Title: Characterization of Senecavirus A Isolates Collected From the Environment of U.S. Sow Slaughter Plants

Abstract

Vesicular disease caused by Senecavirus A (SVA) is clinically indistinguishable from foot-and-mouth disease (FMD) and other vesicular diseases of swine. When a vesicle is observed in FMD-free countries, a costly and time-consuming foreign animal disease investigation (FADI) is performed to rule out FMD. Recently, there has been an increase in the number of FADIs and SVA positive samples at slaughter plants in the U.S. The objectives of this investigation were to: (1) describe the environmental burden of SVA in sow slaughter plants; (2) determine whether there was a correlation between PCR diagnostics, virus isolation (VI), and swine bioassay results; and (3) phylogenetically characterize the genetic diversity of contemporary SVA isolates. Environmental swabs were collected from three sow slaughter plants (Plants 1-3) and one market-weight slaughter plant (Plant 4) between June to December 2020. Of the 426 samples taken from Plants 1-3, 304 samples were PCR positive and 107 were VI positive. There was no detection of SVA by PCR or VI at Plant 4. SVA positive samples were most frequently found in the summer (78.3% June-September, vs. 59.4% October-December), with a peak at 85% in August. Eighteen PCR positive environmental samples with a range of C_t values were selected formore » a swine bioassay: a single sample infected piglets (n = 2). A random subset of the PCR positive samples was sequenced; and phylogenetic analysis demonstrated co-circulation and divergence of two genetically distinct groups of SVA. These data demonstrate that SVA was frequently found in the environment of sow slaughter plants, but environmental persistence and diagnostic detection was not indicative of whether a sampled was infectious to swine. Consequently, a more detailed understanding of the epidemiology of SVA and its environmental persistence in the marketing chain is necessary to reduce the number of FADIs and aide in the development of control measures to reduce the spread of SVA.« less

Authors:

Hoffman, Kyle S. ^[1]; Humphrey, Nicki L. ^[2]; Korslund, John A. ^[3]; Anderson, Tavis K. ^[1]; Faaberg, Kay. S. ^[1]; Lager, Kelly M. ^[1]; Buckley, Alexandra C. ^[1]

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+ Show Author Affiliations

1. US Dept. of Agriculture (USDA)., Ames, IA (United States). Agricultural Research Service (ARS)
2. USDA Forest Service, Fort Collins, CO (United States). Animal Plant Health Inspection Service
3. USDA Forest Service, Riverdale, MD (United States). Animal Plant Health Inspection Service

Publication Date:

Wed Jun 22 00:00:00 EDT 2022

Research Org.:

Oak Ridge Associated Universities (ORAU), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE; USDA

OSTI Identifier:

1983100

Grant/Contract Number:  

AC05-06OR23100

Resource Type:

Accepted Manuscript

Journal Name:

Frontiers in Veterinary Science

Additional Journal Information:

Journal Volume: 9; Journal ID: ISSN 2297-1769

Publisher:

Frontiers Media S.A.

Country of Publication:

United States

Language:

English

Subject:

59 BASIC BIOLOGICAL SCIENCES; Senecavirus A; genetic diversity; slaughter plants; bioassay; SVA; swine