Exploring type I interferon pathway: virulent vs. attenuated strain of African swine fever virus revealing a novel function carried by MGF505-4R.

African swine fever virus represents a significant reemerging threat to livestock populations, as its incidence and geographic distribution have surged over the past decade in Europe, Asia, and Caribbean, resulting in substantial socio-economic burdens and adverse effects on animal health and welfare. In a previous report, we described the protective properties of our newly thermo-attenuated strain (ASFV-989) in pigs against an experimental infection of its parental Georgia 2007/1 virulent strain. In this new study, our objective was to characterize the molecular mechanisms underlying the attenuation of ASFV-989.

Oronasal or Intramuscular Immunization with a Thermo-Attenuated ASFV Strain Provides Full Clinical Protection against Georgia 2007/1 Challenge.

African swine fever (ASF) is a contagious viral disease of suids that induces high mortality in domestic pigs and wild boars. Given the current spread of ASF, the development of a vaccine is a priority. During an attempt to inactivate the Georgia 2007/1 strain via heat treatment, we fortuitously generated an attenuated strain called ASFV-989.

[Modulation of the innate immune response by African swine fever virus].

African swine fever (ASF) is a highly pathogenic disease causing haemorrhagic fever in domestic and wild swine. It is responsible for numerous epizootics, particularly in Europe and Asia, causing major economic losses for the pig industry. African Swine Fever virus (ASFV) is the etiological agent responsible for this disease.

[Classical swine fever (CSF): towards new challenges].

Classical swine fever (CSF) is a highly contagious swine-specific disease which may have a huge economic impact for porcine production. CSF is caused by a virus belonging to the Pestivirus genus, which has expanded for the past 5 years with the discovery of new species whose genetic proximity to the CSF virus could further complicate laboratory diagnosis. The various forms of the disease, and in particular the increased frequency of attenuated forms, linked to an evolution of CSF virus strains towards a reduction in their virulence, delay clinical diagnosis.

Quantification of ASFV DNA and RNA in Ornithodoros Soft Ticks.

Molecular biology methods are highly sensitive to detect the genome of pathogens and to study their biology. Polymerase chain reaction (PCR) and reverse transcription followed by a polymerase chain reaction (RT-PCR) permit the detection of the presence and the replication of African swine fever virus in soft ticks. Here, we described our techniques to detect and quantify DNA and RNA of African swine fever virus in soft ticks including a housekeeping gene of soft ticks as internal control.

Differential vector competence of Ornithodoros soft ticks for African swine fever virus: What if it involves more than just crossing organic barriers in ticks?

Background: Several species of soft ticks in genus Ornithodoros are known vectors and reservoirs of African swine fever virus (ASFV). However, the underlying mechanisms of vector competence for ASFV across Ornithodoros species remain to be fully understood. To that end, this study compared ASFV replication and dissemination as well as virus vertical transmission to descendants between Ornithodoros moubata, O.

Mechanical transmission of African swine fever virus by Stomoxys calcitrans: Insights from a mechanistic model.

African swine fever (ASF) represents a global threat with huge economic consequences for the swine industry. Even though direct contact is likely to be the main transmission route from infected to susceptible hosts, recent epidemiological investigations have raised questions regarding the role of haematophagous arthropods, in particular the stable fly (Stomoxys calcitrans). In this study, we developed a mechanistic vector-borne transmission model for ASF virus (ASFV) within an outdoor domestic pig farm in order to assess the relative contribution of stable flies to the spread of the virus.

Evaluation of un-methylated DNA enrichment in sequencing of African swine fever virus complete genome.

African swine fever is a febrile hemorrhagic fever disease that is caused by the African swine fever virus (ASFV) and is lethal for domestic pigs and wild boar. ASFV also infects soft ticks of the genus Ornithodoros, some species of which can act as a vector for ASFV. Whole genome sequencing of ASFV is a challenge because, due to the size difference of the host genome versus the viral genome, the higher proportion of host versus virus DNA fragments renders the virus sequencing poorly efficient.

An expert opinion assessment of blood-feeding arthropods based on their capacity to transmit African swine fever virus in Metropolitan France.

To deal with the limited literature data on the vectorial capacity of blood-feeding arthropods (BFAs) and their role in the transmission of African swine fever virus (ASFV) in Metropolitan France, a dedicated working group of the French Agency for Food, Environmental and Occupational Health & Safety performed an expert knowledge elicitation. In total, 15 different BFAs were selected as potential vectors by the ad hoc working group involved. Ten criteria were considered to define the vectorial capacity: vectorial competence, current abundance, expected temporal abundance, spatial distribution, longevity, biting rate, active dispersal capacity, trophic preferences for Suidae, probability of contact with domestic pigs and probability of contact with wild boar.

Putative Role of Arthropod Vectors in African Swine Fever Virus Transmission in Relation to Their Bio-Ecological Properties.

African swine fever (ASF) is one of the most important diseases in Suidae due to its significant health and socioeconomic consequences and represents a major threat to the European pig industry, especially in the absence of any available treatment or vaccine. In fact, with its high mortality rate and the subsequent trade restrictions imposed on affected countries, ASF can dramatically disrupt the pig industry in afflicted countries. In September 2018, ASF was unexpectedly identified in wild boars from southern Belgium in the province of Luxembourg, not far from the Franco-Belgian border.

Coding-Complete Genome Sequence of an African Swine Fever Virus Strain Liv13/33 Isolate from Experimental Transmission between Pigs and Ornithodoros moubata Ticks.

Here, we report the coding-complete genome sequence of African swine fever (ASF) virus strain Liv13/33, isolated from experimentally infected pigs and ticks. The 11 sequences that we obtained harbored no notable differences to each other, and all of them were closely related to the genome sequence of the Mkuzi 1979 strain of genotype I.

Successful Infection of Domestic Pigs by Ingestion of the European Soft Tick That Fed on African Swine Fever Virus Infected Pig.

African swine fever is a highly lethal hemorrhagic fever of , threatening pig production globally. can be infected by different ways like ingestion of contaminated feed, direct contact with infected animals or fomites, and biting by infected soft tick bites. As already described, European soft ticks ( and ) were not able to transmit African swine fever virus by biting pigs although these ticks maintained the infectious virus during several months; therefore, the possibility for pigs to become infected through the ingestion of infected ticks was questioned but not already explored.

No Experimental Evidence of Co-Feeding Transmission of African Swine Fever Virus between Soft Ticks.

soft ticks are the only known vector and reservoir of the African swine fever virus, a major lethal infectious disease of . The co-feeding event for virus transmission and maintenance among soft tick populations has been poorly documented. We infected , a known tick vector in Africa, with an African swine fever virus strain originated in Africa, to test its ability to infect through co-feeding on domestic pigs.

Assessment of the impact of forestry and leisure activities on wild boar spatial disturbance with a potential application to ASF risk of spread.

In Europe, African swine fever virus (ASFV) is one of the most threatening infectious transboundary diseases of domestic pigs and wild boar. In September 2018, ASF was detected in wild boar in the South of Belgium. France, as a bordering country, is extremely concerned about the ASF situation in Belgium, and an active preparedness is ongoing in the country.

Comparative vector competence of the Afrotropical soft tick Ornithodoros moubata and Palearctic species, O. erraticus and O. verrucosus, for African swine fever virus strains circulating in Eurasia.

African swine fever (ASF) is a lethal hemorrhagic disease in domestic pigs and wild suids caused by African swine fever virus (ASFV), which threatens the swine industry globally. In its native African enzootic foci, ASFV is naturally circulating between soft ticks of the genus Ornithodoros, especially in the O. moubata group, and wild reservoir suids, such as warthogs (Phacochoerus spp.

Comparative analysis of the fecal microbiota from different species of domesticated and wild suids.

Most of the microorganisms living in a symbiotic relationship in different animal body sites (microbiota) reside in the gastrointestinal tract (GIT). Several studies have shown that the microbiota is involved in host susceptibilities to pathogens. The fecal microbiota of domestic and wild suids was analyzed.

An Update on African Swine Fever Virology.

Animal diseases constitute a continuing threat to animal health, food safety, national economy, and the environment. Among those, African swine fever (ASF) is one of the most devastating viruses affecting pigs and wild suids due to the lack of vaccine or effective treatment. ASF is endemic in countries in sub-Saharan Africa, but since its introduction to the Caucasus region in 2007, a highly virulent strain of ASF virus (ASFV) has continued to circulate and spread into Eastern Europe and Russia, and most recently into Western Europe, China, and various countries of Southeast Asia.

Aujeszky's Disease and Hepatitis E Viruses Transmission between Domestic Pigs and Wild Boars in Corsica: Evaluating the Importance of Wild/Domestic Interactions and the Efficacy of Management Measures.

Wildlife species as reservoirs of infectious pathogens represent a serious constraint in the implementation of disease management strategies. In the Mediterranean island of Corsica, the dynamics of hepatitis E virus (HEV) and Aujeszky's disease virus (ADV) are suspected to be influenced by interactions between wild and domestic pigs. To improve our understanding of these influences, we first compared the seroprevalences of both viruses in domestic pig populations from different locations with contrasted levels of wild-domestic interactions, ADV vaccination, biosafety, and farm husbandry.

Dynamic changes in bronchoalveolar macrophages and cytokines during infection of pigs with a highly or low pathogenic genotype 1 PRRSV strain.

Porcine reproductive and respiratory syndrome virus (PRRSV) replicates primarily in pulmonary alveolar macrophages (PAMs) and the resulting lung damage is influenced by strain virulence. To better understand the pathogenesis of PRRSV infection, we performed a longitudinal study of the PAM population and lung cytokines in specific pathogen-free pigs infected either with the highly pathogenic Lena strain or with the low pathogenic Finistere strain in comparison to uninfected pigs. Bronchoalveolar lavage fluid (BALF) and blood were collected to follow viral, cellular and cytokine changes in lung with respect to clinical signs and systemic events.

Effect of O. porcinus Tick Salivary Gland Extract on the African Swine Fever Virus Infection in Domestic Pig.

African swine fever is a haemorrhagic disease in pig production that can have disastrous financial consequences for farming. No vaccines are currently available and animal slaughtering or area zoning to restrict risk-related movements are the only effective measures to prevent the spread of the disease. Ornithodoros soft ticks are known to transmit the African swine fever virus (ASFV) to pigs in farms, following the natural epidemiologic cycle of the virus.

How to survey classical swine fever in wild boar (Sus scrofa) after the completion of oral vaccination? Chasing away the ghost of infection at different spatial scales.

Oral mass vaccination (OMV) is considered as an efficient strategy for controlling classical swine fever (CSF) in wild boar. After the completion of vaccination, the presence of antibodies in 6-12 month-old hunted wild boars was expected to reflect a recent CSF circulation. Nevertheless, antibodies could also correspond to the long-lasting of maternal antibodies.

Evolution and molecular epidemiology of classical swine fever virus during a multi-annual outbreak amongst European wild boar.

Classical swine fever is a viral disease of pigs that carries tremendous socio-economic impact. In outbreak situations, genetic typing is carried out for the purpose of molecular epidemiology in both domestic pigs and wild boar. These analyses are usually based on harmonized partial sequences.