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Benn JS, Orange JP, Gomez JP, Dinh ETN, McGregor BL, Blosser EM, Burkett-Cadena ND, Wisely SM, Blackburn JK. Culicoides Midge Abundance across Years: Modeling Inter-Annual Variation for an Avian Feeder and a Candidate Vector of Hemorrhagic Diseases in Farmed Wildlife. Viruses 2024; 16:766. [PMID: 38793647 PMCID: PMC11125994 DOI: 10.3390/v16050766] [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: 01/31/2024] [Revised: 04/25/2024] [Accepted: 05/04/2024] [Indexed: 05/26/2024] Open
Abstract
(1) Background: Epizootic hemorrhagic disease virus (EHDV) and bluetongue virus (BTV) are orbiviruses that cause hemorrhagic disease (HD) with significant economic and population health impacts on domestic livestock and wildlife. In the United States, white-tailed deer (Odocoileus virginianus) are particularly susceptible to these viruses and are a frequent blood meal host for various species of Culicoides biting midges (Diptera: Ceratopogonidae) that transmit orbiviruses. The species of Culicoides that transmit EHDV and BTV vary between regions, and larval habitats can differ widely between vector species. Understanding how midges are distributed across landscapes can inform HD virus transmission risk on a local scale, allowing for improved animal management plans to avoid suspected high-risk areas or target these areas for insecticide control. (2) Methods: We used occupancy modeling to estimate the abundance of gravid (egg-laden) and parous (most likely to transmit the virus) females of two putative vector species, C. stellifer and C. venustus, and one species, C. haematopotus, that was not considered a putative vector. We developed a universal model to determine habitat preferences, then mapped a predicted weekly midge abundance during the HD transmission seasons in 2015 (July-October) and 2016 (May-October) in Florida. (3) Results: We found differences in habitat preferences and spatial distribution between the parous and gravid states for C. haematopotus and C. stellifer. Gravid midges preferred areas close to water on the border of well and poorly drained soil. They also preferred mixed bottomland hardwood habitats, whereas parous midges appeared less selective of habitat. (4) Conclusions: If C. stellifer is confirmed as an EHDV vector in this region, the distinct spatial and abundance patterns between species and physiological states suggest that the HD risk is non-random across the study area.
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Affiliation(s)
- Jamie S. Benn
- Spatial Epidemiology & Ecology Research Laboratory, Department of Geography, University of Florida, 3141 Turlington Hall, Gainesville, FL 32611, USA; (J.S.B.); (J.P.O.)
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL 32611, USA
| | - Jeremy P. Orange
- Spatial Epidemiology & Ecology Research Laboratory, Department of Geography, University of Florida, 3141 Turlington Hall, Gainesville, FL 32611, USA; (J.S.B.); (J.P.O.)
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL 32611, USA
| | - Juan Pablo Gomez
- Departamento de Química y Biología, Universidad del Norte, Barranquilla 080001, Colombia;
| | - Emily T. N. Dinh
- Michigan Department of Health and Human Services, 333 S Grand Ave, Lansing, MI 48933, USA;
| | - Bethany L. McGregor
- USDA-ARS-Center for Grain and Animal Health Research-Arthropod-Borne Animal Diseases Research Unit, 1515 College Ave, Manhatten, KS 66506, USA;
| | - Erik M. Blosser
- Sutter-Yuba Mosquito & Vector Control District, 701 Bogue Road, Yuba City, CA 95991, USA;
| | - Nathan D. Burkett-Cadena
- Florida Medical Entomology Laboratory, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA;
| | - Samantha M. Wisely
- Department of Wildlife Ecology and Conservation, 110 Newins-Ziegler Hall, Gainesville, FL 32611, USA;
| | - Jason K. Blackburn
- Spatial Epidemiology & Ecology Research Laboratory, Department of Geography, University of Florida, 3141 Turlington Hall, Gainesville, FL 32611, USA; (J.S.B.); (J.P.O.)
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL 32611, USA
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Kampen H, Werner D. Biting Midges (Diptera: Ceratopogonidae) as Vectors of Viruses. Microorganisms 2023; 11:2706. [PMID: 38004718 PMCID: PMC10673010 DOI: 10.3390/microorganisms11112706] [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: 08/23/2023] [Revised: 10/30/2023] [Accepted: 11/02/2023] [Indexed: 11/26/2023] Open
Abstract
Biting midges of the genus Culicoides occur almost globally and can regionally and seasonally reach high abundances. Most species are hematophagous, feeding on all groups of vertebrates, including humans. In addition to being nuisance pests, they are able to transmit disease agents, with some viruses causing high morbidity and/or mortality in ruminants, horses and humans. Despite their impact on animal husbandry, public health and tourism, knowledge on the biology and ecology of culicoid biting midges and their interactions with ingested pathogens or symbiotic microorganisms is limited. Research is challenging due to unknown larval habitats, the insects' tiny size, the inability to establish and breed most species in the laboratory and the laborious maintenance of colonies of the few species that can be reared in the laboratory. Consequently, the natural transmission of pathogens has experimentally been demonstrated for few species while, for others, only indirect evidence of vector potential exists. Most experimental data are available for Culicoides sonorensis and C. nubeculosus, the only species kept in western-world insectaries. This contribution gives an overview on important biting midge vectors, transmitted viruses, culicoid-borne viral diseases and their epidemiologies and summarizes the little knowledge on interactions between biting midges, their microflora and culicoid-borne arboviruses.
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Affiliation(s)
- Helge Kampen
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, 17493 Greifswald, Germany
| | - Doreen Werner
- Leibniz Centre for Agricultural Landscape Research, 15374 Muencheberg, Germany;
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Venter GJ, Sebitsang SS, Swart VR, Boikanyo SNB, de Beer CJ. Comparison of the efficiency of the Onderstepoort- and Centres for Disease Control ultraviolet light traps for the collection of livestock associated Culicoides species in South Africa. MEDICAL AND VETERINARY ENTOMOLOGY 2022; 36:113-126. [PMID: 34811772 DOI: 10.1111/mve.12558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 09/11/2021] [Accepted: 10/29/2021] [Indexed: 06/13/2023]
Abstract
Comparative monitoring of the abundance and distribution of Culicoides biting midges (Diptera: Ceratopogonidae), the biological vectors of the causative agents of several diseases of global veterinary importance, will be crucial in determining the risk of disease outbreak and spread. Ultraviolet (UV) suction traps have become the most frequent method used for the monitoring of Culicoides diversity and abundance. The current study compared the trapping efficiency of the two most used UV suction light traps, i.e., the Onderstepoort (OP)- and the Centres for Disease Control trap, for the collection of livestock associated Culicoides species in South Africa. The study confirmed the superiority of the OP trap and indicated a correlation in species composition and age grading results as determine with the two trap types. Substantial variations in the comparative trap efficiency, as found between areas and sites within an area, suggest that a universal conversion factor between the two trap types may not be advisable as it is unclear to what extent species composition and environmental factors may influence the conversion factor. Light traps, independent of trap model, can be considered acceptable for determining the serial comparison of population numbers for seasonal fluctuation and species abundance in distribution surveys.
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Affiliation(s)
- G J Venter
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
- Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
| | - S S Sebitsang
- Department of Zoology and Entomology, University of the Free State, Bloemfontein, South Africa
- Department of Research Operations, Clinvet International (Pty) Ltd., Bloemfontein, South Africa
| | - V R Swart
- Department of Zoology and Entomology, University of the Free State, Bloemfontein, South Africa
| | - S N B Boikanyo
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
| | - C J de Beer
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
- Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Insect Pest Control Laboratory, Vienna, Austria
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The Absence of Abdominal Pigmentation in Livestock Associated Culicoides following Artificial Blood Feeding and the Epidemiological Implication for Arbovirus Surveillance. Pathogens 2021; 10:pathogens10121571. [PMID: 34959526 PMCID: PMC8705276 DOI: 10.3390/pathogens10121571] [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: 10/30/2021] [Revised: 11/25/2021] [Accepted: 11/29/2021] [Indexed: 12/02/2022] Open
Abstract
Culicoides midges (Diptera: Ceratopogonidae), the vectors of economically important arboviruses such as bluetongue virus and African horse sickness virus, are of global importance. In the absence of transovarial transmission, the parity rate of a Culicoides population provides imperative information regarding the risk of virus dispersal. Abdominal pigmentation, which develops after blood feeding and ovipositioning, is used as an indicator of parity in Culicoides. During oral susceptibility trials over the last three decades, a persistent proportion of blood engorged females did not develop pigment after incubation. The present study, combining a number of feeding trials and different artificial feeding methods, reports on this phenomenon, as observed in various South African and Italian Culicoides species and populations. The absence of pigmentation in artificial blood-fed females was found in at least 23 Culicoides species, including important vectors such as C. imicola, C. bolitinos, C. obsoletus, and C. scoticus. Viruses were repeatedly detected in these unpigmented females after incubation. Blood meal size seems to play a role and this phenomenon could be present in the field and requires consideration, especially regarding the detection of virus in apparent “nulliparous” females and the identification of overwintering mechanisms and seasonally free vector zones.
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Korkmaz C, Alten B, Erol U, Deniz A. Updated checklist of Culicoides Latreille (Diptera: Ceratopogonidae) of Turkey with ten new records. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2021; 46:124-136. [PMID: 35230016 DOI: 10.52707/1081-1710-46.2.124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/24/2021] [Indexed: 06/14/2023]
Abstract
We investigated the Culicoides fauna in Turkey during the years 2016-2019 in the process of entomological surveillance for arboviral diseases. The entomological survey was conducted at 104 sampling stations in 51 provinces in Turkey during four consecutive years. There were approximately 450,000 specimens and 59 identified species collected during the surveillance. Ten species were newly recorded for Turkey: C. chiopterus, C. grisescens, C. paradoxalis, C. santonicus, C. poperinghensis, C. sergenti, C. tbilisicus, C. comosioculatus, C. haranti, and C. univittatus. Identification of C. chiopterus and C. grisescens was confirmed using species-specific PCR and DNA sequencing. With our recent findings, previous data were critically reviewed and updated, and the number of Culicoides species has been increased to 71 for Turkey. The presence of C. chiopterus has particular importance due to its potential vector status for bluetongue virus (BTV) and Schmallenberg virus (SBV). This study presents result of the first large-scale integrated faunistic survey on Culicoides species in Turkey.
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Affiliation(s)
- Cagla Korkmaz
- Veterinary Control Central Research Institute, Ankara, Turkey,
- Hacettepe University, Graduate School of Science and Engineering, Ankara, Turkey
| | - Bulent Alten
- Hacettepe University, Faculty of Science, Department of Biology, Ecology Division, VERG laboratories, Beytepe, Ankara, Turkey
| | - Ufuk Erol
- Sivas Cumhuriyet University, Faculty of Veterinary Medicine, Department of Parasitology, Sivas, Turkey
| | - Ahmet Deniz
- Veterinary Control Central Research Institute, Ankara, Turkey
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Ramilo DW, Filipe AM, Lucientes J, Rebelo MT, Cardoso L, da Fonseca IP. Morphological anomalies found in female Culicoides midges (Diptera: Ceratopogonidae). Biologia (Bratisl) 2021. [DOI: 10.1007/s11756-021-00822-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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de Beer CJ, Boikanyo SNB, Venter GJ. Evaluation of light emitting diode suction traps for the collection of livestock-associated Culicoides species in South Africa. MEDICAL AND VETERINARY ENTOMOLOGY 2021; 35:408-416. [PMID: 33577119 DOI: 10.1111/mve.12512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/01/2020] [Accepted: 01/12/2021] [Indexed: 06/12/2023]
Abstract
Risk analysis of pathogens transmitted by Culicoides (Diptera; Ceratopogonidae) depends on the ability to detect all potential vectors attacking livestock in an area. Onderstepoort 220-V ultraviolet (UV) down-draught light traps are considered the gold standard for this purpose. To improve the flexibility of this trap in the field, in the absence of 220-V power, the possibility of using low-energy light emitting diodes (LEDs) was assessed. The efficiency of a standard 220-V Onderstepoort trap (30 cm 8 W fluorescent UV light tube) was compared to that of 220-V Onderstepoort traps fitted with either two, four or eight individual white LEDs. The Onderstepoort 220-V trap was also compared to a 12-V Onderstepoort trap fitted with an 8 W fluorescent UV light tube, a 12-V Onderstepoort trap with 12 individual white LEDs and 12-V and 220-V Onderstepoort traps fitted with 12 individual UV LEDs. Higher numbers of Culicoides as well as species diversity were collected with a brighter light source. The use of UV LEDs in both the 12-V and 220-V combinations was comparable to the Onderstepoort 220-V light trap with ration to species diversity collected. The Onderstepoort 220-V light trap is recommended if large numbers of Culicoides need to be collected.
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Affiliation(s)
- C J de Beer
- Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Insect Pest Control Laboratory, Vienna, Austria
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
| | - S N B Boikanyo
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
| | - G J Venter
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
- Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
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Aguilar-Vega C, Rivera B, Lucientes J, Gutiérrez-Boada I, Sánchez-Vizcaíno JM. A study of the composition of the Obsoletus complex and genetic diversity of Culicoides obsoletus populations in Spain. Parasit Vectors 2021; 14:351. [PMID: 34217330 PMCID: PMC8254917 DOI: 10.1186/s13071-021-04841-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 06/11/2021] [Indexed: 11/10/2022] Open
Abstract
Background The Culicoides obsoletus species complex (henceforth ‘Obsoletus complex’) is implicated in the transmission of several arboviruses that can cause severe disease in livestock, such as bluetongue, African horse sickness, epizootic hemorrhagic disease and Schmallenberg disease. Thus, this study aimed to increase our knowledge of the composition and genetic diversity of the Obsoletus complex by partial sequencing of the cytochrome c oxidase I (cox1) gene in poorly studied areas of Spain. Methods A study of C. obsoletus populations was carried out using a single-tube multiplex polymerase chain reaction (PCR) assay that was designed to differentiate the Obsoletus complex sibling species Culicoides obsoletus and Culicoides scoticus, based on the partial amplification of the cox1 gene, as well as cox1 georeferenced sequences from Spain available at GenBank. We sampled 117 insects of the Obsoletus complex from six locations and used a total of 238 sequences of C. obsoletus (ss) individuals (sampled here, and from GenBank) from 14 sites in mainland Spain, the Balearic Islands and the Canary Islands for genetic diversity and phylogenetic analyses. Results We identified 90 C. obsoletus (ss), 19 Culicoides scoticus and five Culicoides montanus midges from the six collection sites sampled, and found that the genetic diversity of C. obsoletus (ss) were higher in mainland Spain than in the Canary Islands. The multiplex PCR had limitations in terms of specificity, and no cryptic species within the Obsoletus complex were identified. Conclusions Within the Obsoletus complex, C. obsoletus (ss) was the predominant species in the analyzed sites of mainland Spain. Information about the species composition of the Obsoletus complex could be of relevance for future epidemiological studies when specific aspects of the vector competence and capacity of each species have been identified. Our results indicate that the intraspecific divergence is higher in C. obsoletus (ss) northern populations, and demonstrate the isolation of C. obsoletus (ss) populations of the Canary Islands. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-04841-z.
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Affiliation(s)
- Cecilia Aguilar-Vega
- Animal Health Department, Faculty of Veterinary Medicine, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain.
| | - Belén Rivera
- Animal Health Department, Faculty of Veterinary Medicine, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
| | - Javier Lucientes
- Department of Animal Pathology (Animal Health), Faculty of Veterinary Medicine, AgriFood Institute of Aragón IA2, University of Zaragoza, Zaragoza, Spain
| | - Isabel Gutiérrez-Boada
- Animal Health Department, Faculty of Veterinary Medicine, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
| | - José Manuel Sánchez-Vizcaíno
- Animal Health Department, Faculty of Veterinary Medicine, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
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Van den Eynde C, Sohier C, Matthijs S, De Regge N. Temperature and food sources influence subadult development and blood-feeding response of Culicoides obsoletus (sensu lato) under laboratory conditions. Parasit Vectors 2021; 14:300. [PMID: 34090481 PMCID: PMC8180032 DOI: 10.1186/s13071-021-04781-8] [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: 01/28/2021] [Accepted: 05/11/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Culicoides obsoletus (s.l.) is the most abundant Culicoides species in northern Europe and an important vector of bluetongue virus and Schmallenberg virus. Nevertheless, information on its subadult life stages remains scarce and no laboratory-reared colony exists. METHODS C. obsoletus (s.l.) adults were collected in Belgium and transferred to the laboratory in an attempt to establish a laboratory-reared colony. C. obsoletus (s.l.) were reared from eggs to adults at different temperatures (28 °C, 24 °C, 20/16 °C) and under different food regimes. RESULTS The most suitable temperature for rearing seemed to be 24 °C for most developmental parameters, but resulted in a biased 3:1 male/female sex ratio. The latter could be optimized to a 1:1 sex ratio when a 20/16 °C day/night temperature gradient was applied, but rearing at these low temperature conditions resulted in significantly lower egg hatching and pupation rates and a longer subadult development time. Independent of the rearing temperature, adding dung as an additional food source during larval development resulted in a significantly higher adult emergence rate and a decrease in subadult development time. Furthermore, blood-feeding rates of field-collected C. obsoletus (s.l.) were compared for different blood sources and feeding systems. The overall blood-feeding success was low and only successful with cotton pledgets (2.7% blood-fed midges) and through a membrane system with chicken skin (3.5% blood-fed midges). Higher feeding rates were obtained on cattle blood compared to sheep blood. CONCLUSIONS These results will help us to determine the necessary conditions to rear a viable laboratory colony of this important vector species, although further optimization is still required.
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Affiliation(s)
- Claudia Van den Eynde
- Sciensano, Enzootic, Vector-Borne and Bee Diseases, Groeselenberg 99, 1180, Brussels, Belgium.
| | - Charlotte Sohier
- Sciensano, Enzootic, Vector-Borne and Bee Diseases, Groeselenberg 99, 1180, Brussels, Belgium
| | - Severine Matthijs
- Sciensano, Enzootic, Vector-Borne and Bee Diseases, Groeselenberg 99, 1180, Brussels, Belgium
| | - Nick De Regge
- Sciensano, Enzootic, Vector-Borne and Bee Diseases, Groeselenberg 99, 1180, Brussels, Belgium
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de Beer CJ, Boikanyo SNB, Venter GJ. Assessment of the Hemotek® system for the in vitro feeding of field-collected Culicoides imicola (Diptera: Ceratopogonidae) in South Africa. MEDICAL AND VETERINARY ENTOMOLOGY 2021; 35:177-186. [PMID: 32990991 DOI: 10.1111/mve.12484] [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: 05/07/2020] [Revised: 08/27/2020] [Accepted: 09/04/2020] [Indexed: 06/11/2023]
Abstract
The optimising and standardisation of in vitro blood feeding protocols for field-collected Culicoides species (Diptera: Ceratopogonidae) will be of essence for the comparison of the vector competencies of various populations of viruses of veterinary importance and the establishment of laboratory colonies of putative vector species. A custom-made feeding chamber to accommodate the small size of Culicoides imicola Kieffer was designed for the commercially available Hemotek® system and compared to existing membrane and cotton pledge feeding methods. High feeding rates coupled to higher mean blood meal volume than that of the existing OVI device indicated that the Hemotek system will be suitable for the feeding of field-collected Culicoides. The Hemotek system was subsequently used to identify factors that may affect feeding success in the laboratory. Evaluated factors were the source (host) and temperature of the blood meal, time of the day of feeding, the position of the blood reservoir in relation to the midges and exposure time to the blood. While only feeding orientation and the temperature of the blood source seems to significantly affect the feeding rate, all the factors did influence the volume of blood consumed.
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Affiliation(s)
- C J de Beer
- Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Insect Pest Control Laboratory, Vienna, Austria
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
| | - S N B Boikanyo
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
| | - G J Venter
- Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
- Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
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Barceló C, Purse BV, Estrada R, Lucientes J, Miranda MÁ, Searle KR. Environmental Drivers of Adult Seasonality and Abundance of Biting Midges Culicoides (Diptera: Ceratopogonidae), Bluetongue Vector Species in Spain. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:350-364. [PMID: 32885822 DOI: 10.1093/jme/tjaa160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Indexed: 06/11/2023]
Abstract
Bluetongue is a viral disease affecting wild and domestic ruminants transmitted by several species of biting midges Culicoides Latreille. The phenology of these insects were analyzed in relation to potential environmental drivers. Data from 329 sites in Spain were analyzed using Bayesian Generalized Linear Mixed Model (GLMM) approaches. The effects of environmental factors on adult female seasonality were contrasted. Obsoletus complex species (Diptera: Ceratopogonidae) were the most prevalent across sites, followed by Culicoides newsteadi Austen (Diptera: Ceratopogonidae). Activity of female Obsoletus complex species was longest in sites at low elevation, with warmer spring average temperatures and precipitation, as well as in sites with high abundance of cattle. The length of the Culicoides imicola Kieffer (Diptera: Ceratopogonidae) female adult season was also longest in sites at low elevation with higher coverage of broad-leaved vegetation. Long adult seasons of C. newsteadi were found in sites with warmer autumns and higher precipitation, high abundance of sheep. Culicoides pulicaris (Linnaeus) (Diptera: Ceratopogonidae) had longer adult periods in sites with a greater number of accumulated degree days over 10°C during winter. These results demonstrate the eco-climatic and seasonal differences among these four taxa in Spain, which may contribute to determining sites with suitable environmental circumstances for each particular species to inform assessments of the risk of Bluetongue virus outbreaks in this region.
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Affiliation(s)
- Carlos Barceló
- Applied Zoology and Animal Conservation Research Group, Department of Biology, University of the Balearic Islands (UIB), Ctra. Valldemossa Km 7.5, Palma de Mallorca, Spain
| | - Bethan V Purse
- Centre for Ecology and Hydrology, Oxfordshire, United Kingdom
| | - Rosa Estrada
- Department of Animal Pathology, Faculty of Veterinary, University of Zaragoza, Zaragoza, Spain
| | - Javier Lucientes
- Department of Animal Pathology, Faculty of Veterinary, University of Zaragoza, Zaragoza, Spain
| | - Miguel Á Miranda
- Applied Zoology and Animal Conservation Research Group, Department of Biology, University of the Balearic Islands (UIB), Ctra. Valldemossa Km 7.5, Palma de Mallorca, Spain
| | - Kate R Searle
- Centre for Ecology and Hydrology, Bush Estate, Edinburgh, Scotland
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VectorNet Data Series 3: Culicoides Abundance Distribution Models for Europe and Surrounding Regions. OPEN HEALTH DATA 2020. [DOI: 10.5334/ohd.33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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13
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Belkharchouche M, Berchi S, Mathieu B, Rakotoarivony I, Duhayon M, Baldet T, Balenghien T. Update of the Culicoides (Diptera: Ceratopogonidae) species checklist from Algeria with 10 new records. Parasit Vectors 2020; 13:463. [PMID: 32912306 PMCID: PMC7488159 DOI: 10.1186/s13071-020-04335-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/01/2020] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND The Culicoides fauna of Algeria has been historically investigated, leading to the description of many new species by Kieffer in the 1920s, Clastrier in the 1950s or Callot in the 1960s and to a comprehensive inventory by Szadziewski in the 1980s. The emergence of bluetongue in the late 1990s enhanced Culicoides collections made in the country over the last two decades, but information remained mostly unpublished. The aim of this study is therefore to provide a comprehensive and updated checklist of Culicoides biting midge species in Algeria. METHODS The literature (published and grey, in French and in English) from 1920 to date on Culicoides collections in Algeria was collected and analyzed in the light of the current taxonomic and systematic knowledge and methods. Fresh Culicoides material was also analyzed using light/suction trap collections carried out from November 2015 to September 2018 in nine localities of the 'wilayah' of Tiaret (northwestern Algeria). Slide mounted specimens were identified morphologically using the interactive identification key IIKC and original descriptions. Specimens were then compared with non-type material originating from different countries and partly with type material. RESULTS A total of 13,709 Culicoides, belonging to at least 36 species within 10 subgenera, were examined leading to 10 new records in Algeria, including C. chiopterus, C. dewulfi, C. navaiae, C. grisescens, C. paradoxalis, C. shaklawensis, C. simulator, C. univittatus, C. achrayi and C. picturatus. These new records and all previous records provided by the literature review were discussed. CONCLUSIONS We propose a Culicoides checklist for the Algerian fauna of 59 valid species, including species mainly with a large Palaearctic distribution and a specific Mediterranean distribution, and only a few species from the Afrotropical region. Among them, several species, mainly of the subgenera Avaritia and Culicoides, are confirmed or probable vectors of arboviruses important in animal health.
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Affiliation(s)
- Mounira Belkharchouche
- Ecole Nationale Supérieure de Biotechnologie, Taoufik Khaznadar, nouveau pôle universitaire Ali Mendjeli, B.P. E66, 25100 Constantine, Algérie
- Faculté des Sciences de la Nature et de la Vie, Université Ibn Khaldoun, B.P.75 Zaaroura, Tiaret, 1400 Algérie
- Laboratoire de Biosystématique et Ecologie des Arthropodes, Faculté des Sciences de la Nature et de la Vie, Département de Biologie Animale, Université Frères Mentouri, Constantine 1, 2500 Algérie
- CIRAD, UMR ASTRE, 34398 Montpellier, France
| | - Selima Berchi
- Laboratoire de Biosystématique et Ecologie des Arthropodes, Faculté des Sciences de la Nature et de la Vie, Département de Biologie Animale, Université Frères Mentouri, Constantine 1, 2500 Algérie
| | - Bruno Mathieu
- Institut de Parasitologie et de Pathologies Tropicales de Strasbourg (IPPTS), UR 7292, 3 Rue Koeberlé, 67000 Strasbourg, France
| | - Ignace Rakotoarivony
- CIRAD, UMR ASTRE, 34398 Montpellier, France
- ASTRE, University of Montpellier, CIRAD, INRAE, Montpellier, France
| | - Maxime Duhayon
- CIRAD, UMR ASTRE, 34398 Montpellier, France
- ASTRE, University of Montpellier, CIRAD, INRAE, Montpellier, France
| | - Thierry Baldet
- ASTRE, University of Montpellier, CIRAD, INRAE, Montpellier, France
- CIRAD, UMR ASTRE, 97491 Sainte-Clotilde, La Réunion France
| | - Thomas Balenghien
- ASTRE, University of Montpellier, CIRAD, INRAE, Montpellier, France
- CIRAD, UMR ASTRE, 10101 Rabat, Morocco
- Institut Agronomique et Vétérinaire Hassan II, Unité Microbiologie, Immunologie et Maladies Contagieuses, 10100 Rabat, Morocco
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14
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Halasa T, Græsbøll K, Denwood M, Christensen LE, Kirkeby C. Prediction Models in Veterinary and Human Epidemiology: Our Experience With Modeling Sars-CoV-2 Spread. Front Vet Sci 2020; 7:513. [PMID: 33062646 PMCID: PMC7477293 DOI: 10.3389/fvets.2020.00513] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 07/06/2020] [Indexed: 01/09/2023] Open
Abstract
The worldwide outbreak of Sars-CoV-2 resulted in modelers from diverse fields being called upon to help predict the spread of the disease, resulting in many new collaborations between different institutions. We here present our experience with bringing our skills as veterinary disease modelers to bear on the field of human epidemiology, building models as tools for decision makers, and bridging the gap between the medical and veterinary fields. We describe and compare the key steps taken in modeling the Sars-CoV-2 outbreak: criteria for model choices, model structure, contact structure between individuals, transmission parameters, data availability, model validation, and disease management. Finally, we address how to improve on the contingency infrastructure available for Sars-CoV-2.
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Affiliation(s)
- Tariq Halasa
- Section for Animal Welfare and Disease Control, Institute of Veterinary and Animal Sciences, Faculty of Medical and Health Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Kaare Græsbøll
- Department of Applied Mathematics and Computer Sciences, Technical University of Denmark, Lyngby, Denmark
| | - Matthew Denwood
- Section for Animal Welfare and Disease Control, Institute of Veterinary and Animal Sciences, Faculty of Medical and Health Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Lasse Engbo Christensen
- Department of Applied Mathematics and Computer Sciences, Technical University of Denmark, Lyngby, Denmark
| | - Carsten Kirkeby
- Section for Animal Welfare and Disease Control, Institute of Veterinary and Animal Sciences, Faculty of Medical and Health Sciences, University of Copenhagen, Frederiksberg, Denmark
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15
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Veronesi E, Darpel K, Gubbins S, Batten C, Nomikou K, Mertens P, Carpenter S. Diversity of Transmission Outcomes Following Co-Infection of Sheep with Strains of Bluetongue Virus Serotype 1 and 8. Microorganisms 2020; 8:microorganisms8060851. [PMID: 32516979 PMCID: PMC7356686 DOI: 10.3390/microorganisms8060851] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/31/2020] [Accepted: 06/02/2020] [Indexed: 01/03/2023] Open
Abstract
Bluetongue virus (BTV) causes an economically important disease, bluetongue (BT), in susceptible ruminants and is transmitted primarily by species of Culicoides biting midges (Diptera: Ceratopogonidae). Since 2006, northern Europe has experienced multiple incursions of BTV through a variety of routes of entry, including major outbreaks of strains of BTV serotype 8 (BTV-8) and BTV serotype 1 (BTV-1), which overlapped in distribution within southern Europe. In this paper, we examined the variation in response to coinfection with strains of BTV-1 and BTV-8 using an in vivo transmission model involving Culicoides sonorensis, low passage virus strains, and sheep sourced in the United Kingdom. In the study, four sheep were simultaneously infected using BTV-8 and BTV-1 intrathoracically inoculated C. sonorensis and co-infections of all sheep with both strains were established. However, there were significant variations in both the initiation and peak levels of virus RNA detected throughout the experiment, as well as in the infection rates in the C. sonorensis that were blood-fed on experimentally infected sheep at peak viremia. This is discussed in relation to the potential for reassortment between these strains in the field and the policy implications for detection of BTV strains.
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Affiliation(s)
- Eva Veronesi
- The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK; (K.D.); (S.G.); (C.B.); (K.N.); (P.M.)
- National Centre for Vector Entomology, Institute of Parasitology, Vetsuisse Faculty, 8057 Zurich, Switzerland
- Correspondence: (E.V.); (S.C.)
| | - Karin Darpel
- The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK; (K.D.); (S.G.); (C.B.); (K.N.); (P.M.)
| | - Simon Gubbins
- The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK; (K.D.); (S.G.); (C.B.); (K.N.); (P.M.)
| | - Carrie Batten
- The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK; (K.D.); (S.G.); (C.B.); (K.N.); (P.M.)
| | - Kyriaki Nomikou
- The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK; (K.D.); (S.G.); (C.B.); (K.N.); (P.M.)
- University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD, UK
| | - Peter Mertens
- The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK; (K.D.); (S.G.); (C.B.); (K.N.); (P.M.)
- University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD, UK
| | - Simon Carpenter
- The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK; (K.D.); (S.G.); (C.B.); (K.N.); (P.M.)
- Correspondence: (E.V.); (S.C.)
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16
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Mignotte A, Garros C, Gardès L, Balenghien T, Duhayon M, Rakotoarivony I, Tabourin L, Poujol L, Mathieu B, Ibañez-Justicia A, Deniz A, Cvetkovikj A, Purse BV, Ramilo DW, Stougiou D, Werner D, Pudar D, Petrić D, Veronesi E, Jacobs F, Kampen H, Pereira da Fonseca I, Lucientes J, Navarro J, de la Puente JM, Stefanovska J, Searle KR, Khallaayoune K, Culverwell CL, Larska M, Bourquia M, Goffredo M, Bisia M, England M, Robin M, Quaglia M, Miranda-Chueca MÁ, Bødker R, Estrada-Peña R, Carpenter S, Tchakarova S, Boutsini S, Sviland S, Schäfer SM, Ozoliņa Z, Segliņa Z, Vatansever Z, Huber K. The tree that hides the forest: cryptic diversity and phylogenetic relationships in the Palaearctic vector Obsoletus/Scoticus Complex (Diptera: Ceratopogonidae) at the European level. Parasit Vectors 2020; 13:265. [PMID: 32434592 PMCID: PMC7238629 DOI: 10.1186/s13071-020-04114-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 04/29/2020] [Indexed: 11/27/2022] Open
Abstract
Background Culicoides obsoletus is an abundant and widely distributed Holarctic biting midge species, involved in the transmission of bluetongue virus (BTV) and Schmallenberg virus (SBV) to wild and domestic ruminants. Females of this vector species are often reported jointly with two morphologically very close species, C. scoticus and C. montanus, forming the Obsoletus/Scoticus Complex. Recently, cryptic diversity within C. obsoletus was reported in geographically distant sites. Clear delineation of species and characterization of genetic variability is mandatory to revise their taxonomic status and assess the vector role of each taxonomic entity. Our objectives were to characterize and map the cryptic diversity within the Obsoletus/Scoticus Complex. Methods Portion of the cox1 mitochondrial gene of 3763 individuals belonging to the Obsoletus/Scoticus Complex was sequenced. Populations from 20 countries along a Palaearctic Mediterranean transect covering Scandinavia to Canary islands (North to South) and Canary islands to Turkey (West to East) were included. Genetic diversity based on cox1 barcoding was supported by 16S rDNA mitochondrial gene sequences and a gene coding for ribosomal 28S rDNA. Species delimitation using a multi-marker methodology was used to revise the current taxonomic scheme of the Obsoletus/Scoticus Complex. Results Our analysis showed the existence of three phylogenetic clades (C. obsoletus clade O2, C. obsoletus clade dark and one not yet named and identified) within C. obsoletus. These analyses also revealed two intra-specific clades within C. scoticus and raised questions about the taxonomic status of C. montanus. Conclusions To our knowledge, our study provides the first genetic characterization of the Obsoletus/Scoticus Complex on a large geographical scale and allows a revision of the current taxonomic classification for an important group of vector species of livestock viruses in the Palaearctic region.![]()
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Affiliation(s)
- Antoine Mignotte
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France. .,Cirad, UMR ASTRE, 34398, Montpellier, France.
| | - Claire Garros
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France. .,Cirad, UMR ASTRE, 34398, Montpellier, France.
| | - Laetitia Gardès
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France.,Cirad, UMR ASTRE, 97170, Petit-Bourg, Guadeloupe, France
| | - Thomas Balenghien
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France.,Institut Agronomique et Vétérinaire Hassan II, Unité Parasitologie et Maladies Parasitaires, 10100, Rabat, Morocco
| | - Maxime Duhayon
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France
| | - Ignace Rakotoarivony
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France
| | - Laura Tabourin
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France
| | - Léa Poujol
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France
| | - Bruno Mathieu
- Institute of Parasitology and Tropical Pathology of Strasbourg, Université de Strasbourg, DIHP UR 7292, 67000, Strasbourg, France
| | - Adolfo Ibañez-Justicia
- Centre for Monitoring of Vectors, National Reference Centre, Netherlands Food and Consumer Product Safety Authority, Wageningen, The Netherlands
| | - Ahmet Deniz
- Veterinary Control Central Research Institute, Ankara, Turkey
| | - Aleksandar Cvetkovikj
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Ss. Cyril and Methodius University in Skopje, Skopje, Republic of North Macedonia
| | - Bethan V Purse
- Centre for Ecology, Centre for Ecology & Hydrology, Wallingford, OX10 8BB, UK
| | - David W Ramilo
- CIISA-Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477, Lisboa, Portugal
| | - Despoina Stougiou
- Department of Parasitology-Parasitic Diseases, Entomology & Bee Health, Veterinary Centre of Athens, Athens, Greece
| | - Doreen Werner
- Leibniz-Centre for Agricultural Landscape Research, Müncheberg, Germany
| | - Dubravka Pudar
- Faculty of Agriculture, University of Novi Sad, Novi Sad, Serbia
| | - Dušan Petrić
- Faculty of Agriculture, University of Novi Sad, Novi Sad, Serbia
| | - Eva Veronesi
- National Centre for Vector Entomology, Institute of Parasitology, University of Zürich, Zürich, Switzerland
| | - Frans Jacobs
- Centre for Monitoring of Vectors, National Reference Centre, Netherlands Food and Consumer Product Safety Authority, Wageningen, The Netherlands
| | - Helge Kampen
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Germany
| | - Isabel Pereira da Fonseca
- CIISA-Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477, Lisboa, Portugal
| | - Javier Lucientes
- Department of Animal Pathology, AgriFood Institute of Aragón (IA2) Veterinary Faculty, 50013, Zaragoza, Spain
| | - Javier Navarro
- Departamento de Microbiología, Laboratorio de Producción y Sanidad Animal de Granada, Junta de Andalucía, Granada, Spain
| | - Josue Martinez de la Puente
- Doñana Biological Station, CSIC, Sevilla, Spain.,Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Jovana Stefanovska
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Ss. Cyril and Methodius University in Skopje, Skopje, Republic of North Macedonia
| | - Kate R Searle
- Centre for Ecology & Hydrology, Edinburgh, OX10 8BB, UK
| | - Khalid Khallaayoune
- Institut Agronomique et Vétérinaire Hassan II, Unité Parasitologie et Maladies Parasitaires, 10100, Rabat, Morocco
| | - C Lorna Culverwell
- Department of Virology, University of Helsinki, Medicum, Haartmaninkatu 3, Helsinki, 00014, Finland
| | | | - Maria Bourquia
- Cirad, UMR ASTRE, 34398, Montpellier, France.,Institut Agronomique et Vétérinaire Hassan II, Unité Parasitologie et Maladies Parasitaires, 10100, Rabat, Morocco
| | - Maria Goffredo
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Campo Boario, 64100, Teramo, Italy
| | - Marina Bisia
- Department of Parasitology-Parasitic Diseases, Entomology & Bee Health, Veterinary Centre of Athens, Athens, Greece
| | | | - Matthew Robin
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst, Chester High Road, Neston, Cheshire, CH64 7TE, UK
| | - Michela Quaglia
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Campo Boario, 64100, Teramo, Italy
| | - Miguel Ángel Miranda-Chueca
- Applied Zoology and Animal Conservation Research Group, University of the Balearic Islands UIB, Palma, Spain
| | - René Bødker
- University of Copenhagen, Copenhagen, Denmark
| | - Rosa Estrada-Peña
- Department of Animal Pathology, AgriFood Institute of Aragón (IA2) Veterinary Faculty, 50013, Zaragoza, Spain
| | | | - Simona Tchakarova
- National Diagnostic and Research Veterinary Medical Institute, Sofia, Bulgaria
| | - Sofia Boutsini
- Department of Parasitology-Parasitic Diseases, Entomology & Bee Health, Veterinary Centre of Athens, Athens, Greece
| | | | - Stefanie M Schäfer
- Centre for Ecology, Centre for Ecology & Hydrology, Wallingford, OX10 8BB, UK
| | - Zanda Ozoliņa
- Institute of Food safety, Animal Health and Environment 'BIOR', Riga, Latvia
| | - Zanda Segliņa
- Institute of Food safety, Animal Health and Environment 'BIOR', Riga, Latvia
| | - Zati Vatansever
- Veterinary Control Central Research Institute, Ankara, Turkey
| | - Karine Huber
- ASTRE, Univ Montpellier, Cirad, INRAE, Montpellier, France
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17
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Federici V, Goffredo M, Mancini G, Quaglia M, Santilli A, Di Nicola F, De Ascentis M, Cabras P, Volpicelli C, De Liberato C, Satta G, Federico G, Leone A, Pisciella M, Portanti O, Pizzurro F, Teodori L, Savini G. Vector Competence of Italian Populations of Culicoides for Some Bluetongue Virus Strains Responsible for Recent Northern African and European Outbreaks. Viruses 2019; 11:E941. [PMID: 31614799 PMCID: PMC6832517 DOI: 10.3390/v11100941] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/08/2019] [Accepted: 10/09/2019] [Indexed: 12/15/2022] Open
Abstract
The distribution of Bluetongue virus (BTV) in Europe can be represented by two distinct and interconnected epidemiological systems (episystems), each characterized by different ecological characteristics and vector species. This study investigated the vector competence of Italian populations of Culicoides imicola and Culicoides obsoletus/scoticus to some representative BTV strains after artificial oral infection. The BTV strains were selected according to their ability to spread to one or both episystems and included BTV-4 ITA, responsible of the recent Italian and French BTV-4 outbreaks; the BTV-2 strain which caused the first BTV incursion in Italy, Corsica, and Balearic Islands; BTV-4 MOR, responsible for the epidemic in Morocco; and BTV-8, the strain which spread through Europe between 2006 and 2008. Blood-soaked cotton pledgets and Hemotek membrane feeder using Parafilm® membrane were used to artificially feed midges. For each population/strain, recovery rates (positive/tested heads) were evaluated using serogroup- and serotype-specific RT-PCR. The trial demonstrated that, except for the Abruzzo population of C. obsoletus/C. scoticus, which was refractory to BTV-4 MOR infection, all the investigated Culicoides populations are susceptible to the selected BTV strains and that, if prompt vaccination programs and restriction measures had not been implemented, BTV-2 and BTV-4 MOR could have spread all over Europe.
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Affiliation(s)
- Valentina Federici
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Maria Goffredo
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Giuseppe Mancini
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Michela Quaglia
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Adriana Santilli
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Francesca Di Nicola
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Matteo De Ascentis
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Pierangela Cabras
- Istituto Zooprofilattico Sperimentale della Sardegna, Via Duca degli Abruzzi 8, 07100 Sassari, Italy.
| | - Carmela Volpicelli
- Azienda Sanitaria Provinciale Crotone, Via M. Nicoletta, 88900 Crotone (KR), Italy.
| | - Claudio De Liberato
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana, Via Appia Nuova 1411, 00178 Rome, Italy.
| | - Giuseppe Satta
- Istituto Zooprofilattico Sperimentale della Sardegna, Via Duca degli Abruzzi 8, 07100 Sassari, Italy.
| | - Giovanni Federico
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Figurella, 89135 Catona (RC), Italy.
| | - Alessandra Leone
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Maura Pisciella
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Ottavio Portanti
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Federica Pizzurro
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Liana Teodori
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
| | - Giovanni Savini
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Via Campo Boario, 64100 Teramo, Italy.
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18
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Duan YL, Bellis G, Li L, Li HC, Miao HS, Kou ML, Liao DF, Wang Z, Gao L, Li JZ. Potential vectors of bluetongue virus in high altitude areas of Yunnan Province, China. Parasit Vectors 2019; 12:464. [PMID: 31585545 PMCID: PMC6778386 DOI: 10.1186/s13071-019-3736-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 09/30/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Bluetongue disease of ruminants is a typical insect-borne disease caused by bluetongue virus (BTV) of the genus Orbivirus (family Reoviridae) and transmitted by some species of Culicoides (Diptera: Ceratopogonidae). Recently, the detection of BTV in yaks in high altitude meadows of the Shangri-La district of Yunnan Province, China, prompted an investigation of the Culicoides fauna as potential vectors of BTV. METHODS A total of 806 Culicoides midges were collected by light trapping at three sites at altitudes ranging from 1800 to 3300 m. The species were identified based on morphology and the DNA sequences of cytochrome c oxidase subunit 1 (cox1). PCR and quantitative PCR following reverse transcription were used to test for the presence of BTV RNA in Culicoides spp. A phylogenetic analysis was used to analyze the cox1 sequences of some specimens. RESULTS Four species dominated these collections and cox1 barcoding revealed that at least two of these appear to belong to species new to science. Culicoides tainanus and a cryptic species morphologically similar to C. tainanus dominated low altitude valley collections while C. nielamensis was the most abundant species in the high-altitude meadow. A species related to C. obsoletus occurred at all altitudes but did not dominate any of the collections. BTV RT-qPCR analysis detected BTV RNA in two specimens of C. tainanus, in one specimen closely related to C. tainanus and in one specimen closely related to C. obsoletus by barcode sequencing. CONCLUSIONS This study suggests that BTV in high altitude areas of Yunnan is being transmitted by three species of Culicoides, two of which appear to be new to science. This research may be useful in improving understanding of the effects of global warming on arboviral disease epidemiology and further study is important in research into disease control and prevention.
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Affiliation(s)
- Ying Liang Duan
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan Province China
| | - Glenn Bellis
- Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, NT Australia
| | - Le Li
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan Province China
| | - Hua Chun Li
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan Province China
| | - Hai Sheng Miao
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan Province China
| | - Mei Ling Kou
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan Province China
| | - De Fang Liao
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan Province China
| | - Zheng Wang
- Zhongdian Animal Disease Control Center, Shangri-La, Yunnan Province China
| | - Lin Gao
- Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan Province China
| | - Ji Zhong Li
- Zhongdian Animal Disease Control Center, Shangri-La, Yunnan Province China
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Bourquia M, Garros C, Rakotoarivony I, Gardès L, Huber K, Boukhari I, Delécolle JC, Baldet T, Mignotte A, Lhor Y, Khallaayoune K, Balenghien T. Update of the species checklist of Culicoides Latreille, 1809 biting midges (Diptera: Ceratopogonidae) of Morocco. Parasit Vectors 2019; 12:459. [PMID: 31551074 PMCID: PMC6757417 DOI: 10.1186/s13071-019-3720-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 09/14/2019] [Indexed: 11/10/2022] Open
Abstract
Background Investigations of Culicoides fauna, including inventories, were carried out in Morocco at different periods after the country had faced major bluetongue and African horse sickness outbreaks. However, no comprehensive reference publication has provided a clear overview of the Culicoides species diversity. This study reviewed available data on Culicoides biting midge species in Morocco from 1968 to 2015 (published and grey literature in French and English) in order to revise the current checklist, in light of state of the art taxonomic and systematic knowledge, and confirmed the checklist with morphological and molecular identifications of specimens collected from the region of Rabat. Methods Literature related to Culicoides collections in Morocco was collated. Authors were contacted to obtain raw data and additional information for the collections. Fresh Culicoides material was collected and examined from two sites around Rabat, the capital of Morocco. Each collected individual was examined and morphologically identified, if possible, to the species level. In addition, molecular identification was performed to separate closely related species, to confirm difficult morphological identifications and to confirm new species records. Results A total of 6121 individuals of Culicoides spp. were collected and analyzed and at least 17 species were identified: C. cataneii/C. gejgelensis, C. circumscriptus, C. fagineus, C. festivipennis, C. imicola, C. jumineri, C. kingi, C. longipennis, C. montanus, C. newsteadi, C. obsoletus, C. paolae, C. parotti, C. puncticollis, C. sahariensis, C. scoticus and C. subfagineus. Seven species were confirmed using phylogenetic analyses. Two new species records for Morocco are reported: C. paolae and C. subfagineus. Conclusions The Moroccan fauna of Culicoides now includes 54 valid species. Further work would certainly increase this total, as one of the clades we identified was not affiliated to any described and valid species.
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Affiliation(s)
- Maria Bourquia
- Institut Agronomique et Vétérinaire Hassan II, Unité Parasitologie et Maladies Parasitaires, 10100, Rabat, Morocco. .,ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France. .,Cirad, UMR ASTRE, 34398, Montpellier, France.
| | - Claire Garros
- ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France.,Cirad, UMR ASTRE, 97490, Ste Clotilde, La Réunion, France
| | - Ignace Rakotoarivony
- ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France
| | - Laetitia Gardès
- ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France.,Cirad, UMR ASTRE, 97170, Petit-Bourg, Guadeloupe, France
| | - Karine Huber
- ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France
| | - Intissar Boukhari
- Institut Agronomique et Vétérinaire Hassan II, Unité Parasitologie et Maladies Parasitaires, 10100, Rabat, Morocco
| | - Jean-Claude Delécolle
- Institut de Parasitologie et de Pathologie Tropicale de Strasbourg (IPPTS) EA7292, 3 rue Koeberlé, 67000, Strasbourg, France
| | - Thierry Baldet
- ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France
| | - Antoine Mignotte
- ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France.,Cirad, UMR ASTRE, 34398, Montpellier, France
| | - Youssef Lhor
- Office National de Sécurité Sanitaire des Produits Alimentaires, Institut Agronomique et Vétérinaire, 10015, Rabat, Morocco
| | - Khalid Khallaayoune
- Institut Agronomique et Vétérinaire Hassan II, Unité Parasitologie et Maladies Parasitaires, 10100, Rabat, Morocco
| | - Thomas Balenghien
- ASTRE, Univ Montpellier, Cirad, INRA, Montpellier, France. .,Cirad, UMR ASTRE, 34398, Montpellier, France. .,Institut Agronomique et Vétérinaire Hassan II, Unité Microbiologie, Immunologie et Maladies Contagieuses, 10100, Rabat, Morocco.
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20
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Villard P, Muñoz F, Balenghien T, Baldet T, Lancelot R, Hénaux V. Modeling Culicoides abundance in mainland France: implications for surveillance. Parasit Vectors 2019; 12:391. [PMID: 31387649 PMCID: PMC6683357 DOI: 10.1186/s13071-019-3642-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/25/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Biting midges of the genus Culicoides Latreille (Diptera: Ceratopogonidae) are involved in the transmission of several viruses affecting humans and livestock, particularly bluetongue (BTV). Over the last decade, Culicoides surveillance has been conducted discontinuously and at various temporal and spatial scales in mainland France following the BTV epizootics in 2008-2009 and its reemergence and continuous circulation since 2015. The ability to predict seasonal dynamics and spatial abundance of Culicoides spp. is a key element in identifying periods and areas at high risk of transmission in order to strengthen surveillance for early detection and to establish seasonally disease-free zones. The objective of this study was to model the abundance of Culicoides spp. using surveillance data. METHODS A mixed-effect Poisson model, adjusted for overdispersion and taking into account temperature data at each trap location, was used to model the weekly relative abundance of Culicoides spp. over a year in 24 vector zones, based on surveillance data collected during 2009-2012. Vector zones are the spatial units used for Culicoides surveillance since 2016 in mainland France. RESULTS The curves of the predicted annual abundance of Culicoides spp. in vector zones showed three different shapes: unimodal, bimodal or plateau, reflecting the temporal variability of the observed counts between zones. For each vector zone, the model enabled to identify periods of vector activity ranging from 25 to 51 weeks. CONCLUSIONS Although the data were collected for surveillance purposes, our modeling approach integrating vector data with daily temperatures, which are known to be major drivers of Culicoides spp. activity, provided areas-specific predictions of Culicoides spp. abundance. Our findings provide decisions makers with essential information to identify risk periods in each vector zone and guide the allocation of resources for surveillance and control. Knowledge of Culicoides spp. dynamics is also of primary importance for modeling the risk of establishment and spread of midge-borne diseases in mainland France.
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Affiliation(s)
- Pierre Villard
- CIRAD, UMR ASTRE, 34398 Montpellier, France
- ASTRE, CIRAD, INRA, Université de Montpellier, Montpellier, France
- Unité Epidémiologie et Appui à la Surveillance, Laboratoire de Lyon, Université de Lyon - ANSES, 31 Avenue Tony Garnier, 69007 Lyon, France
| | - Facundo Muñoz
- CIRAD, UMR ASTRE, 34398 Montpellier, France
- ASTRE, CIRAD, INRA, Université de Montpellier, Montpellier, France
| | - Thomas Balenghien
- ASTRE, CIRAD, INRA, Université de Montpellier, Montpellier, France
- Unité Microbiologie, Immunologie et Maladies Contagieuses, Institut Agronomique et Vétérinaire Hassan II, 10100 Rabat, Morocco
- CIRAD, UMR ASTRE, 10101 Rabat, Morocco
| | - Thierry Baldet
- CIRAD, UMR ASTRE, 34398 Montpellier, France
- ASTRE, CIRAD, INRA, Université de Montpellier, Montpellier, France
| | - Renaud Lancelot
- CIRAD, UMR ASTRE, 34398 Montpellier, France
- ASTRE, CIRAD, INRA, Université de Montpellier, Montpellier, France
| | - Viviane Hénaux
- Unité Epidémiologie et Appui à la Surveillance, Laboratoire de Lyon, Université de Lyon - ANSES, 31 Avenue Tony Garnier, 69007 Lyon, France
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Bluetongue Virus in France: An Illustration of the European and Mediterranean Context since the 2000s. Viruses 2019; 11:v11070672. [PMID: 31340459 PMCID: PMC6669443 DOI: 10.3390/v11070672] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/05/2019] [Accepted: 07/19/2019] [Indexed: 01/24/2023] Open
Abstract
Bluetongue (BT) is a non-contagious animal disease transmitted by midges of the Culicoides genus. The etiological agent is the BT virus (BTV) that induces a variety of clinical signs in wild or domestic ruminants. BT is included in the notifiable diseases list of the World Organization for Animal Health (OIE) due to its health impact on domestic ruminants. A total of 27 BTV serotypes have been described and additional serotypes have recently been identified. Since the 2000s, the distribution of BTV has changed in Europe and in the Mediterranean Basin, with continuous BTV incursions involving various BTV serotypes and strains. These BTV strains, depending on their origin, have emerged and spread through various routes in the Mediterranean Basin and/or in Europe. Consequently, control measures have been put in place in France to eradicate the virus or circumscribe its spread. These measures mainly consist of assessing virus movements and the vaccination of domestic ruminants. Many vaccination campaigns were first carried out in Europe using attenuated vaccines and, in a second period, using exclusively inactivated vaccines. This review focuses on the history of the various BTV strain incursions in France since the 2000s, describing strain characteristics, their origins, and the different routes of spread in Europe and/or in the Mediterranean Basin. The control measures implemented to address this disease are also discussed. Finally, we explain the circumstances leading to the change in the BTV status of France from BTV-free in 2000 to an enzootic status since 2018.
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Emergence of a Novel Reassortant Strain of Bluetongue Serotype 6 in Israel, 2017: Clinical Manifestations of the Disease and Molecular Characterization. Viruses 2019; 11:v11070633. [PMID: 31295819 PMCID: PMC6669665 DOI: 10.3390/v11070633] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/03/2019] [Accepted: 07/09/2019] [Indexed: 12/19/2022] Open
Abstract
Reassortment contributes to the evolution of RNA viruses with segmented genomes, including Bluetongue virus (BTV). Recently, co-circulation of natural and vaccine BTV variants in Europe, and their ensuing reassortment, were proposed to promote appearance of novel European BTV strains, with potential implications for pathogenicity, spread and vaccination policies. Similarly, the geographical features of the Mediterranean basin, which spans over portions of three continents, may facilitate the appearance of clinically relevant reassortants via co-circulation of BTV strains of African, Asian and European origins. In August–October 2017, BTV serotype 6 (BTV-6) was identified in young animals exhibiting classical clinical signs of Bluetongue (BT) at Israeli sheep and cattle farms. Sequencing and pairwise analysis of this Israeli BTV-6 isolate revealed the closest sequence homology of its serotype-defining Segment 2 was with that of South African reference BTV-6 strain 5011 (93.88% identity). In contrast, the other viral segments showed highest homology (97.0%–99.47% identity) with BTV-3, -4 and -9 of Mediterranean and African origins. Specifically, four viral segments were nearly identical (99.13%–99.47%), with Tunisian and Italian BTV-3 strains (TUN2016 and SAD2018, correspondingly). Together, our data suggest that Mediterranean co-circulation and reassortment of BTV-3 and BTV-6 drove the emergence of a novel and virulent BTV-6 strain
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Rojas JM, Rodríguez-Martín D, Martín V, Sevilla N. Diagnosing bluetongue virus in domestic ruminants: current perspectives. VETERINARY MEDICINE-RESEARCH AND REPORTS 2019; 10:17-27. [PMID: 30859085 PMCID: PMC6385761 DOI: 10.2147/vmrr.s163804] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
This review provides an overview of current and potential new diagnostic techniques against bluetongue virus (BTV), an Orbivirus transmitted by arthropods that affects ruminants. Bluetongue is a disease currently notifiable to the World Organization for Animal Health (OIE), causing great economic losses due to decreased trade associated with bluetongue outbreaks and high mortality and morbidity. BTV cross-reacts with many antigenically related viruses including viruses that causes African Horse sickness and epizootic haemorrhagic disease of deer. Therefore, reliable diagnostic approaches to detect BTV among these other antigenically related viruses are used or being developed. The antigenic determinant for differentiation of virus species/serogroups among orbiviruses is the VP7 protein, meanwhile VP2 is serotype specific. Serologically, assays are established in many laboratories, based mainly on competitive ELISA or serum neutralization assay (virus neutralization assay [VNT]) although new techniques are being developed. Virus isolation from blood or semen is, additionally, another means of BTV diagnosis. Nevertheless, most of these techniques for viral isolation are time-consuming and expensive. Currently, reverse-transcription polymerase chain reaction (RT-PCR) panels or real-time RT-PCR are widely used methods although next-generation sequencing remains of interest for future virus diagnosis.
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Affiliation(s)
- José M Rojas
- Centro de Investigación en Sanidad Animal (CISA-INIA), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Valdeolmos, Madrid, Spain,
| | - Daniel Rodríguez-Martín
- Centro de Investigación en Sanidad Animal (CISA-INIA), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Valdeolmos, Madrid, Spain,
| | - Verónica Martín
- Centro de Investigación en Sanidad Animal (CISA-INIA), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Valdeolmos, Madrid, Spain,
| | - Noemí Sevilla
- Centro de Investigación en Sanidad Animal (CISA-INIA), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Valdeolmos, Madrid, Spain,
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24
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Cuéllar AC, Jung Kjær L, Baum A, Stockmarr A, Skovgard H, Nielsen SA, Andersson MG, Lindström A, Chirico J, Lühken R, Steinke S, Kiel E, Gethmann J, Conraths FJ, Larska M, Smreczak M, Orłowska A, Hamnes I, Sviland S, Hopp P, Brugger K, Rubel F, Balenghien T, Garros C, Rakotoarivony I, Allène X, Lhoir J, Chavernac D, Delécolle JC, Mathieu B, Delécolle D, Setier-Rio ML, Venail R, Scheid B, Chueca MÁM, Barceló C, Lucientes J, Estrada R, Mathis A, Tack W, Bødker R. Monthly variation in the probability of presence of adult Culicoides populations in nine European countries and the implications for targeted surveillance. Parasit Vectors 2018; 11:608. [PMID: 30497537 PMCID: PMC6267925 DOI: 10.1186/s13071-018-3182-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 11/05/2018] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are small hematophagous insects responsible for the transmission of bluetongue virus, Schmallenberg virus and African horse sickness virus to wild and domestic ruminants and equids. Outbreaks of these viruses have caused economic damage within the European Union. The spatio-temporal distribution of biting midges is a key factor in identifying areas with the potential for disease spread. The aim of this study was to identify and map areas of neglectable adult activity for each month in an average year. Average monthly risk maps can be used as a tool when allocating resources for surveillance and control programs within Europe. METHODS We modelled the occurrence of C. imicola and the Obsoletus and Pulicaris ensembles using existing entomological surveillance data from Spain, France, Germany, Switzerland, Austria, Denmark, Sweden, Norway and Poland. The monthly probability of each vector species and ensembles being present in Europe based on climatic and environmental input variables was estimated with the machine learning technique Random Forest. Subsequently, the monthly probability was classified into three classes: Absence, Presence and Uncertain status. These three classes are useful for mapping areas of no risk, areas of high-risk targeted for animal movement restrictions, and areas with an uncertain status that need active entomological surveillance to determine whether or not vectors are present. RESULTS The distribution of Culicoides species ensembles were in agreement with their previously reported distribution in Europe. The Random Forest models were very accurate in predicting the probability of presence for C. imicola (mean AUC = 0.95), less accurate for the Obsoletus ensemble (mean AUC = 0.84), while the lowest accuracy was found for the Pulicaris ensemble (mean AUC = 0.71). The most important environmental variables in the models were related to temperature and precipitation for all three groups. CONCLUSIONS The duration periods with low or null adult activity can be derived from the associated monthly distribution maps, and it was also possible to identify and map areas with uncertain predictions. In the absence of ongoing vector surveillance, these maps can be used by veterinary authorities to classify areas as likely vector-free or as likely risk areas from southern Spain to northern Sweden with acceptable precision. The maps can also focus costly entomological surveillance to seasons and areas where the predictions and vector-free status remain uncertain.
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Affiliation(s)
- Ana Carolina Cuéllar
- Division for Diagnostics and Scientific Advice, National Veterinary Institute, Technical University of Denmark (DTU), Lyngby, Denmark
| | - Lene Jung Kjær
- Division for Diagnostics and Scientific Advice, National Veterinary Institute, Technical University of Denmark (DTU), Lyngby, Denmark
| | - Andreas Baum
- Department of Applied Mathematics and Computer Science, Technical University of Denmark (DTU), Lyngby, Denmark
| | - Anders Stockmarr
- Department of Applied Mathematics and Computer Science, Technical University of Denmark (DTU), Lyngby, Denmark
| | - Henrik Skovgard
- Department of Agroecology - Entomology and Plant Pathology, Aarhus University, Aarhus, Denmark
| | - Søren Achim Nielsen
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | | | | | - Jan Chirico
- National Veterinary Institute (SVA), Uppsala, Sweden
| | - Renke Lühken
- Bernhard Nocht Institute for Tropical Medicine, WHO Collaborating Centre for Arbovirus and Hemorrhagic Fever Reference and Research National Reference Centre for Tropical Infectious Diseases, Hamburg, Germany
| | - Sonja Steinke
- Department of Biology and Environmental Sciences, Carl von Ossietzky University, Oldenburg, Germany
| | - Ellen Kiel
- Department of Biology and Environmental Sciences, Carl von Ossietzky University, Oldenburg, Germany
| | - Jörn Gethmann
- Institute of Epidemiology, Friedrich Loeffler Institute, Greifswald, Germany
| | - Franz J. Conraths
- Institute of Epidemiology, Friedrich Loeffler Institute, Greifswald, Germany
| | - Magdalena Larska
- Department of Virology, National Veterinary Research Institute, Pulawy, Poland
| | - Marcin Smreczak
- Department of Virology, National Veterinary Research Institute, Pulawy, Poland
| | - Anna Orłowska
- Department of Virology, National Veterinary Research Institute, Pulawy, Poland
| | | | | | - Petter Hopp
- Norwegian Veterinary Institute, Oslo, Norway
| | | | - Franz Rubel
- Institute for Veterinary Public Health, Vetmeduni, Vienna, Austria
| | | | | | | | | | | | | | - Jean-Claude Delécolle
- Institute of Parasitology and Tropical Pathology of Strasbourg, EA7292, Université de Strasbourg, Strasbourg, France
| | - Bruno Mathieu
- Institute of Parasitology and Tropical Pathology of Strasbourg, EA7292, Université de Strasbourg, Strasbourg, France
| | - Delphine Delécolle
- Institute of Parasitology and Tropical Pathology of Strasbourg, EA7292, Université de Strasbourg, Strasbourg, France
| | | | - Roger Venail
- EID Méditerranée, Montpellier, France
- Avia-GIS NV, Zoersel, Belgium
| | | | | | - Carlos Barceló
- Laboratory of Zoology, University of the Balearic Islands, Palma, Spain
| | - Javier Lucientes
- Department of Animal Pathology, University of Zaragoza, Zaragoza, Spain
| | - Rosa Estrada
- Department of Animal Pathology, University of Zaragoza, Zaragoza, Spain
| | - Alexander Mathis
- Institute of Parasitology, University of Zürich, Zürich, Switzerland
| | | | - René Bødker
- Division for Diagnostics and Scientific Advice, National Veterinary Institute, Technical University of Denmark (DTU), Lyngby, Denmark
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Hope A, Gubbins S, Sanders C, Barber J, Stubbins F, Baylis M, Carpenter S. Sheep breed and shearing influences attraction and blood-feeding behaviour of Culicoides (Diptera: Ceratopogonidae) on a UK farm. Parasit Vectors 2018; 11:473. [PMID: 30126453 PMCID: PMC6102838 DOI: 10.1186/s13071-018-3003-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 07/09/2018] [Indexed: 11/30/2022] Open
Abstract
Background Culicoides biting midges (Diptera: Ceratopogonidae) are responsible for the biological transmission of arboviruses of international importance between ruminant livestock. These arboviruses include bluetongue virus (BTV) and Schmallenberg virus (SBV), which have emerged in unprecedented outbreaks in northern Europe. The impact of breed and shearing of sheep on Culicoides: host contact rates has not been investigated in detail and has the potential to influence arbovirus transmission and control measures employed to limit spread. Methods Attraction of Culicoides to Hartline and Hartline/Suffolk cross-breed sheep was compared using 224 drop trap collections over 22 nights and 181 catches from sheared or unsheared Hartline/Suffolk ewes were made over 17 nights to compare Culicoides activity and rates of blood engorgement. Results A total of 31,314 Culicoides was collected in the two trials and females of the subgenus Avaritia represented over 96.9% of individuals collected. Attraction to breed was dependent upon species of Culicoides and physiological status, with a significantly greater number of individuals collected on the cross-breed sheep. Shearing of sheep did not significantly increase or decrease the number of Culicoides attracted but increased the rate of successful engorgement. Conclusions Both breed and shearing were shown to influence Culicoides biting rate on sheep. These data are useful in a direct context in understanding the likely impact of control measures against arboviruses including BTV and SBV and additionally in providing data from field-based studies to enable modelling exercises of arbovirus transmission and spread. Electronic supplementary material The online version of this article (10.1186/s13071-018-3003-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Andrew Hope
- The Pirbright Institute, Pirbright, Surrey, UK.
| | | | | | | | | | - Matthew Baylis
- Liverpool University Climate and Infectious Diseases of Animals (Lucinda) Group, University of Liverpool, Neston, Cheshire, UK.,Health Protection Research Unit in Emerging and Zoonotic Infections, University of Liverpool, Liverpool, UK
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Paslaru AI, Mathis A, Torgerson P, Veronesi E. Vector competence of pre-alpine Culicoides (Diptera: Ceratopogonidae) for bluetongue virus serotypes 1, 4 and 8. Parasit Vectors 2018; 11:466. [PMID: 30103803 PMCID: PMC6090685 DOI: 10.1186/s13071-018-3050-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 08/03/2018] [Indexed: 12/02/2022] Open
Abstract
Background Bluetongue disease, caused by bluetongue virus serotype 8 (BTV-8), appeared for the first time in the northern part of Europe in 2006, and subsequently rapidly spread causing severe economic losses to the farming industry. The implicated vectors of BTV in Europe are Culicoides species within the subgenus Avaritia (C. chiopterus, C. dewulfi, C. obsoletus and C. scoticus). Epidemiological data from Switzerland have shown that BTV, whose spread was eliminated at an early stage by vaccination campaigns, had not been circulating among livestock at higher altitudes where other species dominate the Culicoides fauna. In this study, we investigated the extent that Culicoides spp. prevailing at higher altitudes (mainly C. grisescens) can act as vectors for BTV. Methods Culicoides were collected at farms in the pre-alpine region (two sites at 1550 m above sea level, masl, referred to as pre-alpine I; one site at 2030 masl, pre-alpine II) and, for comparative purposes, from the Swiss Plateau (one site, 650 masl). They were fed on bovine blood/BTV suspensions (BTV-1, 4 or 8) and incubated for eight days under a fluctuating temperature regime (13–25 °C, mean 19 °C), reflecting a mid-summer warm spell in the pre-alpine region. Susceptibility to BTV transmission was assessed from head homogenates by RT-qPCR and virus isolation. Results Overall, 9196 female Culicoides were exposed to the three BTV strains through an artificial membrane, with feeding rates of 14–27%. Survival rates of blood-engorged Culicoides females at eight days post-infection depended on both virus serotype and altitude of origin. Virus dissemination (Cq ≤ the cut-off value as determined by serial virus dilutions) was confirmed only for BTV-1 in C. scoticus (dissemination efficiency 22.5%; 9/40) and C. obsoletus (5.6%; 1/18) from the Swiss Plateau area. There was no strong evidence of susceptibility to infection for Culicoides from the pre-alpine area when fed with all BTV strains (BTV-1, 4 and 8). Conclusions This study confirms the susceptibility of C. scoticus and C. obsoletus to BTV-1 infection, including under cooler temperatures. Culicoides grisescens, which is highly abundant at higher altitudes, cannot be considered a potential vector under these temperature conditions. Electronic supplementary material The online version of this article (10.1186/s13071-018-3050-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anca Ioana Paslaru
- National Centre for Vector Entomology, Institute of Parasitology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland
| | - Alexander Mathis
- National Centre for Vector Entomology, Institute of Parasitology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland
| | - Paul Torgerson
- Section of Epidemiology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland
| | - Eva Veronesi
- National Centre for Vector Entomology, Institute of Parasitology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland.
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Wilson AJ, Harrup LE. Reproducibility and relevance in insect-arbovirus infection studies. CURRENT OPINION IN INSECT SCIENCE 2018; 28:105-112. [PMID: 30551760 PMCID: PMC6299244 DOI: 10.1016/j.cois.2018.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/03/2018] [Accepted: 05/16/2018] [Indexed: 06/09/2023]
Abstract
Experimental infections of insects with arboviruses are performed to achieve a variety of objectives but principally to draw inferences about the potential role of field populations in transmission or to explore the molecular basis of vector-pathogen interactions. The design of such studies determines both their reproducibility and the extent to which their results can be extrapolated to natural environments, and is constrained by the resources available. We discuss recent findings regarding the effects of nutrition, the microbiome, co-infecting agents and feeding methods on the outcome of such experiments, and identify resource-efficient ways to increase their relevance and reproducibility, including the development of community standards for reporting such studies and better standards for cell line and colony authentication.
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Affiliation(s)
- Anthony James Wilson
- The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey GU24 0NF, United Kingdom.
| | - Lara Ellen Harrup
- The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey GU24 0NF, United Kingdom
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Talavera S, Muñoz-Muñoz F, Verdún M, Pujol N, Pagès N. Revealing potential bridge vectors for BTV and SBV: a study on Culicoides blood feeding preferences in natural ecosystems in Spain. MEDICAL AND VETERINARY ENTOMOLOGY 2018; 32:35-40. [PMID: 28857265 DOI: 10.1111/mve.12263] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/28/2017] [Accepted: 06/09/2017] [Indexed: 05/26/2023]
Abstract
Several species of Culicoides (Diptera: Ceratopogonidae) are vectors of pathogens, such as the bluetongue (BTV) and Schmallenberg (SBV) viruses, which cause important diseases in domestic and wild ruminants. As wild ruminants can contribute to overwintering and epizootics of both diseases, knowledge of the host-feeding behaviour of Culicoides in natural ecosystems is important to better understand their epidemiology. Blood-engorged Culicoides females trapped in natural areas inhabited by different wild ruminant species were genetically analysed to identify host species. The origin of bloodmeals was identified in 114 females of 14 species of Culicoides. A total of 104 (91.1%) Culicoides fed on mammals and 10 (8.9%) on birds. The most abundant host identified was red deer (66.7%), followed by humans (13%) and fallow deer (6.1%). Eleven of the 14 species of Culicoides fed exclusively on mammalian hosts. Among them, five are mammalophilic species considered to be important BTV and/or SBV vectors. The results of the present study confirm that Culicoides imicola, Culicoides obsoletus, Culicoides scoticus, Culicoides pulicaris and Culicoides punctatus fed on wild ruminants, and therefore support the hypothesis that these species can act as bridge vectors by facilitating the circulation of pathogens between wild and domestic ruminant communities.
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Affiliation(s)
- S Talavera
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Bellaterra, Spain
| | - F Muñoz-Muñoz
- Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - M Verdún
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Bellaterra, Spain
| | - N Pujol
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Bellaterra, Spain
| | - N Pagès
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Bellaterra, Spain
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Pagès N, Talavera S, Verdún M, Pujol N, Valle M, Bensaid A, Pujols J. Schmallenberg virus detection in Culicoides biting midges in Spain: First laboratory evidence for highly efficient infection of Culicoides of the Obsoletus complex and Culicoides imicola. Transbound Emerg Dis 2018; 65:e1-e6. [PMID: 28474491 DOI: 10.1111/tbed.12653] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Indexed: 11/30/2022]
Abstract
Since Schmallenberg disease was discovered in 2011, the disease rapidly spread across Europe. Culicoides biting midges have been implicated as putative Schmallenberg vectors in Europe. The detection of Schmallenberg virus (SBV) in field collected Culicoides was evaluated through retrospective (2011-2012) collections and captures performed in 2013. This study represents the first detection of SBV in field collected Culicoides in Spain. Infectious midges were detected at the foothills of Pyrenees, Aramunt, in the summer 2012. All the specimens infected with Schmallenberg were of the species Culicoides obsoletus s.s. confirming its putative vector status in Spain. Experimental infection on field collected Culicoides provided evidence of atypical high efficiency for SBV vector infection and transmission potential in local populations of Culicoides imicola and in Culicoides of the Obsoletus complex. However, captured individuals of C. imicola were more susceptible to SBV infection than C. obsoletus s.l. (p < .001), with an infection ratio of 0.94 and 0.63, respectively. In contrast, a Culicoides nubeculosus colony appeared to be refractory to SBV infection.
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Affiliation(s)
- N Pagès
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - S Talavera
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - M Verdún
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - N Pujol
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - M Valle
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - A Bensaid
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - J Pujols
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Spain
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Talavera S, Muñoz-Muñoz F, Verdún M, Pagès N. Morphology and DNA barcoding reveal three species in one: description of Culicoides cryptipulicaris sp. nov. and Culicoides quasipulicaris sp. nov. in the subgenus Culicoides. MEDICAL AND VETERINARY ENTOMOLOGY 2017; 31:178-191. [PMID: 28370147 DOI: 10.1111/mve.12228] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 10/27/2016] [Accepted: 11/10/2016] [Indexed: 06/07/2023]
Abstract
Species of the genus Culicoides (Diptera: Ceratopogonidae) are well known for their importance in the field of medical and veterinary entomology. Culicoides spp. transmit a wide variety of pathogens, primarily viruses that affect animals and humans. In Europe, the most economically important disease transmitted by Culicoides is bluetongue (BT). Culicoides spp. have been recently involved as primary vectors for Schmallenberg disease. The taxonomy within the subgenus Culicoides has been historically difficult and reorganizations have been proposed regularly. The subgenus Culicoides includes species that are considered to be potential vectors for BT. High morphological intraspecific variability has been attributed to these species. This highlights the apparent presence of previously undetected cryptic species diversity in the subgenus. In the present study, a detailed morphological and molecular study of specimens belonging to Culicoides pulicaris s.l. and specimens resembling a cross between C. pulicaris and Culicoides punctatus revealed the presence of two new species: Culicoides cryptipulicaris and Culicoides quasipulicaris. Females of C. quasipulicaris and males of both species were morphologically distinguished from C. pulicaris (Linnaeus, 1758), whereas females of C. cryptipulicaris were identified using molecular techniques exclusively.
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Affiliation(s)
- S Talavera
- Institut de Recerca i Tecnologia (IRTA), Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona, Barcelona, Spain
| | - F Muñoz-Muñoz
- Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - M Verdún
- Institut de Recerca i Tecnologia (IRTA), Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona, Barcelona, Spain
| | - N Pagès
- Institut de Recerca i Tecnologia (IRTA), Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona, Barcelona, Spain
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Abstract
Bluetongue virus (BTV) is the type species of genus Orbivirus within family Reoviridae. Bluetongue virus is transmitted between its ruminant hosts by the bite of Culicoides spp. midges. Severe BT cases are characterized by symptoms including hemorrhagic fever, particularly in sheep, loss of productivity, and death. To date, 27 BTV serotypes have been documented. These include novel isolates of atypical BTV, which have been almost fully characterized using deep sequencing technologies and do not rely on Culicoides vectors for their transmission among hosts. Due to its high economic impact, BT is an Office International des Epizooties (OIE) listed disease that is strictly controlled in international commercial exchanges. During the 20th century, BTV has been endemic in subtropical regions. In the last 15 years, novel strains of nine "typical" BTV serotypes (1, 2, 4, 6, 8, 9, 11, 14, and 16) invaded Europe, some of which caused disease in naive sheep and unexpectedly in bovine herds (particularly serotype 8). Over the past few years, three novel "atypical" serotypes (25-27) were characterized during sequencing studies of animal samples from Switzerland, Kuwait, and France, respectively. Classical serotype-specific inactivated vaccines, although expensive, were very successful in controlling outbreaks as shown with the northern European BTV-8 outbreak which started in the summer of 2006. Technological jumps in deep sequencing methodologies made rapid full characterizations of BTV genome from isolates/tissues feasible. Next-generation sequencing (NGS) approaches are powerful tools to study the variability of BTV genomes on a fine scale. This paper provides information on how NGS impacted our knowledge of the BTV genome.
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Foxi C, Delrio G, Falchi G, Marche MG, Satta G, Ruiu L. Role of different Culicoides vectors (Diptera: Ceratopogonidae) in bluetongue virus transmission and overwintering in Sardinia (Italy). Parasit Vectors 2016; 9:440. [PMID: 27502924 PMCID: PMC4977893 DOI: 10.1186/s13071-016-1733-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 07/28/2016] [Indexed: 11/25/2022] Open
Abstract
Background Bluetongue (BT) epidemics have affected the Mediterranean island of Sardinia since 2000. While Culicoides imicola represents the main bluetongue virus (BTV) vector, other European Culicoides biting midges, possibly implicated in virus transmission, have been detected here. Understanding their distribution, seasonal abundance, and infection rates is necessary to predict disease incidence and spread across coastal and inland areas, and to define their role in virus overwintering. Methods Biting midge abundance was determined by light traps on selected farms representing diverse climatic conditions of Sardinia. Livestock-associated Culicoides species were morphologically and molecularly identified. Infection rates in prevailing midge species captured in 2013 during a BTV-1 outbreak were determined using RT-qPCR based virus detection in insect body pools, supplemented by specific body region analyses. The seasonal infection prevalence in Culicoides samples collected in 2001 in a BTV-2 affected farm was also determined. Results The Newsteadi complex (C. newsteadi species A and species B) prevailed among all biting midge species (47.7 %), followed by C. imicola (27.8 %) and the Obsoletus complex (C. obsoletus and C. scoticus) (17.6 %). Whilst Culicoides imicola was more abundant along the coast, the Newsteadi complex was frequently collected at higher altitude and the Obsoletus complex was notably associated to cattle farms. Culicoides pulicaris and C. punctatus abundance was found to be marginal in all farms. BTV was detected in parous female samples of all these species, and the full dissemination of the virus within the body of C. imicola, C. obsoletus, C. scoticus, and Newsteadi complex species was confirmed by analyses of thorax and head, containing salivary glands. Higher infection rates were associated with C. scoticus, C. newsteadi species A and species B, compared to C. imicola. The virus was detected in C. newsteadi species A and C. obsoletus in winter and spring, whereas it was mainly found in summer and autumn in C. imicola. Conclusions In Sardinia, bluetongue virus is transmitted by multiple Culicoides vectors, including C. imicola and the Newsteadi complex being the most important. The Newsteadi complex and other midge species can play an important role in internal areas and are likely to be directly involved in virus overwintering.
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Affiliation(s)
- Cipriano Foxi
- Dipartimento di Agraria, University of Sassari, Via E. De Nicola, Sassari, Italy
| | - Gavino Delrio
- Dipartimento di Agraria, University of Sassari, Via E. De Nicola, Sassari, Italy
| | - Giovanni Falchi
- Dipartimento di Agraria, University of Sassari, Via E. De Nicola, Sassari, Italy
| | | | - Giuseppe Satta
- Istituto Zooprofilattico Sperimentale della Sardegna, Via Duca degli Abruzzi 8, Sassari, Italy
| | - Luca Ruiu
- Dipartimento di Agraria, University of Sassari, Via E. De Nicola, Sassari, Italy.
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Ruder MG, Lysyk TJ, Stallknecht DE, Foil LD, Johnson DJ, Chase CC, Dargatz DA, Gibbs EPJ. Transmission and Epidemiology of Bluetongue and Epizootic Hemorrhagic Disease in North America: Current Perspectives, Research Gaps, and Future Directions. Vector Borne Zoonotic Dis 2016; 15:348-63. [PMID: 26086556 DOI: 10.1089/vbz.2014.1703] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are arthropod-transmitted viruses in the genus Orbivirus of the family Reoviridae. These viruses infect a variety of domestic and wild ruminant hosts, although the susceptibility to clinical disease associated with BTV or EHDV infection varies greatly among host species, as well as between individuals of the same species. Since their initial detection in North America during the 1950s, these viruses have circulated in endemic and epidemic patterns, with occasional incursions to more northern latitudes. In recent years, changes in the pattern of BTV and EHDV infection and disease have forced the scientific community to revisit some fundamental areas related to the epidemiology of these diseases, specifically in relation to virus-vector-host interactions and environmental factors that have potentially enabled the observed changes. The aim of this review is to identify research and surveillance gaps that obscure our understanding of BT and EHD in North America.
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Affiliation(s)
- Mark G Ruder
- 1 Arthropod-Borne Animal Diseases Research Unit, Agricultural Research Service , United States Department of Agriculture, Manhattan, Kansas
| | - Timothy J Lysyk
- 2 Research Centre , Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada
| | - David E Stallknecht
- 3 Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia , Athens, Georgia
| | - Lane D Foil
- 4 Bob Jones Wildlife Research Institute, Louisiana State University Agcenter , Idlewild, Louisiana
| | - Donna J Johnson
- 5 National Veterinary Services Laboratories, Science, Technologies and Analysis Services (STAS), Veterinary Services, Animal and Plant Health Inspection Service , United States Department of Agriculture, Ames, Iowa
| | - Christopher C Chase
- 6 Department of Veterinary and Biomedical Sciences, South Dakota State University , Brookings, South Dakota
| | - David A Dargatz
- 7 Center for Epidemiology and Animal Health , STAS, Veterinary Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, Colorado
| | - E Paul J Gibbs
- 8 Department of Infectious Diseases and Pathology, College of Veterinary Medicine, University of Florida , Gainesville, Florida
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Talavera S, Muñoz-Muñoz F, Durán M, Verdún M, Soler-Membrives A, Oleaga Á, Arenas A, Ruiz-Fons F, Estrada R, Pagès N. Culicoides Species Communities Associated with Wild Ruminant Ecosystems in Spain: Tracking the Way to Determine Potential Bridge Vectors for Arboviruses. PLoS One 2015; 10:e0141667. [PMID: 26510136 PMCID: PMC4624870 DOI: 10.1371/journal.pone.0141667] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 10/11/2015] [Indexed: 01/04/2023] Open
Abstract
The genus Culicoides Latreille 1809 is a well-known vector for protozoa, filarial worms and, above all, numerous viruses. The Bluetongue virus (BTV) and the recently emerged Schmallenberg virus (SBV) are responsible for important infectious, non-contagious, insect-borne viral diseases found in domestic ruminants and transmitted by Culicoides spp. Both of these diseases have been detected in wild ruminants, but their role as reservoirs during the vector-free season still remains relatively unknown. In fact, we tend to ignore the possibility of wild ruminants acting as a source of disease (BTV, SBV) and permitting its reintroduction to domestic ruminants during the following vector season. In this context, a knowledge of the composition of the Culicoides species communities that inhabit areas where there are wild ruminants is of major importance as the presence of a vector species is a prerequisite for disease transmission. In this study, samplings were conducted in areas inhabited by different wild ruminant species; samples were taken in both 2009 and 2010, on a monthly basis, during the peak season for midge activity (in summer and autumn). A total of 102,693 specimens of 40 different species of the genus Culicoides were trapped; these included major BTV and SBV vector species. The most abundant vector species were C. imicola and species of the Obsoletus group, which represented 15% and 11% of total numbers of specimens, respectively. At the local scale, the presence of major BTV and SBV vector species in areas with wild ruminants coincided with that of the nearest sentinel farms included in the Spanish Bluetongue Entomological Surveillance Programme, although their relative abundance varied. The data suggest that such species do not exhibit strong host specificity towards either domestic or wild ruminants and that they could consequently play a prominent role as bridge vectors for different pathogens between both types of ruminants. This finding would support the hypothesis that wild ruminants could act as reservoirs for such pathogens, and subsequently be involved in the reintroduction of disease to livestock on neighbouring farms.
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Affiliation(s)
- Sandra Talavera
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
- * E-mail:
| | - Francesc Muñoz-Muñoz
- Departament de Biologia Animal, de Biologia Vegetal i d’Ecologia, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Mauricio Durán
- Health and Biotechnology (SaBio) group, Instituto de Investigación en Recursos Cinegéticos (IREC), Ciudad Real, Castilla la Mancha, Spain
| | - Marta Verdún
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Anna Soler-Membrives
- Departament de Biologia Animal, de Biologia Vegetal i d’Ecologia, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Álvaro Oleaga
- Health and Biotechnology (SaBio) group, Instituto de Investigación en Recursos Cinegéticos (IREC), Ciudad Real, Castilla la Mancha, Spain
- SERPA, Sociedad de Servicios del Principado de Asturias S.A., Gijón, Asturias, Spain
| | - Antonio Arenas
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de Córdoba (UCO), Córdoba, Andalucía, Spain
| | - Francisco Ruiz-Fons
- Health and Biotechnology (SaBio) group, Instituto de Investigación en Recursos Cinegéticos (IREC), Ciudad Real, Castilla la Mancha, Spain
| | - Rosa Estrada
- Department of Animal Pathology, Faculty of Veterinary, University of Zaragoza, Zaragoza, Spain
| | - Nitu Pagès
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
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DE Regge N, DE Deken R, Fassotte C, Losson B, Deblauwe I, Madder M, Vantieghem P, Tomme M, Smeets F, Cay AB. Culicoides monitoring in Belgium in 2011: analysis of spatiotemporal abundance, species diversity and Schmallenberg virus detection. MEDICAL AND VETERINARY ENTOMOLOGY 2015; 29:263-275. [PMID: 25761054 DOI: 10.1111/mve.12109] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 11/27/2014] [Accepted: 12/04/2014] [Indexed: 06/04/2023]
Abstract
In 2011, Culicoides (Diptera: Ceratopogonidae) were collected at 16 locations covering four regions of Belgium with Onderstepoort Veterinary Institute (OVI) traps and at two locations with Rothamsted suction traps (RSTs). Quantification of the collections and morphological identification showed important variations in abundance and species diversity between individual collection sites, even for sites located in the same region. However, consistently higher numbers of Culicoides midges were collected at some sites compared with others. When species abundance and diversity were analysed at regional level, between-site variation disappeared. Overall, species belonging to the subgenus Avaritia together with Culicoides pulicaris (subgenus Culicoides) were the most abundant, accounting for 80% and 96% of all midges collected with RSTs and OVI traps, respectively. Culicoides were present during most of the year, with Culicoides obsoletus complex midges found from 9 February until 27 December. Real-time reverse-transcription polymerase chain reaction screening for Schmallenberg virus in the heads of collected midges resulted in the first detection of the virus in August 2011 and identified C. obsoletus complex, Culicoides chiopterus and Culicoides dewulfi midges as putative vector species. At Libramont in the south of Belgium, no positive pools were identified.
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Affiliation(s)
- N DE Regge
- Operational Direction Viral Diseases, Veterinary and Agrochemical Research Centre (CODA-CERVA), Brussels, Belgium
| | - R DE Deken
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - C Fassotte
- Plant Protection and Ecotoxicology, Life Science Department, Walloon Agricultural Research Centre (CRA-W), Gembloux, Belgium
| | - B Losson
- Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
| | - I Deblauwe
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - M Madder
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
| | - P Vantieghem
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - M Tomme
- Plant Protection and Ecotoxicology, Life Science Department, Walloon Agricultural Research Centre (CRA-W), Gembloux, Belgium
| | - F Smeets
- Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
| | - A B Cay
- Operational Direction Viral Diseases, Veterinary and Agrochemical Research Centre (CODA-CERVA), Brussels, Belgium
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Orientation behaviour of Culicoides obsoletus (Diptera: Ceratopogonidae), a relevant virus vector in northern Europe, toward host-associated odorant cues. Vet Parasitol 2015; 211:274-82. [DOI: 10.1016/j.vetpar.2015.05.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 05/11/2015] [Accepted: 05/12/2015] [Indexed: 11/15/2022]
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Zimmer JY, Brostaux Y, Haubruge E, Francis F. Larval development sites of the main Culicoides species (Diptera: Ceratopogonidae) in northern Europe and distribution of coprophilic species larvae in Belgian pastures. Vet Parasitol 2014; 205:676-86. [PMID: 25241330 DOI: 10.1016/j.vetpar.2014.08.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Revised: 08/16/2014] [Accepted: 08/28/2014] [Indexed: 11/16/2022]
Abstract
Some Culicoides species of biting midges (Diptera: Ceratopogonidae) are biological virus vectors worldwide and have indeed been associated with outbreaks of important epizoonoses in recent years, such as bluetongue and Schmallenberg disease in northern Europe. These diseases, which affect domestic and wild ruminants, have caused considerable economic losses. Knowledge of substrates suitable for Culicoides larval development is important, particularly for the main vector temperate species. This study, realized during two years, aimed to highlight the larval development sites of these biting midge species in the immediate surroundings of ten Belgian cattle farms. Moreover, spatial distribution of the coprophilic Culicoides larvae (C. chiopterus and C. dewulfi) within pastures was studied with increasing distance from farms along linear transects (farm-pasture-woodland). A total of 4347 adult specimens belonging to 13 Culicoides species were obtained by incubation of 2131 soil samples belonging to 102 different substrates; 18 of these substrates were suitable for larval development. The Obsoletus complex (formed by two species) was observed in a wide range of substrates, including silage residues, components of a chicken coop, dung adhering to walls inside stables, leftover feed along the feed bunk, a compost pile of sugar beet residues, soil of a livestock trampling area, and decaying wood, while the following served as substrates for the other specimens: C. chiopterus, mainly cow dung; C. dewulfi, cow dung and molehill soil; C. circumscriptus, algae; C. festivipennis, algae and soil in stagnant water; C. nubeculosus, algae and silt specifically from the edge of a pond; C. punctatus, mainly wet soil between silage reserves; C. salinarius, algae; and C. stigma, algae and wet soil between silage reserves. We also recorded significantly higher densities of coprophilic larvae within pastures in cow dung located near forests, which is likely due to the localization of potential hosts; the presence of these larvae within cow dung is, however, uninfluenced by relative distance from farms. A better knowledge of the microhabitats of Culicoides biting midges and their spatial distribution may allow the development of targeted species-specific vector control strategies, and may help to prevent the creation of new larval development sites.
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Affiliation(s)
- Jean-Yves Zimmer
- Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liege, Passage des Déportés 2, B-5030 Gembloux, Belgium.
| | - Yves Brostaux
- Applied Statistics, Computer Science and Mathematics, Gembloux Agro-Bio Tech, University of Liege, Passage des Déportés 2, B-5030 Gembloux, Belgium
| | - Eric Haubruge
- Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liege, Passage des Déportés 2, B-5030 Gembloux, Belgium
| | - Frédéric Francis
- Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liege, Passage des Déportés 2, B-5030 Gembloux, Belgium
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Garros C, Balenghien T, Carpenter S, Delécolle JC, Meiswinkel R, Pédarrieu A, Rakotoarivony I, Gardès L, Golding N, Barber J, Miranda M, Borràs DB, Goffredo M, Monaco F, Pagès N, Sghaier S, Hammami S, Calvo JH, Lucientes J, Geysen D, De Deken G, Sarto I Monteys V, Schwenkenbecher J, Kampen H, Hoffmann B, Lehmann K, Werner D, Baldet T, Lancelot R, Cêtre-Sossah C. Towards the PCR-based identification of Palaearctic Culicoides biting midges (Diptera: Ceratopogonidae): results from an international ring trial targeting four species of the subgenus Avaritia. Parasit Vectors 2014; 7:223. [PMID: 24884950 PMCID: PMC4024274 DOI: 10.1186/1756-3305-7-223] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 04/28/2014] [Indexed: 01/11/2023] Open
Abstract
Background Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are biological vectors of internationally important arboviruses. To understand the role of Culicoides in the transmission of these viruses, it is essential to correctly identify the species involved. Within the western Palaearctic region, the main suspected vector species, C. obsoletus, C. scoticus, C. dewulfi and C. chiopterus, have similar wing patterns, which makes it difficult to separate and identify them correctly. Methods In this study, designed as an inter-laboratory ring trial with twelve partners from Europe and North Africa, we assess four PCR-based assays which are used routinely to differentiate the four species of Culicoides listed above. The assays based on mitochondrial or ribosomal DNA or microarray hybridisation were tested using aliquots of Culicoides DNA (extracted using commercial kits), crude lysates of ground specimens and whole Culicoides (265 individuals), and non-Culicoides Ceratopogonidae (13 individuals) collected from across Europe. Results A total of 800 molecular assays were implemented. The in-house assays functioned effectively, although specificity and sensitivity varied according to the molecular marker and DNA extraction method used. The Obsoletus group specificity was overall high (95-99%) while the sensitivity varied greatly (59.6-100%). DNA extraction methods impacted the sensitivity of the assays as well as the type of sample used as template for the DNA extraction. Conclusions The results are discussed in terms of current use of species diagnostic assays and the future development of molecular tools for the rapid differentiation of cryptic Culicoides species.
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Batten C, Darpel K, Henstock M, Fay P, Veronesi E, Gubbins S, Graves S, Frost L, Oura C. Evidence for transmission of bluetongue virus serotype 26 through direct contact. PLoS One 2014; 9:e96049. [PMID: 24797910 PMCID: PMC4010411 DOI: 10.1371/journal.pone.0096049] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 04/03/2014] [Indexed: 01/02/2023] Open
Abstract
The aim of this study was to assess the mechanisms of transmission of bluetongue virus serotype 26 (BTV-26) in goats. A previous study, which investigated the pathogenicity and infection kinetics of BTV-26 in goats, unexpectedly revealed that one control goat may have been infected through a direct contact transmission route. To investigate the transmission mechanisms of BTV-26 in more detail an experimental infection study was carried out in which three goats were infected with BTV-26, three goats were kept uninfected, but were housed in direct contact with the infected goats, and an additional four goats were kept in indirect contact separated from infected goats by metal gates. This barrier allowed the goats to have occasional face-to-face contact in the same airspace, but feeding, watering, sampling and environmental cleaning was carried out separately. The three experimentally infected goats did not show clinical signs of BTV, however high levels of viral RNA were detected and virus was isolated from their blood. At 21 dpi viral RNA was detected in, and virus was isolated from the blood of the three direct contact goats, which also seroconverted. The four indirect barrier contact goats remained uninfected throughout the duration of the experiment. In order to assess replication in a laboratory model species of Culicoides biting midge, more than 300 Culicoides sonorensis were fed a BTV-26 spiked blood meal and incubated for 7 days. The dissemination of BTV-26 in individual C. sonorensis was inferred from the quantity of virus RNA and indicated that none of the insects processed at day 7 possessed transmissible infections. This study shows that BTV-26 is easily transmitted through direct contact transmission between goats, and the strain does not seem to replicate in C. sonorensis midges using standard incubation conditions.
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Affiliation(s)
- Carrie Batten
- Non Vesicular Reference Laboratory, The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Karin Darpel
- Vaccinology, The Pirbright Institute, Woking, Surrey, United Kingdom
- School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Mark Henstock
- Non Vesicular Reference Laboratory, The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Petra Fay
- Non Vesicular Reference Laboratory, The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Eva Veronesi
- Entomology, The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Simon Gubbins
- Centre for Integrative Biology, The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Samantha Graves
- Non Vesicular Reference Laboratory, The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Lorraine Frost
- Non Vesicular Reference Laboratory, The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Christopher Oura
- Non Vesicular Reference Laboratory, The Pirbright Institute, Woking, Surrey, United Kingdom
- School of Veterinary Medicine, University of the West Indies, St. Augustine, Trinidad and Tobago
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Gubbins S, Turner J, Baylis M, van der Stede Y, van Schaik G, Abrahantes JC, Wilson AJ. Inferences about the transmission of Schmallenberg virus within and between farms. Prev Vet Med 2014; 116:380-90. [PMID: 24857371 PMCID: PMC4204990 DOI: 10.1016/j.prevetmed.2014.04.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 02/27/2014] [Accepted: 04/19/2014] [Indexed: 11/18/2022]
Abstract
In the summer of 2011 Schmallenberg virus (SBV), a Culicoides-borne orthobunyavirus, emerged in Germany and The Netherlands and subsequently spread across much of Europe. To draw inferences about the transmission of SBV we have developed two models to describe its spread within and between farms. The within-farm model was fitted to seroprevalence data for cattle and sheep farms in Belgium and The Netherlands, with parameters estimated using approximate Bayesian computation. Despite the short duration of viraemia in cattle and sheep (mean of 3–4 days) the within-farm seroprevalence can reach high levels (mean within-herd seroprevalence >80%), largely because the probability of transmission from host to vector is high (14%) and SBV is able to replicate quickly (0.03 per day-degree) and at relatively low temperatures (threshold for replication: 12.3 °C). Parameter estimates from the within-farm model were then used in a separate between-farm model to simulate the regional spread of SBV. This showed that the rapid spread of SBV at a regional level is primarily a consequence of the high probability of transmission from host to vector and the temperature requirements for virus replication. Our results, obtained for a region of the UK in a typical year with regard to animal movements, indicate that there is no need to invoke additional transmission mechanisms to explain the observed patterns of rapid spread of SBV in Europe. Moreover, the imposition of movement restrictions, even a total movement ban, has little effect on the spread of SBV at this scale.
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Affiliation(s)
- Simon Gubbins
- The Pirbright Institute, Ash Road, Pirbright, Surrey GU24 0NF, UK.
| | - Joanne Turner
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston, Cheshire CH64 7TE, UK
| | - Matthew Baylis
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston, Cheshire CH64 7TE, UK
| | - Yves van der Stede
- Unit of Co-ordination Veterinary Diagnosis-Epidemiology and Risk Assessment, CODA-CERVA, Groeselenberg 99, 1180 Brussels, Belgium; Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | | | | | - Anthony J Wilson
- The Pirbright Institute, Ash Road, Pirbright, Surrey GU24 0NF, UK
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Field trials assessing deltamethrin (Butox®) treatments of sheep against Culicoides species. Parasitol Res 2014; 113:2641-5. [DOI: 10.1007/s00436-014-3916-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2014] [Accepted: 04/11/2014] [Indexed: 10/25/2022]
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Balenghien T, Pagès N, Goffredo M, Carpenter S, Augot D, Jacquier E, Talavera S, Monaco F, Depaquit J, Grillet C, Pujols J, Satta G, Kasbari M, Setier-Rio ML, Izzo F, Alkan C, Delécolle JC, Quaglia M, Charrel R, Polci A, Bréard E, Federici V, Cêtre-Sossah C, Garros C. The emergence of Schmallenberg virus across Culicoides communities and ecosystems in Europe. Prev Vet Med 2014; 116:360-9. [PMID: 24698329 DOI: 10.1016/j.prevetmed.2014.03.007] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 01/24/2014] [Accepted: 03/08/2014] [Indexed: 12/27/2022]
Abstract
Schmallenberg virus (SBV), a novel arboviral pathogen, has emerged and spread across Europe since 2011 inflicting congenital deformities in the offspring of infected adult ruminants. Several species of Culicoides biting midges (Diptera: Ceratopogonidae) have been implicated in the transmission of SBV through studies conducted in northern Europe. In this study Culicoides from SBV outbreak areas of mainland France and Italy (Sardinia) were screened for viral RNA. The role of both C. obsoletus and the Obsoletus complex (C. obsoletus and C. scoticus) in transmission of SBV were confirmed in France and SBV was also discovered in a pool of C. nubeculosus for the first time, implicating this species as a potential vector. While collections in Sardinia were dominated by C. imicola, only relatively small quantities of SBV RNA were detected in pools of this species and conclusive evidence of its potential role in transmission is required. In addition to these field-based studies, infection rates in colony-derived individuals of C. nubeculosus and field-collected C. scoticus are also examined in the laboratory. Rates of infection in C. nubeculosus were low, confirming previous studies, while preliminary examination of C. scoticus demonstrated that while this species can replicate SBV to a potentially transmissible level, further work is required to fully define comparative competence between species in the region. Finally, the oral competence for SBV of two abundant and widespread mosquito vector species in the laboratory is assessed. Neither Aedes albopictus nor Culex pipiens were demonstrated to replicate SBV to transmissible levels and appear unlikely to play a major role in transmission. Other vector competence data produced from studies across Europe to date is then comprehensively reviewed and compared with that generated previously for bluetongue virus.
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Affiliation(s)
- Thomas Balenghien
- Cirad, UMR15 CMAEE, F-34398 Montpellier, France; INRA, UMR1309 CMAEE, F-34398 Montpellier, France.
| | - Nonito Pagès
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Spain
| | - Maria Goffredo
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Campo Boario, 64100 Teramo, Italy
| | - Simon Carpenter
- The Pirbright Institute, Ash Road, Woking, Surrey GU24 0NF, United Kingdom
| | - Denis Augot
- Université de Reims Champagne-Ardenne, ANSES, SFR Cap Santé, EA4688 - USC « VECPAR », Reims, France
| | - Elisabeth Jacquier
- Cirad, UMR15 CMAEE, F-34398 Montpellier, France; INRA, UMR1309 CMAEE, F-34398 Montpellier, France
| | - Sandra Talavera
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Spain
| | - Federica Monaco
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Campo Boario, 64100 Teramo, Italy
| | - Jérôme Depaquit
- Université de Reims Champagne-Ardenne, ANSES, SFR Cap Santé, EA4688 - USC « VECPAR », Reims, France
| | - Colette Grillet
- Cirad, UMR15 CMAEE, F-34398 Montpellier, France; INRA, UMR1309 CMAEE, F-34398 Montpellier, France
| | - Joan Pujols
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Spain
| | - Giuseppe Satta
- Istituto Zooprofilattico della Sardegna, Via Duca degli Abruzzi 8, Sardinia, Italy
| | - Mohamed Kasbari
- Université de Reims Champagne-Ardenne, ANSES, SFR Cap Santé, EA4688 - USC « VECPAR », Reims, France
| | | | - Francesca Izzo
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Campo Boario, 64100 Teramo, Italy
| | - Cigdem Alkan
- UMR_D 190 "Emergence des Pathologies Virales", Aix Marseille Univ, IRD French Institute of Research for Development, EHESP French School of Public Health, 13005 Marseille, France; IHU Mediterranee Infection, APHM Public Hospitals of Marseille, 13005 Marseille, France
| | | | - Michela Quaglia
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Campo Boario, 64100 Teramo, Italy
| | - Rémi Charrel
- UMR_D 190 "Emergence des Pathologies Virales", Aix Marseille Univ, IRD French Institute of Research for Development, EHESP French School of Public Health, 13005 Marseille, France; IHU Mediterranee Infection, APHM Public Hospitals of Marseille, 13005 Marseille, France
| | - Andrea Polci
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Campo Boario, 64100 Teramo, Italy
| | | | - Valentina Federici
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Campo Boario, 64100 Teramo, Italy
| | - Catherine Cêtre-Sossah
- Cirad, UMR15 CMAEE, F-34398 Montpellier, France; INRA, UMR1309 CMAEE, F-34398 Montpellier, France
| | - Claire Garros
- Cirad, UMR15 CMAEE, F-34398 Montpellier, France; INRA, UMR1309 CMAEE, F-34398 Montpellier, France
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Meiswinkel R, Scolamacchia F, Dik M, Mudde J, Dijkstra E, Van Der Ven IJK, Elbers ARW. The Mondrian matrix: Culicoides biting midge abundance and seasonal incidence during the 2006-2008 epidemic of bluetongue in the Netherlands. MEDICAL AND VETERINARY ENTOMOLOGY 2014; 28:10-20. [PMID: 23834350 DOI: 10.1111/mve.12013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 12/03/2012] [Accepted: 12/03/2012] [Indexed: 06/02/2023]
Abstract
During the northern Europe epidemic of bluetongue (BT), Onderstepoort-type blacklight traps were used to capture Culicoides Latreille (Diptera: Ceratopogonidae) biting midges weekly between November 2006 and December 2008 on 21 livestock farms in the Netherlands. Proven and potential vectors for the bluetongue virus (BTV) comprised almost 80% of the midges collected: the Obsoletus complex, constituting C. obsoletus (Meigen) and C. scoticus Downes & Kettle (44.2%), C. dewulfi Goetghebuer (16.4%), C. chiopterus (Meigen) (16.3%) and C. pulicaris (Linnaeus) (0.1%). Half of the 24 commonest species of Culicoides captured completed only one (univoltine) or two (bivoltine) generations annually, whereas multivoltine species (including all BTV vectors) cycled through five to six generations (exceeding the one to four generations calculated in earlier decades). Whether this increment signals a change in the phenology of northern Europe Culicoides or simply is an adaptive response that manifests during warmer episodes, thus heightening periodically the incursive potential of midge-borne arboviruses, remains to be clarified. Culicoides duddingstoni Kettle & Lawson, C. grisescens Edwards, C. maritimus Kieffer, C. pallidicornis Kieffer and C. riethi Kieffer are new records for the biting midge fauna of the Netherlands. It is suggested that C. punctatus (Meigen) be added to the European list of vector Culicoides.
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Affiliation(s)
- R Meiswinkel
- Department of Epidemiology, Crisis Organization and Diagnostics, Central Veterinary Institute, Part of Wageningen University and Research Centre, Lelystad, The Netherlands; National Plant Protection Organisation, Wageningen, The Netherlands
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Robin M, Archer D, Garros C, Gardès L, Baylis M. The threat of midge-borne equine disease: investigation of Culicoides species on UK equine premises. Vet Rec 2014; 174:301. [PMID: 24508765 DOI: 10.1136/vr.102151] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
There are concerns that outbreaks of exotic or novel vector-borne viral diseases will increasingly occur within northern Europe and the UK in the future. African horse sickness (AHS) is a viral disease of equids that is transmitted by Culicoides and is associated with up to 95 per cent mortality. AHS has never occurred in the UK; however, it has been suggested that appropriate Culicoides species and climatic conditions are present in northern Europe to support an outbreak. No data are currently available regarding the Culicoides species present on UK equine properties. This study demonstrates the presence of potential AHS virus vector Culicoides species on both urban and rural equine properties within the south-east UK. PCR analysis revealed that engorged members of these species contained equine DNA, proving a direct vector-host interaction. It is therefore possible that an AHS outbreak could occur in the UK if the virus were to be imported and, given the severe welfare and economic consequences of AHS, this would have devastating consequences to the naïve UK equine population.
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Affiliation(s)
- M Robin
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst, Chester High Road, Neston, Cheshire CH64 7TE
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De Regge N, Madder M, Deblauwe I, Losson B, Fassotte C, Demeulemeester J, Smeets F, Tomme M, Cay AB. Schmallenberg virus circulation in culicoides in Belgium in 2012: field validation of a real time RT-PCR approach to assess virus replication and dissemination in midges. PLoS One 2014; 9:e87005. [PMID: 24466312 PMCID: PMC3900700 DOI: 10.1371/journal.pone.0087005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 12/15/2013] [Indexed: 01/10/2023] Open
Abstract
Indigenous Culicoides biting midges are suggested to be putative vectors for the recently emerged Schmallenberg virus (SBV) based on SBV RNA detection in field-caught midges. Furthermore, SBV replication and dissemination has been evidenced in C. sonorensis under laboratory conditions. After SBV had been detected in Culicoides biting midges from Belgium in August 2011, it spread all over the country by the end of 2011, as evidenced by very high between-herd seroprevalence rates in sheep and cattle. This study investigated if a renewed SBV circulation in midges occurred in 2012 in the context of high seroprevalence in the animal host population and evaluated if a recently proposed realtime RT-PCR approach that is meant to allow assessing the vector competence of Culicoides for SBV and bluetongue virus under laboratory conditions was applicable to field-caught midges. Therefore midges caught with 12 OVI traps in four different regions in Belgium between May and November 2012, were morphologically identified, age graded, pooled and tested for the presence of SBV RNA by realtime RT-PCR. The results demonstrate that although no SBV could be detected in nulliparous midges caught in May 2012, a renewed but short lived circulation of SBV in parous midges belonging to the subgenus Avaritia occured in August 2012 at all four regions. The infection prevalence reached up to 2.86% in the south of Belgium, the region where a lower seroprevalence was found at the end of 2011 than in the rest of the country. Furthermore, a frequency analysis of the Ct values obtained for 31 SBV-S segment positive pools of Avaritia midges showed a clear bimodal distribution with peaks of Ct values between 21–24 and 33–36. This closely resembles the laboratory results obtained for SBV infection of C. sonorensis and implicates indigenous midges belonging to the subgenus Avaritia as competent vectors for SBV.
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Affiliation(s)
- Nick De Regge
- Operational Direction Viral Diseases, CODA-CERVA, Brussel, Belgium
- * E-mail:
| | - Maxime Madder
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
| | - Isra Deblauwe
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Bertrand Losson
- Department of Infectious and Parasitic Diseases, University of Liège, Liège, Belgium
| | - Christiane Fassotte
- Life Science Department, Walloon Agricultural Research Center (CRA-W), Gembloux, Belgium
| | - Julie Demeulemeester
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - François Smeets
- Department of Infectious and Parasitic Diseases, University of Liège, Liège, Belgium
| | - Marie Tomme
- Life Science Department, Walloon Agricultural Research Center (CRA-W), Gembloux, Belgium
| | - Ann Brigitte Cay
- Operational Direction Viral Diseases, CODA-CERVA, Brussel, Belgium
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Ayllón T, Nijhof AM, Weiher W, Bauer B, Allène X, Clausen PH. Feeding behaviour of Culicoides spp. (Diptera: Ceratopogonidae) on cattle and sheep in northeast Germany. Parasit Vectors 2014; 7:34. [PMID: 24438698 PMCID: PMC3896851 DOI: 10.1186/1756-3305-7-34] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 01/12/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Culicoides spp. play an important role in the transmission of several vector-borne pathogens such as Bluetongue and Schmallenberg virus in Europe. To better understand the biology of local Culicoides species, a study divided into three parts was performed in northeast Germany to elucidate the feeding activity patterns (study A), preferential landing and feeding sites (study B) and host feeding preferences (study C) of Culicoides spp. using cattle and sheep as baits. METHODS In study A, the activity of Culicoides spp. was monitored over a 72 h period by collecting insects at regular intervals from the interior of drop traps with cattle or sheep standing inside. In study B, Culicoides spp. were directly aspirated from the coat and fleece of cattle and sheep during the peak activity period of Culicoides. In study C, Culicoides spp. were collected using drop traps with either cattle or sheep standing inside and located 10 m apart. RESULTS In study A, 3,545 Culicoides midges belonging to 13 species were collected, peak activity was observed at sunset. In study B, 2,024 Culicoides midges were collected. A significantly higher number of midges was collected from the belly and flank of cattle in comparison to their head region. In study C, 3,710 Culicoides midges were collected; 3,077 (83%) originated from cattle and 633 (17%) from sheep. Nearly half (46.7%) of the midges collected from cattle were engorged, significantly more than the number of engorged midges collected from sheep (7.5%). Culicoides from the Obsoletus complex (C. obsoletus and C. scoticus) were the most common Culicoides species encountered, followed by C. punctatus. Other species identified were C. dewulfi, C. chiopterus, C. pulicaris, C. lupicaris, C. pallidicornis, C. subfascipennis, C. achrayi, C. stigma, C. griseidorsum and C. subfagineus, the last two species are reported for the first time in Germany. Engorged C. chiopterus were collected in relatively high numbers from sheep, suggesting that this species may have a preference for sheep. CONCLUSIONS An insight into the feeding behaviour of local Culicoides species under field conditions in northeast Germany was obtained, with implications for the implementation of control measures and midge-borne disease risk analysis.
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Affiliation(s)
| | | | | | | | | | - Peter-Henning Clausen
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str, 7-13, D 14163 Berlin, Germany.
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Harrup LE, Purse BV, Golding N, Mellor PS, Carpenter S. Larval development and emergence sites of farm-associated Culicoides in the United Kingdom. MEDICAL AND VETERINARY ENTOMOLOGY 2013; 27:441-449. [PMID: 23458570 DOI: 10.1111/mve.12006] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 09/11/2012] [Accepted: 10/26/2012] [Indexed: 06/01/2023]
Abstract
Culicoides biting midges (Diptera: Ceratopogonidae) are the biological vectors of internationally important arboviruses of livestock including bluetongue virus (BTV). Information on the habitats used by Culicoides for larval development is valuable for establishing targeted vector control strategies and for improving local scale models of vector abundance. This study combines emergence trap collections of adult Culicoides identified using molecular markers and physiochemical measurements of habitats to investigate larval development sites of Palaearctic Culicoides in South East England. The known range of larval habitats for several Culicoides species is extended and the potential BTV vector species C. obsoletus and C. scoticus are confirmed to co-occur in many larval habitats. The presence of emerging C. obsoletus was favoured by increasing substrate moisture level [odds ratio (OR) 6.94 (2.30; 20.90)] and substrate pH [OR 4.80 (1.66; 13.90)] [bias-corrected Dxy : 0.68; area under the curve (AUC): 0.86] rather than any particular larval habitat type, as expected for a species with relatively wide larval habitat preference. Of the newly emerged sub-genus Avaritia individuals collected, 23% were observed to have a degree of abdominal pigmentation commonly inferred to indicate parity. If consistent across species and locations, this observation represents a potential source of error for age structure analyses of Culicoides populations.
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Affiliation(s)
- L E Harrup
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, U.K.; Department of Zoology, University of Oxford, Oxford, U.K
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Rasmussen LD, Kirkeby C, Bødker R, Kristensen B, Rasmussen TB, Belsham GJ, Bøtner A. Rapid spread of Schmallenberg virus-infected biting midges (Culicoides spp.) across Denmark in 2012. Transbound Emerg Dis 2013; 61:12-6. [PMID: 24219171 DOI: 10.1111/tbed.12189] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Indexed: 11/28/2022]
Abstract
Detection of Schmallenberg virus RNA, using real-time RT-PCR, in biting midges (Culicoides spp.) caught at 48 locations in 2011 and four well-separated farms during 2012 in Denmark, revealed a remarkably rapid spread of virus-infected midges across the country. During 2012, some 213 pools of obsoletus group midges (10 specimens per pool) were examined, and of these, 35 of the 174 parous pools were Schmallenberg virus RNA positive and 11 of them were positive in the heads. Culicoides species-specific PCRs identified both C. obsoletus and C. dewulfi as vectors of Schmallenberg virus.
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Affiliation(s)
- L D Rasmussen
- National Veterinary Institute, Technical University of Denmark, Kalvehave, Denmark
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Veronesi E, Antony F, Gubbins S, Golding N, Blackwell A, Mertens PPC, Brownlie J, Darpel KE, Mellor PS, Carpenter S. Measurement of the infection and dissemination of bluetongue virus in culicoides biting midges using a semi-quantitative rt-PCR assay and isolation of infectious virus. PLoS One 2013; 8:e70800. [PMID: 23940643 PMCID: PMC3733650 DOI: 10.1371/journal.pone.0070800] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 06/24/2013] [Indexed: 11/20/2022] Open
Abstract
Background Culicoides biting midges (Diptera: Ceratopogonidae) are the biological vectors of globally significant arboviruses of livestock including bluetongue virus (BTV), African horse sickness virus (AHSV) and the recently emerging Schmallenberg virus (SBV). From 2006–2009 outbreaks of BTV in northern Europe inflicted major disruption and economic losses to farmers and several attempts were made to implicate Palaearctic Culicoides species as vectors. Results from these studies were difficult to interpret as they used semi-quantitative RT-PCR (sqPCR) assays as the major diagnostic tool, a technique that had not been validated for use in this role. In this study we validate the use of these assays by carrying out time-series detection of BTV RNA in two colony species of Culicoides and compare the results with the more traditional isolation of infectious BTV on cell culture. Methodology/Principal Findings A BTV serotype 1 strain mixed with horse blood was fed to several hundred individuals of Culicoides sonorensis (Wirth & Jones) and C. nubeculosus (Mg.) using a membrane-based assay and replete individuals were then incubated at 25°C. At daily intervals 25 Culicoides of each species were removed from incubation, homogenised and BTV quantified in each individual using sqPCR (Cq values) and virus isolation on a KC-C. sonorensis embryonic cell line, followed by antigen enzyme-linked immunosorbent assay (ELISA). In addition, comparisons were also drawn between the results obtained with whole C. sonorensis and with individually dissected individuals to determine the level of BTV dissemination. Conclusions/Significance Cq values generated from time-series infection experiments in both C. sonorensis and C. nubeculosus confirmed previous studies that relied upon the isolation and detection of infectious BTV. Implications on the testing of field-collected Culicoides as potential virus vectors by PCR assays and the use of such assays as front-line tools for use in diagnostic laboratories in this role are discussed.
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Affiliation(s)
- Eva Veronesi
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | - Frank Antony
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | - Simon Gubbins
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | - Nick Golding
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | | | - Peter PC. Mertens
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | - Joe Brownlie
- Royal Veterinary College, Hatfield, Herts, United Kingdom
| | - Karin E. Darpel
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
- University of Surrey, Guildford, Surrey, United Kingdom
| | - Philip S. Mellor
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | - Simon Carpenter
- Vector-borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Surrey, United Kingdom
- * E-mail:
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