1
|
Balmoș OM, Ionică AM, Horvath C, Supeanu A, Moțiu M, Ancuceanu BC, Tamba P, Bărbuceanu F, Cotuțiu V, Coroian M, Dhollander S, Mihalca AD. African swine fever virus DNA is present in non-biting flies collected from outbreak farms in Romania. Parasit Vectors 2024; 17:278. [PMID: 38943218 PMCID: PMC11212390 DOI: 10.1186/s13071-024-06346-x] [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: 04/08/2024] [Accepted: 06/07/2024] [Indexed: 07/01/2024] Open
Abstract
BACKGROUND African swine fever (ASF) is a highly contagious and severe haemorrhagic disease of Suidae, with mortalities that approach 100 percent. Several studies suggested the potential implication of non-biting dipterans in the spread of ASFV in pig farms due to the identification of the ASFV DNA. However, to our knowledge, no study has evaluated the viral DNA load in non-biting dipterans collected in outbreak farms and no risk factors have been analysed. In this context, our study aimed to analyse the risk factors associated with the presence of non-biting dipterans collected from ASF outbreaks in relation to the presence and load of viral DNA. METHODS Backyard farms (BF), type A farms (TAF), and commercial farms (CF), were targeted for sampling in 2020. In 2021, no BF were sampled. Each farm was sampled only once. The identification of the collected flies to family, genus, or species level was performed based on morphological characteristics using specific keys and descriptions. Pools were made prior to DNA extraction. All extracted DNA was tested for the presence of the ASFV using a real-time PCR protocol. For this study, we considered every sample with a CT value of 40 as positive. The statistical analysis was performed using Epi Info 7 software (CDC, USA). RESULTS All collected non-biting flies belonged to five families: Calliphoridae, Sarcophagidae, Fanniidae, Drosophilidae, and Muscidae. Of the 361 pools, 201 were positive for the presence of ASFV DNA. The obtained CT values of the positive samples ranged from 21.54 to 39.63, with a median value of 33.59 and a mean value of 33.56. Significantly lower CT values (corresponding to higher viral DNA load) were obtained in Sarcophagidae, with a mean value of 32.56; a significantly higher number of positive pools were noticed in August, mean value = 33.12. CONCLUSIONS Our study brings compelling evidence of the presence of the most common synanthropic flies near domestic pig farms carrying ASFV DNA, highlighting the importance of strengthening the biosecurity measures and protocols for prevention of the insect life cycle and distribution.
Collapse
Affiliation(s)
- Oana Maria Balmoș
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Calea Mănăștur 3-5, 400372, Cluj-Napoca-Napoca, Romania.
| | - Angela Monica Ionică
- Clinical Hospital of Infectious Diseases of Cluj-Napoca, Strada Iuliu Moldovan 23, 400348, Cluj-Napoca-Napoca, Romania
| | - Cintia Horvath
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Calea Mănăștur 3-5, 400372, Cluj-Napoca-Napoca, Romania
| | - Alexandru Supeanu
- National Sanitary Veterinary and Food Safety Authority, Piața Presei Libere 1, Corp D1, Sector 1, 013701, Bucharest, Romania
| | - Monica Moțiu
- Institute for Diagnosis and Animal Health, Strada Dr. Staicovici 63, Sector 5, 050557, Bucharest, Romania
| | - Beatris Corina Ancuceanu
- Institute for Diagnosis and Animal Health, Strada Dr. Staicovici 63, Sector 5, 050557, Bucharest, Romania
| | - Paula Tamba
- Institute for Diagnosis and Animal Health, Strada Dr. Staicovici 63, Sector 5, 050557, Bucharest, Romania
- Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Splaiul Independentei 105, Bucharest, 050097, Romania
| | - Florica Bărbuceanu
- Institute for Diagnosis and Animal Health, Strada Dr. Staicovici 63, Sector 5, 050557, Bucharest, Romania
- Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Splaiul Independentei 105, Bucharest, 050097, Romania
| | - Vlad Cotuțiu
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Calea Mănăștur 3-5, 400372, Cluj-Napoca-Napoca, Romania
| | - Mircea Coroian
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Calea Mănăștur 3-5, 400372, Cluj-Napoca-Napoca, Romania
| | - Sofie Dhollander
- European Food Safety Authority, Via Carlo Magno 1A, 43126, Parma, Italy
| | - Andrei Daniel Mihalca
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Calea Mănăștur 3-5, 400372, Cluj-Napoca-Napoca, Romania
| |
Collapse
|
2
|
Three Years of African Swine Fever in South Korea (2019–2021): A Scoping Review of Epidemiological Understanding. Transbound Emerg Dis 2023. [DOI: 10.1155/2023/4686980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
African swine fever (ASF) is a highly contagious viral disease in domestic pigs and wild boar that causes tremendous socioeconomic damage in related industries. In 2019, the virus emerged in South Korea, which has since reported 21 outbreaks in domestic pig farms and over 2,600 cases in wild boar. In this review, we synthesize the epidemiological knowledge generated on ASF in South Korea during the first three years of the epidemic (2019–2021). We searched four international and one domestic Korean database to identify scientific articles published since 2019 and describing ASF epidemiology in South Korea. Fourteen articles met our selection criteria and were used to synthesize the origin of ASF in South Korea, the risk factors of disease occurrence, the effectiveness of the surveillance and intervention measures that were implemented, and the viral transmission dynamics. We found that timely intensive surveillance and interventions on domestic pig farms successfully blocked between-farm transmission. However, in wild boar, the ASF virus has spread massively towards the south primarily along the mountain ranges despite ongoing fence erection and intensive depopulation efforts, endangering domestic pig farms across the country. The current devastating epidemic is suspected to be the consequence of an ASF control strategy unaligned to the epidemiological context, the challenging implementation of control measures hindered by topological complexities, and inappropriate biosecurity by field workers. To improve our understanding of ASF epidemiology in South Korea and enhance disease management, future research studies should specify the ecological drivers of disease distribution and spread and devise effective control strategies, particularly in relation to Korean topography, and the latent spread of the virus in wild boar populations. Additionally, research studies should explore the psychosocial factors for ASF management, and develop tools to support evidence-based decision-making for managing ASFV in wild boar.
Collapse
|
3
|
African Swine Fever Virus Load in Hematophagous Dipterans Collected in an Outbreak from Romania: Risk Factors and Implications. Transbound Emerg Dis 2023. [DOI: 10.1155/2023/3548109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
African swine fever (ASF) is a contagious viral disease of swine that causes significant economic damage. The summer peaks and river courses have triggered the hypothesis that vectors may be involved in the transmission of the virus. In temperate climates, insect numbers increase in the late summer. Low temperatures and frosts decrease the number of active insects. Their presence is strongly associated with the nearby wetlands or swamps around the farms. The aim of our study was to evaluate the risk factors associated with the presence of ASFV DNA in hematophagous dipterans and to analyze the relevance of Ct values obtained following RT-PCR analysis of the positive samples in ASF outbreaks in Romania, as an indication for the viral load. The current study included 99 pools of stable flies (Stomoxys calcitrans) and 296 pools of biting midges (Culicoides spp.), collected in June-September 2020, from 30 outbreaks of ASF in domestic swine from backyard farms (BF), type A farms (TAF), and commercial farms (CF). All extracted DNA was tested for the presence of the ASFV genome using a real-time PCR protocol. Ct values of 39.53 and below were considered as positive (min: 18.19; median: 31.41; max: 39.53). The blood meal source was identified in the hematophagous insects by using a PCR protocol targeting the mitochondrial gene cytochrome c oxidase subunit 1. Data were analyzed using R software v. 4.0.5. In total, 3,158 insects (S. calcitrans n = 198 and Culicoides n = 2960) were collected in 23 farms of the 30 outbreak farms. Ten species of biting midges were identified. The total number of insect pools showed significant differences according to the month of sampling, with a higher number of pools collected in August and September. Overall, 137 pools out of the 395 examined were positive for the presence of ASFV DNA. There was a higher viral DNA load in farms where pigs were present at the moment of sampling compared to farms where pigs were already culled, in S. calcitrans compared to Culicoides spp. and in CF and TAF compared to BF.
Collapse
|
4
|
Wang S, Shen H, Lin Q, Huang J, Zhang C, Liu Z, Sun M, Zhang J, Liao M, Li Y, Zhang J. Development of a Cleaved Probe-Based Loop-Mediated Isothermal Amplification Assay for Rapid Detection of African Swine Fever Virus. Front Cell Infect Microbiol 2022; 12:884430. [PMID: 35719327 PMCID: PMC9204333 DOI: 10.3389/fcimb.2022.884430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 04/25/2022] [Indexed: 11/21/2022] Open
Abstract
African Swine Fever (ASF), caused by African swine fever virus (ASFV), is a highly contagious and lethal viral disease of pigs. However, commercial vaccines are not yet available, and neither are drugs to prevent or control ASF. Therefore, rapid, accurate on-site diagnosis is urgently needed for detection during the early stages of ASFV infection. Herein, a cleaved probe-based loop-mediated isothermal amplification (CP-LAMP) detection method was established. Based on the original primer sets, we targeted the ASFV 9GL gene sequence to design a probe harboring a ribonucleotide insertion. Ribonuclease H2 (RNase H2) enzyme activity can only be activated when the probe is perfectly complementary, resulting in hydrolytic release of a quencher moiety, and consequent signal amplification. The method displayed robust sensitivity, with copy number detection as low as 13 copies/µL within 40 min at constant temperature (62°C). Visualization of the fluorescence product was employed using a self-designed 3D-printed visualization function cassette, and the CP-LAMP method achieved specific identification and visual detection of ASFV. Moreover, coupling the dual function cassette and smartphone quantitation makes the CP-LAMP assay first user-friendly, cost-effective, portable, rapid, and accurate point-of-care testing (POCT) platform for ASFV.
Collapse
Affiliation(s)
- Songqi Wang
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province; The Research Center for African Swine Fever Prevention and Control; College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Haiyan Shen
- Maoming Branch Center of Guangdong Laboratory for LingNan Modern Agricultural Science and Technology; Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Foshan, China
| | - Qijie Lin
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province; The Research Center for African Swine Fever Prevention and Control; College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Jun Huang
- College of Life Science and Engineering, Foshan University, Guangzhou, China
| | - Chunhong Zhang
- Maoming Branch Center of Guangdong Laboratory for LingNan Modern Agricultural Science and Technology; Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Foshan, China
| | - Zhicheng Liu
- Maoming Branch Center of Guangdong Laboratory for LingNan Modern Agricultural Science and Technology; Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Foshan, China
| | - Minhua Sun
- Maoming Branch Center of Guangdong Laboratory for LingNan Modern Agricultural Science and Technology; Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Foshan, China
| | - Jianfeng Zhang
- Maoming Branch Center of Guangdong Laboratory for LingNan Modern Agricultural Science and Technology; Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Foshan, China
| | - Ming Liao
- Maoming Branch Center of Guangdong Laboratory for LingNan Modern Agricultural Science and Technology; Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Foshan, China
| | - Yugu Li
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province; The Research Center for African Swine Fever Prevention and Control; College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Jianmin Zhang
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province; The Research Center for African Swine Fever Prevention and Control; College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| |
Collapse
|
5
|
Jiang D, Ma T, Hao M, Ding F, Sun K, Wang Q, Kang T, Wang D, Zhao S, Li M, Xie X, Fan P, Meng Z, Zhang S, Qian Y, Edwards J, Chen S, Li Y. Quantifying risk factors and potential geographic extent of African swine fever across the world. PLoS One 2022; 17:e0267128. [PMID: 35446903 PMCID: PMC9022809 DOI: 10.1371/journal.pone.0267128] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 04/02/2022] [Indexed: 11/26/2022] Open
Abstract
African swine fever (ASF) has spread to many countries in Africa, Europe and Asia in the past decades. However, the potential geographic extent of ASF infection is unknown. Here we combined a modeling framework with the assembled contemporary records of ASF cases and multiple covariates to predict the risk distribution of ASF at a global scale. Local spatial variations in ASF risk derived from domestic pigs is influenced strongly by livestock factors, while the risk of having ASF in wild boars is mainly associated with natural habitat covariates. The risk maps show that ASF is to be ubiquitous in many areas, with a higher risk in areas in the northern hemisphere. Nearly half of the world’s domestic pigs (1.388 billion) are in the high-risk zones. Our results provide a better understanding of the potential distribution beyond the current geographical scope of the disease.
Collapse
Affiliation(s)
- Dong Jiang
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Tian Ma
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Mengmeng Hao
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Fangyu Ding
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Kai Sun
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Qian Wang
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Tingting Kang
- School of Urban Planning and Design, Peking University Shenzhen Graduate School, Shenzhen, Guangdong, China
| | - Di Wang
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Shen Zhao
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Meng Li
- School of Geographic Sciences, Nantong University, Nantong, China
| | - Xiaolan Xie
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Peiwei Fan
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Ze Meng
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Shize Zhang
- Computer Network Information Center, Chinese Academy of Sciences, Beijing, China
| | - Yushu Qian
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - John Edwards
- School of Veterinary Medicine, Centre for Biosecurity and One Health, Murdoch University, Perth, Australia
| | - Shuai Chen
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Yin Li
- School of Veterinary Medicine, Centre for Biosecurity and One Health, Murdoch University, Perth, Australia.,Commonwealth Scientific and Industrial Research Organisation, Brisbane, Australia
| |
Collapse
|
6
|
Nguyen HN, Nguyen QT, Nguyen BTP, Tran THA, Do DT, Hoang HT. Detection of African swine fever virus in neonatal piglets with congenital tremors. Arch Virol 2022; 167:1131-1135. [PMID: 35174413 DOI: 10.1007/s00705-022-05378-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 12/20/2021] [Indexed: 11/28/2022]
Abstract
African swine fever virus (ASF) has circulated in Vietnam since 2018, causing significant losses to the pig industry. Quick, accurate diagnosis of African swine fever virus (ASFV) infection is crucial for controlling the disease. The detection of the virus in piglets with congenital tremors is described in this paper. ASFV was detected in brain tissues by polymerase chain reaction (PCR) and immunohistochemistry. Classical swine fever virus, porcine parvovirus, porcine reproductive and respiratory syndrome virus, and pseudorabies virus were not detected by PCR, suggesting that the ASFV was the cause of these neurological signs.
Collapse
Affiliation(s)
- Hai Ngoc Nguyen
- Department of Infectious Disease and Veterinary Public Health, Faculty of Animal Science and Veterinary Medicine, Nonglam University, Thu Duc district, Hochiminh City, Vietnam. .,HanViet Veterinary Diagnostic Lab, Faculty of Animal Science and Veterinary Medicine, Nonglam University, Thu Duc district, Hochiminh City, Vietnam.
| | - Quan T Nguyen
- HanViet Veterinary Diagnostic Lab, Faculty of Animal Science and Veterinary Medicine, Nonglam University, Thu Duc district, Hochiminh City, Vietnam
| | - Binh T P Nguyen
- HanViet Veterinary Diagnostic Lab, Faculty of Animal Science and Veterinary Medicine, Nonglam University, Thu Duc district, Hochiminh City, Vietnam
| | - Thu H A Tran
- HanViet Veterinary Diagnostic Lab, Faculty of Animal Science and Veterinary Medicine, Nonglam University, Thu Duc district, Hochiminh City, Vietnam
| | - Duy T Do
- Department of Infectious Disease and Veterinary Public Health, Faculty of Animal Science and Veterinary Medicine, Nonglam University, Thu Duc district, Hochiminh City, Vietnam
| | - Hai Thanh Hoang
- Department of Infectious Disease and Veterinary Public Health, Faculty of Animal Science and Veterinary Medicine, Nonglam University, Thu Duc district, Hochiminh City, Vietnam.
| |
Collapse
|
7
|
Machado G, Farthing TS, Andraud M, Lopes FPN, Lanzas C. Modelling the role of mortality-based response triggers on the effectiveness of African swine fever control strategies. Transbound Emerg Dis 2021; 69:e532-e546. [PMID: 34590433 DOI: 10.1111/tbed.14334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 01/26/2023]
Abstract
African swine fever (ASF) is considered the most impactful transboundary swine disease. In the absence of effective vaccines, control strategies are heavily dependent on mass depopulation and shipment restrictions. Here, we developed a nested multiscale model for the transmission of ASF, combining a spatially explicit network model of animal shipments with a deterministic compartmental model for the dynamics of two ASF strains within 3 km × 3 km pixels in one Brazilian state. The model outcomes are epidemic duration, number of secondary infected farms and pigs, and distance of ASF spread. The model also shows the spatial distribution of ASF epidemics. We analyzed quarantine-based control interventions in the context of mortality trigger thresholds for the deployment of control strategies. The mean epidemic duration of a moderately virulent strain was 11.2 days, assuming the first infection is detected (best-case scenario), and 15.9 days when detection is triggered at 10% mortality. For a highly virulent strain, the epidemic duration was 6.5 days and 13.1 days, respectively. The distance from the source to infected locations and the spatial distribution was not dependent on strain virulence. Under the best-case scenario, we projected an average number of infected farms of 23.77 farms and 18.8 farms for the moderate and highly virulent strains, respectively. At 10% mortality-trigger, the predicted number of infected farms was on average 46.27 farms and 42.96 farms, respectively. We also demonstrated that the establishment of ring quarantine zones regardless of size (i.e. 5 km, 15 km) was outperformed by backward animal movement tracking. The proposed modelling framework provides an evaluation of ASF epidemic potential, providing a ranking of quarantine-based control strategies that could assist animal health authorities in planning the national preparedness and response plan.
Collapse
Affiliation(s)
- Gustavo Machado
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Trevor S Farthing
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Mathieu Andraud
- Anses, French Agency for Food, Environmental and Occupational Health & Safety, Ploufragan-Plouzané-Niort Laboratory, Epidemiology, Health and Welfare Research Unit, Ploufragan, France
| | - Francisco Paulo Nunes Lopes
- Departamento de Defesa Agropecuária, Secretaria da Agricultura, Pecuária e Desenvolvimento Rural, Porto Alegre, Brazil
| | - Cristina Lanzas
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| |
Collapse
|
8
|
Kim YJ, Park B, Kang HE. Control measures to African swine fever outbreak: active response in South Korea, preparation for the future, and cooperation. J Vet Sci 2021; 22:e13. [PMID: 33522165 PMCID: PMC7850787 DOI: 10.4142/jvs.2021.22.e13] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 12/08/2020] [Accepted: 12/13/2020] [Indexed: 11/25/2022] Open
Abstract
African swine fever (ASF) is one of the most complex infectious swine diseases and the greatest concern to the pig industry owing to its high mortality and no effective vaccines available to prevent the disease. Since the first outbreak of ASF in pig farms, ASF has been identified in 14 pig farms in four cities/counties in South Korea. The outbreak was resolved in a short period because of the immediate control measures and cooperative efforts. This paper reviews the ASF outbreak and the experience of successfully stopping ASF in pig farms in South Korea through active responses to prevent the spread of ASF. In addition, suitable changes to build a sustainable pig production system and collaborative efforts to overcome the dangerous animal disease, such as ASF, are discussed.
Collapse
Affiliation(s)
- Yong Joo Kim
- Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon 39660, Korea
| | - Bongkyun Park
- Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon 39660, Korea.,Department of Veterinary Medicine Virology Lab, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea
| | - Hae Eun Kang
- Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon 39660, Korea.
| |
Collapse
|
9
|
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.
Collapse
|
10
|
Yoon H, Hong SK, Lee I, Choi DS, Lee JH, Lee E, Wee SH. Arthropods as potential vectors of African swine fever virus outbreaks in pig farms in the Republic of Korea. Vet Med Sci 2021; 7:1841-1844. [PMID: 34085400 PMCID: PMC8464277 DOI: 10.1002/vms3.545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/30/2021] [Accepted: 05/03/2021] [Indexed: 11/25/2022] Open
Abstract
The seasonality of African swine fever (ASF) in the summers and outbreaks in farms with high biosecurity levels suggest that the ASF virus (ASFV) may be transmitted by arthropod vectors. Arthropods were collected in this study from 14 pig farms with ASF outbreaks in Korea in 2019 to explore the role of arthropods as potential ASFV vectors. A total of 28,729 arthropods, including 28,508 (99.2%) Diptera, were collected using blacklight traps, insect nets and yellow sticky strips. All arthropod samples were negative for ASFV genomic DNA according to laboratory tests using real‐time polymerase chain reaction. This result may reflect the effects of immediate control measures following the detection of farms with ASF outbreaks in the early phase of infection in Korea. We collected 28,729 arthropods in 14 outbreaks pig farms in Korea to know the possibility that ASF may be transmitted by arthropod vector.
Collapse
Affiliation(s)
- Hachung Yoon
- Veterinary Epidemiology Division, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
| | - Seong-Keun Hong
- Veterinary Epidemiology Division, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
| | - Ilseob Lee
- Veterinary Epidemiology Division, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
| | - Deuk-Soo Choi
- Plant Quarantine Technology Center, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
| | - Jong-Ho Lee
- Plant Pest Control Division, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
| | - Eunesub Lee
- Veterinary Epidemiology Division, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
| | - Sung-Hwan Wee
- Department of Animal Disease Control and Quarantine, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
| |
Collapse
|
11
|
Lim JS, Vergne T, Pak SI, Kim E. Modelling the Spatial Distribution of ASF-Positive Wild Boar Carcasses in South Korea Using 2019-2020 National Surveillance Data. Animals (Basel) 2021; 11:ani11051208. [PMID: 33922261 PMCID: PMC8145688 DOI: 10.3390/ani11051208] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/19/2021] [Accepted: 04/19/2021] [Indexed: 11/18/2022] Open
Abstract
Simple Summary Since African swine fever (ASF) virus in wild boar populations can spill over to domestic pigs, it is crucial to understand the disease determinants in the wild compartment. However, the imperfect detection sensitivity of wild boar surveillance jeopardizes our ability to understand ASF spatial distribution. In this study, we used national surveillance data of ASF in wild boars collected in the Republic of Korea from 2019–2020 to model the spatial distribution of ASF-positive carcasses for two successive study periods associated with different surveillance intensity. The model allowed us to identify disease risk factors in the Republic of Korea, determine the spatial distribution of the risk of ASF, and estimate the sensitivity of surveillance. The outputs of this study are relevant to policy makers for developing and improving risk-based surveillance programs for ASF in wild boars. Abstract In September 2019, African swine fever (ASF) was reported in South Korea for the first time. Since then, more than 651 ASF cases in wild boars and 14 farm outbreaks have been notified in the country. Despite the efforts to eradicate ASF among wild boar populations, the number of reported ASF-positive wild boar carcasses have increased recently. The purpose of this study was to characterize the spatial distribution of ASF-positive wild boar carcasses to identify the risk factors associated with the presence and number of ASF-positive wild boar carcasses in the affected areas. Because surveillance efforts have substantially increased in early 2020, we divided the study into two periods (2 October 2019 to 19 January 2020, and 19 January to 28 April 2020) based on the number of reported cases and aggregated the number of reported ASF-positive carcasses into a regular grid of hexagons of 3-km diameter. To account for imperfect detection of positive carcasses, we adjusted spatial zero-inflated Poisson regression models to the number of ASF-positive wild boar carcasses per hexagon. During the first study period, proximity to North Korea was identified as the major risk factor for the presence of African swine fever virus. In addition, there were more positive carcasses reported in affected hexagons with high habitat suitability for wild boars, low heat load index (HLI), and high human density. During the second study period, proximity to an ASF-positive carcass reported during the first period was the only significant risk factor for the presence of ASF-positive carcasses. Additionally, low HLI and elevation were associated with an increased number of ASF-positive carcasses reported in the affected hexagons. Although the proportion of ASF-affected hexagons increased from 0.06 (95% credible interval (CrI): 0.05–0.07) to 0.09 (95% CrI: 0.08–0.10), the probability of reporting at least one positive carcass in ASF-affected hexagons increased from 0.49 (95% CrI: 0.41–0.57) to 0.73 (95% CrI: 0.66–0.81) between the two study periods. These results can be used to further advance risk-based surveillance strategies in the Republic of Korea.
Collapse
Affiliation(s)
- Jun-Sik Lim
- College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Korea; (J.-S.L.); (S.-I.P.)
| | - Timothée Vergne
- UMR ENVT-INRAE 1225, Ecole Nationale Vétérinaire de Toulouse, 31300 Toulouse, France;
| | - Son-Il Pak
- College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Korea; (J.-S.L.); (S.-I.P.)
| | - Eutteum Kim
- College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Korea; (J.-S.L.); (S.-I.P.)
- Correspondence:
| |
Collapse
|
12
|
Cho KH, Kim HJ, Kim DY, Yoo D, Nah JJ, Kim YJ, Kang HE. Surveillance of ASF-infected pig farms from September to October 2019 in South Korea. J Vet Sci 2021; 22:e26. [PMID: 33774941 PMCID: PMC8007448 DOI: 10.4142/jvs.2021.22.e26] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 11/22/2022] Open
Abstract
Fourteen African swine fever (ASF) outbreaks occurred in the pig farms in the northwestern region of South Korea, near the border with North Korea, from September 16, 2019 to October 9, 2019. Active and passive surveillance on the ASF-infected farms indicated that the infection was limited only to pigsties where the infected pigs were detected on the farm for the first time before further transmission to other pigsties and farms. This early detection could be one of the pivotal factors for the prompt eradication of ASF in domestic pig farms within 1 month in the northwestern region of South Korea.
Collapse
Affiliation(s)
- Ki Hyun Cho
- Animal and Plant Quarantine Agency, Gimcheon 39660, Korea
| | - Hyun Joo Kim
- Animal and Plant Quarantine Agency, Gimcheon 39660, Korea
| | - Da Young Kim
- Animal and Plant Quarantine Agency, Gimcheon 39660, Korea
| | - Daesung Yoo
- Department of Public Health, Graduate School, Korea University, Seoul 02841, Korea
| | - Jin Ju Nah
- Animal and Plant Quarantine Agency, Gimcheon 39660, Korea
| | - Yong Joo Kim
- Animal and Plant Quarantine Agency, Gimcheon 39660, Korea
| | - Hae Eun Kang
- Animal and Plant Quarantine Agency, Gimcheon 39660, Korea.
| |
Collapse
|
13
|
Jia R, Zhang G, Liu H, Chen Y, Zhou J, Liu Y, Ding P, Wang Y, Zang W, Wang A. Novel Application of Nanofluidic Chip Digital PCR for Detection of African Swine Fever Virus. Front Vet Sci 2021; 7:621840. [PMID: 33614757 PMCID: PMC7894257 DOI: 10.3389/fvets.2020.621840] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 12/11/2020] [Indexed: 01/06/2023] Open
Abstract
African swine fever virus (ASFV) gives rise to a grievous transboundary and infectious disease, African swine fever (ASF), which has caused a great economic loss in the swine industry. To prevent and control ASF, once suspicious symptoms have presented, the movement of animal and pork products should be stopped, and then, laboratory testing should be adopted to diagnose ASF. A method for ASFV DNA quantification is presented in this research, which utilizes the next-generation PCR platform, nanofluidic chip digital PCR (cdPCR). The cdPCR detection showed good linearity and repeatability. The limit of detection for cdPCR is 30.1995 copies per reaction, whereas no non-specific amplification curve was found with other swine viruses. In the detection of 69 clinical samples, the cdPCR showed significant consistency [91.30% (63/69)] to the Office International des Epizooties-approved quantitative PCR. Compared with the commercial quantitative PCR kit, the sensitivity of the cdPCR assay was 86.27% (44/50), and the specificity was 94.44% (17/18). The positive coincidence rate of the cdPCR assay was 88% (44/50). The total coincidence rate of the cdPCR and kit was 89.86% (62/69), and the kappa value reached 0.800 (P < 0.0001). This is the first time that cdPCR has been applied to detecting ASFV successfully.
Collapse
Affiliation(s)
- Rui Jia
- School of Life Sciences, Zhengzhou University, Zhengzhou, China
| | - Gaiping Zhang
- School of Life Sciences, Zhengzhou University, Zhengzhou, China
| | - Hongliang Liu
- Henan Zhongze Biological Engineering Co. LTD, Zhengzhou, China
| | - Yumei Chen
- School of Life Sciences, Zhengzhou University, Zhengzhou, China.,Henan Zhongze Biological Engineering Co. LTD, Zhengzhou, China
| | - Jingming Zhou
- School of Life Sciences, Zhengzhou University, Zhengzhou, China
| | - Yankai Liu
- Henan Zhongze Biological Engineering Co. LTD, Zhengzhou, China
| | - Peiyang Ding
- School of Life Sciences, Zhengzhou University, Zhengzhou, China
| | - Yanwei Wang
- Henan Zhongze Biological Engineering Co. LTD, Zhengzhou, China
| | - Weimin Zang
- Henan Zhongze Biological Engineering Co. LTD, Zhengzhou, China
| | - Aiping Wang
- School of Life Sciences, Zhengzhou University, Zhengzhou, China
| |
Collapse
|
14
|
Gao DM, Yu HY, Zhou W, Xia BB, Li HZ, Wang ML, Zhao J. Inhibitory effects of recombinant porcine interferon-α on porcine transmissible gastroenteritis virus infections in TGEV-seronegative piglets. Vet Microbiol 2020; 252:108930. [PMID: 33290999 DOI: 10.1016/j.vetmic.2020.108930] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 11/12/2020] [Indexed: 11/17/2022]
Abstract
Our previous research obtained purified recombinant porcine interferon-α (rPoIFN-α) containing thioredoxin (Trx) fusion tag in E. coli Rosetta (DE3). Here, we evaluate the efficacy of this rPoIFN-α to prevent piglets from the infection of the transmissible gastroenteritis virus (TGEV) attack. In this experiment, twenty-five TGEV-seronegative piglets were randomly divided into five groups. Group 1 was positive control and only challenged with TGEV; Pigs in groups 2-4 were pretreated with 2 × 10(7)IU/pig, 2 × 10(6)IU/pig, and 2 × 10(5)IU/pig rPoIFN-α before TGEV challenge. The fifth group is a negative control group. The animals of this group are pretreated only with Trx protein-containing PBS solution without TGEV challenge. After 48 h of rPoIFN-α pretreatment, the pigs in groups 1-4 were challenged by TGEV, and the pigs in group 5 were administered with PBS. The surveillance results show that Pigs pre-treated with 2 × 10 (7) IU/pig rPoIFN-α are fully aligned with the violent TGEV attack. Pigs pretreated with 2 × 10 (6) IU/pig rPoIFN-α are partially aligned with the violent TGEV attack. Though piglets pretreated with 2 × 10(6) IU/pig or 2 × 10(5)IU/pig rPoIFN-α cannot be adapted to the challenge of TGEV. However, the use of this dose of rPoIFN-α could put off the clinical signs of pigs than the positive control group of the above. These results indicate that rPoIFN-α can protect pigs from the infection of potential TGEV or delay the appearance of clinical symptoms, and its effect is dose-dependent.
Collapse
Affiliation(s)
- Dong-Mei Gao
- Department of Microbiology, Anhui Medical University, Hefei, Anhui Province, 230032, PR China; Department of Clinical Laboratory, Third Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province, 230032, PR China
| | - Hai-Yang Yu
- Department of Microbiology, Anhui Medical University, Hefei, Anhui Province, 230032, PR China
| | - Wei Zhou
- Anhui Jiuchuan Biotechnology Co., Ltd., Wuhu, Anhui, PR China
| | - Bing-Bing Xia
- Anhui Jiuchuan Biotechnology Co., Ltd., Wuhu, Anhui, PR China
| | - Hong-Zhang Li
- Department of Gastroenterology, Sanmen People's Hospital, Zhejiang, PR China.
| | - Ming-Li Wang
- Department of Microbiology, Anhui Medical University, Hefei, Anhui Province, 230032, PR China; Anhui Jiuchuan Biotechnology Co., Ltd., Wuhu, Anhui, PR China.
| | - Jun Zhao
- Department of Microbiology, Anhui Medical University, Hefei, Anhui Province, 230032, PR China; Anhui Jiuchuan Biotechnology Co., Ltd., Wuhu, Anhui, PR China; Wuhu Overseas Students Pioneer Park, Wuhu, Anhui, PR China.
| |
Collapse
|