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Viruses 14(2), 381 (2022). doi:10.3390/v14020381 special issue: "Veterinary Infectious Diseases / Topic Editors: Dr. Chao-Nan Lin, Dr. Peck Toung Ooi", Published by MDPI, Basel

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. No connection between this farm and the previously affected farms could be discovered. The outbreak was characterized by severe CT cases in several litters and high preweaning mortality. A herd visit two months after the onset of clinical symptoms followed by a diagnostic workup revealed the presence of several viremic six-week-old nursery pigs. These animals shed large amounts of virus via feces and saliva, implying an important epidemiological role for within- and between-herd virus transmission. The novel LindaV strain was isolated and genetically characterized. The findings underline a low prevalence of LindaV in the Austrian pig population and highlight the threat when introduced into a pig herd. Furthermore, the results urge the need to better understand the routes of persistence and transmission of this enigmatic pestivirus in the pig population.

This thesis examines climate communication and its challenges from a systemic perspective. The idea is to take a systems approach to understand, critique, and reframe current narratives within our systems. It emphasizes that the scientific evidence on climate change is challenging and demands action from society. However, climate communication shows not only to be about mitigating climate change, but also about comprehensive implementation of sustainability. The work builds onthe idea that systemic structures of society are formative for narratives of communication and therefore need to be critically examined. The thesis further aims to provide insights into new narratives of climate communication. It is argued that by overcoming problems in current systems,contributions can be made to promote climate action. Climate communication in this sense needs future-oriented considerations for the actual implementation of social change.The systematic approach can generally be considered a highly relevant for scientific examinations.Especially for complex issues like climate change, which include both environmental and social aspects, a holistic approach is necessary. This can best be achieved by taking a systemic perspective, which assumes that all things are interconnected. Ultimately, systemic societalstructures in the political, economic and individual spheres must intervene and implement sustainability as much as possible. Only through a fundamental critical engagement with systemsissues can the interactions of earth and social systems be understood and solutions for positive change developed.Lastly, also narratives can take the holistic perspective and initiate change by intregating progressive approaches. At its core, the goal of climate communication is not just to bring scientific knowledge to the masses and generate understanding, but rather to foster storytelling that promotes a more equitable society based on values such as cooperation, well-being, and resilience. In this sense, climate communication is about much more than saving the planet. It is about developing a narrative that promotes hope for societal improvement on multiple levels.

Prevalence studies have demonstrated a global distribution of equine hepacivirus (EqHV), a member of the family Flaviviridae. However, apart from a single case of vertical transmission, natural routes of EqHV transmission remain elusive. Many known flaviviruses are horizontally transmitted between hematophagous arthropods and vertebrate hosts. This study represents the first investigation of potential EqHV transmission by mosquitoes. More than 5000 mosquitoes were collected across Austria and analyzed for EqHV ribonucleic acid (RNA) by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Concurrently, 386 serum samples from horses in eastern Austria were analyzed for EqHV-specific antibodies by luciferase immunoprecipitation system (LIPS) and for EqHV RNA by RT-qPCR. Additionally, liver-specific biochemistry parameters were compared between EqHV RNA-positive horses and EqHV RNA-negative horses. Phylogenetic analysis was conducted in comparison to previously published sequences from various origins. No EqHV RNA was detected in mosquito pools. Serum samples yielded an EqHV antibody prevalence of 45.9% (177/386) and RNA prevalence of 4.15% (16/386). EqHV RNA-positive horses had significantly higher glutamate dehydrogenase (GLDH) levels (p = 0.013) than control horses. Phylogenetic analysis showed high similarity between nucleotide sequences of EqHV in Austrian horses and EqHV circulating in other regions. Despite frequently detected evidence of EqHV infection in Austrian horses, no viral RNA was found in mosquitoes. It is therefore unlikely that mosquitoes are vectors of this flavivirus.

Diplomarbeit - Veterinärmedizinische Universität Wien - 2021, Ziel dieser Diplomarbeit war es herauszufinden, ob sich der Einsatz von Processing Fluids für ein PRRS-Betriebsmonitoring nach akutem PRRS Ausbruch eignet. Im Zuge eines PRRS-Ausbruchs bei einem niederösterreichischen Ferkelproduzenten mit rund 150 Zuchtsauen wurden über einen Zeitraum von 12 Monaten 182 Processing Fluid Proben gesammelt und mittels RT – PCR ORF7 sowie der RT – qPCR ORF1 analysiert, untereinander und mit vorhandenen Serumproben verglichen. Eine Sequenzierung des Genoms fand insgesamt bei 13 Proben im ORF5 und ORF7 statt, welche belegte, dass das im Bereich ORF5 bzw. ORF7 unveränderte Virus über mehrere Monate im Betrieb zirkulierte. Zusätzlich wurden Standardkurven für die neue PRRSV ORF1 RT-qPCR erstellt, um die Viruskonzentrationen der Processing Fluid Proben bestimmen zu können. Interessant war, dass sich die Viruslast von Gruppe 1 zu Gruppe 2 deutlich reduzierte und bei letzterer knapp am definierten Detektionslimit lag. Die PRRS-Virus Nachweisgrenze für die RT – qPCR ORF1 in den Processing Fluids lag bei 1*10^4 genomischen Einheiten pro Milliliter Processing Fluid, welche aufgrund der ermittelten Ergebnisse sensitiver als die RT – PCR ORF7 zu werten ist. Mithilfe der ORF-1 RT – qPCR konnten zwei weitere Processing Fluids positiv auf das PRRS-Virus getestet werden, welche unter der ORF 7 RT – PCR negativ zu werten waren. Ein vermehrtes Auftreten PRRSV positiver Ferkel bei Jungsauen (36%) im Vergleich zu Altsauen (20,35%) konnte in Zuge dieser Diplomarbeit aufgrund der zeitnah erfolgten Impfung und unzureichender Verteilung von Jung- und Altsauen nicht belegt werden. Jedoch konnte dank zahlreicher Faktoren wie dem zeitnahen Einsatz einer MLV-Vakzines, konsequentem Rein-Raus, dem geschlossenen System ohne Zukäufe etc. eine kurze „time to baseline production“ von etwa 12 Wochen erreicht werden. Interessant wäre zu wissen, ob und wie sich Processing Fluids poolen lassen und wie verlässlich deren Ergebnisse sind., The aim of this diploma thesis was to find out whether the use of processing fluids is suitable for PRRS farm monitoring after an acute PRRS outbreak. In the course of a PRRS outbreak in a piglet producing farm in Lower Austria with about 150 breeding sows, 182 processing fluid samples were collected over a period of 12 months and analyzed by ß-actin-ORF1 multiplex PCR, ORF 7 RT - PCR and ORF 1 RT - qPCR, and compared with each other as well as with serum samples. Genome sequencing was performed on 13 samples in ORF5 and ORF7 which proved that the virus did not change in ORF5 or ORF7 during circulation in the farm for several months. In addition, standard curves for the new ORF 1 RT-qPCR were generated to determine the virus concentrations of the processing fluid samples. It was interesting to note that the viral load decreased significantly from group 1 to group 2 just above the defined detection limit. The PRRS virus detection limit for ORF 1 RT - qPCR in processing fluids was 1*10^4 genomic units per milliliter of processing fluid which is more sensitive than the common ORF 7 RT - PCR. Using RT - qPCR ORF1, two additional processing fluids tested positive for PRRS virus which were negative using ORF 7 RT - PCR. An increased occurrence of PRRSV positive piglets in gilts (36%) compared to older sows (20,35%) could not be proven during this thesis due to the timely vaccination and insufficient distribution of young and older sows. However, thanks to numerous factors such as the timely use of an MLV vaccine, consistent clean-out, the closed system without additional purchases, etc., a short "time to baseline production" of about 12 weeks could be achieved. It would be interesting to know if and how processing fluids can be pooled and how reliable their results are.