Limited Range of Genetic Variation in \u3ci\u3eEchinococcus multilocularis\u3c/i\u3e

DNA sequencing of 1.3 kb of rDNA containing both internal transcribed spacers (ITS1, ITS2) and adjoining rRNA coding regions in each of 11 Echinococcus multilocularis isolates from Germany, Japan, and Alaska resulted in identical nucleotide sequences except for a single polymorphic locus 54 bp upstream of the 3\u27 end of the 18S coding region, separating Eurasian isolates from an Alaskan isolate. The same base substitution was found in each of two additional isolates from Alaska. The distribution of the resulting genotypes with regard to their origin is highly significant (\u3e99.9%) and corresponds to the traditional subspecies Echinococcus multilocularis multilocularis and Echinococcus multilocularis sibiricensis

Zoonotic Potential of Enterocytozoon bieneusi

The reservoirs and the modes of transmission of the most frequent microsporidial species in humans, Enterocytozoon bieneusi, are still unknown. We have examined fecal samples of 26 humans and 350 animals from 37 species to find 18 samples containing this parasite from humans, cats, pigs, cattle, and a llama. Genotypic characterization of the internal transcribed spacer of the rRNA gene resulted in 14 different genotypes, 6 of them previously undescribed. Phylogenetic analysis revealed the lack of a transmission barrier between E. bieneusi from humans and animals (cats, pigs, and cattle). Thus, E. bieneusi appears to be a zoonotic pathogen