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1.
Prev Vet Med ; 226: 106196, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569365

RESUMO

African swine fewer (ASF) is a serious disease present in Africa, Eurasia, and the Caribbean but not in continental North America. CanSpotASF describes the ASF surveillance in Canada as a phased in approach. The first enhancement to the passive surveillance was the risk-based early detection testing (rule-out testing) where eligible cases were tested for ASF virus (ASFv). The objective was to describe how the eligibility criteria were applied to cases in western Canada. In particular, to assess if cases tested for ASFv had eligible conditions and if pathology cases with eligible conditions were tested for ASFv based on the data collated by Canada West Swine Health Intelligence Network (CWSHIN) from British Columbia, Alberta, Saskatchewan, and Manitoba. The study period was August 2020 to December 2022 and the data included two study laboratories. We found that over 90% of cases tested for ASFv had eligible conditions as defined in CanSpotASF. The eligibility criteria were applied at three stages of the disease investigation process: 1) the clinical presentation in the herd; 2) at the initial laboratory assessment; and 3) the final pathology diagnosis. At the two study laboratories the proportion of all submitted cases (culture, serology, PCR, pathology) tested for ASFv was very low 1%. However, in the pathology cases specifically targeted in CanSpotASF, and the proportion of tested cases was 12%. In addition, for eligible pathology cases (eligible diagnosis or test) the proportion tested was higher 15%. These results indicated that CanSpotASF targeted herds with submissions for pathological examination and to some degree eligible conditions which would be herds with health issues (known or unknown). We interpret this as a first step towards risk-based surveillance with health as the defining factor.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Suínos , Animais , Febre Suína Africana/diagnóstico , Febre Suína Africana/epidemiologia , África , Alberta
2.
Viruses ; 16(3)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38543702

RESUMO

In the event of an outbreak of African swine fever (ASF) in pig farms, the European Union (EU) legislation requires the establishment of a restricted zone, consisting of a protection zone with a radius of at least 3 km and a surveillance zone with a radius of at least 10 km around the outbreak. The main purpose of the restricted zone is to stop the spread of the disease by detecting further outbreaks. We evaluated the effectiveness and necessity of the restricted zone in the Baltic States by looking at how many secondary outbreaks were detected inside and outside the protection and surveillance zones and by what means. Secondary outbreaks are outbreaks with an epidemiological link to a primary outbreak while a primary outbreak is an outbreak that is not epidemiologically linked to any previous outbreak. From 2014 to 2023, a total of 272 outbreaks in domestic pigs were confirmed, where 263 (96.7%) were primary outbreaks and 9 (3.3%) were secondary outbreaks. Eight of the secondary outbreaks were detected by epidemiological enquiry and one by passive surveillance. Epidemiological enquiries are legally required investigations on an outbreak farm to find out when and how the virus entered the farm and to obtain information on contact farms where the ASF virus may have been spread. Of the eight secondary outbreaks detected by epidemiological investigations, six were within the protection zone, one was within the surveillance zone and one outside the restricted zone. Epidemiological investigations were therefore the most effective means of detecting secondary outbreaks, whether inside or outside the restricted zones, while active surveillance was not effective. Active surveillance are legally prescribed activities carried out by the competent authorities in the restricted zones. Furthermore, as ASF is no longer a rare and exotic disease in the EU, it could be listed as a "Category B" disease, which in turn would allow for more flexibility and "tailor-made" control measures, e.g., regarding the size of the restricted zone.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Sus scrofa , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Países Bálticos
3.
Prev Vet Med ; 226: 106168, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38507888

RESUMO

Several propagation routes drive animal disease dissemination, and among these routes, contaminated vehicles traveling between farms have been associated with indirect disease transmission. In this study, we used near-real-time vehicle movement data and vehicle cleaning efficacy to reconstruct the between-farm dissemination of the African swine fever virus (ASFV). We collected one year of Global Positioning System data of 823 vehicles transporting feed, pigs, and people to 6363 swine production farms in two regions in the U.S. Without cleaning, vehicles connected up to 2157 farms in region one and 437 farms in region two. Individually, in region one vehicles transporting feed connected 2151 farms, pigs to farms 2089 farms, pigs to market 1507 farms, undefined vehicles 1760 farm, and personnel three farms. The simulation results indicated that the contact networks were reduced the most for crew transport vehicles with a 66% reduction, followed by vehicles carrying pigs to market and farms, with reductions of 43% and 26%, respectively, when 100% cleaning efficacy was achieved. The results of this study showed that even when vehicle cleaning and disinfection are 100% effective, vehicles are still connected to numerous farms. This emphasizes the importance of better understanding transmission risks posed by vehicles to the swine industry and regulatory agencies.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Humanos , Suínos , Animais , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/prevenção & controle , Fazendas , Incerteza , Simulação por Computador , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Surtos de Doenças/veterinária
4.
PLoS One ; 19(3): e0293049, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512923

RESUMO

African swine fever (ASF) is a devastating disease of domestic pigs that has spread across the globe since its introduction into Georgia in 2007. The etiological agent is a large double-stranded DNA virus with a genome of 170 to 180 kb in length depending on the isolate. Much of the differences in genome length between isolates are due to variations in the copy number of five different multigene families that are encoded in repetitive regions that are towards the termini of the covalently closed ends of the genome. Molecular epidemiology of African swine fever virus (ASFV) is primarily based on Sanger sequencing of a few conserved and variable regions, but due to the stability of the dsDNA genome changes in the variable regions occur relatively slowly. Observations in Europe and Asia have shown that changes in other genetic loci can occur and that this could be useful in molecular tracking. ASFV has been circulating in Western Africa for at least forty years. It is therefore reasonable to assume that changes may have accumulated in regions of the genome other than the standard targets over the years. At present only one full genome sequence is available for an isolate from Western Africa, that of a highly virulent isolate collected from Benin during an outbreak in 1997. In Cameroon, ASFV was first reported in 1981 and outbreaks have been reported to the present day and is considered endemic. Here we report three full genome sequences from Cameroon isolates of 1982, 1994 and 2018 outbreaks and identify novel single nucleotide polymorphisms and insertion-deletions that may prove useful for molecular epidemiology studies in Western Africa and beyond.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Febre Suína Africana/epidemiologia , Camarões/epidemiologia , Sus scrofa/genética , Análise de Sequência , Análise de Sequência de DNA
5.
Sci Rep ; 14(1): 3414, 2024 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341478

RESUMO

African swine fever (ASF) is an infectious and highly fatal disease affecting wild and domestic swine, which is unstoppably spreading worldwide. In Europe, wild boars are one of the main drivers of spread, transmission, and maintenance of the disease. Landscape connectivity studies are the main discipline to analyze wild-species dispersal networks, and it can be an essential tool to predict dispersal-wild boar movement routes and probabilities and therefore the associated potential ASF spread through the suitable habitat. We aimed to integrate wild boar habitat connectivity predictions with their occurrence, population abundance, and ASF notifications to calculate the impact (i.e., the capacity of a landscape feature to favor ASF spread) and the risk (i.e., the likelihood of a habitat patch becoming infected) of wild boar infection across Europe. Furthermore, we tested the accuracy of the risk of infection by comparing the results with the temporal distribution of ASF cases. Our findings identified the areas with the highest impact and risk factors within Europe's central and Eastern regions where ASF is currently distributed. Additionally, the impact factor was 31 times higher on habitat patches that were infected vs non-infected, proving the utility of the proposed approach and the key role of wild boar movements in ASF-spread. All data and resulting maps are openly accessible and usable.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Febre Suína Africana/epidemiologia , Sus scrofa , Europa (Continente)/epidemiologia , Fatores de Risco
6.
Braz J Microbiol ; 55(1): 997-1010, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311710

RESUMO

The swine industry across the globe is recently facing a devastating situation imparted by a highly contagious and deadly viral disease, African swine fever. The disease is caused by a DNA virus, the African swine fever virus (ASFV) of the genus Asfivirus. ASFV affects both wild boars and domestic pigs resulting in an acute form of hemorrhagic fever. Since the first report in 1921, the disease remains endemic in some of the African countries. However, the recent occurrence of ASF outbreaks in Asia led to a fresh and formidable challenge to the global swine production industry. Culling of the infected animals along with the implementation of strict sanitary measures remains the only options to control this devastating disease. Efforts to develop an effective and safe vaccine against ASF began as early as in the mid-1960s. Different approaches have been employed for the development of effective ASF vaccines including inactivated vaccines, subunit vaccines, DNA vaccines, virus-vectored vaccines, and live attenuated vaccines (LAVs). Inactivated vaccines are a non-feasible strategy against ASF due to their inability to generate a complete cellular immune response. However genetically engineered vaccines, such as subunit vaccines, DNA vaccines, and virus vector vaccines, represent tailored approaches with minimal adverse effects and enhanced safety profiles. As per the available data, gene deleted LAVs appear to be the most potential vaccine candidates. Currently, a gene deleted LAV (ASFV-G-∆I177L), developed in Vietnam, stands as the sole commercially available vaccine against ASF. The major barrier to the goal of developing an effective vaccine is the critical gaps in the knowledge of ASFV biology and the immune response induced by ASFV infection. The precise contribution of various hosts, vectors, and environmental factors in the virus transmission must also be investigated in depth to unravel the disease epidemiology. In this review, we mainly focus on the recent progress in vaccine development against ASF and the major gaps associated with it.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vacinas de DNA , Vacinas Virais , Suínos , Animais , Febre Suína Africana/prevenção & controle , Febre Suína Africana/epidemiologia , Vírus da Febre Suína Africana/genética , Vacinas de DNA/genética , Sus scrofa , Vacinas Virais/genética , Vacinas Atenuadas/genética , Desenvolvimento de Vacinas , Vacinas de Produtos Inativados , Vacinas de Subunidades
7.
Epidemiol Infect ; 152: e27, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38282573

RESUMO

Introduction of African swine fever (ASF) to China in mid-2018 and the subsequent transboundary spread across Asia devastated regional swine production, affecting live pig and pork product-related markets worldwide. To explore the spatiotemporal spread of ASF in China, we reconstructed possible ASF transmission networks using nearest neighbour, exponential function, equal probability, and spatiotemporal case-distribution algorithms. From these networks, we estimated the reproduction numbers, serial intervals, and transmission distances of the outbreak. The mean serial interval between paired units was around 29 days for all algorithms, while the mean transmission distance ranged 332 -456 km. The reproduction numbers for each algorithm peaked during the first two weeks and steadily declined through the end of 2018 before hovering around the epidemic threshold value of 1 with sporadic increases during 2019. These results suggest that 1) swine husbandry practices and production systems that lend themselves to long-range transmission drove ASF spread; 2) outbreaks went undetected by the surveillance system. Efforts by China and other affected countries to control ASF within their jurisdictions may be aided by the reconstructed spatiotemporal model. Continued support for strict implementation of biosecurity standards and improvements to ASF surveillance is essential for halting transmission in China and spread across Asia.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Epidemias , Doenças dos Suínos , Suínos , Humanos , Animais , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Surtos de Doenças/veterinária , China/epidemiologia , Sus scrofa , Doenças dos Suínos/epidemiologia
8.
Sci Rep ; 14(1): 382, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172492

RESUMO

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.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Animais , Febre Suína Africana/epidemiologia , Letônia/epidemiologia , Análise Espacial , Sus scrofa , Suínos
10.
Viruses ; 16(1)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38257836

RESUMO

African swine fever (ASF) is one of the most important and serious contagious hemorrhagic viral diseases affecting domestic pigs and wild boar and is associated with high mortality rates while also having an extensive sanitary and socioeconomic impact on the international trade of animal and swine products. The early detection of the disease is often hampered by inadequate surveillance. Among the surveillance strategies used, passive surveillance of wild boars is considered the most effective method for controlling the African swine fever virus (ASFV). Otherwise, the design of a sufficiently sensitive ASF surveillance system requires a solid understanding of the epidemiology related to the local eco-social context, especially in the absence of virus detection. Even if the number of carcasses needed to demonstrate ASF eradication has been established, the scientific context lacks detail compared to protocols applied in the active search for wild boar carcasses. The aim of this study was to describe the protocol applied in the active search for carcasses, providing detailed information on the number of people and dogs as well as the amount of time and space used within the Mediterranean area. Using a specific tool developed to record, trace, and share field data (the GAIA observer app), a total of 33 active searches for wild boar carcasses were organized during 2021-2023. Most of these searches were planned to find carcasses that had previously been reported by hunters. A total of 24 carcasses were found, with only 2 carcasses not previously reported. The final protocol applied involved four people, with an average speed of 1.5 km/h. When a carcass had been previously reported, about 2 km of distance had to be covered in about 1.5 h to find the carcass, and even less time was spent when a dog (untrained) was present. In conclusion, it can be stated that, when searching for carcasses, solid collaboration with local hunters or other forest visitors is necessary to ensure carcasses are reported. The process involves small groups of experts actively searching for carcasses, possibly with the use of hunting dogs without special training. The data presented could be of valid support for those countries characterized by Mediterranean vegetation that are faced with the need to plan active carcass searches.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Humanos , Animais , Cães , Suínos , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Comércio , Internacionalidade , Itália/epidemiologia , Ilhas do Mediterrâneo , Sus scrofa
11.
Trop Anim Health Prod ; 56(1): 39, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38206527

RESUMO

African swine fever (ASF) is a highly contagious, notifiable, and fatal hemorrhagic viral disease affecting domestic and wild pigs. The disease was reported for the first time in India during 2020, resulted in serious outbreaks and economic loss in North-Eastern (NE) parts, since 47% of the Indian pig population is distributed in the NE region. The present study focused on analyzing the spatial autocorrelation, spatio-temporal patterns, and directional trend of the disease in NE India during 2020-2021. The ASF outbreak data (2020-2021) were collected from the offices of the Department of Animal Husbandry and Veterinary Services in seven NE states of India to identify the potential clusters, spatio-temporal aggregation, temporal distribution, disease spread, density maps, and risk zones. Between 2020 and 2021, a total of 321 ASF outbreaks were recorded, resulting in 59,377 deaths. The spatial pattern analysis of the outbreak data (2020-2021) revealed that ASF outbreaks were clustered in 2020 (z score = 2.20, p < .01) and 2021 (z score = 4.89, p < .01). Spatial autocorrelation and Moran's I value (0.05-0.06 in 2020 and 2021) revealed the spatial clustering and spatial relationship between the outbreaks. The hotspot analysis identified districts of Arunachal Pradesh, Assam and districts of Mizoram, Tripura as significant hotspots in 2020 and 2021, respectively. The spatial-scan statistics with a purely spatial and purely temporal analysis revealed six and one significant clusters, respectively. Retrospective unadjusted, temporal, and spatially adjusted space-time analysis detected five, five, and two statistically significant (p < .01) clusters, respectively. The directional trend analysis identified the direction of disease distribution as northeast-southwest (2020) and north-south (2021), indicate the possibility of ASF introduction to India from China. The high-risk zones and spatio-temporal pattern of ASF outbreaks identified in the present study can be used as a guide for deploying proper prevention, optimizing resource allocation and disease control measures in NE Indian states.


Assuntos
Febre Suína Africana , Doenças dos Suínos , Animais , Suínos , Febre Suína Africana/epidemiologia , Estudos Retrospectivos , Surtos de Doenças/veterinária , Criação de Animais Domésticos , Índia/epidemiologia
12.
Viruses ; 16(1)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275963

RESUMO

African swine fever (ASF) is one of the most severe suid diseases, impacting the pig industry and wild suid populations. Once an ASF vaccine is available, identifying a sufficient density of vaccination fields will be crucial to achieve eradication success. In 2020-2023, we live-trapped and monitored 27 wild boars in different areas of Lithuania, in which the wild boars were fed at artificial stations. We built a simulation study to estimate the probability of a successful ASF vaccination as a function of different eco-epidemiological factors. The average 32-day home range size across all individuals was 16.2 km2 (SD = 16.9). The wild boars made frequent visits of short durations to the feeding sites rather than long visits interposed by long periods of absence. A feeding site density of 0.5/km2 corresponded to an expected vaccination rate of only 20%. The vaccination probability increased to about 75% when the feeding site density was 1.0/km2. Our results suggest that at least one vaccination field/km2 should be used when planning an ASF vaccination campaign to ensure that everyone in the population has at least 5-10 vaccination sites available inside the home range. Similar studies should be conducted in the other ecological contexts in which ASF is present today or will be present in the future, with the objective being to estimate a context-specific relationship between wild boar movement patterns and an optimal vaccination strategy.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Humanos , Suínos , Animais , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Sus scrofa , Lituânia/epidemiologia , Vacinação/veterinária
13.
Int J Biol Macromol ; 255: 128111, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37979744

RESUMO

African swine fever (ASF), caused by the African swine fever virus (ASFV), is now widespread in many countries and severely affects the commercial rearing of swine. Rapid and early diagnosis is crucial for the prevention of ASF. ASFV mature virions comprise the inner envelope protein, p22, making it an excellent candidate for the serological diagnosis and surveillance of ASF. In this study, the prokaryotic-expressed p22 recombinant protein was prepared and purified for immunization in mice. Four monoclonal antibodies (mAbs) were identified using hybridoma cell fusion, clone purification, and immunological assays. The epitopes of mAbs 14G1 and 22D8 were further defined by alanine-scanning mutagenesis. Our results showed that amino acids C39, K40, V41, D42, C45, G48, E49, and C51 directly bound to 14G1, while the key amino acid epitope for 22D8 included K161, Y162, G163, D165, H166, I167, and I168. Homologous and structural analysis revealed that these sites were highly conserved across Asian and European ASFV strains, and the amino acids identified were located on the surface of p22. Thus, our study contributes to a better understanding of the antigenicity of the ASFV p22 protein, and the results could facilitate the prevention and control of ASF.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Camundongos , Vírus da Febre Suína Africana/genética , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Mapeamento de Epitopos , Anticorpos Monoclonais , Anticorpos Antivirais , Epitopos , Aminoácidos
14.
J Am Vet Med Assoc ; 262(1): 109-116, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103389

RESUMO

Foreign animal disease (FAD) preparedness is a high priority for state and federal governments to ensure the protection of the nation's livestock industry. Highly contagious diseases such as African swine fever (ASF) have been the focus of recent advancements in FAD preparedness, including the development of disease-specific response plans. At the state level, FAD response plans provide a framework to help ensure a rapid and coordinated response that considers the resources and realities of that state; however, preparing a comprehensive plan requires collaboration across multiple agencies and sectors that can be difficult to operationalize. To initiate systematic state-level ASF response plan writing and identify gaps in preparedness, university and industry stakeholders partnered with the Ohio Department of Agriculture and USDA to develop the Ohio African Swine Fever Response Plan Workshop. A linear planning model was used to implement the workshop in May 2021. All planning and workshop activities were conducted fully virtually, prompted by public health restrictions in response to COVID-19. Sixty-four participants, representing multiple sectors and stakeholder groups including state/federal/industry animal health officials, emergency management, environmental protection, and academia, contributed to the workshop. Spanning 3 days, participants identified current response capabilities and areas requiring additional planning for an effective state-level response. The workshop generated recommendations from a multisectoral perspective for subcommittees tasked with developing standard operating procedures for the Ohio ASF Response Plan. The methodology and resources used to plan, implement, and evaluate the workshop are described to provide a model for state-level response planning.


Assuntos
Febre Suína Africana , Doenças dos Suínos , Animais , Suínos , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Ohio/epidemiologia , Saúde Pública , Gado
15.
Acta Vet Scand ; 65(1): 58, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110953

RESUMO

BACKGROUND: African swine fever (ASF), a viral hemorrhagic disease in domestic pigs and wild boar with up to 100% case fatality, was confirmed in Swedish wild boar in September 2023. The responsible authorities launched a control programme to eradicate the infection. The aim of the current study was to understand (i) how Swedish pig farmers have perceived the information issued by authorities and other stakeholders since the discovery of ASF in wild boar, (ii) which risks they see for introducing the infection to their farm, (iii) what biosecurity measures they have taken on their farms, and (iv) their outlook on the future. Such information is important for evaluating the effectiveness of the early stages of ASF control in Sweden. A questionnaire was designed and distributed to members of the Swedish pig producers' organisation. RESULTS: A total of 155 farmers responded to the survey (response rate 36%). Almost all respondents had received general information about ASF (91%, n = 138), and 72% (n = 109) had received information about how they can protect their farm from ASF introduction. A majority (87%, n = 118) thought the information was easy to understand, 90% (n = 137) that is was relevant, and 77% (n = 117) that they currently did not lack any information. If given the resources necessary, 58% (n = 84) of the farmers would like to take additional measures such as fencing, and heavily reduce or eradicate the wild boar population. Wild boars were considered the greatest risk for introduction of ASF into their herd (39%, n = 57), followed by people (30%, n = 44), and transports (16%, n = 23). Many farmers (66%, n = 88) had a positive outlook on the future, and 89% (n = 127) have not changed their plans for the future since the ASF outbreak. CONCLUSIONS: The responding farmers were in general satisfied with the information received in the beginning of the ASF outbreak. The majority have a positive outlook on the future and the outbreak has not caused them to change their plans. Actions that were highlighted as important to safeguard Sweden's pig production included measures to control the wild boar population.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Suínos , Animais , Humanos , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Fazendeiros , Suécia/epidemiologia , Biosseguridade , Fatores de Risco , Sus scrofa , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Inquéritos e Questionários , Doenças dos Suínos/epidemiologia
16.
Microb Pathog ; 185: 106452, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37972743

RESUMO

The present investigation focuses on examining the clinical, histopathological, and ultrastructural changes that occurred in pig, during an outbreak of African swine fever (ASF) in 2022 in Assam, India. The disease initially manifested as a per-acute case with high mortality but without any evident clinical signs. Subsequently, some animals exhibited an acute form of the disease characterized by high fever (104-106 °F), anorexia, vomiting, respiratory distress, and bleeding from the anal and nasal orifices. During acute African swine fever virus (ASFV) infections, elevated levels of pro-inflammatory IL-1α, IL-1ß, IL-6, TNF, CCL2, CCL5, and CXCL10 were detected in the palatine tonsil, lymph nodes, spleen, and kidney using qPCR assay. These molecular changes were associated with haemorrhages, edemas, and lymphoid depletion. Postmortem examinations revealed prominent features such as splenomegaly with haemorrhages, haemorrhagic lymphadenitis, severe petechial haemorrhage in the kidney, pneumonia in the lungs, and necrotic palatine tonsil. Histopathological analysis demonstrated lymphocyte depletion in lymphoid organs, multi-organ haemorrhages, and interstitial pneumonia in the lungs. Scanning electron microscopy (SEM) further confirmed lymphocyte depletion in lymphoid organs through lymphocyte apoptosis and kidney damage with distorted tubules due to red blood cell destruction. Transmission electron microscopy reaffirmed lymphocyte apoptosis by observing chromatin condensation and nucleus margination in lymphocytes of lymphoid organs. These findings provide comprehensive insights into the clinical, histopathological, and ultrastructural aspects of ASF outbreak in pigs. Understanding the pathological changes associated with ASF can contribute to improved diagnosis, prevention, and control measures for this highly contagious and economically devastating viral disease.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Febre Suína Africana/epidemiologia , Febre Suína Africana/patologia , Linfócitos , Surtos de Doenças , Hemorragia , Sus scrofa
17.
Viruses ; 15(11)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38005923

RESUMO

The African swine fever virus (ASFV) is currently causing a world-wide pandemic of a highly lethal disease in domestic swine and wild boar. Currently, recombinant ASF live-attenuated vaccines based on a genotype II virus strain are commercially available in Vietnam. With 25 reported ASFV genotypes in the literature, it is important to understand the molecular basis and usefulness of ASFV genotyping, as well as the true significance of genotypes in the epidemiology, transmission, evolution, control, and prevention of ASFV. Historically, genotyping of ASFV was used for the epidemiological tracking of the disease and was based on the analysis of small fragments that represent less than 1% of the viral genome. The predominant method for genotyping ASFV relies on the sequencing of a fragment within the gene encoding the structural p72 protein. Genotype assignment has been accomplished through automated phylogenetic trees or by comparing the target sequence to the most closely related genotyped p72 gene. To evaluate its appropriateness for the classification of genotypes by p72, we reanalyzed all available genomic data for ASFV. We conclude that the majority of p72-based genotypes, when initially created, were neither identified under any specific methodological criteria nor correctly compared with the already existing ASFV genotypes. Based on our analysis of the p72 protein sequences, we propose that the current twenty-five genotypes, created exclusively based on the p72 sequence, should be reduced to only six genotypes. To help differentiate between the new and old genotype classification systems, we propose that Arabic numerals (1, 2, 8, 9, 15, and 23) be used instead of the previously used Roman numerals. Furthermore, we discuss the usefulness of genotyping ASFV isolates based only on the p72 gene sequence.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Animais , Febre Suína Africana/epidemiologia , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/genética , Genótipo , Filogenia , Análise de Sequência , Sus scrofa , Suínos
18.
Viruses ; 15(11)2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38005951

RESUMO

African swine fever is a contagious disease, affecting pigs and wild boars, which poses a major threat to the pig industry worldwide and, therefore, to the agricultural economies of many countries. Despite intensive studies, an effective vaccine against the disease has not yet been developed. Since 2007, ASFV has been circulating in Eastern and Central Europe, covering an increasingly large area. As of 2018, the disease is additionally spreading at an unprecedented scale in Southeast Asia, nearly ruining China's pig-producing sector and generating economic losses of approximately USD 111.2 billion in 2019. ASFV's high resistance to environmental conditions, together with the lack of an approved vaccine, plays a key role in the spread of the disease. Therefore, the biosecurity and disinfection of pig farms are the only effective tools through which to prevent ASFV from entering the farms. The selection of a disinfectant, with research-proven efficacy and proper use, taking into account environmental conditions, exposure time, pH range, and temperature, plays a crucial role in the disinfection process. Despite the significant importance of ASF epizootics, little information is available on the effectiveness of different disinfectants against ASFV. In this review, we have compiled the current knowledge on the transmission, spread, and control of ASF using the principles of biosecurity, with particular attention to disinfection, including a perspective based on Polish experience with ASF control.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Desinfetantes , Vacinas , Suínos , Animais , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Polônia/epidemiologia , Desinfecção , Biosseguridade , Desinfetantes/farmacologia , Sus scrofa
19.
Trop Anim Health Prod ; 55(6): 410, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37987884

RESUMO

Pig production in Uganda is constrained by African swine fever (ASF) which is endemic in the country. Current measures taken by the Government of Uganda in controlling ASF outbreaks include trade and livestock movement restrictions, called "quarantine." Little is known about the actions of, and impact of value chain actors in response to ASF quarantines. This study describes actions that different stakeholders in the smallholder pig value chain took, and the perceived economic impact, during ASF quarantines. Data was collected in ten focus group discussions (FGD) using participatory epidemiology tools and two key informants' (KIs) interviews with District Veterinary Officers (DVOs) of Kisoro and Moyo districts in Uganda. The results show that during ASF quarantine, pig value chain actors shifted their activities from formal places such as livestock markets, slaughter slabs, pork butcheries and pork joints to informal places such as farmers' homesteads. Farmers were perceived the most economically affected stakeholder group with forgone income due to unsold pigs, costs for implementing biosecurity measures and extra costs for feeding unsold pigs being the major perceived causes of the losses. The continued trade in pigs and pig products in informal marketplaces suggests that quarantine might not be effective for hindering activities that might spread ASF in these settings. The perceived economic losses provide an insight into the negative economic impact of the quarantine for the different stakeholders.


Assuntos
Febre Suína Africana , Doenças dos Suínos , Suínos , Animais , Humanos , Uganda/epidemiologia , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Surtos de Doenças , Fazendeiros , Grupos Focais , Gado
20.
Sensors (Basel) ; 23(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37837032

RESUMO

Transboundary disease control, as for African swine fever (ASF), requires rapid understanding of the locally relevant potential risk factors. Here, we show how satellite remote sensing can be applied to the field of animal disease control by providing an epidemiological context for the implementation of measures against the occurrence of ASF in Germany. We find that remotely sensed observations are of the greatest value at a lower jurisdictional level, particularly in support of wild boar carcass search efforts.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Tecnologia de Sensoriamento Remoto , Sus scrofa , Alemanha
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