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The first case of pandemic H1N1 influenza (pH1N1) virus in feral swine in the United States was identified in Texas through the United States Department of Agriculture (USDA) Wildlife Services' surveillance program. Two samples were identified as pandemic influenza by reverse transcriptase quantitative PCR (RT-qPCR). Full-genome Sanger sequencing of all eight influenza segments was performed. In addition, Illumina deep sequencing of the original diagnostic samples and their respective virus isolation cultures were performed to assess the feasibility of using an unbiased whole-genome linear target amplification method and multiple sample sequencing in a single Illumina GAIIx lane. Identical sequences were obtained using both techniques. Phylogenetic analysis indicated that all gene segments belonged to the pH1N1 (2009) lineage. In conclusion, we have identified the first pH1N1 isolate in feral swine in the United States and have demonstrated the use of an easy unbiased linear amplification method for deep sequencing of multiple samples. [ABSTRACT FROM AUTHOR]

Graft-versus-host disease (GVHD) remains among the major causes of treatment failure in patients with multiple myeloma (MM) undergoing allogeneic hematopoietic cell transplantation (allo-HCT). The use of post-transplantation cyclophosphamide (PT-Cy) is now a well-established and widely used method for GVHD prophylaxis after HLA haploidentical HCT. However, the rationale for using PT-Cy in the setting of matched donor transplantation is less apparent, given the lesser degree of bidirectional alloreactivity. In this retrospective study, we investigated the role of PT-Cy as GVHD prophylaxis in patients with multiple myeloma underoing allo-HCT, among different donor types, to determine cumulative incidence of acute and chronic GVHD and impact on engraftment, progression-free survival (PFS), GVHD-free/relapse- free survival (GRFS), overall survival (OS), and NRM A total of 295 patients with MM underwent allo-HCT using grafts from a matched related donor (MRD; n = 67), matched unrelated donor (MUD; n = 72), mismatched related or unrelated donor (MMRD/MMUD, 1 antigen; n = 27), or haploidentical donor (haplo; n = 129) using PT-Cy between 2012 and 2018. In addition to PT-Cy, agents used in GVHD prophylaxis included calcineurin inhibitors in 239 patients (81%), with mycophenolate mofetil in 184 of those 239 (77%). For grade II-IV acute GVHD, the cumulative incidence at day +100 was 30% (95% confidence interval [CI], 25% to 36%), 9% (95% CI, 5% to 12%) for grade III-IV acute GVHD, and 27% (95% CI, 21% to 32%) for chronic GVHD (limited, 21%; extensive, 6%), with no differences by donor type. The median time to neutrophil engraftment was 19d (95% CI, 18-19), with no significant difference by donor type. The median time to platelet engraftment was delayed in haploidentical donor graft recipients (27 days versus 21 days; P < .001). Two-year OS, PFS, GRFS, and NRM were 51% (95% CI, 45% to 58%), 26% (95% CI, 20% to 32%), 24% (95% CI, 18% to 30%), and 19% (95% CI, 14% to 24%), respectively, with no significant difference between different donor types. In multivariable analyses, compared with the haplo donors, the use of MRDs was associated with significantly better OS (hazard ratio [HR], 0.6; 95% CI, 0.38 to 0.95; P = .029), and the use of MUDs was associated with a significantly higher GRFS (HR, 0.63; 95% CI, 0.42 to 0.97; P = .034). There was a trend toward improved PFS with use of MUDs (HR, 0.69; 95% CI, 0.46 to 1.04; P = .08). Our data show that PT-Cy in MM patients undergoing allo-HCT resulted in low rates of acute and chronic GVHD and led to favorable survival, especially in the matched related donor setting. © 2021 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc., (Copyright © 2021 The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Senecavirus A (SVA) is an emerging picornavirus that causes vesicular disease (VD) in swine. The virus has been circulating in swine in the United Stated (USA) since at least 1988, however, since 2014 a marked increase in the number of SVA outbreaks has been observed in swine worldwide. The factors that led to the emergence of SVA remain unknown. Evolutionary changes that accumulated in the SVA genome over the years may have contributed to the recent increase in disease incidence. Here we compared full-genome sequences of historical SVA strains (identified before 2010) from the USA and global contemporary SVA strains (identified after 2011). The results from the genetic analysis revealed 6.32 % genetic divergence between historical and contemporary SVA isolates. Selection pressure analysis revealed that the SVA polyprotein is undergoing selection, with four amino acid (aa) residues located in the VP1 (aa 735), 2A (aa 941), 3C (aa 1547) and 3D (aa 1850) coding regions being under positive/diversifying selection. Several aa substitutions were observed in the structural proteins (VP1, VP2 and VP3) of contemporary SVA isolates when compared to historical SVA strains. Some of these aa substitutions led to changes in the surface electrostatic potential of the structural proteins. This work provides important insights into the molecular evolution and epidemiology of SVA.

To understand the evolution of swine-origin H3N2v influenza viruses that have infected 320 humans in the USA since August 2011, we performed a phylogenetic analysis at a whole genome scale of North American swine influenza viruses (n = 200). All viral isolates evolved from the prototypical North American H3 cluster 4 (c4), with evidence for further diversification into subclusters. At least ten distinct reassorted H3N2/pandemic H1N1 (rH3N2p) genotypes were identified in swine. Genotype 1 (G1) was most frequently detected in swine and all human H3N2v viruses clustered within a single G1 clade. These data suggest that the genetic requirements for transmission to humans may be restricted to a specific subset of swine viruses. Mutations at putative antigenic sites as well as reduced serological cross-reactivity among the H3 subclusters suggest antigenic drift of these contemporary viruses.