Risk Factors Associated with Soil-Transmitted Helminths in Dog Feces That Contaminate Public Areas of Warsaw, Poland

A constant increase in dog numbers, especially in large towns, has been observed recently. The presence of dogs in urban spaces increases the risk of pollution by dogs' feces, which may contain growth forms of parasites including canine, soil-transmitted helminths (cSTHs), most of which have a proven zoonotic potential. This study assessed the frequency of occurrence and estimated the potential risk associated with the presence of cSTHs in dogs' feces left uncollected in urban areas. The study material consisted of 200 fecal samples obtained from city and dog parks situated in selected Warsaw districts. Each fecal sample was processed using the flotation technique. Eggs of cSTHs, including Toxocara canis, Toxascaris leonina, Trichuris vulpis, and hookworms from the Ancylostomatidae family were found in 23 (11.5%) of the examined fecal samples. The most prevalent species were hookworms from the family Ancylostomatidae (8%). The presence of parasites was confirmed in 14 out of 20 studied locations (70%), including eight city parks (72.7%) and six dog parks (66.7%). City and dog parks did not differ significantly in the frequency of parasite occurrence. This study indicated that dogs' feces, left uncollected, may cause environmental contamination with cSTHs. It also indicated that the presence of dogs' feces in public areas and the associated presence of parasites is still a problem.