Ascarid infection is a serious health threat to humans and a wide variety of animals. Although Baylisascaris procyonis is known as the raccoon roundworm, it has a large and varied host range and has been identified in approximately 90 species of domestic, commercial, and wild animals, from broiler chickens to pet dogs. Like most ascarids, B procyonis can also infect humans. Migrating larvae can traverse large areas of the body and cause permanent damage as they move through tissues. Many studies have documented the presence of B procyonis in the Midwest, Northeast, and Pacific West, with the highest concentrations of the parasite found in mountain regions of Virginia, Kentucky, and West Virginia. Recently, the geographic range of the parasite has been expanding. Last year it was identified in 2 urban areas of northern Georgia, with between 10% and 22% of sampled raccoons testing positive. The current report describes the initial finding of B procyonis in Florida. As recently as 2005, surveys examining ascarid prevalence throughout Florida have failed to identify B procyonis. However, the current report documents the species in raccoons from several northwestern and southeastern Florida counties between 2006 and 2010. All of the infected animals were diagnosed after their arrival at a wildlife rehabilitation facility.

Commentary: Both raccoons and dogs are definitive hosts for B procyonis, so infected dogs can pass eggs in their feces. Transportation of infected dogs from endemic areas may have a role in expansion of the species into southern states. Many dogs harboring B procyonis are also infected with other nonzoonotic roundworms, so clinicians should examine all fecal samples with great care to properly identify ascarid species. Pet owners should be advised of the potential health risk associated with contracting B procyonis infection and should be advised to maintain a strict deworming schedule.—Carly Jordan, PhD candidate

Geographic expansion of Baylisascaris procyonis roundworms, Florida, USA. Yabsley MJ, Blizzard AL, Beck MF, Harsch S. EMERG INFECT DIS doi: 10.3201/eid1611.100549.