Genetic diversity of Echinococcus multilocularis and Echinococcus granulosus sensu lato in Kyrgyzstan: The A2 haplotype of E. multilocularis is the predominant variant infecting humans

Abstract

Alveolar and cystic echinococcosis (AE, CE) caused by E. multilocularis and E. granulosus s.l., respectively, are considered emerging zoonotic diseases in Kyrgyzstan with some of the world highest regional incidences. Little is known regarding the molecular variability of both species in Kyrgyzstan. In this study we provide molecular data from a total of 72 parasite isolates derived from humans (52 AE and 20 CE patients) and 43 samples from dogs (23 infected with E. multilocularis and 20 with E. granulosus s.l.).Genetic variability in E. multilocularis was studied using the concatenated complete sequences of the cob, nad2 and cox1 mitochondrial genes adding a total of 3,558bp per isolate. The cob/nad2/cox1 A2 haplotype was identified in 63.4% of the human and in 65.2% of the dog samples. This haplotype was originally described in samples from Kazakhstan and St. Lawrence Island (Alaska, USA). We also describe here 16 non-previously defined variants of E. multilocularis (called A11-A26). All haplotypes cluster together within the Asian group in the haplotype network. Based on Fst values, low level of genetic differentiation was found between the populations of E. multilocularis isolated from different regions within the country. However, high degree of differentiation was found when all the concatenated sequences from Kyrgyzstan are considered as a single population and compared with the population of the parasite from the neighbouring country China. In the case of E. granulosus s.l. the analysis was based in 1,609bp of the cox1 gene. One isolate from a dog was identified as E. equinus, while all the other sequences were identified belonging to E. granulosus s.s. In total, 24 cox1 haplotypes of E. granulosus s.s. were identified including the already described variants: Eg01 (in 6 samples), Eg33 (in 4 samples), EgCl04 (in 2 samples), Eg03 (in 1 sample) and Eg32 (in 1 sample). From the twenty-five other isolates of E. granulosus s.s. a total of 19 non-PLOS NEGLECTED TROPICAL DISEASES

Association between environmental and climatic risk factors and the spatial distribution of cystic and alveolar echinococcosis in Kyrgyzstan

“…Although AE intermediate hosts have specific habitat requirements and thus landscape composition is considered as a proxy for their distribution [ 14 ], the lack of adequate data on AE intermediate hosts distribution and abundance also limits our study. Additionally, it remains unknown whether the emergence of AE in Kyrgyzstan might also be due to a higher virulence of the most common variant infecting humans in this country [ 40 ]. More data and genotyping of both human and definitive host populations might help understanding this issue.…”

Serological Assays for Alveolar and Cystic Echinococcosis—A Comparative Multi-Test Study in Switzerland and Kyrgyzstan

“…Kyrgyz serum samples of treatment-naïve patients included 40 AE and 23 CE patients that were diagnosed and had surgery at City Clinical Hospital #1 in Bishkek, Kyrgyzstan. Case inclusion criteria in both countries were solely based on positive PCR results [ 44 , 45 ] or immunohistochemical-stainings with monoclonal antibodies of resection specimens or biopsies [ 46 ]. Lesions were classified according to WHO standards [ 6 ] and clinical data was noted.…”

“…This European E. multilocularis isolate was initially described by Nakao et al (2009) [ 47 ] and was later found in France and Belgium. Molecular analysis was performed as described by Alvarez–Rojas et al (2020) [ 45 ].…”

LAMP Assay for the Detection of Echinococcus multilocularis Eggs Isolated from Canine Faeces by a Cost-Effective NaOH-Based DNA Extraction Method

“…in Kyrgyzstan between 2017 and 2018 [including a genetic characterisation of E . multilocularis [ 67 ] and identification by egg isolation + multiplex-PCR [ 15 ]]. In the study mentioned above, taeniid eggs were concentrated from dog faecal samples as previously described and DNA was isolated combining alkaline lysis and the QIAamp Kit [ 10 , 50 ].…”

“…In total, we used 32 faecal samples from dogs collected as part of a large prevalence study for Echinococcus spp. in Kyrgyzstan between 2017 and 2018 [including a genetic characterisation of E. multilocularis [67] and identification by egg isolation + multiplex-PCR [15]]. In the study mentioned above, taeniid eggs were concentrated from dog faecal samples as previously described and DNA was isolated combining alkaline lysis and the QIAamp Kit [10,50] Two aliquots of 400-500 mg were taken from faecal samples of 30 foxes infected with E. multilocularis and five from negative foxes from the same group of animals used for protocols 1A and 1B (diagnosed at necropsy/SCT).…”