Molecular survey on cattle and sheep hydatidosis and first detection of Echinococcus canadensis (G6/G7) in sheep in Turkey

Molecular discrimination of G1 and G3 genotypes of Echinococcus granulosus sensu stricto obtained from human, cattle, and sheep using the mitochondrial NADH dehydrogenase subunit 5 marker

Cystic echinococcosis (CE) is a common zoonotic disease caused by the larval form of Echinococcus granulosus sensu lato. This study determined the genotype and haplotype differences using the NADH dehydrogenase subunit 5 gene in hydatid cyst samples. Human (n = 12), cattle (n = 28), and sheep (n = 31) hydatid cyst isolates were included. Seventy-one genomic DNA samples were successfully extracted, and a 759 bp mitochondrial NADH dehydrogenase subunit 5 gene fragment was amplified by PCR. Following the sequence analysis, E. granulosus sensu stricto isolates were identified as G1 (n = 61) and G3 (n = 10). A total of 23 haplotypes were obtained from the 71 E. granulosus s.s. G1 and G3 samples. The main haplotype was Hap01 (60.56 %), which consisted of the G1 genotype. The second largest haplotype was Hap04, which consisted entirely of the G3 genotype. Hap14 acted as a bridge between the G1 and G3 genotypes. This study identifies G1 as the dominant genotype in humans and farm animals in Turkey. High haplotype and nucleotide diversity in genotypes were observed. Additionally, this is the first report on the phylogeography and gene flow models of the E. granulosus s.s. population in Turkey using the NADH dehydrogenase subunit 5 gene, the best marker distinguishing between G1 and G3 genotypes.

Investigation of Mitochondrial Cytb Gene Region of Both Echinococcus granulosus Eggs from Dogs and Cystic Echinococcosis Isolates Obtained from Sheep and Cattle by Molecular Methods

Background

We aimed to determine the common Echinococcus granulosus genotypes in Ağrı, Türkiye and to obtain information on the transmission of this parasite.

Methods

Cystic echinococcosis samples from 100 slaughtered cattle and 100 slaughtered sheep and faecal samples from 200 stray dogs were included in 2021. Collected cyst fluid samples and faces were examined microscopically. DNA was isolated from the germinal membrane of the cysts and from the parasite eggs in the stool samples. The mitochondrial cytb gene region of the parasite was amplified by PCR. Genotypes were determined using the Basic Local Alignment Search Tool (BLAST) after sequence analysis of PCR amplicons.

Results

The highest percentage of cysts was found in the lungs of sheep and the liver of cattle. In addition, 75% of sheep cysts and 25.6% of cattle cysts were fertile. Taenia spp./Echinococcus spp. eggs were found in 6% of the faeces of 200 dogs examined microscopically. E. granulosus eggs were detected in 4 out of 50 stool samples analysed by PCR. All samples analysed by sequence analysis were identified as E. granulosus s.s. G1 genotype. Sequence comparison revealed revealed one or more-point mutations in different regions of the five samples.

Conclusion

E. granulosus s.s. G1 genotype, known as sheep strain, is common in the Ağrı, Türkiye. The controlled slaughter of livestock, especially sheep, and the avoidance of feeding hydatid cyst organs to dogs, together with public education, were necessary to prevent the spread of the disease.

Echinococcus granulosus comparative genotyping in sheep in Saudi Arabia and Egypt

Background

Cystic echinococcosis (CE), which is triggered by the parasite Echinococcus granulosus, is a global zoonotic disease that is common in rural regions in which there are frequent encounters between dogs and other domestic animals. The disease can have devastating consequences, impacting the health of people and animals and leading to huge financial losses, especially in the agricultural industry. In the Kingdom of Saudi Arabia (KSA) and Egypt, despite the high incidence of disease, few investigations have been conducted into the genetic variation in species of the genus Echinococcus.

Aim

This study sought to compare the genetic features of the hydatid cysts carried in sheep in KSA with those found in Egypt.

Methods

DNA from the protoscolices was used in a PCR targeting the mitochondrial NADH dehydrogenase 1 (NAD1), cytochrome c oxidase subunit 1 (COX1), and nuclear actin II (ACT II) genes, and the resulting amplification products of 30 KSA and Egyptian isolates were sequenced and compared.

Results

Among the sheep in KSA, the overall prevalence of CE was 0.51%. Of the sheep cyst DNA samples, 95%, 100%, and 52% were positive for the Cox1, nad1, and act II genes, respectively. Targeting all three genes, all KSA samples belonged to the E. granulosus genotype (G1), whereas all Egyptian isolates belonged to E. granulosus (G1) and E. canadensis (G6).

Conclusion

We conclude that isolates of E. granulosus from the two countries shared a common origin in Arabic North Africa, with sheep and camels as common hosts.

Update on the genetic diversity and population structure of Echinococcus granulosus in Gansu Province, Tibet Autonomous Region, and Xinjiang Uygur Autonomous Region, Western China, inferred from mitochondrial cox1, nad1, and nad5 sequences

The identification of additional Echinococcus granulosus sensu lato (s.l.) complex species/genotypes in recent years raises the possibility that there might be more variation among this species in China than is currently understood. The aim of this study was to explore intra- and inter-species variation and population structure of Echinococcus species isolated from sheep in three areas of Western China. Of the isolates, 317, 322, and 326 were successfully amplified and sequenced for cox1, nad1, and nad5 genes, respectively. BLAST analysis revealed that the majority of the isolates were E. granulosus s.s., and using the cox1, nad1, and nad5 genes, respectively, 17, 14, and 11 isolates corresponded to Elodea canadensis (genotype G6/G7). In the three study areas, G1 genotypes were the most prevalent. There were 233 mutation sites along with 129 parsimony informative sites. A transition/transversion ratio of 7.5, 8, and 3.25, respectively, for cox1, nad1, and nad5 genes was obtained. Every mitochondrial gene had intraspecific variations, which were represented in a star-like network with a major haplotype with observable mutations from other distant and minor haplotypes. The Tajima's D value was significantly negative in all populations, indicating a substantial divergence from neutrality and supporting the demographic expansion of E. granulosus s.s. in the study areas. The phylogeny inferred by the maximum likelihood (ML) method using nucleotide sequences of cox1-nad1-nad5 further confirmed their identity. The nodes assigned to the G1, G3, and G6 clades as well as the reference sequences utilized had maximal posterior probability values (1.00). In conclusion, our study confirms the existence of a significant major haplotype of E. granulosus s.s. where G1 is the predominant genotype causing of CE in both livestock and humans in China.

Co-infection of Echinococcus equinus and Echinococcus canadensis (G6/7) in a gray wolf in Turkey: First report and genetic variability of the isolates

Cystic echinococcosis (CE) is an important zoonotic diseases caused by larval form of Echinococcus granulosus sensu lato. The material of this study was the gray wolf (Canis lupus), which was found dead in the rural area of Bingol province of Turkey. The animal was brought to Veterinary Faculty for necropsy and many of adult Echinococcus spp. obtained. A total of 9 whole adult worms were morphologically examined under the microscope, gDNA was isolated from individual samples, a partial mt-CO1 gene fragment (875 bp) was amplified with PCR and sequenced. According to the phylogenetic analysis, six worms were characterized as E. equinus, while three were reported as E. canadensis (G6/7). It was found that the haplotypes of both species were similar to previously published haplotypes. This is the first report in which E. equinus and E. canadensis (G6/7) adult parasites were detected together in a gray wolf's intestine. The findings are important in that it draws attention to the importance of wild cycle in the spread of CE.

Survey and Molecular Characterization of Echinococcus granulosus sensu stricto from Livestock and Humans in the Altai Region of Xinjiang, China

Cystic echinococcosis (CE), caused by the metacestode Echinococcus granulosus sensu stricto (s.s.), is an important zoonotic parasite, endemic in the Altai region of China. It is a serious human health risk and causes livestock losses. To evaluate the prevalence, genetic variation, and population structure of CE, 2898 sheep and 703 cattle were examined from October 2019 to mid-February 2020 in the Altai region (Altai, Habahe, Fuhai, and Buerjin). Sheep had an infection rate of 4.52% (131/2898) and cattle had an infection rate of 4.84% (34/703). In total, 180 cyst isolates were obtained, including 131 sheep, 34 cattle, and 15 from CE human patients. The cysts were investigated using mitochondrial cytochrome C oxidase subunit 1 (cox1). Polymerase Chain Reaction (PCR) results showed that, among the two genotypes of E. granulosus s.s., there were 22 different haplotypes (Haps). Phylogenetic analysis and parsimony network indicated that seventeen (77.27%) Haps belonged to the sheep strain (G1 genotype) and five Haps (22.73%) belonged to the buffalo strain (G3 genotype). Hap3 was the most common haplotype (65.00%, 112/180), which belongs to the G1 genotype. Hap18−Hap22 were found in human samples, indicating that sheep and cattle reservoirs of human CE. Molecular diversity indices revealed the high levels of haplotype diversity and relatively low levels of nucleotide diversity. Tajima’s D and Fu’s Fs tests displayed that the Altai population had a significant deviation from neutrality. Based on pairwise fixation index (Fst) values, a low level of genetic differentiation was found between the populations of E. granulosus s.s. isolated from different regions. The present survey findings represent an epidemiological survey of CE in the Altai region where there were two genotypes simultaneously and will provide more information on the genetic structure of E. granulosus s.s. within this region.

An overview of the genetic diversity of Echinococcus granulosus sensu lato in Turkey

Echinococcus granulosus is a parasite that lives as a host in animals and humans, causes great economic damage and poses a serious threat to health. Morphological differences and intermediate host preference are used to distinguish the species of this parasite. Ten genotypes and lion strains of Echinococcus granulosus have been identified in molecular studies to date. It contributes to the fact that the effects of cystic echinococcosis detected in humans and the disease process caused by different genotypes can be handled differently. In genetic diversity analysis, species were classified as Echinococcus granulosus sensu stricto, Echinococcus equinus, Echinococcus ortleppi, Echinococcus canadensis and Echinococcus felidis genotypes. Echinococcus granulosus sensu stricto is the most common cause of human cystic echinococcosis worldwide and in Turkey. In this review, the distribution and epidemiology of Echinococcus granulosus genotypes detected in humans and animals in Turkey are discussed.

Genetic Diversity and Haplotype Analysis of Cattle Hydatid Cyst Isolates Using Mitochondrial Markers in Turkey

Echinococcus granulosus sensu lato (s.l.) causes cystic echinococcosis in ungulates and humans. The current study was designed to find the genetic diversity and haplotypic profiles of hydatid cysts from the lungs of cattle in three provinces in eastern Turkey. Individual cyst isolates (n = 60) were collected from infected cattle lungs after slaughter and then samples were stored in ethanol (70%) until further use. From each isolate, total gDNA was extracted from the cysts’ germinal layers. A partial (875 bp) mt-CO1 gene was amplified by PCR and sequenced unidirectionally. The final size of the trimmed sequences was 530 bp for 60 sequences. Sequence and haplotype analyses were performed, followed by phylogenetic analyses. According to BLAST searches, all sequences were detected as E. granulosus s.s. (G1 and G3 strains). Forty-nine point mutations were identified. In addition, five conserved fragments were detected in all sequences. The haplotype analysis diagram showed E. granulosus s.s. haplotypes organized in a star-like configuration. The haplotypes were characterized by 1–17 mutations compared with the fundamental focal haplotype. Thirty-three haplotypes were determined in 60 samples of which 17 (28.3%) belonged to the main haplotype (Hap_06). The mt-CO1 sequences revealed 49 polymorphic sites, 34.5% (20/49) of which were informative according to parsimony analysis.

Echinococcus granulosus sensu lato Genotypes in Different Hosts Worldwide: A Systematic Review

INTRODUCTION

The aim of this study was to develop a synthesis of the evidence available regarding verified E. granulosus sensu lato (s.l.) genotypes in different species worldwide.

MATERIAL AND METHODS

A systematic review was performed including studies concerning genotypes of E. granulosus s.l. without language or genotyped method restriction, published between 1990 and 2020. A systematic search was carried out in Trip Database, BIREME, SciELO, LILACS, IBECS, PAHO-WHO, EMBASE, PubMed, Scopus, and WoS. Variables of interest were year of publication, country, number of samples, and hosts; genotypes, molecular marker, haplotypes and molecular biology techniques used. Descriptive statistics were applied.

RESULTS

2411 articles were analyzed, however 135 met the selection criteria, representing 8643 liver and lung samples. Of the samples selected 24% were human, the remaining samples pertained to non-human animal hosts; cattle and sheep prevailed with 28.6% and 26.6% of the studied samples, respectively. The reported evidence is mainly from Iran, Turkey, Argentina, China and Chile; with 50, 11, 6, 6 and 5 studies, respectively, published between 1992 and 2020 [most frequently during 2015-2020 (76/135 studies; 56.3%)]. The mitochondrial gene cox1 was generally sequenced and informative (91.8%). Genotypes most frequently identified were E. granulosus sensu stricto (s.s.) (83.2%).

CONCLUSIONS

Based on this overall evidence, it can be concluded that publications related to genotypes of E. granulosus s.l. are heterogeneous. E. granulosus ss accounts for the vast majority of the global burden of E. granulosus s.l. worldwide. Further studies including larger number of cases and adequate internal validity are required to specify the distribution of genotypes in various host species.

TRIAL REGISTRATION

PROSPERO CRD42018099827.

Molecular Characterization and Haplotype Analyses of Lung Hydatid Cyst Isolates of Cattle and First Report of Echinococcus canadensis (G6/G7) in Cattle Isolates in Turkey

PURPOSE

Cystic echinococcosis (CE) is a zoonotic disease, caused by parasite known as Echinococcus granulosus sensu lato complex, leading to substantial economic losses in rural areas with public health problems. This study was carried out to understand the haplotypic profiles of the partial mitochondrial cytochrome c oxidase (mt-CO1) gene of cattle lung hydatid cyst samples which were obtained from two provinces in Turkey.

METHODS

In this study, forty (n = 40) hydatid cyst samples from the lungs of slaughtered cattle were obtained. The germinal layers were taken separately for each individual cyst then stored in 70% ethanol. From each individual cyst sample, total genomic DNA was extracted. Amplification of the partial mt-CO1 gene (875 bp) was performed using a specific primer set by PCR, and then, the amplicons were sequenced. All sequences were analyzed individually, followed by alignment, and haplotype and phylogenetic analyses were then performed.

RESULTS

By the sequence alignment process, 39 out of the 40 sequences were characterized as E. granulosus sensu stricto. However, one of them was matched with E. canadensis (G6/G7). The haplotype analyses of the E. granulosus s.s. isolates were arranged in a star-like orientation with a main haplotype, which was separated from other haplotypes by 1-10 mutation steps, and 26 haplotypes were identified. In the mt-CO1 sequences, 29 polymorphic sites were determined, and 34.5% (10/29) of them were parsimony informative.

CONCLUSIONS

The findings of this study provide the first report of E. canadensis (G6/G7 genotype) among cattle in Turkey.

Genetic diversity and haplotypes of paediatric hydatid cyst isolates and first occurrence of E. canadensis (G6/G7) in paediatric cases in Turkey

Cystic echinococcosis (CE) is a neglected zoonotic tropical disease caused by Echinococcus granulosus sensu lato. The aim of this study was to investigate the genetic variation of hydatid cyst isolates obtained from surgically confirmed paediatric cases originating from two different regions in eastern Turkey. Seventeen paediatric cases aged between 6 and 16 were operated by open surgery, and the germinal layers of their cysts were obtained for further molecular analyses. After genomic DNA isolation, 875 bp mt-CO1 gene fragments were amplified in all samples by PCR. Then, the unidirectional sequence analyses of the PCR products were carried out. According to the BLAST analyses of 17 sequences, 16 of these sequences were matched with E. granulosus sensu stricto, while one sequence was identified as E. canadensis (G6/G7) for the first time in paediatric cases in Turkey. High haplotype diversity and low nucleotide diversity were observed in the E. granulosus s.s. sequences.

The situation of echinococcosis in stray dogs in Turkey: the first finding of Echinococcus multilocularis and Echinococcus ortleppi

Echinococcosis, caused by larval stage of the genus Echinococcus, is one of the most important zoonotic diseases worldwide. The purpose of this study was to determine the presence and prevalence of Echinococcus species in stray dogs of Erzurum, a highly endemic region for cystic echinococcosis (CE) and alveolar echinococcosis (AE) in Turkey. The study samples consisted of 446 stray dog faecal specimens collected from an animal shelter in Erzurum, Turkey, between October 2015 and February 2016. The faecal samples were collected from individual dogs for the isolation of taeniid eggs using the sequential sieving and flotation method (SSFM). Molecular analyses and sequencing revealed the prevalence of Echinococcus spp. as 14.13% (63/446) in faecal samples. The stray dogs harboured five different Echinococcus spp.: E. granulosus s.s. (G1/G3) (n = 41), E. equinus (G4) (n = 3), E. ortleppi (G5) (n = 1), E. canadensis (G6/G7) (n = 3) and E. multilocularis (n = 16). E. granulosus s.s. was the most abundant species. Surprisingly, the occurrence of E. multilocularis in dogs was revealed for the first time in Turkey. E. ortleppi was also reported for the first time in Turkey. These findings highlight a significant public health risk for human AE and CE, presenting useful baseline data on Echinococcus spp. infection in dogs for designing control strategies.

Echinococcoses in Iran, Turkey, and Pakistan: Old Diseases in the New Millennium

Echinococcosis is considered a cosmopolitan zoonosis caused by different species of small taeniid tapeworms of the genus Echinococcus and is regarded as a neglected zoonosis. Cystic and alveolar echinococcoses are endemic diseases of Tibetan, Pamir, and Iranian plateaus. All of the countries within the Iranian plateau are affected by echinococcosis. Pakistan, Turkey, and Iran are the three most populous countries of the region, in which echinococcosis is highly endemic. The three neighboring countries share strong cultural and socioeconomic ties. The present study aimed to provide a broad review of the status of cystic and alveolar echinococcosis, summarizing the current knowledge about geographical distribution, molecular epidemiology, and transmission dynamics of Echinococcus granulosus sensu lato and Echinococcus multilocularis in this region. Additionally, we aimed to understand disease burden and risk factors as basic requirements for establishing a surveillance system and planning prevention and control programs. A considerable body of information is available on different aspects of echinococcosis in this region; however, several information and research gaps need to be filled before planning control programs. None of the countries in the region have an elaborate echinococcosis control program. Effective control programs require multi/intersectoral coordination within a One Health approach with a long-term political and administrative commitment and enhanced international collaboration among the three countries.