African swine fever virus

In 2007 African swine fever (ASF) entered Georgia and in the same year the disease entered the Russian Federation. From 2007 to 2012 ASF spread throughout the southern region of the Russian Federation. At the same time several cases of ASF were detected in the central and northern regions of the Russian Federation, forming a northern cluster of outbreaks in 2011. This northern cluster is of concern because of its proximity to mainland Europe. The aim of this study was to use details of recorded ASF outbreaks and human and swine population details to estimate the spatial distribution of ASF risk in the southern region of the European part of the Russian Federation. Our model of ASF risk was comprised of two components. The first was an estimate of ASF suitability scores calculated using maximum entropy methods. The second was an estimate of ASF risk as a function of Euclidean distance from index cases. An exponential distribution fitted to a frequency histogram of the Euclidean distance between consecutive ASF cases had a mean value of 156 km, a distance greater than the surveillance zone radius of 100–150 km stated in the ASF control regulations for the Russian Federation. We show that the spatial and temporal risk of ASF expansion is related to the suitability of the area of potential expansion, which is in turn a function of socioeconomic and geographic variables. We propose that the methodology presented in this paper provides a useful tool to optimize surveillance for ASF in affected areas.

African swine fever is the viral disease of pigs that can lead up to 100% mortality among infected animals and causes huge economic losses in the Russian Federation. The space-time analysis of the disease spread conducted by means of ArcGIS tools allowed to develop a model that detects a high risk area of the infection diffusion from an affected site. Recommendations for veterinary services were proposed to improve preventive measures by adjusting sizes and shapes of surveillance zones.

African swine fever (ASF) is a very serious disease that affects members of the Suidae family. ASF first appeared in the sub-Saharan region of Africa [1], and from there the disease spread across the Transcaucasian region to Europe and Asia. There is a growing concern that the disease will spread to other areas because of travel and imports of pork products from countries where ASF is present. The causative agent of ASF is an enveloped cytoplasmic double-stranded DNA arbovirus (Asfavirus) (genome size 170–193 kbp), which is the only member of the Asfarviridae family. The natural cycle of ASF virus (ASFV) spread occurs only in some parts of Africa and in the Iberian Peninsula. The first case of an outbreak of ASF in China was reported at a suburban pig farm in Shenyang in 2018. The low concentration of viruses in environmental samples makes detection extremely difficult. Therefore, simple, accurate and fast detection methods are urgently needed. Portable detectors based on biological molecules could be very helpful for rapid diagnosis in an outbreak. The aim of this work is to verify the possibilities of direct capture of DNA on magnetic nanoparticles and subsequent detection of DNA using electrochemical methods.

African Swine Fever Virus (ASFV) is a dsDNA virus causative of the African Swine Fever (ASF) in wild and domestic hogs. ASF is characterized by hemorrhagic fever, high mortality, and transmissibility. The binding of the DNA to the pA104R protein mediates viral replication and genome packaging. In the present study, we generated nine (9) reference compounds that exhibited high docking affinities through de novo computeraided drug design (CADD). These compounds were then used as query molecules to find commercially available drug-like compounds using ligand-based virtual screening (VS). We were able to retrieve 900 hit compounds that exhibited the same pharmacophoric activities. Then, these hit compounds were subjected to drug-likeness filtration to identify the most likely to be developed as commercial drugs based on established parameters. We identified sixty-two (62) drug-like molecules. Molecular docking was then performed to determine the top five compounds with the highest binding affinities against the target protein. ADME/T profiling was done on these compounds to assess their pharmacokinetic properties. Compound 8.45 performed best based on our devised scoring system. This paper shall serve as a good reference in the discovery and development of anti-ASFV therapeutics.

African Swine Fever (ASF) is a viral infection which causes acute disease in domestic pigs and wild boar. Although the virus does not cause disease in humans, the impact it has on the economy, especially through trade and farming, is substantial causing more than one billion EUR yearly losses in Eastern Europe and dozens of billions globally. Thus, ASF is a possible biological weapon, due to: ease of infectious material collection; its extremely high virulence; multiple transmission route mechanisms; no treatment and no vaccine; its high resistance to inactivation and devastating impact on pork production.
In our theoretical model, a single person without any special training in microbiology or financing support could release and disseminate ASF virus to disease free territory.  In contrast to other biological weapons as Bacillus anthracis or Variola virus (the respective causative agents of anthrax and smallpox), terrorist could access virus easily, e.g. by collecting infectious materials from wild boar carcasses. Sample preparation is simple and does not require any sophisticated laboratory equipment. Recent development of portable ASF virus detection kits in middle of 2019 in China increased feasibility of attack, because until now material diagnosis was the weakest point in possible intentional introduction protocols. Such a contaminated material could easily be used for infection of swine or wild boars in new disease-free territory and seed a new outbreak.
We conclude that rising awareness about the ease of an intentional ASF introduction to a disease-free region (via bioterrorism) is an important element of security strengthening and recommend the use of modeling approach for risk assessment as well its experimental validation of the international ASF dissemination.
This analysis does not include external confidential attachment that contains a secret information (possible infection introduction protocols with demonstrated case studies), when unauthorized disclosure of the information could cause damage to the national and international security.

African Swine Fever (ASF) is a viral infection which causes acute disease in Sus scrofa – domestic pigs and wild boar. Although the virus does not cause disease in humans, the impact it has on the economy, especially via trade and farming disturbance, is substantial. We analyze 3487 ASF notifications of wild boars and pigs in Poland (infection events registered to OiE) from February 2014 to April 2019 comprising event time, longitude, latitude and administrative unit: county/poviat. We propose a spatial modeling approach incorporating phenomenological analysis of multilayer transmission networks: 1) domestic pig abundance, 2) disease vectors (wild boar) abundance, 3) human mobility related to disease propagation. We use a pseudo gravity model to simulate the future epidemic projection and calculated the most probable infection paths for all counties (poviats) as well as estimated the most likely disease arrival times with or without countermeasures such as border fencing and animals corridors blocking on the A1 motorway. According to current observation, the ASF spread in Poland will be ongoing and recent jumps to wschowski poviat 320 km from the closest previously affected area manifests its complex behavior. The proposed complex network approach promise to be useful to practioners, farmers and veterinarians, helping them to choose the optimal mitigation strategies.

Afrykański pomór świń (ASF) jest zakaźną chorobą wirusową trzody chlewnej oraz dzików, która nie zagraża ludziom, jednak występowanie pomoru wiąże się z ogromnymi kosztami dla rynku trzody chlewne o znacznej wartości rynku (ok 20 mld PLN) w Polsce. Wirus ASF 14.11.2019 został potwierdzony u dzika w powiecie wschowskim w odległości mniejszej niż 50km of hubu produkcji trzody chlewnej w Wielkopolsce (tzw. „świński róg”) a pojawienie się tam ASF-u  może spowodować niepokoje społeczne na niespotykaną w III RP skalę.
Ze względu na brak zagrożenia zdrowia ludzi, zainteresowanie tematem jest niewielkie mimo spowodowanych już głębokich zmian w aspekcie ekonomicznym (np. spadek pogłowia świń – na Ukrainie prawie 3-krotny, ogólnoświatowe braki w zaopatrzeniu leków do produkcji których wykorzystuje się świnie), społecznym (np. masowe protesty w Europie Wschodniej) czy kulturowym (np. wieprzowina od kwietnia 2019 nie jest już najczęściej spożywanym mięsem globalnie). Celowe wprowadzenie może nastąpić na skalę: jednego powiatu (np. ze wschodniej Polski do zachodniej Polski); wewnątrzkontynentalny (np. ze wschodniej do zachodniej Europy); międzykontynentalny (np. z Chin do USA).

BULLET POINT SUMMARY
 COVID‐19 Coronavirus is as much an ecological disaster as it is a medical
one. Initially it appears to be a unique experience centered in Wuhan,
China. It emanates from an environment of incinerated pig waste, airborne
particles, and low vitamin D blood levels in winter, and weakened immune
systems, particularly among smokers, drinkers and the elderly.
 It is believed both the Spanish flu of 1918 and the COVID‐19 coronavirus
began as zoonotic (animal to human) infections. Not from bats as first
reported in the Wuhan COVID‐19 outbreak, but rather from pigs, and pig
waste.
 The 1918 Spanish flu pandemic began in the midst of an infectious pig
slaughter of undiscovered cause, a few hundred miles from Camp Funston,
what is Fort Riley today. Similarly, the outbreak of the COVID‐19
coronavirus outbreak began in the Wuhan, China area in the wake of a
massive kill‐off of pigs who were dying from African Swine Flu.
 Viral outbreaks arise in winter, but so does tuberculosis.
 Some types of mycobacteria do not have cell walls and can mimic the
appearance of a virus under the microscope.
 Antibiotics cannot be used for viruses. If a virus, then why aren’t antiviral
drugs working but antibiotics are?
 COVID‐19 coronavirus may just be a “passenger virus,” not the primary
microbial organism that kills by filling the lower lungs with fluid.
 Both the current Wuhan COVID‐19 coronavirus and tubercular
mycobacteria do not tend to infect or cause serious disease in young
children roughly 5‐12 years of age.
 Fear of the COVID‐19 coronavirus may be misplaced. More people are
killed by Mycobacterium tuberculosis (1.7 million) in a year than the few
who have been infected (~80,000) or have died (less than 2000) of the
COVID‐19 coronavirus.
 It is projected that the "COVID‐19 Coronavirus" will peak worldwide in
March and then return in a second but lesser peak in September, in
accordance with Yang’s Wuhan study from 2004 to 2013, describing the
annual TB surges in Wuhan, China.

African swine fever (ASF) is a devastating haemorrhagic fever of pigs that causes up to 100% mortality, for which there is no vaccine. It is caused by a unique DNA virus that is maintained in an ancient cycle between warthogs and argasid ticks, making it the only known DNA arbovirus. ASF has a high potential for transboundary spread, and has twice been transported from Africa to other continents--Europe and subsequently the Caribbean and Brazil (1957, 1959) and the Caucasus (2007). It is also a devastating constraint for pig production in Africa. Research at Onderstepoort Veterinary Institute has made and is making important contributions to knowledge of this disease, focusing on the cycle in warthogs and tampans and transmission from that cycle to domestic pigs, resistance to its effects in domestic pigs, and the molecular genetic characterisation and epidemiology of the virus.

African swine fever (ASF) has recently made its appearance in Madagascar. Ticks of the Ornithodoros moubata group, considered to be O. porcinus Walton, 1962 were formerly known to occur in western Madagascar, but seem to have disappeared from that region. However, three new sites where they occur were found in the humid and cool central highlands of Anatananarivo province. These ticks are known to be efficient reservoirs and vectors of ASF and constitute a considerable complication to the control of the disease. The authors also discuss another potentially complicating factor, the presence of a species of African bushpig, Potamochoerus larvatus.

The present study is the first report on the functional activity of a parapoxvirus-encoded dUTPase. The dUTPase gene of the attenuated orf virus (ORFV), strain D1701, was expressed as a bacterial thioredoxin fusion protein. In vitro assays showed that ORFV dUTPase was highly specific for dUTP as substrate. The enzyme was active over a broad pH range (pH 6.0-9.0), with maximal enzymatic activity at pH 7.0 in the presence of Mg(2+) cations. Kinetic studies of the recombinant ORFV dUTPase revealed an apparent K(m) of 4.0 microM, which is more similar to that of the mammalian or African swine fever virus enzyme than to the K(m) of vaccinia virus dUTPase. Enzyme activity was also found with purified ORFV particles, indicating its virion association.

African swine fever (ASF), have been introduced into the Russian Federation from Tran-scaucasia countries, has spread widely across the territory of the southern region of Russia since 2008. In this work we present an analysis of the spatial and temporal spread of the disease , determine risk factors by means of GIS tools and model the dynamics of the epidemic process both within infected premises (farms) and at the between-farm level to estimate the basic reproduction ratio R 0. The analysis allowed us to make a conclusion about the anthropogenic nature of the risk factors for disease spread. The major significant risk factors identified were: density of the road network, density of domestic swine population and density of water bodies in the study area. The basic reproduction ratio was estimated to range from 2 to 3 at the between-farm level and from 8 to 11 within the infected farms. These initial studies of the ASF epidemic provide information on which to based control and prevention programs.

African swine fever virus (ASFV) is the only known DNA arbovirus and the sole member of the family Asfarviridae. It causes a lethal, hemorrhagic disease in domestic pigs. ASFV is enzootic in sub-Saharan Africa and is maintained in a sylvatic cycle by infecting both wild members of the Suidae (e.g. warthogs) and the argasid tick Ornithodoros porcinus porcinus. The pathogenesis of ASFV in O. porcinus porcinus ticks is characterized by a low infectious dose, lifelong infection, efficient transmission to both pigs and ticks, and low mortality until after the first oviposition. ASFV pathogenesis in warthogs is characterized by an inapparent infection with transient, low viremic titers. Thus O. porcinus porcinus ticks probably constitute the most important natural vector of ASFV, although both the mammalian and tick hosts are probably required for the maintenance of ASFV in the sylvatic cycle. The mechanism of ASFV transmission from the sylvatic cycle to domestic pigs is probably through ...

With few exceptions, the diseases that present the greatest risk to food animal production have been largely similar throughout the modern era of veterinary medicine. The current trend regarding the ever-increasing globalization of the trade of animals and animal products ensures that agricultural diseases will continue to follow legal and illegal trade patterns with increasing rapidity. Global climate changes have already had profound effects on the distribution of animal diseases, and it is an inevitable reality that continually evolving climatic parameters will further transform the ecology of numerous pathogens. In recent years, many agricultural diseases have given cause for concern regarding changes in distribution or severity. Foot-and-mouth disease, avian influenza, and African swine fever continue to cause serious problems. The expected announcement of the global eradication of rinderpest is one of the greatest successes of veterinary preventative medicine, yet the closely ...

The open reading frame EP153R, located within the EcoRI E′ fragment of the African swine fever (ASF) virus genome, is predicted to encode a membrane protein of 153 amino acids that presents significant homology to the N-terminal region of several CD44 molecules. EP153R contains multiple putative sites for N-glycosylation, phosphorylation, and myristoylation, a central transmembrane region, a C-type animal lectin-like

Introduction
This research is devoted to the estimation of basic reproductive ratio (R0) of African swine fever (ASF) in domestic pigs at within- as well as between-holdings level. Recently published detailed data on pigs’ mortality during the ASF outbreak in Odessa region of the Ukraine in 1977 were used for estimation of R0. The epidemic has affected 20 settlements, in which domestic pigs were infected both at large farms and at private backyards. Timely application of control measures allowed successful eradication of the epidemic and prevention of further spread of the virus.

Methods
The method of early exponential-growth rate based on the analysis of an epidemic curve was chosen for estimation of R0. The course of epidemic within farm at Usatovo village demonstrates three epidemic waves that could be caused by consecutive infection of pigs from one pigpen to another. An exponential curve was fitted to the initial phase of each wave followed by calculation of R0 by simulation of infection period’s duration using Monte-Carlo method. Similarly, an exponential curve was fitted to the incidence data at between-farm level. The period of time from the date of symptoms onset at the farm to the date of confirmation of diagnosis and applying quarantine measures was taken as an infectious period.

Results
The modeling estimates a basic reproductive ratio within an infected farm as 5.9 (2.3 – 12.8), and at between-farm level as 2.0 (1.1 – 4.9). The values are consistent with the results obtained by other authors.

Discussion
Detailed data on natural dynamics of mortality, particularly within affected farm, are rarely available and, thus, are especially valuable. Results of the work have importance for understanding of the ASF epidemic process from practical point of view since they can help preventing the spread of the disease at different levels more effectively.

INTRODUCTION: In 2007, African swine fever virus (ASFv) broken its well-known boundaries. This was the reference year for the first report of African swine fever (ASF) in Georgia. Subsequently, the virus reached pigs and boars in Armenia and Russia. From the Caucasus area, ASFv jumped in all directions, between the Black Sea and the Caspian Sea, in relation to the density of backyard pigs and their trade. In the next ten years there have been notifications and registrations of ASFv outbreaks in Russia, Azerbaijan, Ukraine, Belarus, Lithuania, Poland, Estonia, Latvia, Moldova and the Czech Republic. Romania faced the first ASFv outbreak at the end of July 2017, in backyard pigs." in stead "density of backyard pigs and their trade. In the next ten years there have been notifications and registrations of ASFv outbreaks in Russia, Azerbaijan, Ukraine, Belarus, Lithuania, Poland, Estonia, Latvia, Moldova and the Czech Republic. Romania faced the first ASFv outbreak at the end o...

Recently moderate-virulence classical swine fever virus (CSFV) strains have been proven capable of generating postnatal persistent infection (PI), defined by the maintenance of viremia and the inability to generate CSFV-specific immune responses in animals. These animals also showed a type I interferon blockade in the absence of clinical signs. In this study, we assessed the infection generated in 7-week-old CSFV PI wild boars after infection with the African swine fever virus (ASFV). The wild boars were divided in two groups and were infected with ASFV. Group A comprised boars who were CSFV PI in a subclinical form and Group B comprised pestivirus-free wild boars. Some relevant parameters related to CSFV replication and the immune response of CSFV PI animals were studied. Additionally, serum soluble factors such as IFN-α, TNF-α, IL-6, IL-10, IFN-γ and sCD163 were analysed before and after ASFV infection to assess their role in disease progression. After ASFV infection, only the CSF...

Aim: First cases of clinically uncommon African swine fever (ASF), caused by virus genotype II are described in this article. These cases occurred in Armenia, Tavush region, Dilijan municipality in 2011. The aim of this study was to identify and describe the new pathogenic forms of ASF in Armenia. Materials and Methods: The isolation and identification of ASF virus (ASFV) were carried out using conventional techniques. Clinical signs of infection were recorded daily. Gross anatomical pathology characteristics were observed during routine postmortem examinations. Blood and serum were obtained by puncture of the jugular vein using a vacutainer system. Results: The presence of ASFV DNA in the spleens was confirmed by polymerase chain reaction. Sequenced sections of p72 showed phylogenetic identity to genotype 2. The pathology exhibits unusual manifestations of the main disease. The unusual form of ASF demonstrates characteristics of a subacute form of the disease, with the possibility of conversion to a chronic form. Decreased lethality, low level of hemorrhages, and absence of severe pancytopenia in smears from spleen, lymph nodes, and blood are common features of the new form of ASF. Unlike severe thrombocytopenia in the typical ASF, the unusual form exhibited moderate or minor decrease of this feature. Despite a moderate decrease in hemadsorption titers, the unusual pattern of the disease was characterized by viremia and the presence of the virus in the visceral organs, including the brain. Conclusion: Our data allow assuming that new nosological form of ASF (genotype II) may present as a transitional form of the disease with the possibility of chronization.

A real-time polymerase chain reaction (PCR) assay for the rapid detection of African swine fever virus (ASFV), multiplexed for simultaneous detection of swine beta-actin as an endogenous control, has been developed and validated by four National Reference Laboratories of the European Union for African swine fever (ASF) including the European Union Reference Laboratory. Primers and a TaqMan® probe specific for ASFV were selected from conserved regions of the p72 gene. The limit of detection of the new real-time PCR assay is 5.7–57 copies of the ASFV genome. High accuracy, reproducibility and robustness of the PCR assay (CV ranging from 0.7 to 5.4%) were demonstrated both within and between laboratories using different real-time PCR equipments. The specificity of virus detection was validated using a panel of 44 isolates collected over many years in various geographical locations in Europe, Africa and America, including recent isolates from the Caucasus region, Sardinia, East and West Africa. Compared to the OIE-prescribed conventional and real-time PCR assays, the sensitivity of the new assay with internal control was improved, as demonstrated by testing 281 field samples collected in recent outbreaks and surveillance areas in Europe and Africa (170 samples) together with samples obtained through experimental infections (111 samples). This is particularly evident in the early days following experimental infection and during the course of the disease in pigs sub-clinically infected with strains of low virulence (from 35 up to 70 dpi). The specificity of the assay was also confirmed on 150 samples from uninfected pigs and wild boar from ASF-free areas. Measured on the total of 431 tested samples, the positive deviation of the new assay reaches 21% or 26% compared to PCR and real-time PCR methods recommended by OIE.This improved and rigorously validated real-time PCR assay with internal control will provide a rapid, sensitive and reliable molecular tool for ASFV detection in pigs in newly infected areas, control in endemic areas and surveillance in ASF-free areas.► A new real-time PCR assay was evaluated for detection of African swine fever virus. ► The new assay includes an internal endogen control targeting swine beta-actin. ► Sensitivity, specificity and reliability in ASF detection have been demonstrated. ► The sensitivity has been improved compared to the OIE recommended PCR methods. ► The assay is suitable for detection of inapparent virus carrier animals.