Occurrence and Phylogenetic Description of Cystic Echinococcosis Isolate from Egyptian Camel (Camelus Dromedarius)

Abstract

Cystic echinococcosis is one of the most significant cyclo-zoonotic diseases of major economic and public health significance worldwide. The current study was carried out to determine the epidemiological profile of cystic echinococcosis as well as to investigate its molecular and phylogenic status from one-humped camel (Camelus dromedarius) in the southern region of Egypt. In the present work, 110 camels freshly slaughtered at Daraw abattoirs, Aswan governorate were inspected for the presence of Hydatid cysts (HCs) visually and manually by palpation and incision, over a period of one year (June, 2018 - May, 2019). Furthermore, fourteen fertile hydatid cyst samples were collected from lungs of slaughtered camels. DNA extraction from two fertile samples was successfully achieved followed by phylogenetic analysis on two mitochondrial genes (cox1and nad1). Out of 110 camels slaughtered 11 (10 %) were found harboring hydatid cysts. The infection was found to prevail throughout the year, with the highest peak encountered in winter (45.5 %). The lungs were the most frequently infected organs (72.7 %) with liver cysts occurring at a significantly lower rate (27.3 %). The mean value of total protein, glucose, urea, cholesterol, magnesium, potassium, copper and creatinine was higher in cystic fluid from camels as compared to cattle. Blast and phylogenetic analysis on sequenced genes showed the presence of Echinococcus intermedius, originally the pig genotype (G7) in camels for the first time in Egypt. To the best of our knowledge, the current research provides a description of the current epidemiological and molecular situation of camel hydatidosis in the southern region of Egypt. Furthermore, the current results may have significant implications for hydatid disease control in the studied region.

Keywords: Camelus dromedarius; Cystic echinococcosis; Egypt; Epidemiological status; Molecular characterization.

Fig. 1

a, b) Calcified cyst; c) Protoscoleces; d) Multiple fertile cysts in the lung (yellow arrow head).

Fig. 2

Agarose (1.5%) gel electrophoresis of PCR-products of cox1 gene (450bp) of E. granulosus isolates in camel samples. L: ladder, Pos.: positive control, Neg.: negative control, 1, 2, 3, 4and 5 samples (all +ve).

Fig. 3

Agarose (1.5%) gel electrophoresis of PCR-products of Nad1 gene (500bp) of E. granulosus isolates in camel samples. L: ladder, Pos.: positive control, Neg.: negative control, 1, 2, 3,4and 5 samples (all +ve).

Fig. 4

Genetic relationships of the obtained genotypes from camel in the present study and reference sequences related genotypes of E. granulosus as well as Taenia saginata as the outgroup. The relationships were inferred based on phylogenetic tree (cox1 gene). The phylogenetic tree was constructed using Maximum Likelihood Tree implemented in MEGA software version 6.

Fig. 5

Genetic relationships of the obtained genotypes from camel in the present study and reference sequences related genotypes of E. granulosus as well as Taenia saginata as the out-group. The relationships were inferred based on phylogenetic tree (nad1 gene). The phylogenetic tree was constructed using Maximum Likelihood Tree implemented in MEGA software version 6.