A Test Case for Raccoon Roundworm Anthelmintic Baiting in Western Virginia

As a test case to determine the efficacy of anthelmintic baiting to reduce raccoon roundworm (Baylisascaris procyonis) prevalence in western Virginia, we deployed baits in a mountainous area of Roanoke Co., Virginia that historically was occupied by Allegheny woodrats (Neotoma magister). We deployed anthelmintic baits at 6-wk intervals from August to December 2024 at a density of 100/km2. We opportunistically collected raccoon (Procyon lotor) scat in the drop area from August 2024 to May 2025 and found a marked decline in prevalence of raccoon roundworm in the samples. Deeming this a measured success, we plan to deploy anthelmintic baits in additional roundworm-positive sites in western Virginia. These efforts could potentially reduce local roundworm prevalence to levels at which woodrat reintroductions in extirpated areas could be more successful.