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

Katherine I Young; Federico Valdez; Christina Vaquera; Carlos Campos; Lawrence Zhou; Helen K Vessels; J Kevin Moulton; Barbara S Drolet; Paula Rozo-Lopez; Angela M Pelzel-McCluskey; Debra C Peters; Luis L Rodriguez; Kathryn A Hanley

doi:10.3390/pathogens10101264

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

Pathogens. 2021 Oct 1;10(10):1264. doi: 10.3390/pathogens10101264.

Authors

Affiliations

¹ Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA.
² Jornada Experimental Range Unit, Agricultural Research Service, US Department of Agriculture, Las Cruces, NM 88003, USA.
³ Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Greenport, NY 11944, USA.
⁴ The Arthropod Collection, Department of Entomology, Plant Pathology, and Weed Science, New Mexico State University, Las Cruces, NM 88003, USA.
⁵ Department of Entomology and Plant Pathology, Institute of Agriculture, University of Tennessee, Knoxville, TN 37996, USA.
⁶ Arthropod-Borne Animal Diseases Research Unit, Center for Grain and Animal Health Research, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA.
⁷ Department of Entomology, Kansas State University, Manhattan, KS 66506, USA.
⁸ Surveillance, Preparedness and Response Service, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO 80526, USA.

Abstract

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.

Keywords: New Mexico; Simuliidae; arbovirus; rhabdovirus; river; vector; vesicular stomatitis virus.