Areas within the United States at the Highest Risk for African Swine Fever, Classical Swine Fever, and Foot-and-Mouth Disease Introduction

Domestic livestock production is a major component of the agricultural sector, contributing to food security and human health and nutrition and serving as the economic livelihood for millions worldwide. The impact of disease on global systems and processes cannot be understated, as illustrated by the effects of the COVID-19 global pandemic through economic and social system shocks and food system disruptions. This study outlines a method to identify the most likely sites of introduction into the United States for three of the most concerning foreign animal diseases: African swine fever (ASF), classical swine fever (CSF), and foot-and-mouth disease (FMD). We first created an index measuring the amount of potentially contaminated meat products entering the regions of interest using the most recently available Agricultural Quarantine Inspection Monitoring (AQIM) air passenger inspection dataset, the AQIM USPS/foreign mail, and the targeted USPS/foreign mail interception datasets. The risk of introduction of a given virus was then estimated using this index, as well as the density of operations of the livestock species and the likelihood of infected material contaminating the local herds. Using the most recently available version of the datasets, the most likely places of introduction for ASF and CSF were identified to be in central Florida, while FMD was estimated to have been most likely introduced to swine in western California and to cattle in northeastern Texas. The method illustrated in this study is important as it may provide insights on risk and can be used to guide surveillance activities and optimize the use of limited resources to combat the establishment of these diseases in the U.S.

Game meat procurement market in Poland in 2009-2021

Procurement of game animals is a major source of revenue for hunting clubs in Poland. For several years, the game meat buying market has been showing an upward trend, but this situation is also influenced by random factors that negatively affect the value of the game meat buying market. For several years in our country we have been struggling with the ASF virus, and since 2020, negative effects in the economy related to the occurrence of the SARS-CoV virus have been observed, also affecting the hunting sector with its activities. The aim of the study was to analyze the dynamics of game meat procurement in Poland in the years 2009-2021. The data concerned the three most important species, namely deer, roe deer and wild boar. The analysis covered the quantity of game meat, procurement value and the average price of game meat depending on animal species. The conducted research confirmed an upward trend in the volume and value of game meat procurement for all the analysed game species. Similarly, the average procurement prices of roe dee and wild boar meat with the exception of red deer, showed an upward trend. The study confirmed the negative impact of the ASF virus and the SARS-CoV-2 virus on the game meat buying market in Poland.

Infectious disease Roundup 2022

This paper describes the epidemiology, prevalence, transmission, prevention and control of some infectious diseases in companion animals, livestock, wild animals and humans in Ontario, Canada, in 2022, including SARS-CoV-2;Echinococcus multilocularis, Leishmania spp. and SARS-CoV-2;antimicrobial stewardship resources;2 cases of rabid dogs imported from Iran (July 2021 and January 2022);prevalence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriacea, Dirofilaria immitis, Brucella canis, canine parainfluenza and adeno- and herpes viruses in dogs recently imported from Asia;Paragonimus kellicotti lung flukes and Streptococcus equi subsp. zooepidemicus in dogs;African swine fever in pet pigs, backyard pigs and wild pigs and blastomycosis in dogs and humans.

Tracing the Origin of Genotype II African Swine Fever Virus in China by Genomic Epidemiology Analysis

The pandemic spread of African swine fever (ASF) has caused serious effects on the global pig industry. Virus genome sequencing and genomic epidemiology analysis play an important role in tracking the outbreaks of the disease and tracing the transmission of the virus. Here we obtained the full-length genome sequence of African swine fever virus (ASFV) in the first outbreak of ASF in China on August 3rd, 2018 and compared it with other published genotype II ASFV genomes including 9 genomes collected in China from September 2018 to October 2020. Phylogenetic analysis on genomic sequences revealed that genotype II ASFV has evolved into different genetic clusters with temporal and spatial correlation since being introduced into Europe and then Asia. There was a strong support for the monophyletic grouping of all the ASFV genome sequences from China and other Asian countries, which shared a common ancestor with those from the Central or Eastern Europe. An evolutionary rate of 1.312 × 10−5 nucleotide substitutions per site per year was estimated for genotype II ASFV genomes. Eight single nucleotide variations which located in MGF110-1L, MGF110-7L, MGF360-10L, MGF505-5R, MGF505-9R, K145R, NP419L, and I267L were identified as anchor mutations that defined genetic clusters of genotype II ASFV in Europe and Asia. This study expanded our knowledge of the molecular epidemiology of ASFV and provided valuable information for effective control of the disease.

Development of an Indirect ELISA Antibodies Detection Method on Tandem-epitope Peptide of African Swine Fever Virus p30 and p54 Proteins.

Here, we report the development of an indirect ELISA antibodies detection method for African swine fever virus (ASFV). Two purified monoclonal antibodies (mAbs) against ASFV p30 and p54 protein were used as targets and a phage-displayed 12-mer peptide library was used to conduct four rounds of biopanning to screen peptide epitopes, then amino acids GGG was used as a linker to synthesize tandem-epitope peptide of ASFV p30 and p54 protein which was used as coating antigen. The optimum reaction conditions of indirect ELISA were determined by chessboard titration, and clinical serum samples were used to evaluate the specificity, sensitivity, stability and conformity of this method. The biopanning experiment indicated that 146PAEPYTT152 was a core domain of the B cell linear epitope of p54 protein. The optimization results of ELISA reaction conditions showed that the tandem-epitope peptide coupled with ovalbumin (OVA) at N-terminal had low background of non-specific serum reaction. And the optimum reaction effect was obtained when the polypeptide antigen was coated with carbonate buffer in 2 mug.mL-1, the serum was diluted 100-fold with blocking solution (1% gelatin solution), and the HRP-antibody was diluted 5 000 times with 0.05% PBST solution. The cut-off value was determined to be 0.339. Furthermore, the results of specificity, sensitivity and stability tests showed that there is no cross-reaction in positive serum samples of classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), porcine parvovirus (PPV) and porcine pseudorabies virus (PRV), the detection limit of ASFV positive sera is 1:1 600, and the method had high repeatability. Finally, Total 320 swine serum samples were detected simultaneously by the present established method and commercial ASFV antibody detection kit. The results showed that the relative specificity and sensitivity of the two methods were 97.6% and 97.3%, respectively. And the coincidence rate was 97.5%. In conclusion, this method showed good specificity, sensitivity, repeatability and coincidence rate, that had the potential value of developing clinical diagnostic kit.Copyright © 2022 Editorial Board, Institute of Animal Science of the Chinese Academy of Agricultural Sciences. All rights reserved.

Disease threats to tigers and their prey

The contraction of the global tiger population over the last 100 years into small, often isolated subpopulations has made them increasingly vulnerable to the impact of disease. Despite this, the health of wild tigers continues to be insufficiently funded and explored. For example, canine distemper virus (CDV), has been associated with localized declines and increased risk of extinction, and yet has received little research attention in most tiger range countries. The emergence of new pathogenic threats has posed fresh challenges, including African swine fever virus (ASFV), which has the potential to devastate wild boar populations, and severe acute respiratory syndrome coronavirus (SARS-CoV2) with implications for tiger conservation that remain unknown. The objective of this review is to synthesize current research on the health of tigers and their prey that impacts the conservation of tigers in the wild. Published sources are interpreted based on three mechanisms through which disease can affect the viability of tiger populations: (1) by reducing the survival of adult tigers, (2) by reducing breeding productivity, and (3) by reducing the carrying capacity of tiger habitat through decreased prey abundance. Examples of CDV, SARS-CoV2, carnivore protoparvovirus 1 and ASFV are used to illustrate these processes and inform discussion of research and mitigation priorities. Copyright © 2023 Gilbert, Dvornicky-Raymond and Bodgener.

Current understanding of the airborne transmission of important viral animal pathogens in spreading disease

Current research on airborne transmission of African swine fever virus (ASFV), porcine epidemic diarrhoea virus (PEDV), avian influenza (AIV), porcine reproductive and respiratory syndrome virus (PRRSV), and foot and mouth disease virus (FMDV) was reviewed to evaluate commonalities, knowledge gaps, and methodologies of studying airborne transmission of animal diseases. The reviewed studies were categorised as short-range transmission (within a single facility) and long-range transmission (beyond a single site). Short-range airborne transmission was demonstrated for at least one strain of the above-mentioned pathogens in experimental settings. Most studies reported in the literature concern FMDV, with limited information for ASFV and PEDV, particularly for short-range airborne transmission. Air sampling upwind, downwind, and within infected facilities has been commonly used to demonstrate long-range airborne transmission. The amount of evidence from air sampling for each of the reviewed viruses varies from no evidence on ASFV to evidence from multiple settings for AIV. Computer modelling has been used to study past outbreaks of infectious diseases to assess the contribution of airborne transmission with a multitude of computer models reported in the literature for simulating long-range airborne transmission of FMDV based on past outbreaks. This has resulted in predictive tools for assessing future risk of airborne transmission. Some important computer models are based on epidemiology analysis, weather analysis, and air dispersion. Few models are reported for ASFV, PEDV, and PRRSV. Studies in the literature indicate that airborne transmission is generally affected by virus strain, aerosol type, shedding duration and concentration, environmental conditions, and infectious dose.

Tradeoff analysis of the pork supply and food security under the influence of African swine fever and the COVID-19 outbreak in China

China is the world's largest consumer of pork and grains. However, African swine fever (ASF) and the COVID-19 outbreak have greatly impacted the pork supply and food security in China. How can food security and the pork supply be ensured under the dual impacts of COVID-19 and ASF? This is a major problem to be urgently solved by the Chinese government. This study indicated that the main pork production and sales areas in China were separated, which reflected the spatial imbalance between the supply and demand. The total area of suitable selected sites for pig farms in China is 21.5 million ha. If only the areas with levels of high and moderate suitability are considered as potential sites for pig farms, the potential pork production can reach 56.1 million tons in China, which is slightly lower than demand. Due to the impact of the ASF epidemic, the food consumed by pigs has been reduced by 34.7 million tons. However, with increasing pork productivity in the future, the self-sufficiency rate of grains may further decline. On the premise that the quality of people's life is not affected, the diversification of meat supply channels should be realized in an orderly and sustainable way, which might alleviate the pressure on food supply. This study provides a theoretical reference for the spatiotemporal layout of the swine industry and addresses the issue of food security in China under the influence of ASF and the COVID-19 outbreak.

Preparation of the Monoclonal Antibody against the African Swine Fever Virus p54 Protein and Identification of the Antigenic Epitope.

The aim of this paper was to prepare specific monoclonal antibody (mAb) against African swine fever virus (ASFV) p54 protein. The p54 protein was expressed in Escherichia coli expression system and used as the antigen in mAb production. The spleen cells from the immunized BALB/c mice were fused with myeloma cells SP2/0. To screen the positive hybridoma cells, the purified p54 protein was used as envelope antigen for indirect ELISA. After four times' subcloning, the supernatant of hybridoma cells were used to identify mAb subtype, ascites were prepared via in vivo induction method in mice and then the mAb was purified. The titer of the mAb was detected by indirect ELISA, and the specificity of the mAb was identified by cross reactivity assay, IFA and Western blot. According to the predicted secondary structure of p54 protein, using the stepwise truncation method identified the epitope region of mAbs, and labeled the region in tertiary structure of p54 protein. Results were as follows: six hybridoma cells secreting p54 monoclonal antibody were successfully screened and named 28G12-1, 31G7-1, 31G7-2, 35F10-1, 35F10-2, 38D3-1, respectively. The heavy chains of 28G12-1, 31G7-1, and 31G7-2 were IgG2a type, the heavy chains of 35F10-1, 35F10-2, 38D3-1 were IgG1 type, light chains were all kappa chains. The lowest titer of mAb was 1:25 600, and having no cross reaction with PRRSV, PRV, PEDV, PPV, SADS-CoV, PCV2, the specificity was strong. All six monoclonal antibodies could recognize the 127-146 aa on carboxyl end. In this study, ASFV p54 protein and p54 monoclonal antibody were successfully obtained, and the epitopes of six mAbs were identified, these experimental data laid a foundation for the functional research of p54 protein and the study of ASFV epitope vaccine. Copyright © 2023 Editorial Board, Institute of Animal Science of the Chinese Academy of Agricultural Sciences. All rights reserved.

Analysis of Spatiotemporal Transmission Characteristics of African Swine Fever (ASF) in Mainland China

In view of the rapid spread of African swine fever in Mainland China from 2018 to 2019, we used spatiotemporal statistical analysis methods to study the spatiotemporal transmission features of African swine fever. The results reveal that the hot spots of African swine fever were concentrated in some cities in Northeast and Southwest China. Seven spatiotemporal clusters of African swine fever were identified, and the most likely spatiotemporal cluster was located in the Buyi and Miao Autonomous Prefecture of QianNan in Guizhou Province, and the cluster date was from 19 June to 25 June 2019. The first secondary cluster covered five cities (Shenyang, Yingkou, Panjin, Anshan, and Liaoyang) in Liaoning Province from 1 August to 10 October 2018. In addition, from the global and local transmission direction and speed of African swine fever in Mainland China, the spatial transmission speed of ASF was found to be slow from August to October 2018, and fast from February to March 2019. Lastly, the global and local isolation and exposure of sites infected with ASF were calculated in Mainland China to reveal the infection risk of different susceptible sites and time periods. [ FROM AUTHOR]

Annual report of the Scientific Network on Animal Health 2022

According to its Founding Regulation (Regulation (EC) No 178/2002), the European Food Safety Authority (EFSA) was tasked to establish a system of networks of organisations operating in the fields within EFSA's remit, with the objective to facilitate a scientific cooperation framework by coordinating activities, exchanging information, developing and implementing joint projects, and exchanging expertise and best practices. The Scientific Network on Risk Assessment in Animal Health and Welfare (AHAW) aims to build a mutual understanding of risk assessment principles in the areas of animal health and welfare, to promote harmonisation of animal health and welfare risk assessment practices and methodologies, and to reduce the duplication of activities by identifying and sharing current and upcoming priorities. The network organises an annual meeting dedicated to animal health‐related issues to discuss and exchange on all topics relevant and interesting to its member organisations. In 2022, this annual meeting took place on 27 and 28 June. Among all topics covered, special attention was paid to avian influenza, African swine fever and SARS‐CoV‐2. One Health surveillance and biosecurity were further highlights in 2022. This report summarises the activities presented by members and observers of the network as well as EFSA's contributions during the meeting.

Descriptive epidemiology and spatial analysis of African swine fever epidemics in Can Tho, Vietnam, 2019.

The objectives of this study were to describe the epidemiology of African swine fever (ASF) and to identify factors that increased commune-level risk for ASF in Can Tho, a province in the Mekong River Delta of Vietnam. In 2019, a total of 2377 of the 5220 pig farms in Can Tho were ASF positive, an incidence risk of 46 (95% CI 44-47) ASF positive farms for every 100 farms at risk. Throughout the outbreak ASF resulted in either the death or culling of 59,529 pigs out of a total population size of 124,516 (just under half of the total pig population, 48%). After the first detection in Can Tho in May 2019, ASF spread quickly across all districts with an estimated dissemination ratio (EDR) of greater than one up until the end of July 2019. A mixed-effects Poisson regression model was developed to identify risk factors for ASF. One hundred unit increases in the number of pigs per square kilometre was associated with a 1.28 (95% CrI 1.05-1.55) fold increase in commune-level ASF incidence rate. One unit increases in the number of pig farms per square kilometre was associated with a 0.91 (95% CrI 0.84-0.99) decrease in commune-level ASF incidence rate. Mapping spatially contiguous communes with elevated (unaccounted-for) ASF risk provide a means for generating hypotheses for continued disease transmission. We propose that the analyses described in this paper might be run on an ongoing basis during an outbreak and disease control efforts modified in light of the information provided.

Berbamine Hydrochloride Inhibits African Swine Fever Virus Infection In Vitro.

African swine fever virus (ASFV) causes a viral disease in swine with a mortality rate of approximately 100%, threatening the global pig industry's economic development. However, vaccines are not yet commercially available, and other antiviral therapeutics, such as antiviral drugs, are urgently needed. In this study, berbamine hydrochloride, a natural bis-benzylisoquinoline alkaloid isolated from the traditional Chinese herb Berberis amurensis, showed significant antiviral activity against ASFV. The 50% cytotoxic concentration (CC50) of berbamine hydrochloride in porcine alveolar macrophages (PAMs) was 27.89 µM. The antiviral activity assay demonstrated that berbamine hydrochloride inhibits ASFV in a dose-dependent manner. In addition, a 4.14 log TCID50 decrease in the viral titre resulting from non-cytotoxic berbamine hydrochloride was found. Moreover, the antiviral activity of berbamine hydrochloride was maintained for 48h and took effect at multiplicities of infection (MOI) of 0.01, 0.1, and 1. The time-of-addition analysis revealed an inhibitory effect throughout the entire virus life-cycle. A subsequent viral entry assay verified that berbamine hydrochloride blocks the early stage of ASFV infection. Moreover, similar anti-ASFV activity of berbamine hydrochloride was also found in PK-15 and 3D4/21 cells. In summary, these results indicate that berbamine hydrochloride is an effective anti-ASFV natural product and may be considered a novel antiviral drug.

Shocks, cycles and adjustments: The case of China's Hog Market under external shocks

China's hog market has faced the challenge of several external shocks, which arise from the ongoing COVID-19 pandemic, African Swine Fever (ASF) and related global trade uncertainties. This article develops a shocks, cycles and adjustments (SCA) model to evaluate the dynamic impact of different shock scenarios. The SCA model contributes to the existing toolbox for impact evaluation in commodity markets and provides insights into the timing of impact dynamics at refined time intervals. The SCA model is applied to evaluate five sets of shock scenarios, which include a demand shock, a corn price increase, pork import restrictions, a second wave of ASF, and a combination of these shocks. Simulation results demonstrate the reaction of the hog cycle to different shocks with quantitive outcomes. Based on the simulation results, we find that production and economic adjustment lags generate constant and predictable hog cycles, while the external shocks lead hog cycles to be irregular with varying phase and amplitude. [EconLit Citations: Q10, Q11]. © 2022 Wiley Periodicals LLC.

How does imported pork regulate the supply and demand of China's pig market during the epidemic?-based on the analysis of African swine fever and COVID-19.

The pig industry is primarily a domestic industry in China is focused on ensuring the domestic pork supply. This paper analyzed changes in Chinese pork imports following the outbreaks of African Swine Fever (ASF) and COVID-19 between January 2017 to November 2020 and evaluated the impact of imported pork on the development of the swine industry in China. The results demonstrated that the shortage of domestic pork supply changed the import volume. ASF transformed imported pork from a complementary product to meet the diversified needs of domestic consumers into a critical substitute required to fill the supply gap. Following the COVID-19 outbreak, the substitution effect of imported pork decreased. ASF, has caused the supply capacity of pork in China to decrease, the price of pork to increase, leading to increased pork import in January 2019. At the end of 2019, pig slaughter decreased, while China cut tariffs on imported pork. The COVID-19 outbreak did not reduce China's pork imports in China, which declined after the global COVID-19 outbreak. Imported pork has made up for the supply gap during COVID-19, not impacting the level of production of the swine industry in China.

The perceptions of Lithuanian hunters towards African swine fever using a participatory approach.

BACKGROUND: African swine fever (ASF) has been present in Lithuania since 2014. The disease affects mainly the wild boar population. Thus, hunters play a key role in the performance of disease surveillance and control measures. We used participatory methods to gain insight into the knowledge of hunters and to include their perceptions in the design and the implementation of surveillance and control measures to increase their effectiveness. RESULTS: The willingness and the interest of hunters to participate was high, but only eight focus group meetings with 33 hunters could be held due to the COVID-19 pandemic. The overall knowledge of Lithuanian hunters regarding ASF, investigated by semi-structured interviews, was sufficient to understand their part in ASF control and surveillance. However, their knowledge did not necessarily lead to an increased acceptance of some ASF control measures, like the targeted hunting of female wild boar. Participating hunters showed a good understanding of the processes of the surveillance system. Their trust in the performance within this system was highest towards the hunters themselves, thus emphasizing the importance of acknowledging their role in the system. Hunters refused measures including the reduction of hunting activities. They feared a complete elimination of the wild boar population, which in turn demonstrates the necessity to increase professional information exchange. CONCLUSIONS: The perceptions of Lithuanian hunters regarding ASF surveillance and control in wild boar resembled those obtained in neighboring countries. It is imperative to communicate the results with decision-makers, to consider the views of hunters, when designing or adapting measures to control ASF in wild boar and to communicate with hunters on these measures and their justification.

Epidemics and pandemics of infectious disease

Throughout the course of civilization, epidemics and pandemics have ravaged humanity, destroyed animal breeding and horticulture, and has also changed the course of history. It has been estimated that Justinian plague has affected half of the population of Europe and killed in three pandemics 50 million people, the avian-borne flu (Spanish flu), resulted in 50 million deaths worldwide in the years 1918-1919, and recently the COVID-19 is officially a pandemic, after barreling through 114 countries in just three months. In the past, rinderpest has hit Europe with three long panzootics, African swine fever (ASF), is still a threat to both the swine production industry and the health of wild boar populations. Several molecular changes occur in the pathogen that may trigger an epidemic or even pandemic. These include increase of virulence, introduction into a novel host, and changes in host susceptibility to the pathogen. Once the infectious disease threat reaches an epidemic or pandemic level, the goal of the response is to mitigate its impact and reduce its incidence, morbidity and mortality as well as disruptions to economic, political, and social systems. An epidemic curve shows progression of illnesses in an outbreak over time and the SIR, SI, SIRD and SEIR represent the simplest compartmental models that enable simplify the mathematical modelling of epidemics. This article throws a light on changing ideas in epidemiology of infectious diseases.

One-Pot Visual Detection of African Swine Fever Virus Using CRISPR-Cas12a.

African swine fever virus (ASFV) is a leading cause of worldwide agricultural loss. ASFV is a highly contagious and lethal disease for both domestic and wild pigs, which has brought enormous economic losses to a number of countries. Conventional methods, such as general polymerase chain reaction and isothermal amplification, are time-consuming, instrument-dependent, and unsatisfactorily accurate. Therefore, rapid, sensitive, and field-deployable detection of ASFV is important for disease surveillance and control. Herein, we created a one-pot visual detection system for ASFV with CRISPR/Cas12a technology combined with LAMP or RPA. A mineral oil sealing strategy was adopted to mitigate sample cross-contamination between parallel vials during high-throughput testing. Furthermore, the blue fluorescence signal produced by ssDNA reporter could be observed by the naked eye without any dedicated instrument. For CRISPR-RPA system, detection could be completed within 40 min with advantageous sensitivity. While CRISPR-LAMP system could complete it within 60 min with a high sensitivity of 5.8 × 102 copies/µl. Furthermore, we verified such detection platforms display no cross-reactivity with other porcine DNA or RNA viruses. Both CRISPR-RPA and CRISPR-LAMP systems permit highly rapid, sensitive, specific, and low-cost Cas12a-mediated visual diagnostic of ASFV for point-of-care testing (POCT) applications.

Porcine coronavirus: what are the scientific advances? [French]

Coronaviruses have a high evolutionary capacity which has led to their very large genetic diversity. Their prevalence in nature is very high and they can infect a wide spectrum of hosts including mammals (including humans) and birds. To date, six porcine coronaviruses have been identified. Two of which were responsible for severe epizootics in pigs with a major impact in the global swine industry in the 60's to 80's for porcine transmissible gastroenteritis virus and since the 2010's in China and 2014 in North America for porcine epidemic diarrhoea virus. The latter has also become the third most important pathogen for pigs in China after the African swine fever virus and the porcine reproductive and respiratory syndrome virus. This review summarizes the latest developments in scientific knowledge of these porcine coronaviruses.