title: Molecular characterization of Echinococcus granulosus isolates from Bulgarian human cystic echinococcosis patients.
abstract: Although cystic echinococcosis (CE) is highly endemic in Bulgaria, there is still scarce information about species and/or genotypes of the Echinococcus granulosus complex that infect humans. Our study tackled the genetic diversity of E. granulosus complex in a cohort of 30 Bulgarian CE patients. Ten animal E. granulosus isolates from neighboring Greece were additionally included. Specimens were comparatively analyzed for partial sequences of five mitochondrial (mt) (cox I, nad I, rrnS, rrnL, and atp6) and three nuclear (nc) genes (act II, hbx 2, and ef-1α) using a PCR-sequencing approach. All 30 Bulgarian isolates were identified as E. granulosus sensu stricto (s.s.) and were showing identical sequences for each of the three examined partial nc gene markers. Based upon concatenated sequences from partial mtDNA markers, we detected 10 haplotypes: 6 haplotypes (H1-H6) clustering with E. granulosus s.s. (G1) and 4 haplotypes (H9-H13) grouping with E. granulosus s.s. (G3), with H1 and H10 being the most frequent in Bulgarian patients. The haplotypes H1, H4, and H11 were also present in Greek hydatid cyst samples of animal origin. In conclusion, E. granulosus s.s. (G1 and G3 genotypes) is the only causative agent found so far to cause human CE in Bulgaria. However, further studies including larger sample sizes and other additional geographic regions in Bulgaria will have to be performed to confirm our results.
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty and Faculty of Medicine, University of Bern, 3012, Bern, Switzerland.|Department of Parasitology and Tropical Medicine, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Irina
authors.initials: I
authors.lastname: Marinova
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty and Faculty of Medicine, University of Bern, 3012, Bern, Switzerland.
authors.forename: Markus
authors.initials: M
authors.lastname: Spiliotis
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty and Faculty of Medicine, University of Bern, 3012, Bern, Switzerland.
authors.forename: Junhua
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Parasitology and Tropical Medicine, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.|Multi-Profile Hospital for Active Treatment "Kardzhali", Gastroenterology Ward, Kardzhali, Bulgaria.
authors.forename: Marin
authors.initials: M
authors.lastname: Muhtarov
authors.affiliation: Hellenic Agricultural Organisation-Demeter, Veterinary Research Institute, Thessaloniki, Greece.
authors.forename: Ilias
authors.initials: I
authors.lastname: Chaligiannis
authors.affiliation: Hellenic Agricultural Organisation-Demeter, Veterinary Research Institute, Thessaloniki, Greece.
authors.forename: Smaro
authors.initials: S
authors.lastname: Sotiraki
authors.affiliation: Department of Parasitology and Tropical Medicine, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Iskra
authors.initials: I
authors.lastname: Rainova
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty and Faculty of Medicine, University of Bern, 3012, Bern, Switzerland. bruno.gottstein@vetsuisse.unibe.ch.
authors.forename: Bruno
authors.identifier: http://orcid.org/0000-0003-0782-3723
authors.initials: B
authors.lastname: Gottstein
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty and Faculty of Medicine, University of Bern, 3012, Bern, Switzerland.|Department of Clinical Biology B, Laboratory of Medical and Molecular Parasitology-Mycology (LR12ES08), Faculty of Pharmacy, University of Monastir, Monastir, Tunisia.
authors.forename: Ghalia
authors.initials: G
authors.lastname: Boubaker
mesh_terms: D000818:Animals; D002031:Bulgaria / Q000453:epidemiology; D004272:DNA, Mitochondrial / Q000235:genetics; D004443:Echinococcosis / Q000453:epidemiology / Q000469:parasitology*; D048209:Echinococcus granulosus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D014644:Genetic Variation; D005838:Genotype; D006115:Greece; D006239:Haplotypes; D015801:Helminth Proteins / Q000235:genetics; D006801:Humans; D020648:Peptide Elongation Factor 1 / Q000235:genetics
chemical_list: D004272:DNA, Mitochondrial; D015801:Helminth Proteins; D020648:Peptide Elongation Factor 1
keywords: Echinococcus spp.; Genotyping; Mitochondrial markers; Nuclear markers; PCR; Speciation