Presence of human Giardia in domestic, farm and wild animals, and environmental samples suggests a zoonotic potential for giardiasis.
Giardia lamblia which parasitize humans belong to either of two genotypes, A or B, based on specific signature sequences in the 5' end of the small subunit (16S) ribosomal RNA (rRNA) gene. These two genotypes also were found in cysts from fecal samples of animal origin such as dogs, cats, some farm animals and wild animals. In addition, trophozoites recovered from cysts obtained from environmental samples belonged to these two genotypes as well, suggesting that the G. lamblia genotypes A and B are widespread and possibly zoonotic. Trophozoites were recovered from rats and these isolates might belong to another genotype of G. lamblia. Deer mice and one dog appeared to be parasitized by genotypes of Giardia with close affinity to G. microti. This species, therefore, also consists of a genotype complex.
SourceVeterinary parasitology 108:2 2002 Sep 10 pg 97-107
Molecular Sequence Data
Polymerase Chain Reaction
Polymorphism, Restriction Fragment Length
RNA, Ribosomal, 16S
Sequence Homology, Nucleic Acid
Pub Type(s)Journal Article
Research Support, Non-U.S. Gov't