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1.
Trop Anim Health Prod ; 56(5): 166, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758410

RESUMO

African Swine Fever (ASF) disease transmission parameters are crucial for making response and control decisions when faced with an outbreak, yet they are poorly quantified for smallholder and village contexts within Southeast Asia. Whilst disease-specific factors - such as latent and infectious periods - should remain reasonably consistent, host, environmental and management factors are likely to affect the rate of disease spread. These differences are investigated using Approximate Bayesian Computation with Sequential Monte-Carlo methods to provide disease parameter estimates in four naïve pig populations in villages of Lao People's Democratic Republic. The villages represent smallholder pig farmers of the Northern province of Oudomxay and the Southern province of Savannakhet, and the model utilised field mortality data to validate the transmission parameter estimates over the course of multiple model generations. The basic reproductive number between-pigs was estimated to range from 3.08 to 7.80, whilst the latent and infectious periods were consistent with those published in the literature for similar genotypes in the region (4.72 to 6.19 days and 2.63 to 5.50 days, respectively). These findings demonstrate that smallholder village pigs interact similarly to commercial pigs, however the spread of disease may occur slightly slower than in commercial study groups. Furthermore, the findings demonstrated that despite diversity across the study groups, the disease behaved in a consistent manner. This data can be used in disease control programs or for future modelling of ASF in smallholder contexts.


Assuntos
Febre Suína Africana , Teorema de Bayes , Animais , Febre Suína Africana/transmissão , Febre Suína Africana/epidemiologia , Suínos , Laos/epidemiologia , Número Básico de Reprodução , Criação de Animais Domésticos/métodos , Método de Monte Carlo , Sus scrofa , Vírus da Febre Suína Africana/fisiologia , Surtos de Doenças/veterinária
2.
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
3.
Prev Vet Med ; 227: 106193, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626594

RESUMO

Animal disease outbreaks, such as the recent outbreak of African Swine Fever in 2018, are a major concern for stakeholders across the food supply chain due to their potential to disrupt global food security, cause economic losses, and threaten animal welfare. As a result of their transboundary nature, discussions have shifted to preventive measures aimed at protecting livestock while ensuring food security and safety. Emergency assistance has been a critical response option during pandemics. However, this may not be sustainable in the long run because the expectation of government bailout may encourage risk taking behaviours. Our hypothesis is that an indemnity policy that is conditioned on showing biosecurity practices would increase compliance and reduce government expenditure during disease outbreaks. We developed and launched a survey from March to July 2022 targeted at swine producers across the US. From the survey, we examined livestock farmers' attitudes and intentions regarding biosecurity investment and assessed their attitudes towards the purchase of livestock insurance and reporting suspected infected livestock on their farm. We used a partial proportion odds model analysis to examine the model. Our analysis revealed that intention to call a veterinarian, trust in government agencies and risk perception of farmers were instrumental in the willingness to self-invest in biosecurity, purchase livestock insurance, and promptly report infected livestock on their farms. This provides evidence that biosecurity compliance would increase if indemnification was tied to a demonstration of effort to adopt biosecurity practices. We also show that individuals who have been in the industry for a longer period may become complacent and less likely to report outbreaks. Farmers with a higher share of income from their production operations bear a greater risk from their operational income and are more willing to report any suspected infections on their farms. The data suggest that motivating the willingness of farmers to invest in biosecurity while overcoming cost concerns is achievable.


Assuntos
Febre Suína Africana , Surtos de Doenças , Fazendeiros , Animais , Febre Suína Africana/prevenção & controle , Febre Suína Africana/epidemiologia , Febre Suína Africana/psicologia , Estados Unidos/epidemiologia , Surtos de Doenças/veterinária , Surtos de Doenças/prevenção & controle , Suínos , Fazendeiros/psicologia , Criação de Animais Domésticos/métodos , Biosseguridade , Humanos , Conhecimentos, Atitudes e Prática em Saúde , Masculino , Feminino , Inquéritos e Questionários
4.
Viruses ; 16(4)2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38675848

RESUMO

Rapid and early detection of infectious diseases in pigs is important, especially for the implementation of control measures in suspected cases of African swine fever (ASF), as an effective and safe vaccine is not yet available in most of the affected countries. Additionally, analysis for swine influenza is of significance due to its high morbidity rate (up to 100%) despite a lower mortality rate compared to ASF. The wide distribution of swine influenza A virus (SwIAV) across various countries, the emergence of constantly new recombinant strains, and the danger of human infection underscore the need for rapid and accurate diagnosis. Several diagnostic approaches and commercial methods should be applied depending on the scenario, type of sample and the objective of the studies being implemented. At the early diagnosis of an outbreak, virus genome detection using a variety of PCR assays proves to be the most sensitive and specific technique. As the disease evolves, serology gains diagnostic value, as specific antibodies appear later in the course of the disease (after 7-10 days post-infection (DPI) for ASF and between 10-21 DPI for SwIAV). The ongoing development of commercial kits with enhanced sensitivity and specificity is evident. This review aims to analyse recent advances and current commercial kits utilised for the diagnosis of ASF and SwIAV.


Assuntos
Febre Suína Africana , Vírus da Influenza A , Infecções por Orthomyxoviridae , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Animais , Febre Suína Africana/diagnóstico , Febre Suína Africana/virologia , Febre Suína Africana/epidemiologia , Suínos , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/virologia , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/virologia , Técnicas de Diagnóstico Molecular/métodos
5.
Emerg Infect Dis ; 30(5): 991-994, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38666642

RESUMO

African swine fever virus (ASFV) genotype II is endemic to Vietnam. We detected recombinant ASFV genotypes I and II (rASFV I/II) strains in domestic pigs from 6 northern provinces in Vietnam. The introduction of rASFV I/II strains could complicate ongoing ASFV control measures in the region.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Genótipo , Filogenia , Animais , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/classificação , Vietnã/epidemiologia , Febre Suína Africana/epidemiologia , Febre Suína Africana/virologia , Suínos , Sus scrofa/virologia , Recombinação Genética
6.
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
7.
Viruses ; 16(3)2024 02 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
8.
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
9.
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
10.
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 Antigênicas
11.
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
12.
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
14.
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
15.
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
16.
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
17.
Braz J Microbiol ; 55(1): 1017-1022, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38041718

RESUMO

Porcine reproductive and respiratory syndrome (PRRS) and African swine fever (ASF) are economically important diseases of pigs throughout the world. During an outbreak, all age groups of animals except piglets < 1 month of age were affected with symptoms of high fever, cutaneous hemorrhages, vomition with blood, diarrhea, poor appetite, ataxia, and death. The outbreak was confirmed by the detection of the N gene of the porcine reproductive and respiratory syndrome virus (PRRSV) and the VP72 gene of the African swine fever virus (ASFV) by PCR in representative blood samples from affected pigs followed by Sanger sequencing. Mixed infection was also confirmed by simultaneous detection of both the viruses using multiplex PCR. Phylogenetic analysis of both the viruses revealed that the outbreak was related to ASFV and PRRSV strains from China which were also closely related to the PRRSV and ASFV strains from the recent outbreak from India. The study confirmed the involvement of genotype II of ASFV and genotype 2 of PRRSV in the present outbreak. Interestingly, PRRSV associated with the present outbreak was characterized as a highly pathogenic PRRSV. Therefore, the present study indicates the possibility of future waves or further outbreaks of these diseases (PRRS and ASF) in this region. This is the first report of ASFV and PRRSV co-infection in pigs from India.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Coinfecção , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Suínos , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Febre Suína Africana/genética , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Febre Suína Africana/epidemiologia , Coinfecção/epidemiologia , Coinfecção/veterinária , Filogenia
18.
Vet Res Commun ; 48(2): 827-837, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37955753

RESUMO

This study investigates suspected African swine fever (ASF) outbreaks in two villages of Kannur district in Kerala, India, with the aim of identifying the causative agent and its genotype, the source of infection, and estimating the economic losses due to the outbreaks. Clinically, the disease was acute with high mortality, while gross pathology was characterized by widespread haemorrhages in various organs, especially the spleen, which was dark, enlarged and had friable cut surfaces with diffuse haemorrhages. Notably, histopathological examination revealed multifocal, diffuse haemorrhages in the splenic parenchyma and lymphoid depletion accompanied by lymphoid cell necrosis. The clinico-pathological observations were suggestive of ASF, which was confirmed by PCR. The source of outbreak was identified as swill and it was a likely point source infection as revealed by epidemic curve analysis. The phylogenetic analysis of p72 gene identified the ASFV in the current outbreak as genotype-II and IGR II variant consistent with ASFVs detected in India thus far. However, the sequence analysis of the Central Variable Region (CVR) of the B602L gene showed that the ASFVs circulating in Kerala (South India) formed a separate clade along with those found in Mizoram (North East India), while ASFVs circulating in Arunachal Pradesh and Assam states of India grouped in to different clade. This study represents the first investigation of ASF outbreak in South India, establishing the genetic relatedness of the ASFV circulating in this region with that in other parts of the country. The study also underscores the utility of the CVR of the B602L gene in genetically characterizing highly similar Genotype II ASFVs to understand the spread of ASF within the country.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Suínos , Animais , Febre Suína Africana/epidemiologia , Sus scrofa , Vírus da Febre Suína Africana/genética , Filogenia , Análise de Sequência de DNA/veterinária , Surtos de Doenças/veterinária , Genótipo , Hemorragia/epidemiologia , Hemorragia/veterinária , Doenças dos Suínos/epidemiologia
19.
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
20.
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
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