Genome Sequences of Vesicular Stomatitis Indiana Viruses from the 2019 Outbreak in the Southwest United States

Genome sequence of a vesicular stomatitis Indiana virus isolate collected in 1988 from a naturally infected bovine in Mexico

We report the near-full genome sequence of a vesicular stomatitis Indiana virus (VSIV) originally collected from a naturally infected bovine in south-central Mexico. This sequence represents a coding-complete genome sequence of a VSIV from Mexico, a country where vesicular stomatitis is endemic.

Exploring the Molecular Basis of Vesicular Stomatitis Virus Pathogenesis in Swine: Insights from Expression Profiling of Primary Macrophages Infected with M51R Mutant Virus

Vesicular stomatitis virus (VSV) is an emergent virus affecting livestock in the US. Previously, using a recombinant VSV carrying the M51R mutation in the matrix protein (rNJ0612NME6-M51R), we evaluated the pathogenesis of this virus in pigs. Our results indicated that rNJ0612NME6-M51R represented an attenuated phenotype in in-vivo and in ex-vivo in pig macrophages, resembling certain clinical features observed in field VSV isolates. In order to gain more insight into the molecular basis leading to the attenuation of rNJ0612NME6-M51R in pigs, we conducted a microarray analysis to assess the gene expression profiles of primary porcine macrophages infected with rNJ0612NME6-M51R compared to its parental virus (rNJ0612NME6). Our results showed an overall higher gene expression in macrophages infected with rNJ0612NME6-M51R. Specifically, we observed that the pathways related with immune cytokine signaling and interferon (IFN)-related responses (including activation, signaling, induction, and antiviral mechanisms) were the ones comprising most of the relevant genes identified during this study. Collectively, the results presented herein highlight the relevance of type I interferon during the pathogenesis of VSV in pigs. The information generated from this study may represent a framework for future studies intended to understand the molecular bases of the pathogenesis of field strains in livestock.

A Multiplex Real-Time Reverse Transcription Polymerase Chain Reaction Assay With Enhanced Capacity to Detect Vesicular Stomatitis Viral Lineages of Central American Origin

Vesicular stomatitis virus (VSV) causes a disease in susceptible livestock that is clinically indistinguishable from foot-and-mouth disease. Rapid testing is therefore critical to identify VSV and rule out FMD. We previously developed and validated a multiplex real-time reverse transcription polymerase chain reaction assay (mRRT-PCR) for detection of both VS New Jersey virus (VSNJV) and VS Indiana virus (VSIV). However, it was subsequently apparent that this assay failed to detect some VSNJV isolates in Mexico, especially in genetic group II, lineage 2.1. In order to enhance the sensitivity of the mRRT-PCR for VSNJV, parts of the assay were redesigned and revalidated using new and improved PCR chemistries. The redesign markedly improved the assay by increasing the VSNJV detection sensitivity of lineage 2.1 and thereby allowing detection of all VSNJV clades. The new assay showed an increased capability to detect VSNJV. Specifically, the new mRRT-PCR detected VSNJV in 100% (87/87) of samples from Mexico in 2006-2007 compared to 74% for the previous mRRT-PCR. Furthermore, the analytical sensitivity of the new mRRT-PCR was enhanced for VSNJV. Importantly, the modified assay had the same sensitivity and specificity for VSIV as the previously published assay. Our results highlight the challenges the large genetic variability of VSV pose for virus detection by mRRT-PCR and show the importance of frequent re-evaluation and validation of diagnostic assays for VSV to ensure high sensitivity and specificity.

Surveillance along the Rio Grande during the 2020 Vesicular Stomatitis Outbreak Reveals Spatio-Temporal Dynamics of and Viral RNA Detection in Black Flies

Vesicular stomatitis virus (VSV) emerges periodically from its focus of endemic transmission in southern Mexico to cause epizootics in livestock in the US. The ecology of VSV involves a diverse, but largely undefined, repertoire of potential reservoir hosts and invertebrate vectors. As part of a larger program to decipher VSV transmission, we conducted a study of the spatiotemporal dynamics of Simulium black flies, a known vector of VSV, along the Rio Grande in southern New Mexico, USA from March to December 2020. Serendipitously, the index case of VSV-Indiana (VSIV) in the USA in 2020 occurred at a central point of our study. Black flies appeared soon after the release of the Rio Grande’s water from an upstream dam in March 2020. Two-month and one-year lagged precipitation, maximum temperature, and vegetation greenness, measured as Normalized Difference Vegetation Index (NDVI), were associated with increased black fly abundance. We detected VSIV RNA in 11 pools comprising five black fly species using rRT-PCR; five pools yielded a VSIV sequence. To our knowledge, this is the first detection of VSV in the western US from vectors that were not collected on premises with infected domestic animals.

Near-Complete Genome Sequences of Vesicular Stomatitis Virus Isolates from the 2020 Outbreak in Kansas

Here, we report the near-complete genome sequences of vesicular stomatitis virus (VSV) serotype Indiana isolates from the 2020 U.S. outbreak. The sequences were obtained from swabs collected from Kansas horses in July and August. The four genome sequences help improve our understanding of VSV outbreak dynamics in the United States.

Here, we report the near-complete genome sequences of vesicular stomatitis virus (VSV) serotype Indiana isolates from the 2020 U.S. outbreak. The sequences were obtained from swabs collected from Kansas horses in July and August. The four genome sequences help improve our understanding of VSV outbreak dynamics in the United States.