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Rogoll L, Schulz K, Staubach C, Oļševskis E, Seržants M, Lamberga K, Conraths FJ, Sauter-Louis C. Identification of predilection sites for wild boar carcass search based on spatial analysis of Latvian ASF surveillance data. Sci Rep 2024; 14:382. [PMID: 38172492 PMCID: PMC10764341 DOI: 10.1038/s41598-023-50477-7] [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: 05/26/2023] [Accepted: 12/20/2023] [Indexed: 01/05/2024] Open
Abstract
Targeted search for wild boar carcasses is essential for successful control of African swine fever (ASF) in wild boar populations. To examine whether landscape conditions influence the probability of finding ASF-positive carcasses, this study analyzed Global Positioning System (GPS) coordinates of Latvian wild boar carcasses and hunted wild boar, extracted from the CSF/ASF wild boar surveillance database of the European Union, and random coordinates in Latvia. Geographic information system (GIS) software was used to determine the landscape type and landscape composition of carcass detection sites and to measure distances from the carcasses to nearest waterbodies, forest edges, roads and settlements. The results of the automated measurements were validated by manually analyzing a smaller sample. Wild boar carcasses were found predominantly in forested areas and closer to waterbodies and forest edges than random GPS coordinates in Latvia. Carcasses of ASF-infected wild boar were found more frequently in transitional zones between forest and woodland shrub, and at greater distances from roads and settlements compared to ASF-negative carcasses and random points. This leads to the hypothesis, that ASF-infected animals seek shelter in quiet areas further away from human disturbance. A detailed collection of information on the environment surrounding carcass detection sites is needed to characterize predilection sites more accurately.
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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.
| | - Katja Schulz
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Christoph Staubach
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Edvīns Oļševskis
- Food and Veterinary Service, Peldu 30, Riga, 1050, Latvia
- Institute of Food Safety, Animal Health and Environment-"BIOR", Lejupes 3, Riga, 1076, Latvia
| | | | | | - Franz Josef Conraths
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Carola Sauter-Louis
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
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2
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Pepin KM, Borowik T, Frant M, Plis K, Podgórski T. Risk of African swine fever virus transmission among wild boar and domestic pigs in Poland. Front Vet Sci 2023; 10:1295127. [PMID: 38026636 PMCID: PMC10657852 DOI: 10.3389/fvets.2023.1295127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction African swine fever (ASF) is a notifiable disease of swine that impacts global pork trade and food security. In several countries across the globe, the disease persists in wild boar (WB) populations sympatric to domestic pig (DP) operations, with continued detections in both sectors. While there is evidence of spillover and spillback between the sectors, the frequency of occurrence and relative importance of different risk factors for transmission at the wildlife-livestock interface remain unclear. Methods To address this gap, we leveraged ASF surveillance data from WB and DP across Eastern Poland from 2014-2019 in an analysis that quantified the relative importance of different risk factors for explaining variation in each of the ASF surveillance data from WB and DP. Results ASF prevalence exhibited different seasonal trends across the sectors: apparent prevalence was much higher in summer (84% of detections) in DP, but more consistent throughout the year in WB (highest in winter with 45%, lowest in summer at 15%). Only 21.8% of DP-positive surveillance data included surveillance in WB nearby (within 5 km of the grid cell within the last 4 weeks), while 41.9% of WB-positive surveillance samples included any DP surveillance samples nearby. Thus, the surveillance design afforded twice as much opportunity to find DP-positive samples in the recent vicinity of WB-positive samples compared to the opposite, yet the rate of positive WB samples in the recent vicinity of a positive DP sample was 48 times as likely than the rate of positive DP samples in the recent vicinity of a positive WB sample. Our machine learning analyses found that positive samples in WB were predicted by WB-related risk factors, but not to DP-related risk factors. In contrast, WB risk factors were important for predicting detections in DP on a few spatial and temporal scales of data aggregation. Discussion Our results highlight that spillover from WB to DP might be more frequent than the reverse, but that the structure of current surveillance systems challenge quantification of spillover frequency and risk factors. Our results emphasize the importance of, and provide guidance for, improving cross-sector surveillance designs.
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Affiliation(s)
- Kim M. Pepin
- National Wildlife Research Center, USDA, APHIS, Wildlife Services, Fort Collins, CO, United States
| | - Tomasz Borowik
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland
| | - Maciej Frant
- Department of Swine Diseases, National Veterinary Research Institute, Puławy, Poland
| | - Kamila Plis
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland
| | - Tomasz Podgórski
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czechia
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3
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Sykes AL, Galvis JA, O'Hara KC, Corzo C, Machado G. Estimating the effectiveness of control actions on African swine fever transmission in commercial swine populations in the United States. Prev Vet Med 2023; 217:105962. [PMID: 37354739 DOI: 10.1016/j.prevetmed.2023.105962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/23/2023] [Accepted: 06/09/2023] [Indexed: 06/26/2023]
Abstract
Given the proximity of African swine fever (ASF) to the U.S., there is an urgent need to better understand the possible dissemination pathways of the virus within the U.S. swine industry and to evaluate mitigation strategies. Here, we extended PigSpread, a farm-level spatially-explicit stochastic compartmental transmission model incorporating six transmission routes including between-farm swine movements, vehicle movements, and local spread, to model the dissemination of ASF. We then examined the effectiveness of control actions similar to the ASF national response plan. The average number of secondary infections during the first 60 days of the outbreak was 49 finisher farms, 17 nursery farms, 5 sow farms, and less than one farm in other production types. The between-farm movements of swine were the predominant route of ASF transmission with an average contribution of 71.1%, while local spread and movement of vehicles were less critical with average contributions of 14.6% and 14.4%. We demonstrated that the combination of quarantine, depopulation, movement restrictions, contact tracing, and enhanced surveillance, was the most effective mitigation strategy, resulting in an average reduction of 79.0% of secondary cases by day 140 of the outbreak. Implementing these control actions led to a median of 495,619 depopulated animals, 357,789 diagnostic tests, and 54,522 movement permits. Our results suggest that the successful elimination of an ASF outbreak is likely to require the deployment of all control actions listed in the ASF national response plan for more than 140 days, as well as estimating the resources needed for depopulation, testing, and movement permits under these controls.
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Affiliation(s)
- Abagael L Sykes
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA
| | - Jason A Galvis
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA
| | - Kathleen C O'Hara
- US Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Strategy and Policy, Center for Epidemiology and Animal Health, Fort Collins, CO, USA
| | - Cesar Corzo
- Veterinary Population Medicine Department, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - Gustavo Machado
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA.
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4
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Mushagalusa CA, Penrith ML, Etter EMC. Spatiotemporal analysis of African swine fever outbreaks on South African smallholder farms, 1993–2018. J S Afr Vet Assoc 2022; 93:82-88. [DOI: 10.36303/jsava.161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Affiliation(s)
- CA Mushagalusa
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria,
South Africa
- Department of Animal Production, Faculty of Agriculture, Université Evangélique en Afrique,
Democratic Republic of Congo
- Laboratoire de Biomathématiques et d’Estimations Forestières (LABEF), Faculté des Sciences Agronomiques (FSA), Université d’Abomey-Calavi,
Benin
| | - M-L Penrith
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria,
South Africa
| | - EMC Etter
- Department of Production Animal Studies, Faculty of Veterinary Sciences, University of Pretoria,
South Africa
- CIRAD, UMR Animal, Santé, Territoires, Risque et Ecosystèmes (ASTRE), Petit-Bourg, Guadeloupe,
France
- ASTRE, University of Montpellier, CIRAD, INRA, Montpellier,
France
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5
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Baños JV, Boklund A, Gogin A, Gortázar C, Guberti V, Helyes G, Kantere M, Korytarova D, Linden A, Masiulis M, Miteva A, Neghirla I, Oļševskis E, Ostojic S, Petr S, Staubach C, Thulke H, Viltrop A, Wozniakowski G, Broglia A, Abrahantes Cortiñas J, Dhollander S, Mur L, Papanikolaou A, Van der Stede Y, Zancanaro G, Ståhl K. Epidemiological analyses of African swine fever in the European Union: (September 2020 to August 2021). EFSA J 2022; 20:e07290. [PMID: 35515335 PMCID: PMC9066549 DOI: 10.2903/j.efsa.2022.7290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
This report provides a descriptive analysis of the African swine fever (ASF) Genotype II epidemic in the affected Member States in the EU and two neighbouring countries for the period from 1 September 2020 to 31 August 2021. ASF continued to spread in wild boar in the EU, it entered Germany in September 2020, while Belgium became free from ASF in October 2020. No ASF outbreaks in domestic pigs nor cases in wild boar have been reported in Greece since February 2020. In the Baltic States, overall, there has been a declining trend in proportions of polymerase chain reaction (PCR)-positive samples from wild boar carcasses in the last few years. In the other countries, the proportions of PCR-positive wild boar carcasses remained high, indicating continuing spread of the disease. A systematic literature review revealed that the risk factors most frequently significantly associated with ASF in domestic pigs were pig density, low levels of biosecurity and socio-economic factors. For wild boar, most significant risk factors were related to habitat, socio-economic factors and wild boar management. The effectiveness of different control options in the so-named white zones, areas where wild boar densities have been drastically reduced to avoid further spread of ASF after a new introduction, was assessed with a stochastic model. Important findings were that establishing a white zone is much more challenging when the area of ASF incursion is adjacent to an area where limited control measures are in place. Very stringent wild boar population reduction measures in the white zone are key to success. The white zone needs to be far enough away from the affected core area so that the population can be reduced in time before the disease arrives and the timing of this will depend on the wild boar density and the required population reduction target in the white zone. Finally, establishing a proactive white zone along the demarcation line of an affected area requires higher culling efforts, but has a higher chance of success to stop the spread of the disease than establishing reactive white zones after the disease has already entered in the area.
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Amado MEV, Carmo LP, Berezowski J, Fischer C, Santos MJ, Grütter G. Towards risk-based surveillance of African Swine Fever in Switzerland. Prev Vet Med 2022; 204:105661. [DOI: 10.1016/j.prevetmed.2022.105661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 03/14/2022] [Accepted: 04/24/2022] [Indexed: 10/18/2022]
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7
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Malakauskas A, Schulz K, Kukanauskaitė I, Masiulis M, Conraths FJ, Sauter-Louis C. African Swine Fever Outbreaks in Lithuanian Domestic Pigs in 2019. Animals (Basel) 2022; 12:115. [PMID: 35011221 PMCID: PMC8749716 DOI: 10.3390/ani12010115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/24/2021] [Accepted: 12/29/2021] [Indexed: 12/15/2022] Open
Abstract
While numerous risk factors of African swine fever (ASF) transmission to domestic pigs have been described, ASF virus introduction has often not been traced back to one single defined cause. The large number of ASF outbreaks that occurred in domestic pigs in Lithuania from 2014 through to 2018 raised the question regarding whether outbreak-specific risk factors and transmission routes could be identified. Therefore, a prospective matched case-control study was designed. Data from 18 outbreaks that occurred in Lithuanian in 2019 and 36 control farms were analyzed. Conditional multivariable logistic regression showed that two or more visits by veterinary inspection of a farm had a significant preventive effect on the occurrence of ASF on a farm (Odds ratio (OR) 14.21, confidence interval (CI) 1.09-185.60 for farms not inspected vs. farms inspected twice or more a year), while certain practices (e.g., mushroom picking, sharing equipment, etc.), which might facilitate the indirect introduction of ASF from fields and forests into piggeries, significantly increased the odds of an outbreak (OR 5.18, CI 1.10-24.44). The results of the study highlight the importance of veterinary inspections for increasing the biosecurity level on pig farms and the awareness of ASF. The knowledge on potential protective and risk factors may help to improve the prevention and control of ASF outbreaks in domestic pig farms in Lithuania and other affected countries.
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Affiliation(s)
- Alvydas Malakauskas
- Department of Veterinary Pathobiology, Veterinary Academy, Lithuanian University of Health Sciences, Tilžės 18, LT44307 Kaunas, Lithuania;
- State Food and Veterinary Service, Siesiku 19, LT07170 Vilnius, Lithuania;
| | - Katja Schulz
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (K.S.); (F.J.C.); (C.S.-L.)
| | - Indrė Kukanauskaitė
- Department of Veterinary Pathobiology, Veterinary Academy, Lithuanian University of Health Sciences, Tilžės 18, LT44307 Kaunas, Lithuania;
- State Food and Veterinary Service, Siesiku 19, LT07170 Vilnius, Lithuania;
| | - Marius Masiulis
- State Food and Veterinary Service, Siesiku 19, LT07170 Vilnius, Lithuania;
- National Food and Veterinary Risk Assessment Institute, J. Kairiūkščio 10, LT08409 Vilnius, Lithuania
| | - Franz Josef Conraths
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (K.S.); (F.J.C.); (C.S.-L.)
| | - Carola Sauter-Louis
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (K.S.); (F.J.C.); (C.S.-L.)
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8
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Bacigalupo SA, Dixon LK, Gubbins S, Kucharski AJ, Drewe JA. Wild boar visits to commercial pig farms in southwest England: implications for disease transmission. EUR J WILDLIFE RES 2022; 68:69. [PMID: 36213142 PMCID: PMC9532280 DOI: 10.1007/s10344-022-01618-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/30/2022]
Abstract
Contact between wild animals and farmed livestock may result in disease transmission with huge financial, welfare and ethical consequences. Conflicts between people and wildlife can also arise when species such as wild boar (Sus scrofa) consume crops or dig up pasture. This is a relatively recent problem in England where wild boar populations have become re-established in the last 20 years following a 500-year absence. The aim of this pilot study was to determine if and how often free-living wild boar visited two commercial pig farms near the Forest of Dean in southwest England. We placed 20 motion-sensitive camera traps at potential entry points to, and trails surrounding, the perimeter of two farmyards housing domestic pigs between August 2019 and February 2021, covering a total of 6030 trap nights. Forty wild boar detections were recorded on one farm spread across 27 nights, with a median (range) of 1 (0 to 7) night of wild boar activity per calendar month. Most of these wild boar detections occurred between ten and twenty metres of housed domestic pigs. No wild boar was detected at the other farm. These results confirm wild boar do visit commercial pig farms, and therefore, there is potential for contact and pathogen exchange between wild boar and domestic pigs. The visitation rates derived from this study could be used to parameterise disease transmission models of pathogens common to domestic pigs and wild boars, such as the African swine fever virus, and subsequently to develop mitigation strategies to reduce unwanted contacts.
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Affiliation(s)
| | | | | | - Adam J Kucharski
- London School of Hygiene & Tropical Medicine, University of London, London, UK
| | - Julian A Drewe
- Royal Veterinary College, University of London, Hatfield, AL9 7TA UK
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9
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Vithanage M, Mayakaduwage SS, Gunarathne V, Rajapaksha AU, Ahmad M, Abduljabbar A, Usman A, Al-Wabel MI, Ippolito JA, Ok YS. Animal carcass burial management: implications for sustainable biochar use. APPLIED BIOLOGICAL CHEMISTRY 2021; 64:91. [PMID: 34957350 PMCID: PMC8693145 DOI: 10.1186/s13765-021-00652-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 11/16/2021] [Indexed: 06/02/2023]
Abstract
This review focuses on existing technologies for carcass and corpse disposal and potential alternative treatment strategies. Furthermore, key issues related to these treatments (e.g., carcass and corpse disposal events, available methods, performances, and limitations) are addressed in conjunction with associated environmental impacts. Simultaneously, various treatment technologies have been evaluated to provide insights into the adsorptive removal of specific pollutants derived from carcass disposal and management. In this regard, it has been proposed that a low-cost pollutant sorbent may be utilized, namely, biochar. Biochar has demonstrated the ability to remove (in)organic pollutants and excess nutrients from soils and waters; thus, we identify possible biochar uses for soil and water remediation at carcass and corpse disposal sites. To date, however, little emphasis has been placed on potential biochar use to manage such disposal sites. We highlight the need for strategic efforts to accurately assess biochar effectiveness when applied towards the remediation of complex pollutants produced and circulated within carcass and corpse burial systems.
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Affiliation(s)
- Meththika Vithanage
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250 Sri Lanka
| | - S. S. Mayakaduwage
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250 Sri Lanka
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, Australia
| | - Viraj Gunarathne
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250 Sri Lanka
| | - Anushka Upamali Rajapaksha
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250 Sri Lanka
| | - Mahtab Ahmad
- Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320 Pakistan
| | - Adel Abduljabbar
- Industrial Psychology, College of Education, King Saud University, Riyadh, Saudi Arabia
| | - Adel Usman
- Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad I. Al-Wabel
- Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
| | - James A. Ippolito
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO USA
| | - Yong Sik Ok
- Korea Biochar Research Center, APRU Sustainable Waste Management and Division of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841 South Korea
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10
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Sauter-Louis C, Conraths FJ, Probst C, Blohm U, Schulz K, Sehl J, Fischer M, Forth JH, Zani L, Depner K, Mettenleiter TC, Beer M, Blome S. African Swine Fever in Wild Boar in Europe-A Review. Viruses 2021; 13:1717. [PMID: 34578300 PMCID: PMC8472013 DOI: 10.3390/v13091717] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 12/20/2022] Open
Abstract
The introduction of genotype II African swine fever (ASF) virus, presumably from Africa into Georgia in 2007, and its continuous spread through Europe and Asia as a panzootic disease of suids, continues to have a huge socio-economic impact. ASF is characterized by hemorrhagic fever leading to a high case/fatality ratio in pigs. In Europe, wild boar are especially affected. This review summarizes the currently available knowledge on ASF in wild boar in Europe. The current ASF panzootic is characterized by self-sustaining cycles of infection in the wild boar population. Spill-over and spill-back events occur from wild boar to domestic pigs and vice versa. The social structure of wild boar populations and the spatial behavior of the animals, a variety of ASF virus (ASFV) transmission mechanisms and persistence in the environment complicate the modeling of the disease. Control measures focus on the detection and removal of wild boar carcasses, in which ASFV can remain infectious for months. Further measures include the reduction in wild boar density and the limitation of wild boar movements through fences. Using these measures, the Czech Republic and Belgium succeeded in eliminating ASF in their territories, while the disease spread in others. So far, no vaccine is available to protect wild boar or domestic pigs reliably against ASF.
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Affiliation(s)
- Carola Sauter-Louis
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (F.J.C.); (C.P.); (K.S.)
| | - Franz J. Conraths
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (F.J.C.); (C.P.); (K.S.)
| | - Carolina Probst
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (F.J.C.); (C.P.); (K.S.)
| | - Ulrike Blohm
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Immunology, Südufer 10, 17493 Greifswald-Insel Riems, Germany;
| | - Katja Schulz
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (F.J.C.); (C.P.); (K.S.)
| | - Julia Sehl
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany;
| | - Melina Fischer
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Diagnostic Virology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (M.F.); (J.H.F.); (M.B.); (S.B.)
| | - Jan Hendrik Forth
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Diagnostic Virology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (M.F.); (J.H.F.); (M.B.); (S.B.)
| | - Laura Zani
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of International Animal Health/One Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (L.Z.); (K.D.)
| | - Klaus Depner
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of International Animal Health/One Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (L.Z.); (K.D.)
| | - Thomas C. Mettenleiter
- 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, Institute of Diagnostic Virology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (M.F.); (J.H.F.); (M.B.); (S.B.)
| | - Sandra Blome
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Diagnostic Virology, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (M.F.); (J.H.F.); (M.B.); (S.B.)
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11
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Neumann EJ, Hall WF, Dahl J, Hamilton D, Kurian A. Is transportation a risk factor for African swine fever transmission in Australia: a review. Aust Vet J 2021; 99:459-468. [PMID: 34235721 DOI: 10.1111/avj.13106] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 06/08/2021] [Accepted: 06/21/2021] [Indexed: 11/27/2022]
Abstract
African swine fever (ASF) is a viral disease of the pigs that was first described in Africa during the early part of the twentieth century. The disease has periodically occurred outside of Africa, including an ongoing epidemic in Europe and Asia that started in 2007; the disease has never occurred in Australia or New Zealand. Once introduced into a country, spread can occur through direct and indirect routes of transmission. Infected feral pig populations have the potential to act as a long-term reservoir for the virus, making eradication difficult. Just before and throughout the period of clinical signs, ASF virus is shed in oronasal fluids, urine, faeces and blood. This results in contamination of the pig's environment, including flooring, equipment and vehicles. Transportation-related risk factors therefore are likely to play an important role in ASF spread, though evidence thus far has been largely anecdotal. In addition to the existing AUSVETPLAN ASF plan, efforts should be made to improve transportation biosecurity, from the time a pig leaves the farm to its destination. Collection of data that could quantify the capabilities and capacity of Australia to clean and disinfect livestock trucks would help to determine if private and/or public sector investment should be made in this area of biosecurity. No peer-reviewed research was identified that described a specific process for cleaning and disinfecting a livestock truck known to be contaminated with ASF virus, though literature suggests that transportation is an important route of transmission for moving the virus between farms and countries.
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Affiliation(s)
- E J Neumann
- Riddet Institute, Massey University, Tennent Drive, Palmerston North, 4474, New Zealand
| | - W F Hall
- William Hall and Associates, 114 Swan Drive, Googong, New South Wales, 2620, Australia
| | - J Dahl
- Danish Agriculture and Food Council, Axelborg, Copenhagen V, Denmark
| | - D Hamilton
- South Australian Research and Development Institute, South Australia, 5064, Australia
| | - A Kurian
- Epi-Insight Limited, 17 Main South Road, East Taieri, 9024, New Zealand
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12
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Yoo DS, Kim Y, Lee ES, Lim JS, Hong SK, Lee IS, Jung CS, Yoon HC, Wee SH, Pfeiffer DU, Fournié G. Transmission Dynamics of African Swine Fever Virus, South Korea, 2019. Emerg Infect Dis 2021; 27:1909-1918. [PMID: 34152953 PMCID: PMC8237864 DOI: 10.3201/eid2707.204230] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
African swine fever (ASF) is a substantial concern for global food production and security. However, lack of epidemiologic data in affected areas has limited the knowledge of the main drivers of ASF virus (ASFV) transmission. To assess the role of vehicle movements and wild boar populations in spreading ASFV to pig farms in South Korea, we combined data generated by ASF surveillance on pig farms and of wild boars with nationwide global positioning system–based tracking data for vehicles involved in farming activities. Vehicle movements from infected premises were associated with a higher probability of ASFV incursion into a farm than was geographic proximity to ASFV-infected wild boar populations. Although ASFV can spill over from infected wild boars into domestic pigs, vehicles played a substantial role in spreading infection between farms, despite rapid on-farm detection and culling. This finding highlights the need for interventions targeting farm-to-farm and wildlife-to-farm interfaces.
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13
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Pollock LA, Newton EJ, Koen EL. Predicting high-risk areas for African swine fever spread at the wild-domestic pig interface in Ontario. Prev Vet Med 2021; 191:105341. [PMID: 33848740 DOI: 10.1016/j.prevetmed.2021.105341] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 02/15/2021] [Accepted: 03/29/2021] [Indexed: 10/21/2022]
Abstract
The probability of disease transmission among livestock premises via spillover from wildlife vectors depends on interacting ecological, demographic, and behavioural variables. Wild pigs (Sus scrofa) act as vectors and reservoirs of many diseases, including African Swine Fever (ASF), a highly lethal and contagious viral disease that affects both wild and domestic swine. Wild pigs play a significant role in the spread of ASF in geographic locations where the disease is present. Planning and preparedness will ensure that swift action can be taken to control ASF if it is introduced into North America. We used a network to predict the highest risk areas for ASF spread in Ontario, Canada given the distribution of wild pig sightings and other risk factors for wild pig presence and movement on the landscape. We used network nodes to represent the presence of domestic pig farms in a defined area, and we weighted network edges by the probability of ASF virus movement between nodes via movement of wild pigs. Our network models predicted that central Ontario has relatively high network closeness, suggesting that this area has a relatively high risk of virus exposure. These highly connected areas tended to also have the highest domestic pig farm density within a node. Central and eastern Ontario had the highest predicted network betweenness, suggesting that these areas are important for controlling virus flow across the province. We detected 10 communities or clusters within the overall network, where nodes were highly connected locally and relatively less connected to the rest of the network. Predicting areas with a high risk of exposure to the ASF virus due to wild pig movement in Ontario will guide managers on where to focus surveillance for ASF in the wild pig population and where to heighten biosecurity within commercial and backyard pig farms, ensuring that managers are prepared to act quickly to limit spread of ASF if the virus is introduced.
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Affiliation(s)
- Lisa A Pollock
- Trent University, Department of Biology, Peterborough, ON, Canada; Ministry of Natural Resources and Forestry, Wildlife Research and Monitoring Section, Peterborough, ON, Canada
| | - Erica J Newton
- Ministry of Natural Resources and Forestry, Wildlife Research and Monitoring Section, Peterborough, ON, Canada
| | - Erin L Koen
- Trent University, Department of Biology, Peterborough, ON, Canada; Ministry of Natural Resources and Forestry, Wildlife Research and Monitoring Section, Peterborough, ON, Canada.
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14
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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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15
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Kim WH, Bae SH, Cho S. Spatiotemporal Dynamics of Highly Pathogenic Avian Influenza Subtype H5N8 in Poultry Farms, South Korea. Viruses 2021; 13:v13020274. [PMID: 33579009 PMCID: PMC7916766 DOI: 10.3390/v13020274] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/07/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
Highly pathogenic avian influenza (HPAI), a zoonotic disease, is a major threat to humans and poultry health worldwide. In January 2014, HPAI virus subtype H5N8 first infected poultry farms in South Korea, and 393 outbreaks, overall, were reported with enormous economic damage in the poultry industry. We analyzed the spatiotemporal distribution of HPAI H5N8 outbreaks in poultry farms using the global and local spatiotemporal interaction analyses in the first (January to July 2014) and second (September 2014 to June 2015) outbreak waves. The space–time K-function analyses revealed significant interactions within three days and in an over-40 km space–time window between the two study periods. The excess risk attributable value (D0) was maintained despite the distance in the case of HPAI H5N8 in South Korea. Eleven spatiotemporal clusters were identified, and the results showed that the HPAI introduction was from the southwestern region, and spread to the middle region, in South Korea. This spatiotemporal interaction indicates that the HPAI epidemic in South Korea was mostly characterized by short period transmission, regardless of the distance. This finding supports strict control strategies such as preemptive depopulation, and poultry movement tracking. Further studies are needed to understand HPAI disease transmission patterns.
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Affiliation(s)
- Woo-Hyun Kim
- College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea;
| | - Sun Hak Bae
- Department of Geography Education, Kangwon National University, Chuncheon 24341, Korea;
| | - Seongbeom Cho
- College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea;
- Correspondence: ; Tel.: +82-2-880-1270
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16
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Brookes VJ, Barrett TE, Ward MP, Roby JA, Hernandez-Jover M, Cross EM, Donnelly CM, Barnes TS, Wilson CS, Khalfan S. A scoping review of African swine fever virus spread between domestic and free-living pigs. Transbound Emerg Dis 2021; 68:2643-2656. [PMID: 33455062 DOI: 10.1111/tbed.13993] [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: 06/28/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/31/2022]
Abstract
Since 2007, African swine fever virus (ASFV) has spread to countries in Europe, Asia and Oceania and has caused devastating impacts on pigs and the pork industry. Transmission can be direct or indirect, and epidemiologic scenarios have been described in which spread occurs between free-living and domestic pigs. The purpose of this scoping review was to identify primary research in which authors made statements to support ASFV transmission between free-living and domestic pigs and assess the circumstances in which transmission events occurred. A search was conducted in five bibliographic databases and the grey literature. Two reviewers (from a team of ten) independently screened each record and charted data (demographics of the pig populations, their husbandry [domestic pigs] and habitat [free-living pigs], the spatial and temporal distribution of ASF, the occurrence or burden of ASF in the populations, and whether ticks were present in the geographic range of the pig populations). Data synthesis included statistics and a narrative summary. From 1,349 records screened, data were charted from 46 individual studies published from 1985 to 2020. Outbreak investigations revealed that whilst poor biosecurity of domestic pig operations was often reported, direct contact resulting in transmission between free-living and domestic pigs was rarely reported. Studies in which quantitative associations were made generally found that spread within populations was more important than spread between populations, although this was not always the case, particularly when domestic pigs were free-ranging. We conclude that there is limited evidence that transmission of ASFV between free-living and domestic pigs is an important feature of ASF epidemiology, especially in the current ASF epidemic in Europe and the Russian Federation. If ASFV elimination cannot be achieved in free-living pigs, compartmentalization of domestic pig populations from free-living populations via biosecurity strategies could be used to support trade of domestic pigs.
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Affiliation(s)
- Victoria J Brookes
- School of Animal and Veterinary Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia.,Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Wagga Wagga, NSW, Australia
| | - Tamille E Barrett
- School of Animal and Veterinary Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia.,Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Wagga Wagga, NSW, Australia
| | - Michael P Ward
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW, Australia
| | - Justin A Roby
- Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Wagga Wagga, NSW, Australia.,School of Biomedical Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia
| | - Marta Hernandez-Jover
- School of Animal and Veterinary Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia.,Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Wagga Wagga, NSW, Australia
| | - Emily M Cross
- School of Biomedical Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia
| | - Camilla M Donnelly
- School of Biomedical Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia
| | - Tamsin S Barnes
- The University of Queensland, School of Veterinary Science, Gatton, Qld, Australia.,The University of Queensland, Queensland Alliance for Agriculture and Food Innovation, Gatton, Qld, Australia
| | - Cara S Wilson
- School of Animal and Veterinary Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia.,Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Wagga Wagga, NSW, Australia
| | - Shahid Khalfan
- School of Animal and Veterinary Sciences, Faculty of Science, Charles Sturt University, Wagga Wagga, NSW, Australia.,Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Wagga Wagga, NSW, Australia
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17
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Morelle K, Bubnicki J, Churski M, Gryz J, Podgórski T, Kuijper DPJ. Disease-Induced Mortality Outweighs Hunting in Causing Wild Boar Population Crash After African Swine Fever Outbreak. Front Vet Sci 2020; 7:378. [PMID: 32850993 PMCID: PMC7399055 DOI: 10.3389/fvets.2020.00378] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 05/28/2020] [Indexed: 01/02/2023] Open
Abstract
African swine fever (ASF) has been spreading in the Eurasian continent for more than 10 years now. Although the course of ASF in domestic pigs and its negative economic impact on the pork industry are well-known, we still lack a quantitative assessment of the impact of ASF on wild boar (Sus scrofa) populations under natural conditions. Wild boar is not only a reservoir for ASF; it is also one of the key wildlife species affecting structure and functioning of ecosystems. Therefore, knowledge on how ASF affects wild boar populations is crucial to better predict ecosystem response and for the design of scientific-based wild boar management to control ASF. We used a long-term camera trap survey (2012-2017) from the Białowieza Primeval Forest (BPF, Poland), where an ASF outbreak occurred in 2015, to investigate the impact of the disease on wild boar population dynamics under two contrasting management regimes (hunted vs. non-hunted). In the hunted part of BPF ("managed area"), hunting was drastically increased prior and after the first ASF case occurred (March 2015), whereas inside the National Park, hunting was not permitted ("unmanaged area," first detected case in June 2015). Using a random encounter model (REM), we showed that the density and abundance of wild boar dropped by 84 and 95% within 1 year following ASF outbreak in the unmanaged and managed area, respectively. In the managed area, we showed that 11-22% additional mortality could be attributed to hunting. Our study suggests that ASF-induced mortality, by far, outweighs hunting-induced mortality in causing wild boar population decline and shows that intensified hunting in newly ASF-infected areas does not achieve much greater reduction of population size than what is already caused by the ASF virus.
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Affiliation(s)
- Kevin Morelle
- Mammal Research Institute, Polish Academy of Sciences, Białowieza, Poland.,Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czechia
| | - Jakub Bubnicki
- Mammal Research Institute, Polish Academy of Sciences, Białowieza, Poland
| | - Marcin Churski
- Mammal Research Institute, Polish Academy of Sciences, Białowieza, Poland
| | - Jakub Gryz
- Department of Forest Ecology, Forest Research Institute (IBL), Raszyn, Poland
| | - Tomasz Podgórski
- Mammal Research Institute, Polish Academy of Sciences, Białowieza, Poland.,Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czechia
| | - Dries P J Kuijper
- Mammal Research Institute, Polish Academy of Sciences, Białowieza, Poland
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18
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Spatio-Temporal Analysis of the Spread of ASF in the Russian Federation in 2017-2019. ACTA VET-BEOGRAD 2020. [DOI: 10.2478/acve-2020-0014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Currently, African swine fever (ASF) is one of the biggest global economic challenges in Europe and Asia. Despite all the efforts done to understand the mechanism of spread, presence and maintenance of ASF in domestic pigs and wild boar, there are still many gaps in the knowledge on its epidemiology.
This study aims to describe spatial and temporal patterns of ASF spread in wild boar and domestic pigs in the country during the last three years. Methods of Spatio-temporal scanning statistics of Kulldorff (SatScan) and Mann-Kendell statistics (space-time cube) were used to identify potential clusters of outbreaks and the presence of hot spots (areas of active flare clusters), respectively. The results showed that ASF in the country has a local epidemic pattern of spread (11 explicit clusters in wild boar and 16 epizootic clusters were detected in the domestic pig population: 11 in the European part and 5 in the Asian part), and only six of them are overlapped suggesting that ASF epidemics in domestic pigs and wild boar are two separate processes. In the Nizhny Novgorod, Vladimir, Ivanovo, Novgorod, Pskov, Leningrad regions, the clusters identified are characterized as sporadic epidemics clusters, while in the Ulyanovsk region, Primorsky Territory, and the Jewish Autonomous Region the clusters are consistent. Considering the low biosecurity level of pig holdings in the far east and its close economic and cultural connections with China as well as other potential risk factors, it can be expected that the epidemic will be present in the region for a long time. The disease has spread in the country since 2007, and now it is reoccurring in some of the previously affected regions. Outbreaks in the domestic pig sector can be localized easily (no pattern detected), while the presence of the virus in wildlife (several consecutive hot spots detected) hampers its complete eradication. Although the disease has different patterns of spread over the country its driving forces remain the same (human-mediated spread and wild boar domestic-pigs mutual spillover). The results indicate that despite all efforts taken since 2007, the policy of eradication of the disease needs to be reviewed, especially measures in wildlife.
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19
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Bosch J, Barasona JA, Cadenas-Fernández E, Jurado C, Pintore A, Denurra D, Cherchi M, Vicente J, Sánchez-Vizcaíno JM. Retrospective spatial analysis for African swine fever in endemic areas to assess interactions between susceptible host populations. PLoS One 2020; 15:e0233473. [PMID: 32469923 PMCID: PMC7259610 DOI: 10.1371/journal.pone.0233473] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 05/05/2020] [Indexed: 12/21/2022] Open
Abstract
African Swine Fever (ASF) is one of the most complex and significant diseases from a sanitary-economic perspective currently affecting the world's swine-farming industry. ASF has been endemic in Sardinia (Italy) since 1978, and several control and eradication programmes have met with limited success. In this traditional ASF endemic area, there are three susceptible host populations for this virus sharing the same habitat: wild boar, farmed domestic pigs and non-registered free-ranging pigs (known as "brado" animals). The main goal of this study was to determine and predict fine-scale spatial interactions of this multi-host system in relation to the epidemiology of ASF in the main endemic area of Sardinia, Montes-Orgosolo. To this end, simultaneous monitoring of GPS-GSM collared wild boar and free-ranging pigs sightings were performed to predict interaction indexes through latent selection difference functions with environmental, human and farming factors. Regarding epidemiological assessment, the spatial inter-specific interaction indexes obtained here were used to correlate ASF notifications in wild boar and domestic pig farms. Daily movement patterns, home ranges (between 120.7 and 2,622.8 ha) and resource selection of wild boar were obtained for the first time on the island. Overall, our prediction model showed the highest spatial interactions between wild boar and free-ranging pigs in areas close to pig farms. A spatially explicit model was obtained to map inter-specific interaction over the complete ASF-endemic area of the island. Our approach to monitoring interaction indexes may help explain the occurrence of ASF notifications in wild boar and domestic pigs on a fine-spatial scale. These results support the recent and effective eradication measures taken in Sardinia. In addition, this methodology could be extrapolated to apply in the current epidemiological scenarios of ASF in Eurasia, where exist multi-host systems involving free-ranging pigs and wild boar.
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Affiliation(s)
- Jaime Bosch
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary, Complutense University of Madrid, Madrid, Spain
| | - Jose A. Barasona
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary, Complutense University of Madrid, Madrid, Spain
| | - Estefanía Cadenas-Fernández
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary, Complutense University of Madrid, Madrid, Spain
| | - Cristina Jurado
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary, Complutense University of Madrid, Madrid, Spain
| | - Antonio Pintore
- Istituto Zooprofilattico Sperimentale della Sardegna, Sardinia, Italy
| | - Daniele Denurra
- Istituto Zooprofilattico Sperimentale della Sardegna, Sardinia, Italy
| | - Marcella Cherchi
- Istituto Zooprofilattico Sperimentale della Sardegna, Sardinia, Italy
| | - Joaquín Vicente
- Spanish Wildlife Research Institute (IREC) (CSIC-UCLM), Ciudad Real, Spain
| | - Jose M. Sánchez-Vizcaíno
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary, Complutense University of Madrid, Madrid, Spain
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20
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African Swine Fever Virus - The Possible Role of Flies and Other Insects in Virus Transmission. J Vet Res 2020; 64:1-7. [PMID: 32258793 PMCID: PMC7106000 DOI: 10.2478/jvetres-2020-0001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 12/19/2019] [Indexed: 11/21/2022] Open
Abstract
African swine fever (ASF) is an acute viral haemorrhagic disease of pigs and wild boars. It presents a serious threat to pig production worldwide, and since 2007, ASF outbreaks have been recorded in the Caucasus, Eastern Europe, and the Baltic States. In 2014, the disease was detected in Poland. ASF is on the list of notifiable diseases of the World Organisation for Animal Health (OIE). Due to the lack of an available vaccine and treatment, the countermeasures against the disease consist in early detection of the virus in the pig population and control of its spread through the elimination of herds affected by disease outbreaks. Knowledge of the potential vectors of the virus and its persistence in the environment is crucial to prevent further disease spread and to understand the new epidemiology for how it compares to the previous experience in Spain gathered in the 1970s and 1980s.
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21
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Schulz K, Conraths FJ, Blome S, Staubach C, Sauter-Louis C. African Swine Fever: Fast and Furious or Slow and Steady? Viruses 2019; 11:E866. [PMID: 31533266 PMCID: PMC6783890 DOI: 10.3390/v11090866] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/13/2019] [Accepted: 09/14/2019] [Indexed: 11/16/2022] Open
Abstract
Since the introduction of African swine fever (ASF) into Georgia in 2007, the disease has been spreading in an unprecedented way. Many countries that are still free from the disease fear the emergence of ASF in their territory either in domestic pigs or in wild boar. In the past, ASF was often described as being a highly contagious disease with mortality often up to 100%. However, the belief that the disease might enter a naïve population and rapidly affect the entire susceptible population needs to be critically reviewed. The current ASF epidemic in wild boar, but also the course of ASF within outbreaks in domestic pig holdings, suggest a constant, but relatively slow spread. Moreover, the results of several experimental and field studies support the impression that the spread of ASF is not always fast. ASF spread and its speed depend on various factors concerning the host, the virus, and also the environment. Many of these factors and their effects are not fully understood. For this review, we collated published information regarding the spreading speed of ASF and the factors that are deemed to influence the speed of ASF spread and tried to clarify some issues and open questions in this respect.
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Affiliation(s)
- Katja Schulz
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
| | - Franz Josef Conraths
- 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.
| | - Christoph Staubach
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
| | - Carola Sauter-Louis
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
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22
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Morelle K, Jezek M, Licoppe A, Podgorski T. Deathbed choice by ASF-infected wild boar can help find carcasses. Transbound Emerg Dis 2019; 66:1821-1826. [PMID: 31183963 DOI: 10.1111/tbed.13267] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/31/2019] [Accepted: 06/05/2019] [Indexed: 12/20/2022]
Abstract
African swine fever (ASF) is a fatal disease infectious to wild and domesticated suids. This disease entered the European Union in 2014 and recently reached western Europe, with the first cases observed in Belgium in September 2018. Carcasses of ASF-infected wild boar play an important role in the spread and persistence of the virus in the environment. Thus, rapidly finding and removing carcasses is a crucial measure for effective ASF control. Using distribution modelling, we investigated whether the fine-scale distribution of ASF-infected animals can be predicted and support wild boar carcass searches. Our results suggest that ASF-infected wild boar selected deathbeds in cool and moist habitats; thus, deathbed choice was mostly influenced by topographic and water-dependent covariates. Furthermore, we show that in the case of an epidemic, it is important to quickly collect a minimum of 75-100 carcasses with exact locations to build a well-performing and efficient carcass distribution model. The proposed model provides an indication of where carcasses are most likely to be found and can be used as a guide to strategically allocate resources.
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Affiliation(s)
- Kevin Morelle
- Mammal Research Institute, Polish Academy of Sciences, Bialowieza, Poland
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czech Republic
| | - Milos Jezek
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czech Republic
| | - Alain Licoppe
- SPW-DEMNA-DNE, Laboratoire de la Faune Sauvage et de Cynegetique, Gembloux, Belgium
| | - Tomasz Podgorski
- Mammal Research Institute, Polish Academy of Sciences, Bialowieza, Poland
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czech Republic
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23
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Tabak MA, Pedersen K, Miller RS. Detection error influences both temporal seroprevalence predictions and risk factors associations in wildlife disease models. Ecol Evol 2019; 9:10404-10414. [PMID: 31632645 PMCID: PMC6787870 DOI: 10.1002/ece3.5558] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 07/06/2019] [Indexed: 11/08/2022] Open
Abstract
Understanding the prevalence of pathogens in invasive species is essential to guide efforts to prevent transmission to agricultural animals, wildlife, and humans. Pathogen prevalence can be difficult to estimate for wild species due to imperfect sampling and testing (pathogens may not be detected in infected individuals and erroneously detected in individuals that are not infected). The invasive wild pig (Sus scrofa, also referred to as wild boar and feral swine) is one of the most widespread hosts of domestic animal and human pathogens in North America.We developed hierarchical Bayesian models that account for imperfect detection to estimate the seroprevalence of five pathogens (porcine reproductive and respiratory syndrome virus, pseudorabies virus, Influenza A virus in swine, Hepatitis E virus, and Brucella spp.) in wild pigs in the United States using a dataset of over 50,000 samples across nine years. To assess the effect of incorporating detection error in models, we also evaluated models that ignored detection error. Both sets of models included effects of demographic parameters on seroprevalence. We compared our predictions of seroprevalence to 40 published studies, only one of which accounted for imperfect detection.We found a range of seroprevalence among the pathogens with a high seroprevalence of pseudorabies virus, indicating significant risk to livestock and wildlife. Demographics had mostly weak effects, indicating that other variables may have greater effects in predicting seroprevalence.Models that ignored detection error led to different predictions of seroprevalence as well as different inferences on the effects of demographic parameters.Our results highlight the importance of incorporating detection error in models of seroprevalence and demonstrate that ignoring such error may lead to erroneous conclusions about the risk associated with pathogen transmission. When using opportunistic sampling data to model seroprevalence and evaluate risk factors, detection error should be included.
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Affiliation(s)
- Michael A. Tabak
- Center for Epidemiology and Animal HealthUnited States Department of AgricultureFort CollinsColorado
| | - Kerri Pedersen
- Wildlife ServicesUnited States Department of AgricultureRaleighNorth Carolina
| | - Ryan S. Miller
- Center for Epidemiology and Animal HealthUnited States Department of AgricultureFort CollinsColorado
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24
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Barasona JA, Gallardo C, Cadenas-Fernández E, Jurado C, Rivera B, Rodríguez-Bertos A, Arias M, Sánchez-Vizcaíno JM. First Oral Vaccination of Eurasian Wild Boar Against African Swine Fever Virus Genotype II. Front Vet Sci 2019; 6:137. [PMID: 31106218 PMCID: PMC6498142 DOI: 10.3389/fvets.2019.00137] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 04/11/2019] [Indexed: 11/28/2022] Open
Abstract
African swine fever (ASF), the most significant threat to the pig industry worldwide, has spread to more than 55 countries on three continents, and it affects more than 77% of the world swine population. In the European Union, wild boar (Sus scrofa) is the most severely affected host. The main reasons for the unprecedented and constant spread of ASF in Europe are the trade activities, the continuous movement of infected-wild boar populations among regions and the lack of vaccine to prevent ASF infection. In this study, we demonstrate that oral immunization of wild boar with a non-hemadsorbing, attenuated ASF virus of genotype II isolated in Latvia in 2017 (Lv17/WB/Rie1) conferred 92% protection against challenge with a virulent ASF virus isolate (Arm07). This is, to our knowledge, the first report of a promising vaccine against ASF virus in wild boar by oral administration. Further studies should assess the safety of repeated administration and overdose, characterize long-term shedding and verify the genetic stability of the vaccine virus to confirm if Lv17/WB/Rie1 could be used for free-ranging wild boar in ASF control programs.
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Affiliation(s)
- Jose A Barasona
- Animal Health Department, Faculty of Veterinary, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
| | - Carmina Gallardo
- European Union Reference Laboratory for ASF, Centro de Investigación en Sanidad Animal (INIA-CISA), Madrid, Spain
| | - Estefanía Cadenas-Fernández
- Animal Health Department, Faculty of Veterinary, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
| | - Cristina Jurado
- Animal Health Department, Faculty of Veterinary, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
| | - Belén Rivera
- Animal Health Department, Faculty of Veterinary, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
| | - Antonio Rodríguez-Bertos
- Animal Health Department, Faculty of Veterinary, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain.,Department of Animal Medicine and Surgery, Faculty of Veterinary, Complutense University of Madrid, Madrid, Spain
| | - Marisa Arias
- European Union Reference Laboratory for ASF, Centro de Investigación en Sanidad Animal (INIA-CISA), Madrid, Spain
| | - Jose M Sánchez-Vizcaíno
- Animal Health Department, Faculty of Veterinary, VISAVET Health Surveillance Centre, Complutense University of Madrid, Madrid, Spain
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25
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Fekede RJ, van Gils H, Huang L, Wang X. High probability areas for ASF infection in China along the Russian and Korean borders. Transbound Emerg Dis 2019; 66:852-864. [PMID: 30520567 DOI: 10.1111/tbed.13094] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/18/2018] [Accepted: 11/24/2018] [Indexed: 11/27/2022]
Abstract
African swine fever (ASF) is a transcontinental, contagious, fatal virus disease of pig with devastating socioeconomic impacts. Interaction between infected wild boar and domestic pig may spread the virus. The disease is spreading fast from the west of Eurasia towards ASF-free China. Consequently, prediction of the distribution of ASF along the Sino-Russian-Korean borders is urgent. Our area of interest is Northeast China. The reported ASF-locations in 11 contiguous countries from the Baltic to the Russian Federation were extracted from the archive of the World Organization for Animal Health from July 19, 2007 to March 27, 2017. The locational records of the wild boar were obtained from literature. The environmental predictor variables were downloaded from the WorldClim website. Spatial rarefication and pair-wise geographic distance comparison were applied to minimize spatial autocorrelation of presence points. Principal component analysis (PCA) was used to minimize multi-collinearity among predictor variables. We selected the maximum entropy algorithm for spatial modelling of ASF and wild boar separately, combined the wild boar prediction with the domestic pig census in a single map of suids and overlaid the ASF with the suids map. The accuracy of the models was assessed by the AUC. PCA delivered five components accounting for 95.7% of the variance. Spatial autocorrelation was shown to be insignificant for both ASF and wild boar records. The spatial models showed high mean AUC (0.92 and 0.97) combined with low standard deviations (0.003 and 0.006) for ASF and wild boar, respectively. The overlay of the ASF and suids maps suggests that a relatively short sector of the Sino-Russian border has a high probability entry point of ASF at current conditions. Two sectors of the Sino-Korean border present an elevated risk.
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Affiliation(s)
- Regassa Joka Fekede
- Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang province, China.,College of Wildlife Resource, Northeast Forestry University, Harbin, Heilongjiang province, China
| | - Hein van Gils
- Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang province, China.,Department of Geography, Geoinformatics & Meteorology, University of Pretoria, Pretoria, Gauteng Province, South Africa
| | - LiYa Huang
- Changbai Mountain Academy of Sciences, Antu, Jilin province, China
| | - XiaoLong Wang
- Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang province, China.,College of Wildlife Resource, Northeast Forestry University, Harbin, Heilongjiang province, China
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26
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Guinat C, Nicolas G, Vergne T, Bronner A, Durand B, Courcoul A, Gilbert M, Guérin JL, Paul MC. Spatio-temporal patterns of highly pathogenic avian influenza virus subtype H5N8 spread, France, 2016 to 2017. Euro Surveill 2018; 23:1700791. [PMID: 29970219 PMCID: PMC6030875 DOI: 10.2807/1560-7917.es.2018.23.26.1700791] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 03/02/2018] [Indexed: 11/25/2022] Open
Abstract
IntroductionFrance is one of Europe's foremost poultry producers and the world's fifth largest producer of poultry meat. In November 2016, highly pathogenic avian influenza (HPAI) virus subtype H5N8 emerged in poultry in the country. As of 23 March 2017, a total of 484 confirmed outbreaks were reported, with consequences on animal health and socio-economic impacts for producers. Methods: We examined the spatio-temporal distribution of outbreaks that occurred in France between November 2016 and March 2017, using the space-time K-function and space-time permutation model of the scan statistic test. Results: Most outbreaks affected duck flocks in south-west France. A significant space-time interaction of outbreaks was present at the beginning of the epidemic within a window of 8 km and 13 days. This interaction disappeared towards the epidemic end. Five spatio-temporal outbreak clusters were identified in the main poultry producing areas, moving sequentially from east to west. The average spread rate of the epidemic front wave was estimated to be 5.5 km/week. It increased from February 2017 and was negatively associated with the duck holding density. Conclusion: HPAI-H5N8 infections varied over time and space in France. Intense transmission events occurred at the early stages of the epidemic, followed by long-range jumps in the disease spread towards its end. Findings support strict control strategies in poultry production as well as the maintenance of high biosecurity standards for poultry holdings. Factors and mechanisms driving HPAI spread need to be further investigated.
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Affiliation(s)
- Claire Guinat
- École Nationale Vétérinaire de Toulouse, Toulouse, France
- Institut National de la Recherche Agronomique, Toulouse, France
| | - Gaëlle Nicolas
- Université Libre de Bruxelles, Brussels, Belgium
- These authors contributed equally to this work
| | - Timothée Vergne
- These authors contributed equally to this work
- Institut de Recherche pour le Développement, Montpellier, France
| | - Anne Bronner
- Direction Générale de l'Alimentation, Paris, France
| | - Benoit Durand
- Agence Nationale de Sécurité Sanitaire de l'Alimentation, Maisons-Alfort, France
| | - Aurélie Courcoul
- Agence Nationale de Sécurité Sanitaire de l'Alimentation, Maisons-Alfort, France
| | - Marius Gilbert
- Université Libre de Bruxelles, Brussels, Belgium
- Fonds National de la Recherche Scientifique, Brussels, Belgium
| | - Jean-Luc Guérin
- École Nationale Vétérinaire de Toulouse, Toulouse, France
- Institut National de la Recherche Agronomique, Toulouse, France
| | - Mathilde C Paul
- École Nationale Vétérinaire de Toulouse, Toulouse, France
- Institut National de la Recherche Agronomique, Toulouse, France
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27
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Jurado C, Martínez-Avilés M, De La Torre A, Štukelj M, de Carvalho Ferreira HC, Cerioli M, Sánchez-Vizcaíno JM, Bellini S. Relevant Measures to Prevent the Spread of African Swine Fever in the European Union Domestic Pig Sector. Front Vet Sci 2018; 5:77. [PMID: 29713637 PMCID: PMC5912175 DOI: 10.3389/fvets.2018.00077] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 03/26/2018] [Indexed: 12/30/2022] Open
Abstract
During the past decade, African swine fever (ASF) has spread from the Caucasus region to eastern European Union countries affecting domestic pig and wild boar populations. In order to avert ASF spread, mitigation measures targeting both populations have been established. However, despite these efforts, ASF has been reported in thirteen different countries (Georgia, Azerbaijan, Armenia, the Russian Federation, Ukraine, Belarus, Estonia, Latvia, Lithuania, Poland, Moldova, Czech Republic, and Romania). In the absence of an effective vaccine or treatment to ASF, introduction and spread of ASF onto domestic pig farms can only be prevented by strict compliance to control measures. This study systematically reviewed available measures to prevent the spread of ASF in the EU domestic pig sector distinguishing between commercial, non-commercial, and outdoor farms. The search was performed in PubMed and using a common browser. A total of 52 documents were selected for the final review process, which included scientific articles, reports, EU documents and official recommendations, among others. From this literature review, 37 measures were identified as preventive measures for the introduction and spread of ASF. Subsequently, these measures were assessed by ASF experts for their relevance in the mitigation of ASF spread on the three mentioned types of farms. All experts agreed that some of the important preventive measures for all three types of farms were: the identification of animals and farm records; strict enforcement of the ban on swill feeding; and containment of pigs, so as to not allow direct or indirect pig–pig and/or pig–wild boar contacts. Other important preventive measures for all farms were education of farmers, workers, and operators; no contact between farmers and farm staff and external pigs; appropriate removal of carcasses, slaughter residues, and food waste; proper disposal of manure and dead animals, and abstaining from hunting activities during the previous 48 h (allowing a 48 h interval between hunting and being in contact with domestic pigs). Finally, all experts identified that the important preventive measures for non-commercial and outdoor farms is to improve access of those farms to veterinarians and health services.
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Affiliation(s)
- Cristina Jurado
- VISAVET Health Surveillance Centre, Animal Health Department, Veterinary Faculty, Complutense University of Madrid, Madrid, Spain
| | - Marta Martínez-Avilés
- Animal Health Research Centre, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Madrid, Spain
| | - Ana De La Torre
- Animal Health Research Centre, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Madrid, Spain
| | - Marina Štukelj
- Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia
| | | | - Monica Cerioli
- Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia Romagna (IZSLER), Brescia, Italy
| | - José Manuel Sánchez-Vizcaíno
- VISAVET Health Surveillance Centre, Animal Health Department, Veterinary Faculty, Complutense University of Madrid, Madrid, Spain
| | - Silvia Bellini
- Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia Romagna (IZSLER), Brescia, Italy
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28
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Sánchez-Cordón PJ, Montoya M, Reis AL, Dixon LK. African swine fever: A re-emerging viral disease threatening the global pig industry. Vet J 2018; 233:41-48. [PMID: 29486878 PMCID: PMC5844645 DOI: 10.1016/j.tvjl.2017.12.025] [Citation(s) in RCA: 262] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 09/08/2017] [Accepted: 12/30/2017] [Indexed: 12/28/2022]
Abstract
African swine fever (ASF) recently has spread beyond sub-Saharan Africa to the Trans-Caucasus region, parts of the Russian Federation and Eastern Europe. In this new epidemiological scenario, the disease has similarities, but also important differences, compared to the situation in Africa, including the substantial involvement of wild boar. A better understanding of this new situation will enable better control and prevent further spread of disease. In this article, these different scenarios are compared, and recent information on the pathogenesis of ASF virus strains, the immune response to infection and prospects for developing vaccines is presented. Knowledge gaps and the prospects for future control are discussed.
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Affiliation(s)
| | - M Montoya
- The Pirbright Institute, Pirbright, Woking, Surrey GU24 0NF, UK
| | - A L Reis
- The Pirbright Institute, Pirbright, Woking, Surrey GU24 0NF, UK
| | - L K Dixon
- The Pirbright Institute, Pirbright, Woking, Surrey GU24 0NF, UK.
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29
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Arias M, Jurado C, Gallardo C, Fernández-Pinero J, Sánchez-Vizcaíno JM. Gaps in African swine fever: Analysis and priorities. Transbound Emerg Dis 2017; 65 Suppl 1:235-247. [PMID: 28941208 DOI: 10.1111/tbed.12695] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Indexed: 11/29/2022]
Abstract
African swine fever (ASF) causes greater sanitary, social and economic impacts on swine herds than many other swine diseases. Although ASF was first described in 1921 and it has affected more than fifty countries in Africa, Europe and South America, several key issues about its pathogenesis, immune evasion and epidemiology remain uncertain. This article reviews the main characteristics of the causative virus, its molecular epidemiology, natural hosts, clinical features, epidemiology and control worldwide. It also identifies and prioritizes gaps in ASF from a horizontal point of view encompassing fields including molecular biology, epidemiology, prevention, diagnosis and vaccine development. The purpose of this review is to promote ASF research and enhance its control.
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Affiliation(s)
- M Arias
- Centro de Investigación en Sanidad Animal (CISA-INIA), Madrid, Spain
| | - C Jurado
- VISAVET Center and Animal Health Department, Universidad Complutense de Madrid, Madrid, Spain
| | - C Gallardo
- Centro de Investigación en Sanidad Animal (CISA-INIA), Madrid, Spain
| | | | - J M Sánchez-Vizcaíno
- VISAVET Center and Animal Health Department, Universidad Complutense de Madrid, Madrid, Spain
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30
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Mur L, Sánchez-Vizcaíno JM, Fernández-Carrión E, Jurado C, Rolesu S, Feliziani F, Laddomada A, Martínez-López B. Understanding African Swine Fever infection dynamics in Sardinia using a spatially explicit transmission model in domestic pig farms. Transbound Emerg Dis 2017; 65:123-134. [PMID: 28296281 DOI: 10.1111/tbed.12636] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Indexed: 01/08/2023]
Abstract
African swine fever virus (ASFV) has been endemic in Sardinia since 1978, resulting in severe losses for local pig producers and creating important problems for the island's veterinary authorities. This study used a spatially explicit stochastic transmission model followed by two regression models to investigate the dynamics of ASFV spread amongst domestic pig farms, to identify geographic areas at highest risk and determine the role of different susceptible pig populations (registered domestic pigs, non-registered domestic pigs [brado] and wild boar) in ASF occurrence. We simulated transmission within and between farms using an adapted version of the previously described model known as Be-FAST. Results from the model revealed a generally low diffusion of ASF in Sardinia, with only 24% of the simulations resulting in disease spread, and for each simulated outbreak on average only four farms and 66 pigs were affected. Overall, local spread (indirect transmission between farms within a 2 km radius through fomites) was the most common route of transmission, being responsible for 98.6% of secondary cases. The risk of ASF occurrence for each domestic pig farm was estimated from the spread model results and integrated in two regression models together with available data for brado and wild boar populations. There was a significant association between the density of all three populations (domestic pigs, brado, and wild boar) and ASF occurrence in Sardinia. The most significant risk factors were the high densities of brado (OR = 2.2) and wild boar (OR = 2.1). The results of both analyses demonstrated that ASF epidemiology and infection dynamics in Sardinia create a complex and multifactorial disease situation, where all susceptible populations play an important role. To stop ASF transmission in Sardinia, three main factors (improving biosecurity on domestic pig farms, eliminating brado practices and better management of wild boars) need to be addressed.
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Affiliation(s)
- L Mur
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - J M Sánchez-Vizcaíno
- VISAVET Center and Animal Health Department, Veterinary School, Complutense University of Madrid, Madrid, Spain
| | - E Fernández-Carrión
- VISAVET Center and Animal Health Department, Veterinary School, Complutense University of Madrid, Madrid, Spain
| | - C Jurado
- VISAVET Center and Animal Health Department, Veterinary School, Complutense University of Madrid, Madrid, Spain
| | - S Rolesu
- IZS della Sardegna, Centro di Sorveglianza Epidemiologica, Cagliari, Italy
| | | | - A Laddomada
- IZS della Sardegna, Centro di Sorveglianza Epidemiologica, Cagliari, Italy
| | - B Martínez-López
- Center for Animal Disease Modeling and Surveillance (CADMS), University of California Davis, Davis, CA, USA
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31
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Korennoy FI, Gulenkin VM, Gogin AE, Vergne T, Karaulov AK. Estimating the Basic Reproductive Number for African Swine Fever Using the Ukrainian Historical Epidemic of 1977. Transbound Emerg Dis 2016; 64:1858-1866. [PMID: 27667658 DOI: 10.1111/tbed.12583] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Indexed: 11/30/2022]
Abstract
In 1977, Ukraine experienced a local epidemic of African swine fever (ASF) in the Odessa region. A total of 20 settlements were affected during the course of the epidemic, including both large farms and backyard households. Thanks to timely interventions, the virus circulation was successfully eradicated within 6 months, leading to no additional outbreaks. Detailed report of the outbreak's investigation has been publically available from 2014. The report contains some quantitative data that allow studying the ASF-spread dynamics in the course of the epidemic. In our study, we used this historical epidemic to estimate the basic reproductive number of the ASF virus both within and between farms. The basic reproductive number (R0 ) represents the average number of secondary infections caused by one infectious unit during its infectious period in a susceptible population. Calculations were made under assumption of an exponential initial growth by fitting the approximating curve to the initial segments of the epidemic curves. The R0 both within farm and between farms was estimated at 7.46 (95% confidence interval: 5.68-9.21) and 1.65 (1.42-1.88), respectively. Corresponding daily transmission rates were estimated at 1.07 (0.81-1.32) and 0.09 (0.07-0.10). These estimations based on historical data are consistent with those using data generated by the recent epidemic currently affecting eastern Europe. Such results contribute to the published knowledge on the ASF transmission dynamics under natural conditions and could be used to model and predict the spread of ASF in affected and non-affected regions and to evaluate the effectiveness of different control measures.
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Affiliation(s)
- F I Korennoy
- Federal Center for Animal Health (FGBI ARRIAH), Vladimir, Russia
| | - V M Gulenkin
- Federal Center for Animal Health (FGBI ARRIAH), Vladimir, Russia
| | - A E Gogin
- National Research Institute for Veterinary Virology and Microbiology of Russia (SSINRRIVV&M), Pokrov, Russia
| | - T Vergne
- Royal Veterinary College, University of London, London, UK
| | - A K Karaulov
- Federal Center for Animal Health (FGBI ARRIAH), Vladimir, Russia
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32
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Bosch J, Iglesias I, Muñoz MJ, de la Torre A. A Cartographic Tool for Managing African Swine Fever in Eurasia: Mapping Wild Boar Distribution Based on the Quality of Available Habitats. Transbound Emerg Dis 2016; 64:1720-1733. [PMID: 27596983 DOI: 10.1111/tbed.12559] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Indexed: 11/28/2022]
Abstract
The current African swine fever (ASF) epidemic in Eurasia represents a risk for the swine industry with devastating socio-economic and political consequences. Wild boar appears to be a key factor in maintaining the disease in endemic areas (mainly the Russian Federation) and spreading the disease across borders, including within the European Union. To help predict and interpret the dynamics of ASF infection, we developed a standardized distribution map based on global land cover vegetation (GLOBCOVER) that quantifies the quality of available habitats (QAH) for wild boar across Eurasia as an indirect index for quantifying numbers of wild boar. QAHs were estimated using a seven-level scale based on expert opinion and found to correlate closely with georeferenced presence of wild boar (n = 22 362): the highest wild boar densities (74.47%) were found in areas at the two highest QAH levels, while the lowest densities (5.66%) were found in areas at the lowest QAH levels. Mapping notifications from 2007 to 2016 onto the QAH map showed that in endemic areas, 60% of ASF notifications occurred in domestic pigs, mostly in agricultural landscapes (QAHs 1.75 and 1) containing low-biosecurity domestic pig farms. In the EU, in contrast, 95% of ASF notifications occurred in wild boar, within natural landscapes (QAH 2). These results suggest that the QAH map can be a useful epi-tool for defining risk scenarios and identifying potential travel corridors for ASF. This tool will help inform resource allocation decisions and improve prevention, control and surveillance of ASF and potentially of other diseases affecting swine and wild boar in Eurasia.
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Affiliation(s)
- J Bosch
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (CISA-INIA), Valdeolmos, Madrid, Spain
| | - I Iglesias
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (CISA-INIA), Valdeolmos, Madrid, Spain
| | - M J Muñoz
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (CISA-INIA), Valdeolmos, Madrid, Spain
| | - A de la Torre
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (CISA-INIA), Valdeolmos, Madrid, Spain
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33
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Bosch J, Rodríguez A, Iglesias I, Muñoz MJ, Jurado C, Sánchez-Vizcaíno JM, de la Torre A. Update on the Risk of Introduction of African Swine Fever by Wild Boar into Disease-Free European Union Countries. Transbound Emerg Dis 2016; 64:1424-1432. [PMID: 27354186 DOI: 10.1111/tbed.12527] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Indexed: 11/26/2022]
Abstract
Despite efforts to prevent the appearance and spread of African swine fever (ASF) in the European Union, several Member States are now affected (Lithuania, Poland, Latvia and Estonia). Disease appearance in 2014 was associated with multiple entrances linked to wild boar movement from endemic areas (EFSA Journal, 8, 2015, 1556), but the risk of new introductions remains high (Gallardo et al., Porcine Health Management, 1, and 21) as ASF continues to be active in endemic countries (Russian Federation, Belarus and Ukraine). Since 2014, the number of ASF notifications has increased substantially, particularly in wild boar (WB), in parallel with slow but constant geographical advance of the disease. This situation suggests a real risk of further disease spread into other Member States, posing a great threat to pig production in the EU. Following the principles of the risk-based veterinary surveillance, this article applies a methodology developed by De la Torre et al. (Transboundary and Emerging Diseases, 62, and 272) to assess the relative risk of new introductions of ASF by natural movements of WB according to the current epidemiological situation. This update incorporates the most recent available data and an improved version of the most important risk estimator: an optimized cartographic tool of WB distribution to analyse wild boar suitable habitat. The highest relative risk values were estimated for Slovakia (5) and Romania (5), followed by Finland (4), Czech Republic (3) and Germany (3). Relative risk for Romania and Finland is associated mainly with disease entrance from endemic areas such as the Russian Federation and Ukraine, where the disease is currently spreading; relative risk for Germany and Czech Republic is associated mainly with the potential progress of the disease through the EU, and relative risk for Slovakia is associated with both pathways. WB habitat is the most important risk estimator, whereas WB density is the least significant, suggesting that WB presence is more relevant than density. These results can provide actionable advice for dealing with risk. They can be directly used to inform risk-based national strategies and identify countries that may need to pay greater attention to surveillance or conduct additional evaluations at the subnational level.
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Affiliation(s)
- J Bosch
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Madrid, Spain
| | - A Rodríguez
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Madrid, Spain
| | - I Iglesias
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Madrid, Spain
| | - M J Muñoz
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Madrid, Spain
| | - C Jurado
- Center VISAVET and Animal Health Department, Universidad Complutense de Madrid, Madrid, Spain
| | - J M Sánchez-Vizcaíno
- Center VISAVET and Animal Health Department, Universidad Complutense de Madrid, Madrid, Spain
| | - A de la Torre
- Animal Health Research Center, National Institute for Agricultural and Food Research and Technology (INIA-CISA), Madrid, Spain
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Vergne T, Korennoy F, Combelles L, Gogin A, Pfeiffer DU. Modelling African swine fever presence and reported abundance in the Russian Federation using national surveillance data from 2007 to 2014. Spat Spatiotemporal Epidemiol 2016; 19:70-77. [PMID: 27839582 DOI: 10.1016/j.sste.2016.06.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 06/02/2016] [Accepted: 06/03/2016] [Indexed: 12/27/2022]
Abstract
African swine fever (ASF) is a viral disease of swine that has been present in the Russian Federation since 2007. Counts of ASF outbreaks reported in the Southern regions of the country (2007-2014) were aggregated to a grid of hexagons, and a zero-inflated Poisson model accounting for spatial dependence between hexagons was used to identify factors associated with the presence of ASF outbreaks and factors associated with the number of ASF reports in affected hexagons. Increasing density of pigs raised on low biosecurity farms was found to be positively associated with the probability of occurrence of at least one ASF outbreak in a hexagon and with the average number of reported ASF outbreaks amongst affected hexagons. Increasing human population density and increasing distance from the closest diagnostic laboratory were additional variables associated with number of reported ASF outbreaks amongst affected hexagons. The model was shown to have good predictive ability.
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Affiliation(s)
- Timothée Vergne
- Veterinary Epidemiology, Economics and Public Health group, Royal Veterinary College, London, United Kingdom.
| | - Fedor Korennoy
- FGBI Federal Center for Animal Health (FGBI ARRIAH), Vladimir, Russia
| | - Lisa Combelles
- Veterinary Epidemiology, Economics and Public Health group, Royal Veterinary College, London, United Kingdom
| | - Andrey Gogin
- National Research Institute for Veterinary Virology and Microbiology Russian Academy of Agricultural Science, Pokrov, Russia
| | - Dirk U Pfeiffer
- Veterinary Epidemiology, Economics and Public Health group, Royal Veterinary College, London, United Kingdom
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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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Halasa T, Boklund A, Bøtner A, Toft N, Thulke HH. Simulation of Spread of African Swine Fever, Including the Effects of Residues from Dead Animals. Front Vet Sci 2016; 3:6. [PMID: 26870740 PMCID: PMC4735426 DOI: 10.3389/fvets.2016.00006] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 01/18/2016] [Indexed: 11/19/2022] Open
Abstract
To study the spread of African swine fever (ASF) within a pig unit and the impact of unit size on ASF spread, a simulation model was created. In the model, an animal can be in one of the following stages: susceptible, latent, subclinical, clinical, or recovered. Animals can be infectious during the subclinical stage and are fully infectious during the clinical stage. ASF virus (ASFV) infection through residues of dead animals in the slurries was also modeled in an exponentially fading-out pattern. Low and high transmission rates for ASFV were tested in the model. Robustness analysis was carried out in order to study the impact of uncertain parameters on model predictions. The results showed that the disease may fade out within the pig unit without a major outbreak. Furthermore, they showed that spread of ASFV is dependent on the infectiousness of subclinical animals and the residues of dead animals, the transmission rate of the virus, and importantly the unit size. Moreover, increasing the duration of the latent or the subclinical stages resulted in longer time to disease fade out. The proposed model is a simple and robust tool simulating the spread of ASFV within a pig house taking into account dynamics of ASFV spread and the unit size. The tool can be implemented in simulation models of ASFV spread between herds.
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Affiliation(s)
- Tariq Halasa
- National Veterinary Institute, Technical University of Denmark , Copenhagen , Denmark
| | - Anette Boklund
- National Veterinary Institute, Technical University of Denmark , Copenhagen , Denmark
| | - Anette Bøtner
- National Veterinary Institute, Technical University of Denmark , Copenhagen , Denmark
| | - Nils Toft
- National Veterinary Institute, Technical University of Denmark , Copenhagen , Denmark
| | - Hans-Hermann Thulke
- Department of Ecological Modeling, Helmholtz Center for Environmental Research (UFZ) , Leipzig , Germany
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