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Background: In recent years, the wildlife/livestock interface has attracted increased attention due to disease transmission between wild and domestic animal populations. The ongoing spread of African swine fever (ASF) in European wild boar (Sus scrofa) emphasize the need for further understanding of the wildlife/livestock interface to prevent disease spill-over between the wild and domestic populations. Although wild boar may also act as a potential source for other infectious disease agents, ASF is currently the most severe threat from wild boar to domestic pigs. To gather information on the wild boar situation at commercial pig producing farms in Sweden, a digital questionnaire survey was distributed through the animal health services. Results: Most pigs produced for commercial purposes in Sweden are raised without outdoor access. Of the 211 responding pig producers, 80% saw wild boar or signs of wild boar activity in the vicinity of their farm at least once during the year. Observations were significantly correlated with geographical region, but there was no correlation between farm characteristics (farm size, main type of production, outdoor access) and observed wild boar presence or proximity. However, a reported higher frequency of wild boar observations was positively correlated with the observations being made in closer proximity to the farm. Hunting and strategic baiting were the most common mitigation strategies used to keep wild boar at bay. Of the 14 farms raising pigs with outdoor access, 12 responded that these pigs could be raised solely indoors if needed. Pigs with outdoor access are required to be fenced in, but double fencing in these outdoor pig enclosures was not practiced by all. A perimeter fence surrounding any type of pig farm was very rare. More than half of the producers that grew crops with intended use for pigs reported crop damage by wild boar. Conclusion: This study shows that although pigs raised for commercial purposes in Sweden are, to a large extent, kept indoors the potential for indirect contact with wild boar exists and must be considered. Variable local situations regarding wild boar abundance may require an adaptive approach regarding biosecurity efforts. [ABSTRACT FROM AUTHOR]

We found highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b associated with meningoencephalitis in a stranded harbor porpoise (Phocoena phocoena). The virus was closely related to strains responsible for a concurrent avian influenza outbreak in wild birds. This case highlights the potential risk for virus spillover to mammalian hosts. [ABSTRACT FROM AUTHOR]

In contrast to sparse historical observational records, five Sowerby's beaked whales (SBW) stranded and died in Swedish waters between 2015 and 2020. Here we summarize historical records of SBWs in the Skagerrak basin and adjacent waters. The three recent stranding events from Sweden are described, and the post-mortem findings, including diet analysis, from the five SBWs are presented. Of 30 historical records of SBWs observations since 1869, 13 (43%) were documented between 2010 and 2021, and records between July and November were the most frequent. The recent stranding events occurred in October 2015 (n = 1), August 2019 (n = 3) and July 2020 (n = 1). Four of the SBWs were examined through necropsy, and one was sampled in the field. They were all sub-adults and included a single female and four males. The causes of death were emaciation, euthanasia due to traumatic injury, and live stranding of undetermined cause. Two SBWs each had a focal bone lesion consistent with osteomyelitis. Other findings included pox-like dermatitis, trauma, focal granulomas in a lymph node and intestine, and ulceration of the stomach. CT scans were performed on the heads of two animals, with inconclusive results. Three SBWs had hard parts in the gastrointestinal tract that mainly consisted of otoliths from several fish species. An eDNA-analysis confirmed and supplemented the diet analysis, revealing 17 fish species in total, including species not previously described as prey for SBW, such as Pleuronectidae spp. The apparent increase in observational records since 2010 may indicate a shift in SBW distribution or changing threats to these animals. Our results support and expand theories on SBW movements and provide data on the biology and health of this poorly known species, which are valuable for conservation and legislation efforts. [ABSTRACT FROM AUTHOR]

Recombination is one of the major sources of genetic variation in viruses. RNA viruses, such as rabbit hemorrhagic disease virus (RHDV), are among the viruses with the highest recombination rates. Several recombination events have been described for RHDV, mostly as a consequence of their genomic architecture. Here, we undertook phylogenetic and recombination analyses of French and Swedish RHDV strains from 1994 to 2016 and uncovered a new intergenotypic recombination event. This event occurred in the late 1990s/early 2000s and involved nonpathogenic GI.3 strains as donors for the nonstructural part of the genome of these recombinants, while pathogenic GI.1d strains contributed to the structural part. These GI.3P–GI.1d recombinant strains did not entirely replace GI.1d (nonrecombinant) strains, but became the dominant strains in France and Sweden, likely due to a fitness advantage associated with this genomic architecture. GI.3P–GI.1d (P stands for polymerase) strains persisted until 2013 and 2016 in Sweden and France, respectively, and cocirculated with the new genotype GI.2 in France. Since strains from the first GI.2 outbreaks were GI.3P–GI.2, we hypothesize that GI.3P–GI.1d could be the parental strain. Our results confirm the outstanding recombination ability of RHDV and its importance in the evolution of lagoviruses, which was only revealed by studying complete genomic sequences. [ABSTRACT FROM AUTHOR]

Forty-one outbreaks of mortality in wild finches were reported in southern Norway, Sweden, and Finland in the second half of 2008 (n = 40) and in February 2009 (n = 1). Greenfinches (Carduelis chloris) and occasional chaffinches (Fringilla coelebs) primarily were affected. Forty-eight greenfinches, eight chaffinches, one hawfinch (Coccothraustes coccothraustes), and one blue tit (Parus caeruleus) from 22 incidents were examined postmortem. Birds were in poor nutritional condition and had necrotizing ingluvitis, esophagitis, and/or oropharyngitis. Viable trichomonads with morphology consistent with Trichomonas gallinae were demonstrated successfully in 65% and 71% of fresh carcasses examined by culture and wet mount, respectively. No primary bacterial pathogens were detected. To our knowledge, this is the first report of epizootic trichomoniasis in wild finches in Europe outside of the UK.