Molecular characterization and zoonotic risk assessment of spp. in children and calves in Bangladesh.

is a gastro-intestinal protozoan parasite that has been found to infect both humans and livestock. This study investigated the parasite in 998 fecal samples from Bangladeshi children ( = 299) and calves ( = 699) to determine its prevalence, genetic variation, and zoonotic importance. The nested PCR and sequencing of the SSU rRNA gene in the samples showed a infection rate of 2.3% (7/299) in children and 15.7% (110/699) in calves. Statistical analysis revealed insignificant variations in infections among children across age, gender, and study area, while in calves, the infection rate significantly differed based on location and breed. Genotyping of seven human isolates of confirmed ( = 5) and ( = 2). After characterizing 110 isolates from calves, ( = 55), ( = 29), ( = 14), ( = 10), (n = 1), and (n = 1) were identified. and -positive samples were further subjected to nested PCR and sequencing of the glycoprotein 60 () gene for subtyping. Four subtypes (IaA19R3, IaA23R3, IbA9G3, and IdA15G1) and one subtype (IIdA15G1) were observed. In conclusion, was prevalent in calves but less common in children in the study locations, and the presence of zoonotic species and subtypes in calves raises concerns regarding zoonotic transmission to humans.