Survey of giardiosis in household and shelter dogs from metropolitan areas of Curitiba, Paraná state, Southern Brazil

Giardia duodenalis is a protozoan parasite that causes a broad range of clinical symptoms varying from none – in asymptomatic carriers – to mild recurring diarrhea consisting of soft, light-colored stools to acute severe diarrhea. In different parts of the world this parasite has raised increased interest due to its possible zoonotic transmission. Among domestic animals, dogs can play an important role in environmental contamination. As there is little information on the frequency of giardiosis in dogs from the Metropolitan Area of Curitiba—State of Paraná, Southern Brazil, the aim of the present work was to evaluate the prevalence of G. duodenalis in two dog populations (household and shelter). To attain the proposed aim, we collected fecal samples from 200 dogs and utilized three diagnostic techniques: Faust's technique (Faust et al. 1939), Benbrook's technique (1963) and polymerase chain reaction (PCR). Faust's technique presented the best results, as it was able to detect a larger number of Giardia cases. Taking Faust's technique as the standard, Benbrook's technique presented 66% sensitivity and PCR demonstrated 69% sensitivity. The shelter dog population showed a 24% occurrence of G. duodenalis while the household population showed a 9% occurrence. Other epidemiological aspects like age, sex, environmental conditions and methodological aspects are discussed in the present article.