Date of this Version
Journal of Wildlife Diseases, 50(3), 2014, pp. 582–595
In 2011, we conducted a field trial in rural West Virginia, USA to evaluate the safety and immunogenicity of a live, recombinant human adenovirus (AdRG1.3) rabies virus glycoprotein vaccine (Ontario Rabies Vaccine Bait; ONRAB) in wild raccoons (Procyon lotor) and striped skunks (Mephitis mephitis). We selected ONRAB for evaluation because of its effectiveness in raccoon rabies management in Ontario and Quebec, Canada, and significantly higher antibody prevalence rates in raccoons compared with a recombinant vaccinia-rabies glycoprotein (V-RG) vaccine, Raboral V-RGH, in US–Canada border studies. Raccoon rabies was enzootic and oral rabies vaccination (ORV) had never been used in the study area. We distributed 79,027 ONRAB baits at 75 baits/km2 mostly by fixed-wing aircraft along parallel flight lines at 750-m intervals. Antibody prevalence was significantly higher at 49.2% (n5262) in raccoons after ONRAB was distributed than the 9.6% (n5395) before ORV. This was the highest antibody prevalence observed in raccoons by US Department of Agriculture Wildlife Services for areas with similar management histories evaluated before and after an initial ORV campaign at 75 baits/km2 with Raboral V-RG. Tetracycline biomarker (TTCC) was significantly higher among antibody positive raccoons after ONRAB baiting and was similar among raccoons before ORV had been conducted, an indication of vaccine-induced rabies virus–neutralizing antibody production following consumption of bait containing TTCC. Skunk sample size was inadequate to assess ONRAB effects. Safety and immunogenicity results supported replication of this field trial and led to a recommendation for expanded field trials in 2012 to evaluate safety and immunogenicity of ground-distributed ONRAB at 150 baits/km2 in residential and commercial habitats in Ohio, USA and aerially distributed ONRAB at 75 baits/km2 in rural habitats along US–Quebec border.