Baylisascaris procyonis, also known as the raccoon roundworm,  is the most common and widespread cause of clinical larva migrans in animals. It is a ubiquitous roundworm infection of raccoons (Procyon lotor) and is emerging as an important helminthic zoonosis, primarily in young children.

Raccoon image/CDC
Raccoon image/CDC

B. procyonis roundworms can cause potentially fatal neural larva migrans in many species, including humans. However, the clinical spectrum of baylisascariasis is not completely understood, according to researchers in a new study published in the CDC journal, Emerging Infectious Diseases.

Wildlife rehabilitators may represent a population at risk for subclinical baylisascariasis due to frequent contact with raccoons and their feces, which may contain infectious larvated B. procyonis eggs.

During 2012–2015, serum samples were collected and analyzed for B. procyonis IgG using a recombinant B. procyonis repeat antigen 1 protein Western blot. A questionnaire was also administered to determine current involvement in rehabilitation activities.

Nine out of 10 of the 347 participants  reported current involvement in rehabilitation activities.

Twenty-four, or 7 percent of participants tested positive for B. procyonis antibodies.

Based on their findings, researchers suggest that exposure to B. procyonis may occur without clinical disease. See study for details to include complete data and limitations.