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Introduction: Cystic echinococcosis is a globally distributed zoonotic disease of great medical and veterinary importance, which is caused by the cestode Echinococcus granulosus sensu lato. In Ukraine, two areas of the prominent circulation of the parasite are established, the southern steppe zone with sheep as the main transmitter, and the northern forest-steppe zone and Polissia, where pigs are mainly responsible for maintaining the E. granulosus transmission. Methods: Given that only a few studies have so far addressed the genetic diversity of the parasite in Ukraine, we have sequenced partial mitochondrial genes of cytochrome c oxidase 1 (789 bp), NADH dehydrogenase 1 (602 bp) and 12S rRNA (333–334 bp) in pig metacestodes from the Sumy region (farms close to Sumy, northeastern Ukraine) and the Kyiv region (a farm in Bila Tserkva, central Ukraine). Results: Four isolates from four pigs in the Sumy region were identified as E. canadensis (G7 genotype), the major E. granulosus s.l. species circulating in Eastern Europe, including the three microvariants (G7A, G7B, G7C). Three isolates from the two pigs in the Kyiv region were classified as E. granulosus s.s. (G1 genotype), including one microvariant (G1A). Conclusion: To our knowledge, this is the first genetic record of E. granulosus s.s. with the presumed highest infectivity and virulence among the E. granulosus s.l. species in Ukraine. The finding has implications for public health as local control programmes should take into consideration different development rate of this parasite in dogs and the greater risk of the species for human infection. [ABSTRACT FROM AUTHOR]

Cystic echinococcosis (CE) is a severe parasitic disease caused by the species complex Echinococcus granulosus sensu lato. Human infections are most commonly associated with E. granulosus sensu stricto (s.s.), comprising genotypes G1 and G3. The objective of the current study was to provide first insight into the genetic diversity and phylogeography of genotype G3. Despite the epidemiological importance of the genotype, it has remained poorly explored due to the ambiguity in the definition of the genotype. However, it was recently demonstrated that long sequences of mitochondrial DNA (mtDNA) provide a reliable method to discriminate G1 and G3 from each other. Therefore, we sequenced near-complete mtDNA of 39 G3 samples, covering most of the known distribution range and host spectra of the genotype. The phylogenetic network revealed high genetic variation within E. granulosus s.s. G3 and while G3 is significantly less prevalent worldwide than G1, the genetic diversity of both of the genotypes is equally high. We also present the results of the Bayesian phylogeographic analysis, which yielded several well-supported diffusion routes of genotype G3 originating from Turkey and Iran, suggesting the Middle East as the origin of the genotype. [ABSTRACT FROM AUTHOR]

Cystic echinococcosis is one of the most important zoonotic diseases affecting humans and livestock worldwide, and is endemic in Poland. A set of six isolates on larval stages of Echinococcus granulosus sensu lato tapeworms collected from three humans, two pigs and one sheep from Polish foci of CE was examined by DNA sequencing of two mitochondrial genes ( cox1, rrnS). The results demonstrated the presence of E. canadensis and E. granulosus sensu stricto in the investigated hydatid cysts. The former species was found in all five isolates from pigs and humans derived from central Poland. In a sheep hydatid cyst originating from Lesser Poland Voivodeship in southern Poland, E. granulosus s. s. (G1 genotype) was identified. This is the first report of an unambiguously autochthonous infection with E. granulosus s. s. in Poland. The global distribution and host affiliations of the commonly occurring G1 microvariant with nucleotide change 56C/T in cox1, detected here in Polish sheep, are discussed. The finding that sheep harboured E. granulosus s. s. may have important consequences for developing effective hydatid control programmes in Poland due to its longer maturation rate in dogs compared with E. canadensis G7. This may lead to greater expenditures for purchasing anthelmintics to provide an appropriate dosing regime in sheep-raising areas of the country. [ABSTRACT FROM AUTHOR]

Children are most prone to parasitic infections. The objectives of the study were to examine the occurrence of parasitic infections in children from different populations and to perform molecular characterization of human Giardia duodenalis isolates. We examined 631 stool samples from Roma and non-Roma children for the presence of parasitic developmental stages. Samples were collected from three eastern Slovakia districts. The ages of the children ranged from 1 months to 17 years. Subsequently, the molecular characterization of human G. duodenalis isolates by PCR detected triosephosphate isomerase (tpi) and beta-giardin (bg) genes was performed. The overall prevalence of parasitic infection was 19.8%. Ascaris lumbricoides eggs were the most frequent, with an occurrence of about 13.8%. G. duodenalis cysts were present in 6.3% of samples. G. duodenalis isolates obtained from 13 children were subjected to DNA sequencing with tpi and bg genes. Five isolates were categorized as bearing subassemblage BIII, the three isolates as subassemblage BIV, one person was infected with a mixture of subassemblages BIII and BIV, four children had subassemblage AII, and one isolate revealed a structure corresponding with subassemblage AI. Our work is proof that poverty and poor hygiene contribute the most to public health problems associated with neglected parasitic diseases. [ABSTRACT FROM AUTHOR]

The larval stages of tapeworms in the species complex Echinococcus granulosus sensu lato cause a zoonotic disease known as cystic echinococcosis (CE). Within this species complex, genotypes G6 and G7 are among the most common genotypes associated with human CE cases worldwide. However, our understanding of ecology, biology and epidemiology of G6 and G7 is still limited. An essential first step towards this goal is correct genotype identification, but distinguishing genotypes G6 and G7 has been challenging. A recent analysis based on complete mitogenome data revealed that the conventional sequencing of the cox1 (366 bp) gene fragment mistakenly classified a subset of G7 samples as G6. On the other hand, sequencing complete mitogenomes is not practical if only genotype or haplogroup identification is needed. Therefore, a simpler and less costly method is required to distinguish genotypes G6 and G7. We compared 93 complete mitogenomes of G6 and G7 from a wide geographical range and demonstrate that a combination of nad2 (714 bp) and nad5 (680 bp) gene fragments would be the best option to distinguish G6 and G7. Moreover, this method allows assignment of G7 samples into haplogroups G7a and G7b. However, due to very high genetic variability of G6 and G7, we suggest to construct a phylogenetic network based on the nad2 and nad5 sequences in order to be absolutely sure in genotype assignment. For this we provide a reference dataset of 93 concatenated nad2 and nad5 sequences (1394 bp in total) containing representatives of G6 and G7 (and haplogroups G7a and G7b), which can be used for the reconstruction of phylogenetic networks. • Analysis of nad2 and nad5 is required for identification of E. granulosus s.l. genotypes G6 and G7 • Constructing a phylogenetic network is also required for genotype assignment • We provide reference sequences of G6-G7 for helping to build phylogenetic networks [ABSTRACT FROM AUTHOR]