Reovirus infections in turkeys are associated with arthritis and lameness. Viral genome sequence data are scarce, which makes an accurate description of the viral evolution and epidemiology difficult. In this study, we isolated and characterized turkey reoviruses from Hungary. The isolates were identified in 2016; these isolates were compared with earlier Hungarian turkey reovirus strains and turkey reoviruses isolated in the 2010s in the United States. Gene-wise sequence and phylogenetic analyses identified the cell-receptor binding protein and the main neutralization antigen, σC, to be the most conserved. The most genetically diverse gene was another surface antigen coding gene, μB. This gene was shown to undergo frequent reassortment among chicken and turkey origin reoviruses. Additional reassortment events were found primarily within members of the homologous turkey reovirus clade. Our data showed evidence for low variability among strains isolated from independent outbreaks, a finding that suggests a common source of turkey reoviruses in Hungarian turkey flocks. Given that commercial vaccines are not available, identification of the source of these founder virus strains would permit a more efficient prevention of disease outbreaks before young birds are settled to fattening facilities.
The phylogenetic relationships of glycopeptide resistance proteins were investigated. The amino acid sequences of vanA, vanB, vanR and vanS were used as queries to search against bacterial genomes in the NCBI RefSeq database. Hits with >60% amino acid identity and >90% query coverage were aligned, and phylogenetic trees were reconstructed. The ligase gene phylogenies were highly similar for both queries, revealing two major clusters. One contained [[vanA:vanM][vanB:vanD]vanF] and related proteins, with proteins from different Bacillaceae, mostly from Paenibacillus spp., in basal positions to all, except vanB. Ligases from streptomycetes formed the other cluster. The relative positions of vanH and vanX differed from those of the associated ligases, but the basal position of the Paenibacillus spp. and the separation of proteins of Streptomyces origin were similar. The accessory genes vanW, vanY and vanZ were associated with vanB, vanA/vanM and vanA, respectively; the basal branches were always proteins from different Bacillaceae but never from streptomycetes. Multiple homologs of the regulatory genes vanR and vanS were found in the genomes; those associated with the different ligases were unique to the ligases. Similarly to the accessory genes, vanRS from Bacillales and Clostridia, but never from streptomycetes, was found in the basal positions. In conclusion, the core genes vanA/B/D/F/M, vanH and vanX originate most probably from glycopeptide-producing streptomycetes, with Paenibacillus spp. (or other Bacillaceae) mediating the transfer, while the accessory genes and the regulatory apparatus probably originate from these Bacillaceae.
Porcine reproductive and respiratory syndrome virus (PRRSV) is a major concern worldwide. Control of PRRSV is a challenging task due to various factors, including the viral diversity and variability. In this study, we evaluated an amplicon library preparation protocol targeting the ORF7 region of both PRRSV species, Betaarterivirus suid 1 and Betaarterivirus suid 2. We designed tailed primers for a two-step PCR procedure that generates ORF7-specific amplicon libraries suitable for use on Illumina sequencers. We tested the method with serum samples containing common laboratory strains and with pooled serum samples (n = 15) collected from different pig farms during 2019–2021 in Hungary. Testing spiked serum samples showed that the newly designed method is highly sensitive and detects the viral RNA even at low copy numbers (corresponding to approx. Ct 35). The ORF7 sequences were easily assembled even from clinical samples. Two different sequence variants were identified in five samples, and the Porcilis MLV vaccine strain was identified as the minor variant in four samples. An in-depth analysis of the deep sequencing results revealed numerous polymorphic sites along the ORF7 gene in a total of eight samples, and some sites (positions 12, 165, 219, 225, 315, 345, and 351) were found to be common in several clinical specimens. We conclude that amplicon deep sequencing of a highly conserved region of the PRRSV genome could support both laboratory diagnosis and epidemiologic surveillance of the disease.
A panel of intestinal samples collected from common pheasants (Phasianus colchicus) between 2008 and 2017 was used for metagenomic investigation using an unbiased enrichment protocol and different bioinformatic pipelines. The number of sequence reads in the metagenomic analysis ranged from 1,419,265 to 17,507,704 with a viral sequence read rate ranging from 0.01% to 59%. When considering the sequence reads of eukaryotic viruses, RNA and DNA viruses were identified in the samples, including but not limited to coronaviruses, reoviruses, parvoviruses, and CRESS DNA viruses (i.e., circular Rep-encoding single-stranded DNA viruses). Partial or nearly complete genome sequences were reconstructed of at least three different parvoviruses (dependoparvovirus, aveparvovirus and chaphamaparvovirus), as well as gyroviruses and diverse CRESS DNA viruses. Generating information of virus diversity will serve as a basis for developing specific diagnostic tools and for structured epidemiological investigations, useful to assess the impact of these novel viruses on animal health.
Prototheca infections are rare in cats, and they are usually associated with cutaneous or subcutaneous infections by P. wickerhamii, with no evidence of neurological signs or systemic disease. In this study, we report the identification of prototheca in the cerebrospinal fluid (CSF) of a cat with neurological symptoms. Fourteen CSF samples were gathered from cats presented with neurological disease between 2012 and 2014. The inclusion criteria for the samples were an increase in CSF protein and cell number (pleocytosis), suggestive of an infectious inflammatory status of the central nervous system (CNS). Nine samples fulfilled the inclusion criteria (inflammatory samples), while five samples, used as control, did not (non-inflammatory samples). All the samples were screened molecularly for different pathogens associated with CNS disease in cats, including prototheca. Out of 14 CSF samples, only one inflammatory sample tested positive for prototheca. Upon sequence and phylogenetic analysis of the amplicon, the strain was characterized as P. bovis. This report is the first documented evidence of prototheca in the cerebrospinal fluid of a cat with neurological signs. Prototheca should be considered in the diagnostics procedures on the CNS of cats presented with infectious diseases.
Porcine reproductive and respiratory syndrome (PRRS) is the cause of the most severe economic losses in the pig industry worldwide. PRRSV is extremely diverse in Europe, which poses a significant challenge to disease control within a country or any region. With the combination of phylogenetic reconstruction and network analysis, we aimed to uncover the major routes of the dispersal of PRRSV clades within Hungary. In brief, by analyzing >2600 ORF5 sequences, we identified at least 12 clades (including 6 clades within lineage 1 and 3 clades within lineage 3) common in parts of Western Europe (including Denmark, Germany and the Netherlands) and identified 2 novel clades (designated X1 and X2). Of interest, some genetic clades unique to other central European countries, such as the Czech Republic and Poland, were not identified. The pattern of PRRSV clade distribution is consistent with the route of the pig trade among countries, showing that most of the identified clades were introduced from Western Europe when fatteners were transported to Hungary. As a result of rigorous implementation of the national eradication program, the swine population was declared officially free from PRRSV. This map of viral diversity and clade distribution will serve as valuable baseline information for the maintenance of PRRSV-free status in the post-eradication era.