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The neglected zoonosis cystic echinococcosis affects mainly pastoral and rural communities in both low-income and upper-middle-income countries. In Europe, it should be regarded as an orphan and rare disease. Although human cystic echinococcosis is a notifiable parasitic infectious disease in most European countries, in practice it is largely under-reported by national health systems. To fill this gap, we extracted data on the number, incidence, and trend of human cases in Europe through a systematic review approach, using both the scientific and grey literature and accounting for the period of publication from 1997 to 2021. The highest number of possible human cases at the national level was calculated from various data sources to generate a descriptive model of human cystic echinococcosis in Europe. We identified 64 745 human cystic echinococcosis cases from 40 European countries. The mean annual incidence from 1997 to 2020 throughout Europe was 0·64 cases per 100 000 people and in EU member states was 0·50 cases per 100 000 people. Based on incidence rates and trends detected in this study, the current epicentre of cystic echinococcosis in Europe is in the southeastern European countries, whereas historical endemic European Mediterranean countries have recorded a decrease in the number of cases over the time., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Echinococcus granulosus sensu stricto (s.s.) is the major cause of human cystic echinococcosis worldwide and is listed among the most severe parasitic diseases of humans. To date, numerous studies have investigated the genetic diversity and population structure of E. granulosus s.s. in various geographic regions. However, there has been no global study. Recently, using mitochondrial DNA, it was shown that E. granulosus s.s. G1 and G3 are distinct genotypes, but a larger dataset is required to confirm the distinction of these genotypes. The objectives of this study were to: (i) investigate the distinction of genotypes G1 and G3 using a large global dataset; and (ii) analyse the genetic diversity and phylogeography of genotype G1 on a global scale using near-complete mitogenome sequences. For this study, 222 globally distributed E. granulosus s.s. samples were used, of which 212 belonged to genotype G1 and 10 to G3. Using a total sequence length of 11,682 bp, we inferred phylogenetic networks for three datasets: E. granulosus s.s. (n = 222), G1 (n = 212) and human G1 samples (n = 41). In addition, the Bayesian phylogenetic and phylogeographic analyses were performed. The latter yielded several strongly supported diffusion routes of genotype G1 originating from Turkey, Tunisia and Argentina. We conclude that: (i) using a considerably larger dataset than employed previously, E. granulosus s.s. G1 and G3 are indeed distinct mitochondrial genotypes; (ii) the genetic diversity of E. granulosus s.s. G1 is high globally, with lower values in South America; and (iii) the complex phylogeographic patterns emerging from the phylogenetic and geographic analyses suggest that the current distribution of genotype G1 has been shaped by intensive animal trade., (Copyright © 2018 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.)

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]

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]