Prevalence of Baylisascaris procyonis in raccoon latrines in southern Ontario, Canada.

Raccoon latrines represent sites of potential infection by the zoonotic parasite Baylisascaris procyonis for wildlife and humans. Our objective was to determine the prevalence of B. procyonis at raccoon latrine sites in southern Ontario. Thirty raccoon latrines were sampled between June - July 2018; multiple scats were collected and homogenized to form a representative sample of each latrine. To determine the presence or absence of B. procyonis eggs in each sample, we used the Cornell-Wisconsin centrifugal floatation technique. Twenty-three percent (7/30) of homogenized samples tested positive for B. procyonis. Eggs per gram of feces ranged from 1 to 388 (median = 1.28, IQR = 0.32-232.5). Baylisascaris procyonis positive latrines were found in conservation areas heavily used by people, which may represent a possible source of exposure for humans in these areas.