High occurrence of Cryptosporidium ubiquitum and Giardia duodenalis genotype E in sheep from Brazil.

In this paper we report the occurrence of zoonotic species of Cryptosporidium (C. ubiquitum and C. parvum subtype IIaA15G2R1) and the host-specific Giardia duodenalis genotype E in a sheep farm from Brazil. Fecal specimens were collected from 100 animals and screened for the presence of G. duodenalis and Cryptosporidium spp. by enzyme immunoassay (EIA) and polymerase chain reaction (PCR). Restriction fragment length polymorphism (RFLP) and sequence analysis of selected samples was used to confirm the species and to characterize the isolates. Of 100 specimens, 34 were positive for Giardia (34%) and 25 were positive for Cryptosporidium (25%). The prevalence of Giardia and Cryptosporidium was higher in lambs than in ewes. Co-infection was observed in 14% of animals. All G. duodenalis isolates belonged to genotype E. The genetic characterization performed in 22 Cryptosporidium-positive samples revealed the presence of zoonotic C. ubiquitum and C. parvum in 76% (19/25) and 12% (3/25) of infected animals, respectively. The presence of zoonotic Cryptosporidium subtypes in lambs was of epidemiological and public health relevance.

Genetic characterisation of Giardia duodenalis in dairy cattle in Brazil.

The intestinal protozoan parasite Giardia duodenalis (Lambl, 1859) Kofoid & Christiansen, 1915 [syn. Giardia intestinalis and Giardia lamblia] has emerged as a widespread enteric pathogen in humans and domestic animals. In recent years, G. duodenalis has been found in cattle worldwide and longitudinal studies have reported cumulative prevalence of 100% in some herds. In the present study, we determined the prevalence and genetic characterisation of G. duodenalis in 200 dairy cattle from 10 dairy farms in São Paulo state, Brazil. All faecal specimens were screened for the presence of G. duodenalis using microscopy examination, enzyme immunoassay (EIA) and polymerase chain reaction (PCR). DNA was extracted from faecal samples and G. duodenalis were identified by amplification of the small subunit ribosomal (SSU-rDNA) and glutamate dehydrogenase (GDH) genes followed by restriction fragment length polymorphism (RFLP) or sequencing analysis. Giardia was identified in eight farm locations (80% prevalence). Overall, 15/200 (7.5%) animals were positive for infection, only one of which was a cow. Giardia duodenalis genotype E was present in 14 of the animals tested. Zoonotic genotype AI was present in one positive sample. Genotype E and genotype A represented 93% and 7% of G. duodenalis infections, respectively. This study demonstrates that G. duodenalis infection was prevalent in dairy calves in São Paulo state and that the non-zoonotic genotype E predominates in cattle in this region. Nevertheless, calves naturally infected in Brazil can shed Giardia cysts that can potentially infect humans, and thus, they may represent a public health risk.