Exclusion of Superinfection or Enhancement of Superinfection in Pestiviruses-APPV Infection Is Not Dependent on ADAM17.

Some viruses can suppress superinfections of their host cells by related or different virus species. The phenomenon of superinfection exclusion can be caused by inhibiting virus attachment, receptor binding and entry, by replication interference, or competition for host cell resources. Blocking attachment and entry not only prevents unproductive double infections but also stops newly produced virions from re-entering the cell post-exocytosis.

Essential role of -encoded mature NS3 in the genome packaging of classical swine fever virus.

Unlabelled: Classical swine fever virus (CSFV) is a member of the genus within the family . The enveloped particles contain a plus-stranded RNA genome encoding a single large polyprotein. The processing of this polyprotein undergoes dynamic changes throughout the infection cycle.

Modulation of ADAM17 Levels by Pestiviruses Is Species-Specific.

Upon host cell infection, viruses modulate their host cells to better suit their needs, including the downregulation of virus entry receptors. ADAM17, a cell surface sheddase, is an essential factor for infection of bovine cells with several pestiviruses. To assess the effect of pestivirus infection on ADAM17, the amounts of cellular ADAM17 and its presence at the cell surface were determined.

Characterization of a Molecular Clone of Deformed Wing Virus B.

Honey bees () play a crucial role in agriculture through their pollination activities. However, they have faced significant health challenges over the past decades that can limit colony performance and even lead to collapse. A primary culprit is the parasitic mite , known for transmitting harmful bee viruses.

Processing of the 3C/D Region of the Deformed Wing Virus (DWV).

The deformed wing virus (DWV) belongs to the genus and the family within the order . It is an important pathogen of the Western honey bee, , causing major losses among honey bee colonies in association with the ectoparasitic mite Although DWV is one of the best-studied insect viruses, the mechanisms of viral replication and polyprotein processing have been poorly studied in the past. We investigated the processing of the protease-polymerase region at the C-terminus of the polyprotein in more detail using recombinant expression, novel serological reagents, and virus clone mutagenesis.

Functional comparisons of the virus sensor RIG-I from humans, the microbat , and the megabat , and their response to SARS-CoV-2 infection.

A common hypothesis holds that bats (order ) are outstanding reservoirs for zoonotic viruses because of a special antiviral interferon (IFN) system. However, functional studies about key components of the bat IFN system are rare. RIG-I is a cellular sensor for viral RNA signatures that activates the antiviral signaling chain to induce IFN.

Crude Extracts of Strains (Ascomycota) Affect Honey Bee () Resistance to Chronic Bee Paralysis Virus.

Viruses contribute significantly to the global decline of honey bee populations. One way to limit the impact of such viruses is the introduction of natural antiviral compounds from fungi as a component of honey bee diets. Therefore, we examined the effect of crude organic extracts from seven strains of the fungal genus in honey bee diets under laboratory conditions.

A Conserved Stem-Loop Structure within ORF5 Is a Frequent Recombination Hotspot for Porcine Reproductive and Respiratory Syndrome Virus 1 (PRRSV-1) with a Particular Modified Live Virus (MLV) Strain.

The emergence of recombinant PRRSV strains has been observed for more than a decade. These recombinant viruses are characterized by a genome that contains genetic material from at least two different parental strains. Due to the advanced sequencing techniques and a growing number of data bank entries, the role of PRRSV recombinants has become increasingly important since they are sometimes associated with clinical outbreaks.

DNAJC14-Independent Replication of the Atypical Porcine Pestivirus.

Atypical porcine pestiviruses (APPV; ) are a recently discovered, very divergent species of the genus within the family . The presence of APPV in piglet-producing farms is associated with the occurrence of so-called "shaking piglets," suffering from mild to severe congenital tremor type A-II. Previous studies showed that the cellular protein DNAJC14 is an essential cofactor of the NS2 autoprotease of all classical pestiviruses.

New Emergence of the Novel Pestivirus Linda Virus in a Pig Farm in Carinthia, Austria.

Linda virus (LindaV) was first identified in a pig farm in Styria, Austria in 2015 and associated with congenital tremor (CT) type A-II in newborn piglets. Since then, only one more LindaV affected farm was retrospectively discovered 10 km away from the initially affected farm. Here, we report the recent outbreak of a novel LindaV strain in a farrow-to-finish farm in the federal state Carinthia, Austria.

Characterization of a Cytopathogenic Reporter CSFV.

Cytopathogenic (cp) pestiviruses frequently emerge in cattle that are persistently infected with the bovine viral diarrhea virus (BVDV) as a consequence of RNA recombination and mutation. They induce apoptosis in infected tissue cultures, are highly attenuated in the immunocompetent host, and unable to establish persistent infections after diaplacental infections. Cp strains of BVDV have been used as naturally attenuated live vaccines and for species-specific plaque reduction tests for the indirect serological detection of BVDV.

Emergence of a bufonid herpesvirus in a population of the common toad Bufo bufo in Germany.

Bufonid herpesvirus 1 (BfHV1) was initially described in 2014 from cases of mortalities and dermatitis in Swiss populations of the common toad Bufo bufo. We identified a closely related herpesvirus strain in a German common toad population affected by an ongoing epidemic of multifocal proliferative to ulcerative skin disease since 2018.

Prevalence of Linda Virus Neutralizing Antibodies in the Austrian Pig Population.

A novel pestivirus species, termed Lateral-shaking Inducing Neuro-Degenerative Agent virus (LindaV), was discovered in a piglet-producing farm in Austria in 2015 related to severe congenital tremor cases. Since the initial outbreak LindaV has not been found anywhere else. In this study, we determined the seroprevalence of LindaV infections in the domestic pig population of Austria.

Organization of the Structural Protein Region of La Jolla Virus Isolated from the Invasive Pest Insect .

(Ds) is an invasive pest insect that infests ripening fruit, causing severe economic losses. Control measures based on chemical pesticides are inefficient and undesirable, so biological alternatives have been considered, including native Ds viruses. We previously isolated a strain of La Jolla virus (LJV-Ds-OS20) from Ds in Germany as a candidate biopesticide.

Real Time Analysis of Bovine Viral Diarrhea Virus (BVDV) Infection and Its Dependence on Bovine CD46.

Virus attachment and entry is a complex interplay of viral and cellular interaction partners. Employing bovine viral diarrhea virus (BVDV) encoding an mCherry-E2 fusion protein (BVDV), being the first genetically labelled member of the family applicable for the analysis of virus particles, the early events of infection-attachment, particle surface transport, and endocytosis-were monitored to better understand the mechanisms underlying virus entry and their dependence on the virus receptor, bovine CD46. The analysis of 801 tracks on the surface of SK6 cells inducibly expressing fluorophore labelled bovine CD46 (CD46) demonstrated the presence of directed, diffusive, and confined motion.

A molecular clone of Chronic Bee Paralysis Virus (CBPV) causes mortality in honey bee pupae (Apis mellifera).

Among the many diseases compromising the well-being of the honey bee (Apis mellifera) the chronic paralysis syndrome of adult honey bees is one of the best described. The causative agent, chronic bee paralysis virus (CBPV), is a positive sense, single-stranded RNA virus with a segmented genome. Segment 1 encodes three putative open reading frames (ORFs), including the RNA-dependent RNA polymerase and other non-structural protein coding regions.

Clinical and Serological Evaluation of LINDA Virus Infections in Post-Weaning Piglets.

The novel pestivirus species known as lateral-shaking inducing neuro-degenerative agent (LINDA) virus emerged in 2015 in a piglet-producing farm in Austria. Affected piglets showed strong congenital tremor as a result of severe lesions in the central nervous system. Here, we report the results of a controlled animal infection experiment.

Fluorophore labelled BVDV: a novel tool for the analysis of infection dynamics.

Genetic labelling of viruses with a fluorophore allows to study their life cycle in real time, without the need for fixation or staining techniques. Within the family Flaviviridae, options for genetic labelling of non-structural proteins exist. Yet, no system to genetically label structural proteins has been put forward to date.

Design and evaluation of the immunogenicity and efficacy of a biomimetic particulate formulation of viral antigens.

Subunit viral vaccines are typically not as efficient as live attenuated or inactivated vaccines at inducing protective immune responses. This paper describes an alternative 'biomimetic' technology; whereby viral antigens were formulated around a polymeric shell in a rationally arranged fashion with a surface glycoprotein coated on to the surface and non-structural antigen and adjuvant encapsulated. We evaluated this model using BVDV E2 and NS3 proteins formulated in poly-(D, L-lactic-co-glycolic acid) (PLGA) nanoparticles adjuvanted with polyinosinic:polycytidylic acid (poly(I:C) as an adjuvant (Vaccine-NP).

Novel Pestivirus Species in Pigs, Austria, 2015.

A novel pestivirus species was discovered in a piglet-producing farm in Austria during virologic examinations of congenital tremor cases. The emergence of this novel pestivirus species, provisionally termed Linda virus, in domestic pigs may have implications for classical swine fever virus surveillance and porcine health management.

Emergence of a virulent porcine reproductive and respiratory syndrome virus (PRRSV) 1 strain in Lower Austria.

Background: In spring 2015, an outbreak of porcine reproductive and respiratory syndrome (PRRS) struck Lower Austria caused by a PRRS virus (PRRSV) strain spreading rapidly among both previously PRRSV negative and vaccinated pig herds. This case report describes the first well-documented emergence of the PRRSV strain responsible for this outbreak.

Case Presentation: A PRRSV seronegative piglet-producing farm in Lower Austria encountered losses in foetuses and suckling piglets of up to 90 %; clinical signs in sows and nursery piglets included fever and reduced feed intake.

The core protein of a pestivirus protects the incoming virus against IFN-induced effectors.

A multitude of viral factors - either inhibiting the induction of the IFN-system or its effectors - have been described to date. However, little is known about the role of structural components of the incoming virus particle in protecting against IFN-induced antiviral factors during or immediately after entry. In this study, we take advantage of the previously reported property of Classical swine fever virus (family Flaviviridae, genus Pestivirus) to tolerate a deletion of the core protein if a compensatory mutation is present in the NS3-helicase-domain (Vp447).

Congenital infection with atypical porcine pestivirus (APPV) is associated with disease and viral persistence.

In 2013, several Austrian piglet-producing farms recorded outbreaks of action-related repetitive myoclonia in newborn piglets ("shaking piglets"). Malnutrition was seen in numerous piglets as a complication of this tremor syndrome. Overall piglet mortality was increased and the number of weaned piglets per sow decreased by more than 10% due to this outbreak.

Construction and Rescue of a Molecular Clone of Deformed Wing Virus (DWV).

European honey bees are highly important in crop pollination, increasing the value of global agricultural production by billions of dollars. Current knowledge about virulence and pathogenicity of Deformed wing virus (DWV), a major factor in honey bee colony mortality, is limited. With this study, we close the gap between field research and laboratory investigations by establishing a complete in vitro model for DWV pathogenesis.

Influenza A Virus Infection in Pigs Attracts Multifunctional and Cross-Reactive T Cells to the Lung.

Unlabelled: Pigs are natural hosts for influenza A viruses and play a critical role in influenza epidemiology. However, little is known about their influenza-evoked T-cell response. We performed a thorough analysis of both the local and systemic T-cell response in influenza virus-infected pigs, addressing kinetics and phenotype as well as multifunctionality (gamma interferon [IFN-γ], tumor necrosis factor alpha [TNF-α], and interleukin-2 [IL-2]) and cross-reactivity.