In:
Parasites & Vectors, Springer Science and Business Media LLC, Vol. 12, No. 1 ( 2019-12)
Abstract:
Cystic echinococcosis (CE) in humans and livestock is caused by Echinococcus granulosus ( sensu lato ). In China where CE is endemic, a number of studies have shown that Echinococcus granulosus ( sensu stricto ) is majorly responsible for CE. However, E. canadensis (G6) which is the second leading cause of CE is now being detected in most parts of the country. In this study, the species diversity and genetic variation of Echinococcus granulosus ( s.l. ) in four counties in Tibet Autonomous Region of China were investigated. Methods Infection with Echinococcus granulosus ( s.s. ) in yaks and sheep was identified using NADH dehydrogenase subunit 1 and 5 ( nad 1 and nad 5) mitochondrial genes while the genotype G6 of E. canadensis initially diagnosed with NADH dehydrogenase subunit 1 ( nad 1) was further confirmed by analysis of the complete mitochondrial genome and a phylogenetic network constructed based on the nad 2 and nad 5 genes. Results Out of 85 hydatid cyst samples collected from slaughtered sheep ( n = 54) and yaks ( n = 31), 83 were identified as E. granulosus ( s.s. ) G1 ( n = 77), G3 ( n = 6) and 2 were identified as E. canadensis G6. Analysis of the nad 1/ nad 5 genes revealed 16/17 mutations with 9/14 parsimony informative sites resulting in 15/14 haplotypes, respectively. Haplotype diversity (Hd) and nucleotide diversity (π) of E. granulosus ( s.s. ) population were 0.650 and 0.00127 for nad 1 and 0.782 and 0.00306 for nad 5, respectively, with an overall negative Tajima’s D and Fu’s Fs. A low F ST indicated no genetic difference between isolates from sheep and yaks. Conclusion Pockets of infection with E. canadensis (G6, G7, G8 and G10) have been previously reported in sheep, goats, yaks and/or humans in different parts of China. While the G6 genotype has been previously reported in sheep in the Tibet Autonomous Region, the detection in a yak in the present study represents the first to the best of our knowledge. Therefore, we recommend future surveys and control efforts to comprehensively investigate other potential intermediate hosts for the prevalence and genetic diversity of the E. canadensis group (G6, G7, G8 and G10) across the country and their inclusion into the existing CE control programme.
Type of Medium:
Online Resource
ISSN:
1756-3305
DOI:
10.1186/s13071-019-3857-1
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2019
detail.hit.zdb_id:
2409480-8
