Prevalence of Opisthorchis viverrini infection in the canine and feline hosts in three villages, Khon Kaen Province, northeastern Thailand.

To determine the current reservoir status and prevalence of Opisthorchis viverrini infection in endemic areas, 78 dogs and 22 cats were sampled for fecal examination in 3 villages along the Chi River in Khon Kaen Province, northeastern Thailand. Sex, age, color, identifiable markings, subjective body condition scores (BCS) and diet were recorded and analyzed. Fecal samples were evaluated using direct smear and modified formalin-ethyl acetate fecal assays. All parasites found were identified. In dogs and cats, the prevalences of O. viverrini infection were 3.8% and 36.4%, respectively. The highest prevalences of parasitic infection in both dogs and cats were Ancylostoma spp, in 64.1% and 77.3%, respectively. These results provide insight into the role of the canines and felines in maintaining the presence of O. viverrini eggs in the environment. If similar patterns occur on a broader scale, the zoonotic role of dogs and cats in the epidemiology of this disease should be considered in the development of improved control and education programs.