State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, National Para-Reference Laboratory for Animal Echinococcosis, Key Laboratory of Veterinary Parasitology of Gansu Province Lanzhou Veterinary Research Institute, Lanzhou University, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, China.
Department of Veterinary Clinical Medicine and Epidemiology, Mekelle University, College of Veterinary Sciences, Kalamino Campus, P.O.Box: 2084, Mekelle, Tigray, Ethiopia.
Infect Dis Poverty. 2023 Aug 10;12(1):72. doi: 10.1186/s40249-023-01120-0.
In the normal life cycle of the parasite (Echinococcus multilocularis) that causes alveolar echinococcosis, domestic and wild carnivores act as definitive hosts, and rodents act as intermediate hosts. The presented study contributes to the research on the distribution and transmission pattern of E. multilocularis in China having identified sheep as an unusual intermediate host taking part in the domestic transmission of alveolar echinococcosis in Gansu Province, China.
From 2020 to 2021, nine whitish different cyst-like were collected from the liver of sheep in Gansu Province for examination. A near complete mitochondrial (mt) genome and selected nuclear genes were amplified from the cyst-like lesion for identification. To confirm the status of the specimen, comparative analysis with reference sequences, phylogenetic analysis, and network analysis were performed.
The isolates displayed ≥ 98.87% similarity to E. multilocularis NADH dehydrogenase sub-unit 1 (nad1) (894 bp) reference sequences deposited in GenBank. Furthermore, amplification of the nad4 and nad2 genes also confirmed all nine samples as E. multilocularis with > 99.30% similarity. Additionally, three nuclear genes, pepck (1545 bp), elp-exons VII and VIII (566 bp), and elp-exon IX (256 bp), were successfully amplified and sequenced for one of the isolates with 98.42% similarity, confirming the isolates were correctly identified as E. multilocularis. Network analysis also correctly placed the isolates with other E. multilocularis.
As a result of the discovery of E. multilocularis in an unusual intermediate host, which is considered to have the highest zoonotic potential, the result clearly demonstrated the necessity for expanded surveillance in the area.
在导致泡型包虫病的寄生虫（多房棘球绦虫）的正常生命周期中，家养和野生食肉动物是终末宿主，而啮齿动物是中间宿主。本研究在中国多房棘球绦虫的分布和传播模式研究中做出了贡献，在中国甘肃省发现绵羊作为一种不寻常的中间宿主参与泡型包虫病的国内传播。
2020 年至 2021 年，从甘肃省绵羊肝脏中采集了 9 个灰白色不同的囊状病变进行检查。从囊状病变中扩增了近乎完整的线粒体（mt）基因组和选定的核基因进行鉴定。为了确认标本的状态，与参考序列进行了比较分析、系统发育分析和网络分析。
分离株与保藏在 GenBank 中的多房棘球绦虫 NADH 脱氢酶亚单位 1（nad1）（894bp）参考序列的相似度≥98.87%。此外，nad4 和 nad2 基因的扩增也证实了这 9 个样本均为多房棘球绦虫，相似度＞99.30%。此外，还成功扩增和测序了三个核基因，即磷酸烯醇式丙酮酸羧激酶（pepck）（1545bp）、elp 外显子 VII 和 VIII（566bp）和 elp 外显子 IX（256bp），其中一个分离株的相似度为 98.42%，证实分离株被正确鉴定为多房棘球绦虫。网络分析也正确地将分离株与其他多房棘球绦虫放在一起。
由于在被认为具有最高人畜共患病潜力的不寻常中间宿主中发现了多房棘球绦虫，这一结果清楚地表明有必要在该地区扩大监测。
