Serological Responses of Raccoons and Striped Skunks to Ontario Rabies Vaccine Bait in West Virginia during 2012–2016

Authors

Shylo R. Johnson, USDA APHIS Wildlife ServicesFollow
Dennis Slate, USDA APHIS Wildlife ServicesFollow
Kathleen M. Nelson, USDA National Rabies Management ProgramFollow
Amy J. Davis, USDA NationalWildlife Research Center,Follow
Samual A. Mills, USDA APHIS Wildlife ServicesFollow
John T. Forbes, USDA APHIS Wildlife ServicesFollow
Kurt VerCauteren, USDA APHIS Wildlife ServicesFollow
Amy T. Gilbert, USDA National Wildlife Research CenterFollow
Richard B. Chipman, USDA National Rabies Management ProgramFollow

ORCID IDs

Amy J. Davis https://orcid.org/0000-0002-4962-9753

Amy T. Gilbert https://orcid.org/0000-0002-8256-0081

Document Type

Article

Date of this Version

2021

Citation

Johnson, S.R.; Slate, D.; Nelson, K.M.; Davis, A.J.; Mills, S.A.; Forbes, J.T.; VerCauteren, K.C.; Gilbert, A.T.; Chipman, R.B. Serological Responses of Raccoons and Striped Skunks to Ontario Rabies Vaccine Bait inWest Virginia during 2012–2016. Viruses 2021, 13, 157. https://doi.org/10.3390/v13020157

Comments

Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license

Abstract

Since the 1990s, oral rabies vaccination (ORV) has been used successfully to halt the westward spread of the raccoon rabies virus (RV) variant from the eastern continental USA. Elimination of raccoon RV from the eastern USA has proven challenging across targeted raccoon (Procyon lotor) and striped skunk (Mephitis mephitis) populations impacted by raccoon RV. Field trial evaluations of the Ontario Rabies Vaccine Bait (ONRAB) were initiated to expand ORV products available to meet the rabies management goal of raccoon RV elimination. This study describes the continuation of a 2011 trial inWest Virginia. Our objective was to evaluate raccoon and skunk response to ORV occurring in West Virginia for an additional two years (2012–2013) at 75 baits/km2 followed by three years (2014–2016) of evaluation at 300 baits/km2. We measured the change in rabies virus-neutralizing antibody (RVNA) seroprevalence in targeted wildlife populations by comparing levels pre- and post-ORV during each year of study. The increase in bait density from 75/km2 to 300/km2 corresponded to an increase in average post-ORV seroprevalence for raccoon and skunk populations. Raccoon population RVNA levels increased from 53% (300/565, 95% CI: 50–57%) to 82.0% (596/727, 95% CI: 79–85%) during this study, and skunk population RVNA levels increased from 11% (8/72, 95% CI: 6–20%) to 39% (51/130, 95% CI: 31–48%). The RVNA seroprevalence pre-ORV demonstrated an increasing trend across study years for both bait densities and species, indicating that multiple years of ORV may be necessary to achieve and maintain RVNA seroprevalence in target wildlife populations for the control and elimination of raccoon RV in the eastern USA.