Cobbold CA, White SM. A novel approach for predicting risk of vector-borne disease establishment in marginal temperate environments under climate change: West Nile virus in the UK. J R Soc Interface 2021; 18:20210049. [PMID: 34034529 PMCID: PMC8150030 DOI: 10.1098/rsif.2021.0049] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/27/2021] [Indexed: 12/31/2022] Open
Abstract
Vector-borne diseases (VBDs), such as dengue, Zika, West Nile virus (WNV) and tick-borne encephalitis, account for substantial human morbidity worldwide and have expanded their range into temperate regions in recent decades. Climate change has been proposed as a likely driver of past and future expansion, however, the complex ecology of host and vector populations and their interactions with each other, environmental variables and land-use changes makes understanding the likely impacts of climate change on VBDs challenging. We present an environmentally driven, stage-structured, host-vector mathematical modelling framework to address this challenge. We apply our framework to predict the risk of WNV outbreaks in current and future UK climates. WNV is a mosquito-borne arbovirus which has expanded its range in mainland Europe in recent years. We predict that, while risks will remain low in the coming two to three decades, the risk of WNV outbreaks in the UK will increase with projected temperature rises and outbreaks appear plausible in the latter half of this century. This risk will increase substantially if increased temperatures lead to increases in the length of the mosquito biting season or if European strains show higher replication at lower temperatures than North American strains.
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Affiliation(s)
- David A. Ewing
- UK Centre for Ecology and Hydrology, Benson Lane, Wallingford, Oxfordshire, UK
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
- Biomathematics and Statistics Scotland, James Clerk Maxwell Building, The King’s Buildings, University of Edinburgh, Edinburgh, UK
| | - Bethan V. Purse
- UK Centre for Ecology and Hydrology, Benson Lane, Wallingford, Oxfordshire, UK
| | - Christina A. Cobbold
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
- Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, Glasgow, UK
| | - Steven M. White
- UK Centre for Ecology and Hydrology, Benson Lane, Wallingford, Oxfordshire, UK
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9
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Joshi A, Miller C. Review of machine learning techniques for mosquito control in urban environments. ECOL INFORM 2021. [DOI: 10.1016/j.ecoinf.2021.101241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Bravo-Barriga D, Aguilera-Sepúlveda P, Guerrero-Carvajal F, Llorente F, Reina D, Pérez-Martín JE, Jiménez-Clavero MÁ, Frontera E. West Nile and Usutu virus infections in wild birds admitted to rehabilitation centres in Extremadura, western Spain, 2017-2019. Vet Microbiol 2021; 255:109020. [PMID: 33677369 DOI: 10.1016/j.vetmic.2021.109020] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/22/2021] [Indexed: 12/11/2022]
Abstract
West Nile virus (WNV) is an emerging flavivirus transmitted generally by mosquitoes of Culex genus. It is maintained in an enzootic life cycle where birds act as reservoir hosts. Humans and horses are also susceptible to infection, and occasionally, they suffer from neurological complications. However, they do not transmit the virus to other vectors, behaving as dead-end hosts. Sporadic WNV outbreaks observed in horses and wild birds from Extremadura (western Spain) during 2016 and 2017 seasons prompted to carry out this survey in wild birds, focused on specimens coming from two wildlife rehabilitation centres. Between October 2017 and December 2019, samples from 391 wild birds, belonging to 56 different species were collected and analysed in search of evidence of WNV infection. The analysis of serum samples for WNV-specific antibodies by ELISA, whose specificity was subsequently confirmed by virus-neutralisation test (VNT) showed positive results in 18.23 % birds belonging to 18 different species. Pelecaniformes (33.33 %), Accipitriformes (25.77 %) and Strigiformes (22.92 %) orders had the higher seroprevalences. Remarkably, WNV-specific antibodies were found in a black stork for the first time in Europe. Analysis by real time RT-PCR in symptomatic birds confirmed the presence of WNV lineage 1 RNA in griffon vulture and little owls. Specificity analysis of ELISA positive and doubtful sera was performed by differential VNT titration against WNV and two other cross-reacting avian flaviviruses found in Spain: Usutu virus (USUV) and Bagaza virus (BAGV). Only four samples showed USUV-specific antibodies (1.04 %) corresponding to three species: Eurasian eagle-owl, griffon vulture and great bustard (first detection in Europe) whereas no samples were found reactive to BAGV. Differential VNT yielded undetermined flavivirus result in 16 samples (4.17 %). This is the first study carried out on wild birds from Extremadura (western Spain). It highlights the widespread circulation of WNV in the region and its co-circulation with USUV.
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Affiliation(s)
- Daniel Bravo-Barriga
- Animal Health Department, Veterinary Faculty, University of Extremadura (UEx), Cáceres, Spain.
| | - Pilar Aguilera-Sepúlveda
- Animal Health Research Centre, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Valdeolmos, Madrid, Spain.
| | | | - Francisco Llorente
- Animal Health Research Centre, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Valdeolmos, Madrid, Spain.
| | - David Reina
- Animal Health Department, Veterinary Faculty, University of Extremadura (UEx), Cáceres, Spain.
| | - J Enrique Pérez-Martín
- Animal Health Department, Veterinary Faculty, University of Extremadura (UEx), Cáceres, Spain.
| | - Miguel Ángel Jiménez-Clavero
- Animal Health Research Centre, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Valdeolmos, Madrid, Spain; Centro de Investigación Biomédica en Red de Epidemiologia y Salud Pública (CIBERESP), Madrid, Spain.
| | - Eva Frontera
- Animal Health Department, Veterinary Faculty, University of Extremadura (UEx), Cáceres, Spain.
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Relevance of oxidative stress in inhibition of eIF2 alpha phosphorylation and stress granules formation during Usutu virus infection. PLoS Negl Trop Dis 2021; 15:e0009072. [PMID: 33493202 PMCID: PMC7861526 DOI: 10.1371/journal.pntd.0009072] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 02/04/2021] [Accepted: 12/14/2020] [Indexed: 12/12/2022] Open
Abstract
Usutu virus (USUV) is an African mosquito-borne flavivirus closely related to West Nile, Japanese encephalitis, Zika, and dengue viruses. USUV emerged in 1996 in Europe, where quickly spread across the continent causing a considerable number of bird deaths and varied neurological disorders in humans, including encephalitis, meningoencephalitis, or facial paralysis, thus warning about USUV as a potential health threat. USUV replication takes place on the endoplasmic reticulum (ER) of infected cells, inducing ER stress and resulting in the activation of stress-related cellular pathways collectively known as the integrated stress response (ISR). The alpha subunit of the eukaryotic initiation factor eIF2 (eIF2α), the core factor in this pathway, is phosphorylated by stress activated kinases: protein kinase R (PKR), PKR-like endoplasmic reticulum kinase (PERK), heme-regulated inhibitor kinase (HRI), and general control non-repressed 2 kinase (GCN2). Its phosphorylation results, among others, in the downstream inhibition of translation with accumulation of discrete foci in the cytoplasm termed stress granules (SGs). Our results indicated that USUV infection evades cellular stress response impairing eIF2α phosphorylation and SGs assembly induced by treatment with the HRI activator ArsNa. This protective effect was related with oxidative stress responses in USUV-infected cells. Overall, these results provide new insights into the complex connections between the stress response and flavivirus infection in order to maintain an adequate cellular environment for viral replication. Usutu virus (USUV) infection impairs eIF2α phosphorylation and SGs assembly, in an oxidative stress related manner, as a mechanism to evade cellular stress response. Our results provide new insights into the complex connections between the stress response and USUV infection to maintain a better cellular environment for viral replication.
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12
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Cheng Y, Tjaden NB, Jaeschke A, Thomas SM, Beierkuhnlein C. Deriving risk maps from epidemiological models of vector borne diseases: State-of-the-art and suggestions for best practice. Epidemics 2020; 33:100411. [PMID: 33130413 DOI: 10.1016/j.epidem.2020.100411] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 09/03/2020] [Accepted: 10/01/2020] [Indexed: 11/19/2022] Open
Abstract
Epidemiological models (EMs) are widely used to predict the temporal outbreak risk of vector-borne diseases (VBDs). EMs typically use the basic reproduction number (R0), a threshold quantity, to indicate risk. To provide an overall view of the risk, these model outputs can be transformed into spatial risk maps, using various aggregation methods (e.g. average R0 over time, cumulative number of days with R0 > 1). However, there is no standardized methodology available for this. Depending on the specific aggregation methods used, the yielded spatial risk maps may have considerably different interpretations. Additionally, the method used to visualize the aggregated data also affects the perceived spatial patterns. In this review, we compare commonly used aggregation and visualization methods and discuss the respective interpretation of risk maps. Research publications using epidemiological modelling methods were drawn from Web of Science. Only publications containing maps of R0 transformed from EMs were considered for the analysis. An example EM was applied to illustrate how aggregation and visualization methods affect the final presentations of risk maps. Risk maps can be generated to show duration, intensity and spatio-temporal dynamics of potential outbreak risk of VBDs. We show that 1) different temporal aggregation methods lead to different interpretations; 2) similar spatial patterns do not necessarily bear the same meaning; 3) visualization methods considerably affect how results are perceived, and thus should be applied with caution. We recommend mapping both intensity and duration of the VBD outbreak risk, using small time-steps to show spatio-temporal dynamics when possible.
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Affiliation(s)
- Yanchao Cheng
- Department of Biogeography, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany.
| | - Nils Benjamin Tjaden
- Department of Biogeography, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany
| | - Anja Jaeschke
- Department of Biogeography, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany
| | - Stephanie Margarete Thomas
- Department of Biogeography, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany; BayCEER, Bayreuth Center for Ecology and Environmental Research, Bayreuth, Germany
| | - Carl Beierkuhnlein
- Department of Biogeography, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany; BayCEER, Bayreuth Center for Ecology and Environmental Research, Bayreuth, Germany
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13
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Madzokere ET, Hallgren W, Sahin O, Webster JA, Webb CE, Mackey B, Herrero LJ. Integrating statistical and mechanistic approaches with biotic and environmental variables improves model predictions of the impact of climate and land-use changes on future mosquito-vector abundance, diversity and distributions in Australia. Parasit Vectors 2020; 13:484. [PMID: 32967711 PMCID: PMC7510059 DOI: 10.1186/s13071-020-04360-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 09/11/2020] [Indexed: 02/07/2023] Open
Abstract
Changes to Australia's climate and land-use patterns could result in expanded spatial and temporal distributions of endemic mosquito vectors including Aedes and Culex species that transmit medically important arboviruses. Climate and land-use changes greatly influence the suitability of habitats for mosquitoes and their behaviors such as mating, feeding and oviposition. Changes in these behaviors in turn determine future species-specific mosquito diversity, distribution and abundance. In this review, we discuss climate and land-use change factors that influence shifts in mosquito distribution ranges. We also discuss the predictive and epidemiological merits of incorporating these factors into a novel integrated statistical (SSDM) and mechanistic species distribution modelling (MSDM) framework. One potentially significant merit of integrated modelling is an improvement in the future surveillance and control of medically relevant endemic mosquito vectors such as Aedes vigilax and Culex annulirostris, implicated in the transmission of many arboviruses such as Ross River virus and Barmah Forest virus, and exotic mosquito vectors such as Aedes aegypti and Aedes albopictus. We conducted a focused literature search to explore the merits of integrating SSDMs and MSDMs with biotic and environmental variables to better predict the future range of endemic mosquito vectors. We show that an integrated framework utilising both SSDMs and MSDMs can improve future mosquito-vector species distribution projections in Australia. We recommend consideration of climate and environmental change projections in the process of developing land-use plans as this directly impacts mosquito-vector distribution and larvae abundance. We also urge laboratory, field-based researchers and modellers to combine these modelling approaches. Having many different variations of integrated (SDM) modelling frameworks could help to enhance the management of endemic mosquitoes in Australia. Enhanced mosquito management measures could in turn lead to lower arbovirus spread and disease notification rates.
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Affiliation(s)
- Eugene T. Madzokere
- Institute for Glycomics, Griffith University, Gold Coast Campus, Southport, QLD 4215 Australia
| | - Willow Hallgren
- Environmental Futures Research Institute, Griffith School of Environment, Gold Coast campus, Griffith University, Gold Coast, QLD 4222 Australia
| | - Oz Sahin
- Cities Research Institute, Gold Coast campus, Griffith University, Gold Coast, QLD 4222 Australia
| | - Julie A. Webster
- QIMR Berghofer Medical Research Institute, 300 Herston Road, Herston, QLD 4006 Australia
| | - Cameron E. Webb
- Department of Medical Entomology, NSW Health Pathology, ICPMR, Westmead Hospital, Westmead, NSW 2145 Australia
- Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney, Sydney, NSW 2006 Australia
| | - Brendan Mackey
- Griffith Climate Change Response Program, Griffith School of Environment, Gold Coast campus, Griffith University, Gold Coast, QLD 4222 Australia
| | - Lara J. Herrero
- Institute for Glycomics, Griffith University, Gold Coast Campus, Southport, QLD 4215 Australia
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14
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Caputo B, Manica M. Mosquito surveillance and disease outbreak risk models to inform mosquito-control operations in Europe. CURRENT OPINION IN INSECT SCIENCE 2020; 39:101-108. [PMID: 32403040 DOI: 10.1016/j.cois.2020.03.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 03/09/2020] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
Surveillance programs are needed to guide mosquito-control operations to reduce both nuisance and the spread of mosquito-borne diseases. Understanding the thresholds for action to reduce both nuisance and the risk of arbovirus transmission is becoming critical. To date, mosquito surveillance is mainly implemented to inform about pathogen transmission risks rather than to reduce mosquito nuisance even though lots of control efforts are aimed at the latter. Passive surveillance, such as digital monitoring (validated by entomological trapping), is a powerful tool to record biting rates in real time. High-quality data are essential to model the risk of arbovirus diseases. For invasive pathogens, efforts are needed to predict the arrival of infected hosts linked to the small-scale vector to host contact ratio, while for endemic pathogens efforts are needed to set up region-wide highly structured surveillance measures to understand seasonal re-activation and pathogen transmission in order to carry out effective control operations.
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Affiliation(s)
- Beniamino Caputo
- Department of Public Health and Infectious Diseases, University of Rome La Sapienza, Piazzale A. Moro 5, 38010, 00185 Rome, Italy.
| | - Mattia Manica
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all' Adige, Italy
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15
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Genomic monitoring to understand the emergence and spread of Usutu virus in the Netherlands, 2016-2018. Sci Rep 2020; 10:2798. [PMID: 32071379 PMCID: PMC7029044 DOI: 10.1038/s41598-020-59692-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 01/31/2020] [Indexed: 12/22/2022] Open
Abstract
Usutu virus (USUV) is a mosquito-borne flavivirus circulating in Western Europe that causes die-offs of mainly common blackbirds (Turdus merula). In the Netherlands, USUV was first detected in 2016, when it was identified as the likely cause of an outbreak in birds. In this study, dead blackbirds were collected, screened for the presence of USUV and submitted to Nanopore-based sequencing. Genomic sequences of 112 USUV were obtained and phylogenetic analysis showed that most viruses identified belonged to the USUV Africa 3 lineage, and molecular clock analysis evaluated their most recent common ancestor to 10 to 4 years before first detection of USUV in the Netherlands. USUV Europe 3 lineage, commonly found in Germany, was less frequently detected. This analyses further suggest some extent of circulation of USUV between the Netherlands, Germany and Belgium, as well as likely overwintering of USUV in the Netherlands.
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Hönig V, Palus M, Kaspar T, Zemanova M, Majerova K, Hofmannova L, Papezik P, Sikutova S, Rettich F, Hubalek Z, Rudolf I, Votypka J, Modry D, Ruzek D. Multiple Lineages of Usutu Virus ( Flaviviridae, Flavivirus) in Blackbirds ( Turdus merula) and Mosquitoes ( Culex pipiens, Cx. modestus) in the Czech Republic (2016-2019). Microorganisms 2019; 7:E568. [PMID: 31744087 PMCID: PMC6920817 DOI: 10.3390/microorganisms7110568] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 10/29/2019] [Accepted: 11/15/2019] [Indexed: 01/23/2023] Open
Abstract
Usutu virus (USUV) is a flavivirus (Flaviviridae: Flavivirus) of an African origin transmitted among its natural hosts (diverse species of birds) by mosquitoes. The virus was introduced multiple times to Europe where it caused mortality of blackbirds (Turdus merula) and certain other susceptible species of birds. In this study, we report detection of USUV RNA in blackbirds, Culex pipiens and Cx. modestus mosquitoes in the Czech Republic, and isolation of 10 new Czech USUV strains from carcasses of blackbirds in cell culture. Multiple lineages (Europe 1, 2 and Africa 3) of USUV were found in blackbirds and mosquitoes in the southeastern part of the country. A single USUV lineage (Europe 3) was found in Prague and was likely associated with increased mortalities in the local blackbird population seen in this area in 2018. USUV genomic RNA (lineage Europe 2) was detected in a pool of Cx. pipiens mosquitoes from South Bohemia (southern part of the country), where no major mortality of birds has been reported so far, and no flavivirus RNA has been found in randomly sampled cadavers of blackbirds. The obtained data contributes to our knowledge about USUV genetic variability, distribution and spread in Central Europe.
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Affiliation(s)
- Vaclav Hönig
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
- Department of Virology, Veterinary Research Institute, 62100 Brno, Czech Republic
| | - Martin Palus
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
- Department of Virology, Veterinary Research Institute, 62100 Brno, Czech Republic
| | - Tomas Kaspar
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
- Faculty of Science, University of South Bohemia, 37005 Ceske Budejovice, Czech Republic
| | - Marta Zemanova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
| | - Karolina Majerova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
- Department of Parasitology, Faculty of Science, Charles University, 12800 Prague, Czech Republic
| | - Lada Hofmannova
- Department of Pathology and Parasitology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, 61242 Brno, Czech Republic; (L.H.); (P.P.)
| | - Petr Papezik
- Department of Pathology and Parasitology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, 61242 Brno, Czech Republic; (L.H.); (P.P.)
| | - Silvie Sikutova
- Institute of Vertebrate Biology, Czech Academy of Sciences, 60365 Brno, Czech Republic; (S.S.); (Z.H.); (I.R.)
| | - Frantisek Rettich
- Centre for Epidemiology and Microbiology, National Institute of Public Health, 10000 Prague, Czech Republic;
| | - Zdenek Hubalek
- Institute of Vertebrate Biology, Czech Academy of Sciences, 60365 Brno, Czech Republic; (S.S.); (Z.H.); (I.R.)
| | - Ivo Rudolf
- Institute of Vertebrate Biology, Czech Academy of Sciences, 60365 Brno, Czech Republic; (S.S.); (Z.H.); (I.R.)
| | - Jan Votypka
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
- Department of Parasitology, Faculty of Science, Charles University, 12800 Prague, Czech Republic
| | - David Modry
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
- Department of Pathology and Parasitology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, 61242 Brno, Czech Republic; (L.H.); (P.P.)
- CEITEC, University of Veterinary and Pharmaceutical Sciences, 61242 Brno, Czech Republic
| | - Daniel Ruzek
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic; (M.P.); (T.K.); (M.Z.); (K.M.); (J.V.); (D.M.); (D.R.)
- Department of Virology, Veterinary Research Institute, 62100 Brno, Czech Republic
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17
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Weidinger P, Kolodziejek J, Bakonyi T, Brunthaler R, Erdélyi K, Weissenböck H, Nowotny N. Different dynamics of Usutu virus infections in Austria and Hungary, 2017-2018. Transbound Emerg Dis 2019; 67:298-307. [PMID: 31505099 PMCID: PMC7003936 DOI: 10.1111/tbed.13351] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/23/2019] [Accepted: 08/30/2019] [Indexed: 12/19/2022]
Abstract
Usutu virus (USUV), a mosquito‐borne flavivirus closely related to West Nile virus, emerged in Austria in 2001, when it caused a considerable mass‐mortality of Eurasian blackbirds. Cases in birds increased until 2003 and quickly declined thereafter, presumably due to developing herd immunity. Since 2006, no further cases were recorded, until two blackbirds were tested positive in 2016. In Hungary, USUV first appeared in 2005 and has caused only sporadic infections since then. Initially, the only genetic USUV lineage found across both countries was Europe 1. This changed in 2015/2016, when Europe 2 emerged, which has since then become the prevalent lineage. Due to dispersal of these strains and introduction of new genetic lineages, USUV infections are now widespread across Europe. In 2009, the first cases of USUV‐related encephalitis were described in humans, and the virus has been frequently detected in blood donations since 2016. To monitor USUV infections among the Austrian wild bird population in 2017/2018, 86 samples were investigated by RT‐PCR. In 67 of them, USUV nucleic acid was detected (17 in 2017, 50 in 2018). The majority of succumbed birds were blackbirds, found in Vienna and Lower Austria. However, the virus also spread westwards to Upper Austria and southwards to Styria and Carinthia. In Hungary, 253 wild birds were examined, but only six of them were infected with USUV (five in 2017, one in 2018). Thus, in contrast to the considerable increase in USUV‐associated bird mortality in Austria, the number of infections in Hungary declined after a peak in 2016. Except for one case of USUV lineage Africa 3 in Austria in 2017, Europe 2 remains the most prevalent genetic lineage in both countries. Since USUV transmission largely depends on temperature, which affects vector populations, climate change may cause more frequent USUV outbreaks in the future.
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Affiliation(s)
- Pia Weidinger
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine, Vienna, Austria
| | - Jolanta Kolodziejek
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine, Vienna, Austria
| | - Tamás Bakonyi
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine, Vienna, Austria.,Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | - René Brunthaler
- Institute of Pathology, University of Veterinary Medicine, Vienna, Austria
| | - Károly Erdélyi
- Veterinary Diagnostic Directorate, National Food Chain Safety Office, Budapest, Hungary
| | | | - Norbert Nowotny
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine, Vienna, Austria.,Department of Basic Medical Sciences, College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, United Arab Emirates
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18
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Usutu Virus: An Arbovirus on the Rise. Viruses 2019; 11:v11070640. [PMID: 31336826 PMCID: PMC6669749 DOI: 10.3390/v11070640] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 12/23/2022] Open
Abstract
The Usutu virus (USUV) is a flavivirus that is drawing increasing attention because of its potential for emergence. First isolated in Africa, it was introduced into Europe where it caused significant outbreaks in birds, such as in Austria in 2001. Since then, its geographical distribution has rapidly expanded, with increased circulation, especially in the last few years. Similar to West Nile virus (WNV), the USUV enzootic transmission cycle involves Culex mosquitoes as vectors, and birds as amplifying reservoir hosts, with humans and other mammals likely being dead-end hosts. A similarity in the ecology of these two viruses, which co-circulate in several European countries, highlights USUV’s potential to become an important human pathogen. While USUV has had a severe impact on the blackbird population, the number of human cases remains low, with most infections being asymptomatic. However, some rare cases of neurological disease have been described, both in healthy and immuno-compromised patients. Here, we will discuss the transmission dynamics and the current state of USUV circulation in Europe.
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