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Teo EJM, Apanaskevich DA, Barker SC, Nakao R. Dermacentor (Indocentor) auratus Supino 1897: Potential geographic range, and medical and veterinary significance. Acta Trop 2024; 254:107197. [PMID: 38554993 DOI: 10.1016/j.actatropica.2024.107197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 03/05/2024] [Accepted: 03/21/2024] [Indexed: 04/02/2024]
Abstract
Dermacentor (Indocentor) auratus Supino, 1897 occurs in many regions of Southeast Asia and South Asia. In many regions of Southeast Asia and South Asia, targeted tick sampling and subsequent screening of collected D. auratus ticks have detected pathogenic bacteria and viruses in D. auratus. These disease-causing pathogens that have been detected in D. auratus include Anaplasma, Bartonella, Borrelia, Rickettsia (including spotted fever group rickettsiae), African swine fever virus, Lanjan virus, and Kyasanur forest disease virus. Although D. auratus predominantly infests wild pigs, this tick is also an occasional parasite of humans and other animals. Indeed, some 91 % of human otoacariasis cases in Sri Lanka were due to infestation by D. auratus. With the propensity of this tick to feed on multiple species of hosts, including humans, and the detection of pathogenic bacteria and viruses from this tick, D. auratus is a tick of medical, veterinary, and indeed zoonotic concern. The geographic range of this tick, however, is not well known. Therefore, in the present paper, we used the species distribution model, BIOCLIM, to project the potential geographic range of D. auratus, which may aid pathogen and tick-vector surveillance. We showed that the potential geographic range of D. auratus is far wider than the current geographic distribution of this tick, and that regions in Africa, and in North and South America seem to have suitable climates for D. auratus. Interestingly, in Southeast Asia, Borneo and Philippines also have suitable climates for D. auratus, but D. auratus has not been found in these regions yet despite the apparent close proximity of these regions to Mainland Southeast Asia, where D. auratus occurs. We thus hypothesize that the geographic distribution of D. auratus is largely dependent on the movement of wild pigs and whether or not these wild pigs are able to overcome dispersal barriers. We also review the potential pathogens and the diseases that may be associated with D. auratus and provide an updated host index for this tick.
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Affiliation(s)
- Ernest J M Teo
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan.
| | - Dmitry A Apanaskevich
- United States National Tick Collection, The James H. Oliver, Jr. Institute for Coastal Plain Science, Georgia Southern University, Statesboro, GA 30460, USA; Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA
| | - Stephen C Barker
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, Qld 4072, Australia
| | - Ryo Nakao
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
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Juszkiewicz M, Walczak M, Woźniakowski G, Podgórska K. African Swine Fever: Transmission, Spread, and Control through Biosecurity and Disinfection, Including Polish Trends. Viruses 2023; 15:2275. [PMID: 38005951 PMCID: PMC10674562 DOI: 10.3390/v15112275] [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: 09/12/2023] [Revised: 10/11/2023] [Accepted: 11/17/2023] [Indexed: 11/26/2023] Open
Abstract
African swine fever is a contagious disease, affecting pigs and wild boars, which poses a major threat to the pig industry worldwide and, therefore, to the agricultural economies of many countries. Despite intensive studies, an effective vaccine against the disease has not yet been developed. Since 2007, ASFV has been circulating in Eastern and Central Europe, covering an increasingly large area. As of 2018, the disease is additionally spreading at an unprecedented scale in Southeast Asia, nearly ruining China's pig-producing sector and generating economic losses of approximately USD 111.2 billion in 2019. ASFV's high resistance to environmental conditions, together with the lack of an approved vaccine, plays a key role in the spread of the disease. Therefore, the biosecurity and disinfection of pig farms are the only effective tools through which to prevent ASFV from entering the farms. The selection of a disinfectant, with research-proven efficacy and proper use, taking into account environmental conditions, exposure time, pH range, and temperature, plays a crucial role in the disinfection process. Despite the significant importance of ASF epizootics, little information is available on the effectiveness of different disinfectants against ASFV. In this review, we have compiled the current knowledge on the transmission, spread, and control of ASF using the principles of biosecurity, with particular attention to disinfection, including a perspective based on Polish experience with ASF control.
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Affiliation(s)
- Małgorzata Juszkiewicz
- Department of Swine Diseases, National Veterinary Research Institute, Partyzantów 57 Avenue, 24-100 Puławy, Poland; (M.W.); (K.P.)
| | - Marek Walczak
- Department of Swine Diseases, National Veterinary Research Institute, Partyzantów 57 Avenue, 24-100 Puławy, Poland; (M.W.); (K.P.)
| | - Grzegorz Woźniakowski
- Department of Diagnostics and Clinical Sciences, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, Lwowska 1 Street, 87-100 Toruń, Poland;
| | - Katarzyna Podgórska
- Department of Swine Diseases, National Veterinary Research Institute, Partyzantów 57 Avenue, 24-100 Puławy, Poland; (M.W.); (K.P.)
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Rogoll L, Güttner AK, Schulz K, Bergmann H, Staubach C, Conraths FJ, Sauter-Louis C. Seasonal Occurrence of African Swine Fever in Wild Boar and Domestic Pigs in EU Member States. Viruses 2023; 15:1955. [PMID: 37766361 PMCID: PMC10536336 DOI: 10.3390/v15091955] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/14/2023] [Accepted: 09/19/2023] [Indexed: 09/29/2023] Open
Abstract
Since 2007, African swine fever (ASF) has spread widely within Europe and beyond. Most affected countries recorded outbreaks in domestic pigs and cases in wild boar. Outbreak data from 2014 to 2021 were used to investigate the seasonal pattern of ASF in domestic pigs and wild boar across affected member states of the European Union, since knowledge of seasonal patterns may provide the potential to adapt prevention, surveillance and control during times of increased risk. In domestic pigs, a yearly peak was observed in many European countries in summer (predominantly in July and August). In wild boar, the patterns showed more variability. In many countries, there was a seasonal peak of ASF occurrence in winter (predominantly in January and December), with an additional summer peak in the Baltic States (predominantly in July) and a further spring peak in Poland (predominantly in March). The observed seasonal effects may be related to the abundance and population dynamics of wild boar and to seasonality in pig farming. Moreover, ASF occurrence may also be influenced by human activities in both domestic pigs and wild boar.
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Affiliation(s)
- Lisa Rogoll
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (A.-K.G.); (K.S.); (H.B.); (C.S.); (F.J.C.); (C.S.-L.)
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4
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Lv T, Xie X, Song N, Zhang S, Ding Y, Liu K, Diao L, Chen X, Jiang S, Li T, Zhang W, Cao Y. Expounding the role of tick in Africa swine fever virus transmission and seeking effective prevention measures: A review. Front Immunol 2022; 13:1093599. [PMID: 36591310 PMCID: PMC9800779 DOI: 10.3389/fimmu.2022.1093599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
African swine fever (ASF), a highly contagious, deadly infectious disease, has caused huge economic losses to animal husbandry with a 100% mortality rate of the most acute and acute infection, which is listed as a legally reported animal disease by the World Organization for Animal Health (OIE). African swine fever virus (ASFV) is the causative agent of ASF, which is the only member of the Asfarviridae family. Ornithodoros soft ticks play an important role in ASFV transmission by active biological or mechanical transmission or by passive transport or ingestion, particularly in Africa, Europe, and the United States. First, this review summarized recent reports on (1) tick species capable of transmitting ASFV, (2) the importance of ticks in the transmission and epidemiological cycle of ASFV, and (3) the ASFV strains of tick transmission, to provide a detailed description of tick-borne ASFV. Second, the dynamics of tick infection with ASFV and the tick-induced immune suppression were further elaborated to explain how ticks spread ASFV. Third, the development of the anti-tick vaccine was summarized, and the prospect of the anti-tick vaccine was recapitulated. Then, the marked attenuated vaccine, ASFV-G-ΔI177L, was compared with those of the anti-tick vaccine to represent potential therapeutic or strategies to combat ASF.
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Affiliation(s)
- Tianbao Lv
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xufeng Xie
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Ning Song
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shilei Zhang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yue Ding
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Kun Liu
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Luteng Diao
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xi Chen
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shuang Jiang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Tiger Li
- Portsmouth Abbey School, Portsmouth, RI, United States
| | - Wenlong Zhang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China,Key Laboratory for Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China,*Correspondence: Yongguo Cao, ; Wenlong Zhang,
| | - Yongguo Cao
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China,Key Laboratory for Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China,*Correspondence: Yongguo Cao, ; Wenlong Zhang,
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5
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African swine fever virus: A raised global upsurge and a continuous threaten to pig husbandry. Microb Pathog 2022; 167:105561. [DOI: 10.1016/j.micpath.2022.105561] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 04/01/2022] [Accepted: 04/27/2022] [Indexed: 11/21/2022]
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Pereira De Oliveira R, Vial L, Le Potier MF. Quantification of ASFV DNA and RNA in Ornithodoros Soft Ticks. Methods Mol Biol 2022; 2503:105-118. [PMID: 35575889 DOI: 10.1007/978-1-0716-2333-6_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Molecular biology methods are highly sensitive to detect the genome of pathogens and to study their biology. Polymerase chain reaction (PCR) and reverse transcription followed by a polymerase chain reaction (RT-PCR) permit the detection of the presence and the replication of African swine fever virus in soft ticks. Here, we described our techniques to detect and quantify DNA and RNA of African swine fever virus in soft ticks including a housekeeping gene of soft ticks as internal control.
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Affiliation(s)
- Rémi Pereira De Oliveira
- UMR Animal, Santé, Territoires, Risque et Ecosystèmes (ASTRE), CIRAD-INRAE-Université de Montpellier, Montpellier, France.
- Laboratoire de Ploufragan/Plouzané/Niort, ANSES, Ploufragan, France.
| | - Laurence Vial
- UMR Animal, Santé, Territoires, Risque et Ecosystèmes (ASTRE), CIRAD-INRAE-Université de Montpellier, Montpellier, France
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Wang J, Ji M, Yuan B, Luo A, Jiang Z, Zhu T, Liu Y, Kamau PM, Jin L, Lai R. Peptide OPTX-1 From Ornithodoros papillipes Tick Inhibits the pS273R Protease of African Swine Fever Virus. Front Microbiol 2021; 12:778309. [PMID: 34925282 PMCID: PMC8678048 DOI: 10.3389/fmicb.2021.778309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 11/12/2021] [Indexed: 11/22/2022] Open
Abstract
African swine fever virus (ASFV) is a large double-stranded DNA virus and causes high mortality in swine. ASFV can be transmitted by biological vectors, including soft ticks in genus Ornithodoros but not hard ticks. However, the underlying mechanisms evolved in the vectorial capacity of soft ticks are not well-understood. Here, we found that a defensin-like peptide toxin OPTX-1 identified from Ornithodoros papillipes inhibits the enzyme activity of the ASFV pS273R protease with a Ki =0.821±0.526μM and shows inhibitory activity on the replication of ASFV. The analogs of OPTX-1 from hard ticks show more inhibitory efficient on pS273R protease. Considering that ticks are blood-sucking animals, we tested the effects of OPTX-1 and its analogs on the coagulation system. At last, top 3D structures represented surface analyses of the binding sites of pS273R with different inhibitors that were obtained by molecular docking based on known structural information. In summary, our study provides evidence that different inhibitory efficiencies between soft tick-derived OPTX-1 and hard tick-derived defensin-like peptides may determine the vector and reservoir competence of ticks.
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Affiliation(s)
- Jingjing Wang
- School of Life Sciences, University of Science and Technology of China, Hefei, China
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Mengyao Ji
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Bingqian Yuan
- School of Life Sciences, Tianjin University, Tianjin, China
| | - Anna Luo
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Zhenyuan Jiang
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Tengyu Zhu
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Yang Liu
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Peter Muiruri Kamau
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Lin Jin
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Ren Lai
- School of Life Sciences, University of Science and Technology of China, Hefei, China
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center, and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- School of Life Sciences, Tianjin University, Tianjin, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
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African Swine Fever Virus as a Difficult Opponent in the Fight for a Vaccine-Current Data. Viruses 2021; 13:v13071212. [PMID: 34201761 PMCID: PMC8310326 DOI: 10.3390/v13071212] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/17/2021] [Accepted: 06/19/2021] [Indexed: 12/13/2022] Open
Abstract
Prevention and control of African swine fever virus (ASFV) in Europe, Asia, and Africa seem to be extremely difficult in view of the ease with which it spreads, its high resistance to environmental conditions, and the many obstacles related to the introduction of effective specific immunoprophylaxis. Biological properties of ASFV indicate that the African swine fever (ASF) pandemic will continue to develop and that only the implementation of an effective and safe vaccine will ensure a reduction in the spread of ASFV. At present, vaccines against ASF are not available. The latest approaches to the ASFV vaccine’s design concentrate on the development of either modified live vaccines by targeted gene deletion from different isolates or subunit vaccines. The construction of an effective vaccine is hindered by the complex structure of the virus, the lack of an effective continuous cell line for the isolation and propagation of ASFV, unpredictable and stain-specific phenotypes after the genetic modification of ASFV, a risk of reversion to virulence, and our current inability to differentiate infected animals from vaccinated ones. Moreover, the design of vaccines intended for wild boars and oral administration is desirable. Despite several obstacles, the design of a safe and effective vaccine against ASFV seems to be achievable.
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Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Depner K, Drewe JA, Garin‐Bastuji B, Gonzales Rojas JL, Schmidt C, Herskin M, Michel V, Pasquali P, Roberts HC, Sihvonen LH, Spoolder H, Stahl K, Velarde A, Winckler C, Blome S, Boklund A, Bøtner A, Dhollander S, Rapagnà C, Van der Stede Y, Miranda Chueca MA. Research priorities to fill knowledge gaps in the control of African swine fever: possible transmission of African swine fever virus by vectors. EFSA J 2021; 19:e06676. [PMID: 34188718 PMCID: PMC8215588 DOI: 10.2903/j.efsa.2021.6676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The European Commission requested that EFSA provide study designs for the investigation of four research domains according to major gaps in knowledge identified by EFSA in a report published in 2019: (i) the patterns of seasonality of African Swine Fever (ASF) in wild boar and domestic pigs in the EU; (ii) the epidemiology of ASF in wild boar; (iii) survival of ASF virus (ASFV) in the environment and (iv) transmission of ASFV by vectors. In this Scientific Opinion, the fourth research domain on ASFV transmission by vectors is addressed. Eleven research objectives were proposed by the EFSA working group and broader ASF expert networks, such as ASF stop, ENETWILD, VectorNet, AHAW network and the AHAW Panel Experts. Of the 11 research objectives, six were prioritised based on the following set of criteria: (1) the impact on ASF management; (2) the feasibility or practicality to carry out the study; (3) the potential implementation of study results in practice; (4) a possible short time-frame study (< 1 year); (5) the novelty of the study and (6) if it was a priority for risk managers. The prioritised research objectives were: (I) Studies on the potential vector fauna at the pig-wild boar interface and the feeding preference of blood-feeding potential vectors in ASF-affected areas; (II) Assessment of the efficacy of insect screens on indoor/outdoor pig holdings to prevent the entry of blood-sucking vectors (i.e. Stomoxys) in ASF endemic areas; (III) Assess the role of mechanical vectors in the virus transmission in ASF-affected areas; (IV) Distribution of the potential mechanical transmission vectors in ASF-affected areas of the EU; (V) ASFV transmission by synanthropic birds; and (VI) Assessment on the presence/absence of the soft tick Ornithodoros erraticus in ASF-affected areas in Europe. For each of the selected research objectives, a research protocol has been proposed considering the potential impact on ASF management and the period of 1 year for the research activities.
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Artificial Feeding of All Consecutive Life Stages of Ixodes ricinus. Vaccines (Basel) 2021; 9:vaccines9040385. [PMID: 33919961 PMCID: PMC8070929 DOI: 10.3390/vaccines9040385] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/08/2021] [Accepted: 04/10/2021] [Indexed: 01/19/2023] Open
Abstract
The hard tick Ixodes ricinus is an obligate hematophagous arthropod and the main vector for several zoonotic diseases. The life cycle of this three-host tick species was completed for the first time in vitro by feeding all consecutive life stages using an artificial tick feeding system (ATFS) on heparinized bovine blood supplemented with glucose, adenosine triphosphate, and gentamicin. Relevant physiological parameters were compared to ticks fed on cattle (in vivo). All in vitro feedings lasted significantly longer and the mean engorgement weight of F0 adults and F1 larvae and nymphs was significantly lower compared to ticks fed in vivo. The proportions of engorged ticks were significantly lower for in vitro fed adults and nymphs as well, but higher for in vitro fed larvae. F1-females fed on blood supplemented with vitamin B had a higher detachment proportion and engorgement weight compared to F1-females fed on blood without vitamin B, suggesting that vitamin B supplementation is essential in the artificial feeding of I. ricinus ticks previously exposed to gentamicin.
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11
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Mauroy A, Depoorter P, Saegerman C, Cay B, De Regge N, Filippitzi ME, Fischer C, Laitat M, Maes D, Morelle K, Nauwynck H, Simons X, van den Berg T, Van Huffel X, Thiry E, Dewulf J. Semi-quantitative risk assessment by expert elicitation of potential introduction routes of African swine fever from wild reservoir to domestic pig industry and subsequent spread during the Belgian outbreak (2018-2019). Transbound Emerg Dis 2021; 68:2761-2773. [PMID: 33713549 DOI: 10.1111/tbed.14067] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 01/29/2021] [Accepted: 03/08/2021] [Indexed: 12/01/2022]
Abstract
Since the introduction in Georgia in 2007 of an African swine fever (ASF) genotype 2 virus strain, the virus has rapidly spread to both Western European and Asian countries. It now constitutes a major threat for the global swine industry. The ongoing European transmission cycle has been related to the 'wild boar habitat' with closed transmission events between wild boar populations and incidental spillovers to commercial and non-commercial (backyard) pig holdings. During the epidemic in Belgium, only wild boar were infected and although the introduction route has not yet been elucidated, the 'human factor' is highly suspected. While ASF was successfully contained in a small region in the Southern part of Belgium without affecting domestic pigs, the risk of spillover at the wild/domestic interface remains poorly assessed. In this study, we used a semi-quantitative method, involving national and international experts, to assess the risk associated with different transmission routes for ASF introduction from wild boar to domestic pig holdings and subsequent dissemination between holdings in the Belgian epidemiological context. Qualitative responses obtained by our questionnaire were numerically transformed and statistically processed to provide a semi-quantitative assessment of the occurrence of the hazard and a ranking of all transmission routes. 'Farmer', 'bedding material', 'veterinarian' and 'professionals from the pig sector' were considered as the most important transmission routes for ASF introduction from the wild reservoir to pig holdings. 'Animal movements', 'farmer', 'veterinarian', 'iatrogenic', 'animal transport truck' and 'animal care equipment' were considered as the most important transmission routes posing a risk of ASF spread between pig holdings. Combined with specific biosecurity checks in the holdings, this assessment helps in prioritizing risk mitigation measures against ASF introduction and further spread in the domestic pig industry, particularly while the ASF situation in Western Europe is worsening.
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Affiliation(s)
- Axel Mauroy
- Staff Direction for Risk Assessment, Directorate General Control Policy, Federal Agency for the Safety of the Food Chain, Bruxelles, Belgium
| | - Pieter Depoorter
- Staff Direction for Risk Assessment, Directorate General Control Policy, Federal Agency for the Safety of the Food Chain, Bruxelles, Belgium
| | - Claude Saegerman
- Faculty of Veterinary Medicine, Research Unit in Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULiège), Fundamental and Applied Research for Animal Health (FARAH) Centre, University of Liège, Liège, Belgium
| | - Brigitte Cay
- Service of Enzootic, Vector-Borne and Bee Diseases, Scientific Direction Infectious Diseases in Animals, Sciensano, Brussels, Belgium
| | - Nick De Regge
- Service of Enzootic, Vector-Borne and Bee Diseases, Scientific Direction Infectious Diseases in Animals, Sciensano, Brussels, Belgium
| | - Maria-Eleni Filippitzi
- Veterinary Epidemiology Unit, Department of Epidemiology and Public Health, Sciensano, Brussels, Belgium
| | - Claude Fischer
- Dept. Nature Management, University of Applied Sciences of Western Switzerland, Geneva, Switzerland
| | - Martine Laitat
- Faculty of Veterinary Medicine, Swine Clinic, Clinical Department of Production Animals, University of Liège, Liège, Belgium
| | - Dominiek Maes
- Faculty of Veterinary Medicine, Department of Reproduction, Obstetrics and Herd Health, Ghent University, Merelbeke, Belgium
| | - Kevin Morelle
- Faculty of Forestry and Wood Sciences, Department of Game Management and Wildlife Biology, Czech University of Life Sciences, Prague, Czech Republic.,Department of Migration, Max Planck Institute of Animal Behavior, Radolfzell, Germany
| | - Hans Nauwynck
- Faculty of Veterinary Medicine, Department of Virology, Parasitology and Immunology, Ghent University, Merelbeke, Belgium
| | - Xavier Simons
- Veterinary Epidemiology Unit, Department of Epidemiology and Public Health, Sciensano, Brussels, Belgium
| | | | - Xavier Van Huffel
- Staff Direction for Risk Assessment, Directorate General Control Policy, Federal Agency for the Safety of the Food Chain, Bruxelles, Belgium
| | - Etienne Thiry
- Faculty of Veterinary Medicine, Veterinary Virology, FARAH Centre, University of Liège, Liège, Belgium
| | - Jeroen Dewulf
- Faculty of Veterinary Medicine, Department of Reproduction, Obstetrics and Herd Health, Ghent University, Merelbeke, Belgium
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12
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Herm R, Kirik H, Vilem A, Zani L, Forth JH, Müller A, Michelitsch A, Wernike K, Werner D, Tummeleht L, Kampen H, Viltrop A. No evidence for African swine fever virus DNA in haematophagous arthropods collected at wild boar baiting sites in Estonia. Transbound Emerg Dis 2021; 68:2696-2702. [PMID: 33527715 DOI: 10.1111/tbed.14013] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/25/2021] [Accepted: 01/27/2021] [Indexed: 11/29/2022]
Abstract
African swine fever (ASF) is a highly pathogenic viral disease affecting all Suidae, with Ornithodoros moubata complex soft ticks acting as the biological arthropod vectors of the causative agent, African swine fever virus (ASFV). While ASFV is also transmissible via direct contact, pig products and fomites, other arthropods may be involved in virus transmission and persistence. Therefore, we checked various groups of blood-feeding arthropods collected during summer 2017 in wild boar habitats on the Estonian Island of Saaremaa for the presence of ASFV. Saaremaa had the highest ASF infection prevalences in Estonia in 2017, with an incidence of 9% among hunted wild boar. In addition to ASFV, we tested for other selected pathogens. In total, 784 ticks, 6,274 culicoid biting midges, 77 tabanids and 757 mosquitoes were tested as individuals or pools. No ASFV-DNA was found in any of them although about 20% of the tick samples tested positive for swine DNA. By contrast, tick-borne encephalitis virus-RNA was detected in one out of 37 tick pools (2.7%) and Borrelia burgdorferi s.l.-DNA in 20 individual ticks and 17 tick pools (25.2% of all samples). No Schmallenberg virus was detected in the Culicoides specimens. In conclusion, we found no evidence for Ixodes ricinus ticks, Culicoides punctatus and Obsoletus complex biting midges, Aedes spp., Anopheles spp. and Culiseta annulata mosquitoes, and Haematopota pluvialis tabanids playing a role in ASFV transmission in the wild boar population in Estonia.
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Affiliation(s)
- Reet Herm
- Chair of Veterinary Bio- and Population Medicine, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Tartu, Estonia
| | - Heli Kirik
- Chair of Biodiversity and Nature Tourism, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Tartu, Estonia
| | | | - Laura Zani
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Greifswald, Germany
| | - Jan Hendrik Forth
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Greifswald, Germany
| | - Alexandra Müller
- Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - Anna Michelitsch
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Greifswald, Germany
| | - Kerstin Wernike
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Greifswald, Germany
| | - Doreen Werner
- Leibniz Centre for Agricultural Landscape Research, Müncheberg, Germany
| | - Lea Tummeleht
- Chair of Veterinary Bio- and Population Medicine, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Tartu, Estonia
| | - Helge Kampen
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Greifswald, Germany
| | - Arvo Viltrop
- Chair of Veterinary Bio- and Population Medicine, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Tartu, Estonia
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13
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González J, Bickerton M, Toledo A. Applications of artificial membrane feeding for ixodid ticks. Acta Trop 2021; 215:105818. [PMID: 33406442 DOI: 10.1016/j.actatropica.2020.105818] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 12/23/2020] [Accepted: 12/24/2020] [Indexed: 11/18/2022]
Abstract
Ticks are obligatory hematophagous ectoparasites that feed on a large variety of vertebrates. In the laboratory, animals (mainly mice and rabbits) are used to maintain tick colonies. However, the use of animals to rear ticks can be expensive and requires dedicated animal facilities. In addition, research institutions are committed to the principle of 3Rs (Replacement, Reduction and Refinement), which encourages the use of alternatives to animals when possible. The development of artificial membrane systems has provided an alternative to animals, at least for some tick species. Over the years, different modifications in artificial feeding systems have led to new applications, including acaricide testing, tick-pathogen interaction, and novel approaches to study tick physiology. Although artificial membrane feeding still has some limitations, the method can provide numerous advantages, including the standardization of acaricide treatments under controlled conditions, an alternative to animals for tick rearing, and reduction of cost associated with animals and animal housing facilities. In this review, we summarized the evolution of tick feeding membranes and their applications over time, explaining the modifications incorporated to study tick physiology, tick-pathogen interactions, and acaricide testing.
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Affiliation(s)
- Julia González
- Center for Vector Biology, Department of Entomology, Rutgers University, 180 Jones Ave, New Brunswick, NJ 08901, USA
| | - Mathew Bickerton
- Center for Vector Biology, Department of Entomology, Rutgers University, 180 Jones Ave, New Brunswick, NJ 08901, USA; Bergen County Department of Health, Division of Environmental Health, 220 East Ridgewood Avenue, Paramus, NJ 07652, USA
| | - Alvaro Toledo
- Center for Vector Biology, Department of Entomology, Rutgers University, 180 Jones Ave, New Brunswick, NJ 08901, USA.
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14
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Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Depner K, Drewe JA, Garin‐Bastuji B, Gonzales Rojas JL, Gortazar Schmidt C, Herskin M, Michel V, Miranda Chueca MÁ, Pasquali P, Roberts HC, Sihvonen LH, Spoolder H, Stahl K, Velarde A, Winckler C, Abrahantes JC, Dhollander S, Ivanciu C, Papanikolaou A, Van der Stede Y, Blome S, Guberti V, Loi F, More S, Olsevskis E, Thulke HH, Viltrop A. ASF Exit Strategy: Providing cumulative evidence of the absence of African swine fever virus circulation in wild boar populations using standard surveillance measures. EFSA J 2021; 19:e06419. [PMID: 33717352 PMCID: PMC7926520 DOI: 10.2903/j.efsa.2021.6419] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
EFSA assessed the role of seropositive wild boar in African swine fever (ASF) persistence. Surveillance data from Estonia and Latvia investigated with a generalised equation method demonstrated a significantly slower decline in seroprevalence in adult animals compared with subadults. The seroprevalence in adults, taking more than 24 months to approach zero after the last detection of ASFV circulation, would be a poor indicator to demonstrate the absence of virus circulation. A narrative literature review updated the knowledge on the mortality rate, the duration of protective immunity and maternal antibodies and transmission parameters. In addition, parameters potentially leading to prolonged virus circulation (persistence) in wild boar populations were reviewed. A stochastic explicit model was used to evaluate the dynamics of virus prevalence, seroprevalence and the number of carcasses attributed to ASF. Secondly, the impact of four scenarios on the duration of ASF virus (ASFV) persistence was evaluated with the model, namely a: (1) prolonged, lifelong infectious period, (2) reduction in the case-fatality rate and prolonged transient infectiousness; (3) change in duration of protective immunity and (4) change in the duration of protection from maternal antibodies. Only the lifelong infectious period scenario had an important prolonging effect on the persistence of ASF. Finally, the model tested the performance of different proposed surveillance strategies to provide evidence of the absence of virus circulation (Exit Strategy). A two-phase approach (Screening Phase, Confirmation Phase) was suggested for the Exit Strategy. The accuracy of the Exit Strategy increases with increasing numbers of carcasses collected and tested. The inclusion of active surveillance based on hunting has limited impact on the performance of the Exit Strategy compared with lengthening of the monitoring period. This performance improvement should be reasonably balanced against an unnecessary prolonged 'time free' with only a marginal gain in performance. Recommendations are provided for minimum monitoring periods leading to minimal failure rates of the Exit Strategy. The proposed Exit Strategy would fail with the presence of lifelong infectious wild boar. That said, it should be emphasised that the existence of such animals is speculative, based on current knowledge.
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15
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Penrith ML, Bastos A, Chenais E. With or without a Vaccine-A Review of Complementary and Alternative Approaches to Managing African Swine Fever in Resource-Constrained Smallholder Settings. Vaccines (Basel) 2021; 9:vaccines9020116. [PMID: 33540948 PMCID: PMC7913123 DOI: 10.3390/vaccines9020116] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/28/2021] [Accepted: 01/28/2021] [Indexed: 02/07/2023] Open
Abstract
The spectacular recent spread of African swine fever (ASF) in Eastern Europe and Asia has been strongly associated, as it is in the endemic areas in Africa, with free-ranging pig populations and low-biosecurity backyard pig farming. Managing the disease in wild boar populations and in circumstances where the disease in domestic pigs is largely driven by poverty is particularly challenging and may remain so even in the presence of effective vaccines. The only option currently available to prevent ASF is strict biosecurity. Among small-scale pig farmers biosecurity measures are often considered unaffordable or impossible to implement. However, as outbreaks of ASF are also unaffordable, the adoption of basic biosecurity measures is imperative to achieve control and prevent losses. Biosecurity measures can be adapted to fit smallholder contexts, culture and costs. A longer-term approach that could prove valuable particularly for free-ranging pig populations would be exploitation of innate resistance to the virus, which is fully effective in wild African suids and has been observed in some domestic pig populations in areas of prolonged endemicity. We explore available options for preventing ASF in terms of feasibility, practicality and affordability among domestic pig populations that are at greatest risk of exposure to ASF.
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Affiliation(s)
- Mary-Louise Penrith
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa
- Correspondence: ; Tel.: +27-12-342-1514
| | - Armanda Bastos
- Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria 0028, South Africa;
| | - Erika Chenais
- Department of Disease Control and Epidemiology, National Veterinary Institute, S-751 89 Uppsala, Sweden;
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16
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Forth JH, Forth LF, Lycett S, Bell-Sakyi L, Keil GM, Blome S, Calvignac-Spencer S, Wissgott A, Krause J, Höper D, Kampen H, Beer M. Identification of African swine fever virus-like elements in the soft tick genome provides insights into the virus' evolution. BMC Biol 2020; 18:136. [PMID: 33032594 PMCID: PMC7542975 DOI: 10.1186/s12915-020-00865-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 09/04/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND African swine fever virus (ASFV) is a most devastating pathogen affecting swine. In 2007, ASFV was introduced into Eastern Europe where it continuously circulates and recently reached Western Europe and Asia, leading to a socio-economic crisis of global proportion. In Africa, where ASFV was first described in 1921, it is transmitted between warthogs and soft ticks of the genus Ornithodoros in a so-called sylvatic cycle. However, analyses into this virus' evolution are aggravated by the absence of any closely related viruses. Even ancient endogenous viral elements, viral sequences integrated into a host's genome many thousand years ago that have proven extremely valuable to analyse virus evolution, remain to be identified. Therefore, the evolution of ASFV, the only known DNA virus transmitted by arthropods, remains a mystery. RESULTS For the identification of ASFV-like sequences, we sequenced DNA from different recent Ornithodoros tick species, e.g. O. moubata and O. porcinus, O. moubata tick cells and also 100-year-old O. moubata and O. porcinus ticks using high-throughput sequencing. We used BLAST analyses for the identification of ASFV-like sequences and further analysed the data through phylogenetic reconstruction and molecular clock analyses. In addition, we performed tick infection experiments as well as additional small RNA sequencing of O. moubata and O. porcinus soft ticks. CONCLUSION Here, we show that soft ticks of the Ornithodoros moubata group, the natural arthropod vector of ASFV, harbour African swine fever virus-like integrated (ASFLI) elements corresponding to up to 10% (over 20 kb) of the ASFV genome. Through orthologous dating and molecular clock analyses, we provide data suggesting that integration could have occurred over 1.47 million years ago. Furthermore, we provide data showing ASFLI-element specific siRNA and piRNA in ticks and tick cells allowing for speculations on a possible role of ASFLI-elements in RNA interference-based protection against ASFV in ticks. We suggest that these elements, shaped through many years of co-evolution, could be part of an evolutionary virus-vector 'arms race', a finding that has not only high impact on our understanding of the co-evolution of viruses with their hosts but also provides a glimpse into the evolution of ASFV.
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Affiliation(s)
- Jan H Forth
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Leonie F Forth
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Samantha Lycett
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, Scotland, UK
| | - Lesley Bell-Sakyi
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, 146 Brownlow Hill, Liverpool, L3 5RF, UK
| | - Günther M Keil
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Sandra Blome
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | | | - Antje Wissgott
- Max Planck Institute for the Science of Human History, Kahlaische Str. 10, 07745, Jena, Germany
| | - Johannes Krause
- Max Planck Institute for the Science of Human History, Kahlaische Str. 10, 07745, Jena, Germany
| | - Dirk Höper
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Helge Kampen
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Martin Beer
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany.
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17
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Boklund A, Dhollander S, Chesnoiu Vasile T, Abrahantes JC, Bøtner A, Gogin A, Gonzalez Villeta LC, Gortázar C, More SJ, Papanikolaou A, Roberts H, Stegeman A, Ståhl K, Thulke HH, Viltrop A, Van der Stede Y, Mortensen S. Risk factors for African swine fever incursion in Romanian domestic farms during 2019. Sci Rep 2020; 10:10215. [PMID: 32576841 PMCID: PMC7311386 DOI: 10.1038/s41598-020-66381-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 05/18/2020] [Indexed: 01/06/2023] Open
Abstract
African swine fever (ASF) entered Georgia in 2007 and the EU in 2014. In the EU, the virus primarily spread in wild boar (Sus scrofa) in the period from 2014-2018. However, from the summer 2018, numerous domestic pig farms in Romania were affected by ASF. In contrast to the existing knowledge on ASF transmission routes, the understanding of risk factors and the importance of different transmission routes is still limited. In the period from May to September 2019, 655 Romanian pig farms were included in a matched case-control study investigating possible risk factors for ASF incursion in commercial and backyard pig farms. The results showed that close proximity to outbreaks in domestic farms was a risk factor in commercial as well as backyard farms. Furthermore, in backyard farms, herd size, wild boar abundance around the farm, number of domestic outbreaks within 2 km around farms, short distance to wild boar cases and visits of professionals working on farms were statistically significant risk factors. Additionally, growing crops around the farm, which could potentially attract wild boar, and feeding forage from ASF affected areas to the pigs were risk factors for ASF incursion in backyard farms.
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Affiliation(s)
- A Boklund
- University of Copenhagen, Faculty of Health and Medical Sciences, Section for Animal Welfare and Disease Control, Grønnegårdsvej 8, 1870, Frederiksberg C, Denmark.
| | - S Dhollander
- European Food Safety Authority, Via Carlo Magno 1A, 43126, Parma, Italy
| | - T Chesnoiu Vasile
- The National Sanitary Veterinary and Food Safety Authority, Bucharest, Piata Free Press no. 1 Body D1, District 1, Post Code 013 701, Bucharest, Romania
| | - J C Abrahantes
- European Food Safety Authority, Via Carlo Magno 1A, 43126, Parma, Italy
| | - A Bøtner
- University of Copenhagen, Faculty of Health and Medical Sciences, Section for Veterinary Clinical Microbiology, Stigbøjlen 4, 1870, Frederiksberg C, Denmark
- Statens Serum Institut, Department of Virus and Microbiological Special Diagnostics, Artillerivej 5, 2300, Copenhagen S, Denmark
| | - A Gogin
- Federal Research Center for Virology and Microbiology, 601125, Volginsky, Russia
| | | | - C Gortázar
- SaBio research group at IREC (Universidad de Castilla-La Mancha & CSIC), Ronda de Toledo 12, 13003, Ciudad Real, Spain
| | - S J More
- Centre for Veterinary Epidemiology and Risk Analysis, UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin, D04 W6F6, Ireland
| | - A Papanikolaou
- European Food Safety Authority, Via Carlo Magno 1A, 43126, Parma, Italy
| | - H Roberts
- Department for Environment Food and Rural Affairs (DEFRA), Exotic Disease Control team, Area 2D, Nobel House, 17 Smith Square, London, SW1P 3JR, England
| | - A Stegeman
- Utrecht University, Faculty of Veterinary Medicine, Yalelaan 7, Utrecht, The Netherlands
| | - K Ståhl
- National Veterinary Institute, 751 89, Uppsala, Sweden
| | - H H Thulke
- Helmholtz Centre for Environmental Research GmbH - UFZ, Department of Ecological Modelling, PG EcoEpi, Permoserstr. 15, Leipzig, Germany
| | - A Viltrop
- Estonian University of Life Sciences, Institute of Veterinary Medicine and Animal Sciences, Kreutzwaldi 62, Tartu, 51006, Estonia
| | - Y Van der Stede
- European Food Safety Authority, Via Carlo Magno 1A, 43126, Parma, Italy
| | - S Mortensen
- Danish Veterinary and Food Administration, Stationsparken 31-33, 2600, Glostrup, Denmark
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18
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Olesen AS, Belsham GJ, Bruun Rasmussen T, Lohse L, Bødker R, Halasa T, Boklund A, Bøtner A. Potential routes for indirect transmission of African swine fever virus into domestic pig herds. Transbound Emerg Dis 2020; 67:1472-1484. [PMID: 32150785 DOI: 10.1111/tbed.13538] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/18/2020] [Accepted: 03/05/2020] [Indexed: 12/16/2022]
Abstract
Following its introduction into Georgia in 2007, African swine fever virus (ASFV) has become widespread on the European continent and in Asia. In many cases, the exact route of introduction into domestic pig herds cannot be determined, but most introductions are attributed to indirect virus transmission. In this review, we describe knowledge gained about different matrices that may allow introduction of the virus into pig herds. These matrices include uncooked pig meat, processed pig-derived products, feed, matrices contaminated with the virus and blood-feeding invertebrates. Knowledge gaps still exist, and both field studies and laboratory research are needed to enhance understanding of the risks for ASFV introductions, especially via virus-contaminated materials, including bedding and feed, and via blood-feeding, flying insects. Knowledge obtained from such studies can be applied to epidemiological risk assessments for the different transmission routes. Such assessments can be utilized to help predict the most effective biosecurity and control strategies.
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Affiliation(s)
- Ann Sofie Olesen
- Section of Veterinary Clinical Microbiology, Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Graham J Belsham
- Section of Veterinary Clinical Microbiology, Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Thomas Bruun Rasmussen
- Department of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Copenhagen, Denmark
| | - Louise Lohse
- Department of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Copenhagen, Denmark
| | - René Bødker
- Section of Animal Welfare and Disease Control, Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tariq Halasa
- Section of Animal Welfare and Disease Control, Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anette Boklund
- Section of Animal Welfare and Disease Control, Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anette Bøtner
- Section of Veterinary Clinical Microbiology, Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C, Denmark.,Department of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Copenhagen, Denmark
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19
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Pereira de Oliveira R, Hutet E, Paboeuf F, Duhayon M, Boinas F, Perez de Leon A, Filatov S, Vial L, Le Potier MF. Comparative vector competence of the Afrotropical soft tick Ornithodoros moubata and Palearctic species, O. erraticus and O. verrucosus, for African swine fever virus strains circulating in Eurasia. PLoS One 2019; 14:e0225657. [PMID: 31774871 PMCID: PMC6881060 DOI: 10.1371/journal.pone.0225657] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 11/08/2019] [Indexed: 11/26/2022] Open
Abstract
African swine fever (ASF) is a lethal hemorrhagic disease in domestic pigs and wild suids caused by African swine fever virus (ASFV), which threatens the swine industry globally. In its native African enzootic foci, ASFV is naturally circulating between soft ticks of the genus Ornithodoros, especially in the O. moubata group, and wild reservoir suids, such as warthogs (Phacochoerus spp.) that are bitten by infected soft ticks inhabiting their burrows. While the ability of some Afrotropical soft ticks to transmit and maintain ASFV is well established, the vector status of Palearctic soft tick species for ASFV strains currently circulating in Eurasia remains largely unknown. For example, the Iberian soft tick O. erraticus is a known vector and reservoir of ASFV, but its ability to transmit different ASFV strains has not been assessed since ASF re-emerged in Europe in 2007. Little is known about vector competence for ASFV in other species, such as O. verrucosus, which occurs in southern parts of Eastern Europe, including Ukraine and parts of Russia, and in the Caucasus. Therefore, we conducted transmission trials with two Palearctic soft tick species, O. erraticus and O. verrucosus, and the Afrotropical species O. moubata. We tested the ability of ticks to transmit virulent ASFV strains, including one of direct African origin (Liv13/33), and three from Eurasia that had been involved in previous (OurT88/1), and the current epizooties (Georgia2007/1 and Ukr12/Zapo). Our experimental results showed that O. moubata was able to transmit the African and Eurasian ASFV strains, whereas O. erraticus and O. verrucosus failed to transmit the Eurasian ASFV strains. However, naïve pigs showed clinical signs of ASF when inoculated with homogenates of crushed O. erraticus and O. verrucosus ticks that fed on viraemic pigs, which proved the infectiousness of ASFV contained in the ticks. These results documented that O. erraticus and O. verrucosus are unlikely to be capable vectors of ASFV strains currently circulating in Eurasia. Additionally, the persistence of infection in soft ticks for several months reaffirms that the infectious status of a given tick species is only part of the data required to assess its vector competence for ASFV.
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Affiliation(s)
- Rémi Pereira de Oliveira
- Swine Virology and Immunology Unit, Laboratoire de Ploufragan-Plouzané-Niort, Agence Nationale de Sécurité Sanitaire (ANSES), Ploufragan, France
- UMR ASTRE Animal Santé, Territoires, Risques et Ecosystèmes, Centre de coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Montpellier, France
- University of Montpellier, Montpellier, France
| | - Evelyne Hutet
- Swine Virology and Immunology Unit, Laboratoire de Ploufragan-Plouzané-Niort, Agence Nationale de Sécurité Sanitaire (ANSES), Ploufragan, France
| | - Frédéric Paboeuf
- Swine Virology and Immunology Unit, Laboratoire de Ploufragan-Plouzané-Niort, Agence Nationale de Sécurité Sanitaire (ANSES), Ploufragan, France
| | - Maxime Duhayon
- UMR ASTRE Animal Santé, Territoires, Risques et Ecosystèmes, Centre de coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Montpellier, France
| | - Fernando Boinas
- CIISA—Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Lisboa, Portugal
| | - Adalberto Perez de Leon
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, USDA-ARS, Kerrville, Texas, United States of America
| | - Serhii Filatov
- National Scientific Center Institute of Experimental and Clinical Veterinary Medicine, NSC IECVM), Kharkiv, Ukraine
| | - Laurence Vial
- UMR ASTRE Animal Santé, Territoires, Risques et Ecosystèmes, Centre de coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Montpellier, France
- University of Montpellier, Montpellier, France
| | - Marie-Frédérique Le Potier
- Swine Virology and Immunology Unit, Laboratoire de Ploufragan-Plouzané-Niort, Agence Nationale de Sécurité Sanitaire (ANSES), Ploufragan, France
- * E-mail:
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20
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Herm R, Tummeleht L, Jürison M, Vilem A, Viltrop A. Trace amounts of African swine fever virus DNA detected in insects collected from an infected pig farm in Estonia. Vet Med Sci 2019; 6:100-104. [PMID: 31560174 PMCID: PMC7036316 DOI: 10.1002/vms3.200] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Background African swine fever (ASF), a severe multi‐systemic disease in pigs, was introduced into Estonia in 2014. The majority of outbreaks have occurred during the summer months. Given that ASFV is transmitted in a sylvatic cycle that includes the transmission by African soft ticks and that mechanical transmission by flying insects was shown, transmission by other arthropod vectors need to be considered. Objectives Here, we report the results of a pilot study on flying insects caught on an outbreak farm during epidemiological investigations. Methods In brief, 15 different insect species (flies and mosquitoes) were collected by random catch using an aerial net. Nucleic acids derived from these samples or their pools were tested for African swine fever virus (ASFV) DNA by real‐time PCR. Results and Conclusions Viral DNA was detected in small quantities in two samples from flies and mosquitoes. Given the slow spread of virus within the farm, the impact of these findings seems rather low, but a role in local transmission cannot be ruled out. However, given the very low number of insects sampled, and taken into the account that viral isolation was not performed and insects outside the farm were not investigated, future investigations are needed to assess the true impact of insects as mechanical vectors.
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Affiliation(s)
- Reet Herm
- Equine Clinic, Chair of Clinical Veterinary Medicine, Estonian University of Life Sciences, Tartu, Estonia
| | - Lea Tummeleht
- Chair of Veterinary Bio- and Population Medicine, Estonian University of Life Sciences, Tartu, Estonia
| | - Margret Jürison
- Chair of Plant Health, Estonian University of Life Sciences, Tartu, Estonia
| | - Annika Vilem
- Department of Molecular Analysis, Veterinary and Food Laboratory, Tartu, Estonia
| | - Arvo Viltrop
- Chair of Veterinary Bio- and Population Medicine, Estonian University of Life Sciences, Tartu, Estonia
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21
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Mazur-Panasiuk N, Żmudzki J, Woźniakowski G. African Swine Fever Virus - Persistence in Different Environmental Conditions and the Possibility of its Indirect Transmission. J Vet Res 2019; 63:303-310. [PMID: 31572808 PMCID: PMC6749736 DOI: 10.2478/jvetres-2019-0058] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 08/12/2019] [Indexed: 11/25/2022] Open
Abstract
Since 2007, African swine fever (ASF) has posed a serious threat to the European swine industry. In Poland, the numbers of reported outbreaks in pigs and affected areas grow every year. In 2018, the disease was noted in Western Europe, in Belgium specifically, where several hundred infected wild boars have been detected so far. In 2018, the virus unexpectedly emerged in pig holdings in eastern China, northern Mongolia, Vietnam, and Cambodia, causing worldwide concern about its further spread. Since there is still no vaccine available, the only approach to control the disease is biosecurity. Identification of potential sources of the virus is extremely important in light of its phenomenal survivability. The review summarises the current knowledge about ASFV survivability and resistance to environmental conditions, and discusses the role of indirect contact in spreading the disease.
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Affiliation(s)
- Natalia Mazur-Panasiuk
- Department of Swine Diseases, National Veterinary Research Institute, 24-100Puławy, Poland
| | - Jacek Żmudzki
- Department of Swine Diseases, National Veterinary Research Institute, 24-100Puławy, Poland
| | - Grzegorz Woźniakowski
- Department of Swine Diseases, National Veterinary Research Institute, 24-100Puławy, Poland
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22
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Golnar AJ, Martin E, Wormington JD, Kading RC, Teel PD, Hamer SA, Hamer GL. Reviewing the Potential Vectors and Hosts of African Swine Fever Virus Transmission in the United States. Vector Borne Zoonotic Dis 2019; 19:512-524. [PMID: 30785371 PMCID: PMC6602103 DOI: 10.1089/vbz.2018.2387] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
African swine fever virus (ASFV) continues to threaten global animal health and agricultural biosecurity. Mitigating the establishment of ASFV in the United States (U.S.) is contingent on (1) the identification of arthropod vectors and vertebrate hosts that are capable of viral maintenance and transmission in the U.S. and (2) knowledge of vector-host associations that may permit transmission. We aggregated data on vector competence, host competence and tick–host associations by systematic review of published articles and collection records to identify species that may support the invasion of ASFV in the U.S. Three species of competent soft ticks occur in the U.S., Ornithodoros coriaceus, Ornithodoros turicata, and Ornithodoros puertoricensis, however, vector competence for the majority of soft ticks in the U.S. remains unknown. Three species of competent vertebrate hosts currently occur in the U.S.: domestic pigs (Sus scrofa domesticus), feral hogs (Sus scrofa), and common warthogs (Phacochoerus africanus). Hierarchical hazard categories based on vector competence, tick–host contact rates, and vector abundance were used to semiquantitatively rank U.S. soft tick species by their relative risk for contributing to ASFV transmission to identify which soft tick species are a priority for future studies. High-risk vector and host species identified in this study can be used to focus ASFV risk assessments in the U.S., guide targeted surveillance and control strategies, and proactively prepare for an ASFV incursion event. Results indicate O. coriaceus, O. turicata, and O. puertoricensis demonstrate the highest relative risk for contributing to ASFV transmission in the U.S., however, many gaps in knowledge exist preventing the full evaluation of at least 30 soft tick species in the U.S. Further study is required to identify soft tick vectors that interact with feral swine populations, elucidate vector competence, and further understand the biology of soft tick species.
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Affiliation(s)
- Andrew J Golnar
- 1 Texas A&M AgriLife Research, Department of Entomology, Texas A&M University, College Station, Texas
| | - Estelle Martin
- 1 Texas A&M AgriLife Research, Department of Entomology, Texas A&M University, College Station, Texas
| | - Jillian D Wormington
- 2 Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas
| | - Rebekah C Kading
- 3 Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, Colorado
| | - Pete D Teel
- 1 Texas A&M AgriLife Research, Department of Entomology, Texas A&M University, College Station, Texas
| | - Sarah A Hamer
- 2 Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas
| | - Gabriel L Hamer
- 1 Texas A&M AgriLife Research, Department of Entomology, Texas A&M University, College Station, Texas
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23
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Talactac MR, Hernandez EP, Fujisaki K, Tanaka T. A Continuing Exploration of Tick-Virus Interactions Using Various Experimental Viral Infections of Hard Ticks. Front Physiol 2018; 9:1728. [PMID: 30564140 PMCID: PMC6288443 DOI: 10.3389/fphys.2018.01728] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/16/2018] [Indexed: 01/07/2023] Open
Abstract
To fully unravel the ixodid ticks’ role as vectors of viral pathogens, their susceptibility to new control measures, and their ability to develop acaricide resistance, acclimatization of ticks under laboratory conditions is greatly needed. However, the unique and complicated feeding behavior of these ticks compared to that of other hematophagous arthropods requires efficient and effective techniques to infect them with tick-borne viruses (TBVs). In addition, relatively expensive maintenance of animals for blood feeding and associated concerns about animal welfare critically limit our understanding of TBVs. This mini review aims to summarize the current knowledge about the artificial infection of hard ticks with viral pathogens, which is currently used to elucidate virus transmission and vector competence and to discover immune modulators related to tick–virus interactions. This review will also present the advantages and limitations of the current techniques for tick infection. Fortunately, new artificial techniques arise, and the limitations of current protocols are greatly reduced as researchers continuously improve, streamline, and standardize the laboratory procedures to lower cost and produce better adoptability. In summary, convenient and low-cost techniques to study the interactions between ticks and TBVs provide a great opportunity to identify new targets for the future control of TBVs.
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Affiliation(s)
- Melbourne Rio Talactac
- Department of Clinical and Population Health, College of Veterinary Medicine and Biomedical Sciences, Cavite State University, Cavite, Philippines.,Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima, Japan
| | - Emmanuel P Hernandez
- Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima, Japan
| | - Kozo Fujisaki
- National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Tetsuya Tanaka
- Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima, Japan
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24
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Frant M, Woźniakowski G, Pejsak Z. African Swine Fever (ASF) and Ticks. No Risk of Tick-mediated ASF Spread in Poland and Baltic States. J Vet Res 2017; 61:375-380. [PMID: 29978098 PMCID: PMC5937333 DOI: 10.1515/jvetres-2017-0055] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 11/07/2017] [Indexed: 11/15/2022] Open
Abstract
Infectious diseases of swine, particularly zoonoses, have had a significant influence on nutritional safety and availability of pig meat as high-energy protein product since the time that pigs were domesticated back in the 7th century BC. The main sources of swine infectious diseases include the so-called primary sources (direct infection, i.e. through contact with infected and sick animals) and secondary sources (contaminated meat products, slaughter products, and vectors, including ticks). At present, the most serious epidemiological and economic threat to swine breeding in Europe is African swine fever (ASF). This disease, originally coming from Africa, is incurable and causes death of infected pigs and wild boars during 7−10 days after infection. Among the various factors that influence the spread of ASF, important role is played by ticks from the genus Ornithodoros, mainly from the species Ornithodoros moubata. Research on the ASF indicates that other species of ticks can also transmit the virus to healthy pigs in laboratory conditions. Sylvatic and domestic cycles of ASF virus transmission, which have been described so far, require further studies and updating in order to point the potential new vectors in the Caucasus and Eastern Europe affected by the ASF. Effective methods of control and biosecurity may significantly slow down the spread of ASF, which undoubtedly is a major threat to world pig production and international swine trade.
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Affiliation(s)
- Maciej Frant
- Department of Swine Diseases, National Veterinary Research Institute, 24-100 Puławy, Poland
| | - Grzegorz Woźniakowski
- Department of Swine Diseases, National Veterinary Research Institute, 24-100 Puławy, Poland
| | - Zygmunt Pejsak
- Department of Swine Diseases, National Veterinary Research Institute, 24-100 Puławy, Poland
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25
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Schulz K, Staubach C, Blome S. African and classical swine fever: similarities, differences and epidemiological consequences. Vet Res 2017; 48:84. [PMID: 29183365 PMCID: PMC5706370 DOI: 10.1186/s13567-017-0490-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 11/08/2017] [Indexed: 11/19/2022] Open
Abstract
For the global pig industry, classical (CSF) and African swine fever (ASF) outbreaks are a constantly feared threat. Except for Sardinia, ASF was eradicated in Europe in the late 1990s, which led to a research focus on CSF because this disease continued to be present. However, ASF remerged in eastern Europe in 2007 and the interest in the disease, its control and epidemiology increased tremendously. The similar names and the same susceptible species suggest a similarity of the two viral diseases, a related biological behaviour and, correspondingly, similar epidemiological features. However, there are several essential differences between both diseases, which need to be considered for the design of control or preventive measures. In the present review, we aimed to collate differences and similarities of the two diseases that impact epidemiology and thus the necessary control actions. Our objective was to discuss critically, if and to which extent the current knowledge can be transferred from one disease to the other and where new findings should lead to a critical review of measures relating to the prevention, control and surveillance of ASF and CSF. Another intention was to identify research gaps, which need to be closed to increase the chances of a successful eradication of ASF and therefore for a decrease of the economic threat for pig holdings and the international trade.
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Affiliation(s)
- Katja Schulz
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald, Insel Riems Germany
| | - Christoph Staubach
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald, Insel Riems Germany
| | - Sandra Blome
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Diagnostic Virology, Südufer 10, 17493 Greifswald, Insel Riems Germany
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26
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Forth JH, Amendt J, Blome S, Depner K, Kampen H. Evaluation of blowfly larvae (Diptera: Calliphoridae) as possible reservoirs and mechanical vectors of African swine fever virus. Transbound Emerg Dis 2017; 65:e210-e213. [PMID: 28762629 DOI: 10.1111/tbed.12688] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Indexed: 11/28/2022]
Abstract
In 2014, highly virulent African swine fever virus (ASFV) was introduced into the Baltic States and Poland, with new cases being reported almost every week from wild boar and also from domestic pigs. Contrary to initial predictions that the disease would either die out due to the high virulence of the virus strain or spread rapidly in westerly direction, the infection became endemic and spread slowly. The unexpected disease epidemiology led to the hypothesis that hitherto unconsidered factors might contribute to virus persistence and dispersal. To check whether arthropod species feeding and developing on infected carcasses might be involved, larvae of two commonly found blowfly species, Lucilia sericata and Calliphora vicina, were experimentally bred on ASFV-infected spleen tissue. After different time intervals, developing larvae and pupae were tested for infectious virus and viral DNA. By qPCR, contamination of the blowfly larvae and pupae with ASFV-DNA could be demonstrated even after several washing steps, proving the uptake of virus during feeding in the larval stage. However, infectious virus could never be isolated. By contrast, the larvae appeared to have inactivated ASFV in the offered tissue, which might be explained by the known anti-biotic effect of salivary secretions. It is concluded that immature blowfly stages do not play a relevant role as reservoirs or mechanical vectors of ASFV.
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Affiliation(s)
- J H Forth
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - J Amendt
- Institute of Forensic Medicine, Goethe University, Frankfurt, Germany
| | - S Blome
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - K Depner
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - H Kampen
- Federal Research Institute for Animal Health, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
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27
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Mansfield KL, Jizhou L, Phipps LP, Johnson N. Emerging Tick-Borne Viruses in the Twenty-First Century. Front Cell Infect Microbiol 2017; 7:298. [PMID: 28744449 PMCID: PMC5504652 DOI: 10.3389/fcimb.2017.00298] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 06/19/2017] [Indexed: 12/18/2022] Open
Abstract
Ticks, as a group, are second only to mosquitoes as vectors of pathogens to humans and are the primary vector for pathogens of livestock, companion animals, and wildlife. The role of ticks in the transmission of viruses has been known for over 100 years and yet new pathogenic viruses are still being detected and known viruses are continually spreading to new geographic locations. Partly as a result of their novelty, tick-virus interactions are at an early stage in understanding. For some viruses, even the principal tick-vector is not known. It is likely that tick-borne viruses will continue to emerge and challenge public and veterinary health long into the twenty-first century. However, studies focusing on tick saliva, a critical component of tick feeding, virus transmission, and a target for control of ticks and tick-borne diseases, point toward solutions to emerging viruses. The aim of this review is to describe some currently emerging tick-borne diseases, their causative viruses, and to discuss research on virus-tick interactions. Through focus on this area, future protein targets for intervention and vaccine development may be identified.
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Affiliation(s)
- Karen L Mansfield
- Animal and Plant Health AgencyAddlestone, United Kingdom.,Institute of Infection and Global Health, University of LiverpoolLiverpool, United Kingdom
| | - Lv Jizhou
- Animal and Plant Health AgencyAddlestone, United Kingdom.,Chinese Academy of Inspection and QuarantineBeijing, China
| | - L Paul Phipps
- Animal and Plant Health AgencyAddlestone, United Kingdom
| | - Nicholas Johnson
- Animal and Plant Health AgencyAddlestone, United Kingdom.,Faculty of Health and Medicine, University of SurreyGuildford, United Kingdom
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28
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More S, Bicout D, Bøtner A, Butterworth A, Calistri P, De Koeijer A, Depner K, Edwards S, Garin-Bastuji B, Good M, Gortazar Schmidt C, Michel V, Miranda MA, Nielsen SS, Raj M, Sihvonen L, Spoolder H, Thulke HH, Velarde A, Willeberg P, Winckler C, Bau A, Beltran-Beck B, Carnesecchi E, Casier P, Czwienczek E, Dhollander S, Georgiadis M, Gogin A, Pasinato L, Richardson J, Riolo F, Rossi G, Watts M, Lima E, Stegeman JA. Vector-borne diseases. EFSA J 2017; 15:e04793. [PMID: 32625493 PMCID: PMC7009857 DOI: 10.2903/j.efsa.2017.4793] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
After a request from the European Commission, EFSA's Panel on Animal Health and Welfare summarised the main characteristics of 36 vector-borne diseases (VBDs) in https://efsa.maps.arcgis.com/apps/PublicGallery/index.html?appid=dfbeac92aea944599ed1eb754aa5e6d1. The risk of introduction in the EU through movement of livestock or pets was assessed for each of the 36 VBDs individually, using a semiquantitative Method to INTegrate all relevant RISK aspects (MINTRISK model), which was further modified to a European scale into the http://www3.lei.wur.nl/mintrisk/ModelMgt.aspx. Only eight of the 36 VBD-agents had an overall rate of introduction in the EU (being the combination of the rate of entry, vector transmission and establishment) which was estimated to be above 0.001 introductions per year. These were Crimean-Congo haemorrhagic fever virus, bluetongue virus, West Nile virus, Schmallenberg virus, Hepatozoon canis, Leishmania infantum, Bunyamwera virus and Highlands J. virus. For these eight diseases, the annual extent of spread was assessed, assuming the implementation of available, authorised prevention and control measures in the EU. Further, the probability of overwintering was assessed, as well as the possible impact of the VBDs on public health, animal health and farm production. For the other 28 VBD-agents for which the rate of introduction was estimated to be very low, no further assessments were made. Due to the uncertainty related to some parameters used for the risk assessment or the instable or unpredictability disease situation in some of the source regions, it is recommended to update the assessment when new information becomes available. Since this risk assessment was carried out for large regions in the EU for many VBD-agents, it should be considered as a first screening. If a more detailed risk assessment for a specific VBD is wished for on a national or subnational level, the EFSA-VBD-RISK-model is freely available for this purpose.
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29
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Sanna G, Dei Giudici S, Bacciu D, Angioi PP, Giammarioli M, De Mia GM, Oggiano A. Improved Strategy for Molecular Characterization of African Swine Fever Viruses from Sardinia, Based on Analysis of p30, CD2V and I73R
/I329L
Variable Regions. Transbound Emerg Dis 2016; 64:1280-1286. [DOI: 10.1111/tbed.12504] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Indexed: 11/29/2022]
Affiliation(s)
- G. Sanna
- Istituto Zooprofilattico Sperimentale della Sardegna; Sassari Italy
| | - S. Dei Giudici
- Istituto Zooprofilattico Sperimentale della Sardegna; Sassari Italy
| | - D. Bacciu
- Istituto Zooprofilattico Sperimentale della Sardegna; Sassari Italy
| | - P. P. Angioi
- Istituto Zooprofilattico Sperimentale della Sardegna; Sassari Italy
| | - M. Giammarioli
- Istituto Zooprofilattico Sperimentale dell'Umbria e Marche; Perugia Italy
| | - G. M. De Mia
- Istituto Zooprofilattico Sperimentale dell'Umbria e Marche; Perugia Italy
| | - A. Oggiano
- Istituto Zooprofilattico Sperimentale della Sardegna; Sassari Italy
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30
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Guinat C, Gogin A, Blome S, Keil G, Pollin R, Pfeiffer DU, Dixon L. Transmission routes of African swine fever virus to domestic pigs: current knowledge and future research directions. Vet Rec 2016; 178:262-7. [PMID: 26966305 PMCID: PMC4819659 DOI: 10.1136/vr.103593] [Citation(s) in RCA: 191] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
African swine fever (ASF) is a major threat to the pig industry in Europe. Since 2007, ASF outbreaks have been ongoing in the Caucasus, Eastern Europe and the Baltic countries, causing severe economic losses for many pig farmers and pork producers. In addition, the number of ASF cases in wild boar populations has dramatically increased over the past few years. Evidence supports direct contact with infectious domestic pigs and wild boars, and consumption of contaminated feed, as the main transmission routes of ASF virus (ASFV) to domestic pigs. However, significant knowledge gaps highlight the urgent need for research to investigate the dynamics of indirect transmission via the environment, the minimal infective doses for contaminated feed ingestion, the probability of effective contacts between infectious wild boars and domestic pigs, the potential for recovered animals to become carriers and a reservoir for transmission, the potential virus persistence within wild boar populations and the influence of human behaviour for the spread of ASFV. This will provide an improved scientific basis to optimise current interventions and develop new tools and strategies to reduce the risk of ASFV transmission to domestic pigs.
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Affiliation(s)
- Claire Guinat
- Royal Veterinary College, Veterinary Epidemiology, Economics and Public Health Group, Hawkshead Lane, Hatfield, Hertfordshire AL9 7TA, UK
| | - Andrey Gogin
- European Food Safety Authority, Via Carlo Magno 1A, 43126 Parma, Italy
| | - Sandra Blome
- Friedrich-Loeffler Institut, Sudufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Guenther Keil
- Friedrich-Loeffler Institut, Sudufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Reiko Pollin
- Friedrich-Loeffler Institut, Sudufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Dirk U Pfeiffer
- Royal Veterinary College, Veterinary Epidemiology, Economics and Public Health Group, Hawkshead Lane, Hatfield, Hertfordshire AL9 7TA, UK
| | - Linda Dixon
- The Pirbright Institute, Ash Road, Pirbright, Surrey GU24 0NF, UK
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31
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Temmam S, Monteil-Bouchard S, Sambou M, Aubadie-Ladrix M, Azza S, Decloquement P, Khalil JYB, Baudoin JP, Jardot P, Robert C, La Scola B, Mediannikov OY, Raoult D, Desnues C. Faustovirus-Like Asfarvirus in Hematophagous Biting Midges and Their Vertebrate Hosts. Front Microbiol 2015; 6:1406. [PMID: 26733117 PMCID: PMC4679923 DOI: 10.3389/fmicb.2015.01406] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 11/25/2015] [Indexed: 11/29/2022] Open
Abstract
Faustovirus, a new Asfarviridae-related giant virus, was recently isolated in Vermamoeba vermiformis, a protist found in sewage water in various geographical locations and occasionally reported in human eye infection cases. As part of a global metagenomic analysis of viral communities existing in biting midges, we report here for the first time the identification and isolation of a Faustovirus-like virus in hematophagous arthropods and its detection in their animal hosts. The DNA virome analysis of three pools of Culicoides sp., engorged female Culicoides imicola and non-engorged male/female C. imicola biting midges collected in Senegal, revealed the presence of amoeba-infecting giant viruses and, among them, a majority of sequences related to Faustovirus. Phylogenetic analyses conducted on several structural genes of Faustovirus confirmed the clustering of the arthropod-borne Faustovirus with sewage-borne Faustoviruses, with a distinct geographical clustering of Senegalese Faustovirus strains. Transmission electron microscopy identified viral particles with morphologies and diameters which were compatible with Faustovirus. The presence of infectious arthropod-borne Faustovirus was finally confirmed by successful isolation on V. vermiformis amoeba. Global proteomic analysis of biting midges identified that arthropods' blood meal originating from cattle, rodents and humans. Further screening of cattle sera and rodent tissue resulted in prevalence of Faustovirus being estimated at 38% in rodents and 14% in cattle, suggesting a possible origin of Faustovirus presence in arthropods via the ingestion of contaminated blood meal. Viral loads were the highest in rodents' urine and kidney samples, suggesting a possible excretion of viral particles into the environment. Faustovirus DNA polymerase-related sequences were also detected in more than 9 and 11% of febrile patients and healthy Senegalese human sera, respectively. Our study thus, highlights the need to investigate the role of arthropods, wildlife, and domestic animals in the lifecycle of amoeba-infecting giant viruses and, in particular, the environmental cycle of Faustovirus.
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Affiliation(s)
- Sarah Temmam
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Sonia Monteil-Bouchard
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Masse Sambou
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Dakar, Senegal
| | - Maxence Aubadie-Ladrix
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Dakar, Senegal
| | - Saïd Azza
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Philippe Decloquement
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Jacques Y Bou Khalil
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Jean-Pierre Baudoin
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Priscilla Jardot
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Catherine Robert
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Bernard La Scola
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille UniversitéMarseille, France; Fondation IHU Méditerranée Infection, Pôle des Maladies Infectieuses et Tropicales Clinique et Biologique, Fédération de Bactériologie-Hygiène-Virologie, Centre Hospitalo-Universitaire Timone, Méditerranée Infection, Assistance Publique - Hôpitaux de MarseilleMarseille, France
| | - Oleg Y Mediannikov
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
| | - Didier Raoult
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille UniversitéMarseille, France; Fondation IHU Méditerranée Infection, Pôle des Maladies Infectieuses et Tropicales Clinique et Biologique, Fédération de Bactériologie-Hygiène-Virologie, Centre Hospitalo-Universitaire Timone, Méditerranée Infection, Assistance Publique - Hôpitaux de MarseilleMarseille, France
| | - Christelle Desnues
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, UM63 Centre National de la Recherche Scientifique 7278 IRD 198 Institut National de la Santé et de la Recherche Médicale U1095, Aix-Marseille Université Marseille, France
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Zheng H, Li AY, Teel PD, Pérez de León AA, Seshu J, Liu J. Biological and physiological characterization of in vitro blood feeding in nymph and adult stages of Ornithodoros turicata (Acari: Argasidae). JOURNAL OF INSECT PHYSIOLOGY 2015; 75:73-79. [PMID: 25783956 DOI: 10.1016/j.jinsphys.2015.03.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 02/27/2015] [Accepted: 03/04/2015] [Indexed: 06/04/2023]
Abstract
Biological and physiological aspects of blood feeding in nymph and adult Ornithodoros turicata were investigated using an in vitro technique combined with electrophysiological recordings and respirometry. The duration of blood feeding through a Parafilm® membrane was similar (19.2-22.6 min) in both developmental stages. The mean (±SD) size of blood meal ingested by nymphs, females, and males was 44.2±17.9, 150.6±48.7, and 74.2±36.9 mg, respectively, representing a 2.5-, 2.8- and 3.0-fold increase from their respective unfed weights. Electrophysiological recordings of the pharyngeal pump during blood feeding revealed that ticks ingested blood at a rate of 6.1-6.4 suctions per second. Mean blood volume ingested per suction was 0.013 μl in females and 0.007 μl in both males and nymphs. Blood meal size (mg) correlated with unfed body weight (mg) (r(2)=0.50, p<0.05) and with blood volume ingested per suction (r(2)=0.71, p<0.05). Unfed ticks exhibited a circadian ventilation rhythm with discontinuous gas exchange pattern during the daytime and continuous pattern during nighttime. Mean standard metabolic rates (SMR, V̇(CO2)) in unfed nymphs, females and males of 1.4, 3.0 and 0.9 μl h(-1) increased to 2.0, 5.7 and 2.4 μl h(-1), respectively, after a blood meal. SMR correlated positively with blood meal size (r(2)=0.89, p<0.05). Mean coxal fluid weight excreted after a blood meal in nymphs, females, and males was 8.7, 20.0, and 7.7 mg, respectively, which represents 27.0%, 23.4% and 26.7% of their blood meal size. This study revealed biological and physiological characteristics of soft tick blood feeding and metabolism important to tick survival.
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Affiliation(s)
- Hongyuan Zheng
- USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX 78028, USA; Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, China
| | - Andrew Y Li
- USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX 78028, USA.
| | - Pete D Teel
- Texas A&M AgriLife Research, Department of Entomology, Texas A&M University, College Station, TX 77843, USA
| | | | - Janakiram Seshu
- South Texas Center for Emerging Infectious Diseases and Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Jingze Liu
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, China
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