Epidemiological, parasitological and molecular aspects of Giardia duodenalis infection in children attending public daycare centers in southeastern Brazil.

The purpose of this study was to determine the prevalence, associated risk factors and genotype of Giardia duodenalis infection in children attending public daycare centers in the city of Araguari, state of Minas Gerais, Brazil. Fecal samples were collected from 245 children aged 0-5 years, and questionnaires were asked about sociodemographic and hygiene-related characteristics. At the daycare centers where children tested positive, fecal samples were collected from the staff handling food, and from family members and domestic animals. Positive samples were analyzed at the dehydrogenase glutamate (gdh) locus to determine the genotype. The prevalence of G. duodenalis was 51.8%, and drinking unfiltered and unboiled water (OR 2.12, CI 1.26-3.69, p<0.001) and washing hands only with water (OR 2.14, CI 1.19-4.04, p<0.001) were related risk factors. No association was found between test-positive children and their family members, domestic animals and food handlers. An analysis of the sequences of 30 samples revealed that they all belonged to genotype B.