Cystic echinococcosis in donkeys in eastern Africa.

Cystic echinococcosis (CE) is endemic in humans and domestic animals in eastern Africa. All the species of the Echinococcus granulosus sensu lato complex have been reported in this region except for E. equinus, possibly due to the small number of studies involving equids. This study reports the frequency of different Echinococcus species in donkeys from eastern Africa. A total of 5961 donkeys were examined during meat inspection in 3 slaughterhouses in Kenya. Identification of Echinococcus spp. was achieved through polymerase chain reaction-restriction fragment-length polymorphism and sequencing of the mitochondrial nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 1 gene. The prevalence of CE was 5.7% (337/5961). The 263 genotyped cysts belonged to E. equinus (n = 163), E. granulosus sensu stricto (n = 70), E. canadensis (G6/7) (n = 26) and E. ortleppi (n = 4). One donkey harboured a metacestode of Spirometra theileri. All E. equinus cases, except 2, originated from southern Ethiopia, whereas the other species were more evenly distributed across the study area. Most of the cysts belonging to E. equinus were fertile (111/163), while those of the other species were non-fertile. This is the first report of Echinococcus spp. in donkeys from sub-Saharan Africa and the first confirmation of E. equinus in East Africa. The frequent fertility of E. equinus cysts in donkeys affirms their suitability as intermediate hosts of this species, while low frequency and cyst fertility suggest a marginal role of donkeys in the transmission of E. granulosus s. s., E. canadensis (G6/7) and E. ortleppi.

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.

Human and animal cystic echinococcosis in Konya, Turkey: molecular identification and the first report of E. equinus from human host in Turkey.

Cystic echinococcosis is a neglected, zoonotic disease in Turkey. The disease is commonly seen in rural areas where the local population is in close contact with livestock and dogs. This research aimed to molecularly identify of hydatid cysts in cattle and human isolates from Konya, Turkey. Following sample collection, direct microscopy was performed. After direct examination, total DNA was extracted, and positive PCR products of cox 1 mitochondrial gene (~ 875 bp) were sequenced. A total of 83 hydatid cysts (cattle n = 57 and human n = 26), 82 were identified as Echinococcus granulosus sensu stricto (G1-G3 genotypes), and one human isolate was characterized as Echinococcus equinus (G4 genotype). Fertility rates of cysts belonging to cattle for liver and lung cysts were 93.3% and 80%, respectively. Out of 26 human originated isolates, 18 (69.2%) of cysts were found to be fertile. To the best of our knowledge, this is the first report of E. equinus from human host in Turkey.

Phylogenetic Characteristics of Echinococcus granulosus Sensu Lato in Uzbekistan.

Echinococcosis occurs mainly in areas with heavy livestock farming, such as Central Asia, America, and Australia. Echinococcus granulosus sensu lato (s.l.) infection causes echinococcosis in intermediate hosts, such as sheep, cattle, goats, camels, and horses. Numerous cases of echinococcosis occur in Uzbekistan as stock farming is a primary industry. Epidemiological and genetic studies of E. granulosus s.l. are very important for mitigating its impact on public health and the economy; however, there are no such studies on E. granulosus s.l. in Uzbekistan. In the present study, to determine which genotypes exist and are transmitted, we isolated Echinococcus sp. from definitive hosts (one isolate each from jackal and dog) and intermediate hosts (52 isolates from humans and 6 isolates from sheep) in Uzbekistan and analyzed the isolates by sequencing 2 mitochondrial DNA components (cox1 and nad1). The results showed that all of isolates except one belonged to the E. granulosus sensu stricto (s.s.) G1 and G3 genotypes. Phylogenetic analysis based on cox1 sequences showed that 42 isolates from humans, 6 isolates from sheep, and one isolate from jackal were the G1 genotype, whereas the remaining 8 isolates from human and the one isolate from dog were the G3 genotype. These results suggest that the G1 and G3 genotypes of E. granulosus s.s. are predominant in Uzbekistan, and both wild animals and domestic animals are important for maintaining their life cycle. Only one isolate from human sample was confirmed to be E. eqiinus (G4 genotype), which is known to be for the first time.

Ecology and Life Cycle Patterns of Echinococcus Species.

The genus Echinococcus is composed of eight generally recognized species and one genotypic cluster (Echinococcus canadensis cluster) that may in future be resolved into one to three species. For each species, we review existing information on transmission routes and life cycles in different geographical contexts and - where available - include basic biological information of parasites and hosts (e.g., susceptibility of host species). While some Echinococcus spp. are transmitted in life cycles that involve predominantly domestic animals (e.g., dog - livestock cycles), others are wildlife parasites that do or do not interact with domestic transmission. In many cases, life cycle patterns of the same parasite species differ according to geography. Simple life cycles contrast with transmission patterns that are highly complex, involving multihost systems that may include both domestic and wild mammals. Wildlife transmission may be primary or secondary, i.e., resulting from spillovers from domestic animals. For most of the species and regions, existing information does not yet permit a conclusive description of transmission systems. Such data, however, would be highly relevant, e.g., for anticipation of geographical changes of the presence and frequency of these parasites in a warming world, or for initiating evidence-based control strategies.

A sylvatic lifecycle of Echinococcus equinus in the Etosha National Park, Namibia.

Various species of Echinococcus have been described in the past from wild mammals of sub-Saharan Africa. However, it is only recently, that a few isolates have become available for molecular identification; therefore, the involvement of wildlife in the lifecycles of the various cryptic species within Echinococcus granulosus sensu lato is still only partially known. A preliminary survey was undertaken in Etosha National Park, Namibia, from August to October 2012. Faecal samples were obtained from 34 individual wild carnivores, and metacestodes were collected from carcasses of 18 culled herbivores. Single eggs and metacestode tissue were lysed and identified from sequences of the mitochondrial nad1 gene. In case of metacestodes, the cox1 gene was additionally sequenced and haplotype networks were constructed. Echinococcus equinus was found in lions (4 of 6), black-backed jackals (2 of 7) and Burchell's zebras (11 of 12). The frequency of this parasite in the absence of domestic dogs, horses and donkeys strongly indicates its transmission in a wildlife cycle. Further, a variety of sequences were obtained from eggs and cysticerci from lions, cheetahs, caracals, spotted hyenas and oryx, which most closely clustered with species of Taenia. Only 3 of them, 2 of lion and 1 of hyena origin, could be allocated to Hydatigera (=Taenia) taeniaeformis (lion), Taenia regis (lions and oryx) and Taenia cf. crocutae (spotted hyena and oryx).

Echinococcus equinus and Echinococcus granulosus sensu stricto from the United Kingdom: genetic diversity and haplotypic variation.

Cystic echinococcosis is endemic in Europe including the United Kingdom. However, information on the molecular epidemiology of Echinococcus spp. from the United Kingdom is limited. Echinococcus isolates from intermediate and definitive animal hosts as well as from human cystic echinococcosis cases were analysed to determine species and genotypes within these hosts. Echinococcus equinus was identified from horse hydatid isolates, cysts retrieved from captive UK mammals and copro-DNA of foxhounds and farm dogs. Echinococcus granulosus sensu stricto (s.s.) was identified from hydatid cysts of sheep and cattle as well as in DNA extracted from farm dog and foxhound faecal samples, and from four human cystic echinococcosis isolates, including the first known molecular confirmation of E. granulosus s.s. infection in a Welsh sheep farmer. Low genetic variability for E. equinus from various hosts and from different geographical locations was detected using the mitochondrial cytochrome c oxidase subunit 1 gene (cox1), indicating the presence of a dominant haplotype (EQUK01). In contrast, greater haplotypic variation was observed for E. granulosus s.s. cox1 sequences. The haplotype network showed a star-shaped network with a centrally placed main haplotype (EgUK01) that had been reported from other world regions.

First Report of Echinococcus equinus in a Donkey in Turkey.

A 2-year-old female donkey (Equus asinus) was euthanized in the Pathology Department of Firat University, Elazig, Turkey. Necropsy disclosed the presence of 7 hydatid cysts distributed throughout the lung parenchyma. One of those cysts represented the parasite material of the present study and was molecularly identified through sequencing of a fragment of cytochrome c oxidase subunit 1 (CO1) and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (NADH1) gene, as Echinococcus equinus. The generated CO1 sequence supports the presence of the dominant haplotype as has been described in Europe and Africa. The NADH1 sequence was found similar to sequences reported in equids in Egypt and the United Kingdom. The molecular identification of E. equinus in a donkey is being reported for the first time in Turkey.

First Report of Echinococcus equinus in a Donkey in Turkey

A 2-year-old female donkey (Equus asinus) was euthanized in the Pathology Department of Firat University, Elazig, Turkey. Necropsy disclosed the presence of 7 hydatid cysts distributed throughout the lung parenchyma. One of those cysts represented the parasite material of the present study and was molecularly identified through sequencing of a fragment of cytochrome c oxidase subunit 1 (CO1) and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (NADH1) gene, as Echinococcus equinus. The generated CO1 sequence supports the presence of the dominant haplotype as has been described in Europe and Africa. The NADH1 sequence was found similar to sequences reported in equids in Egypt and the United Kingdom. The molecular identification of E. equinus in a donkey is being reported for the first time in Turkey.

Genetic variability and haplotypes of Echinococcus isolates from Tunisia.

BACKGROUND: The species/genotypes of Echinococcus infecting a range of intermediate, canid and human hosts were examined as well as the intraspecific variation and population structure of Echinococcus granulosus sensu lato (s.l.) within these hosts. METHODS: A total of 174 Echinococcus isolates from humans and ungulate intermediate hosts and adult tapeworms from dogs and jackals were used. Genomic DNA was used to amplify a fragment within a mitochondrial gene and a nuclear gene, coding for cytochrome c oxidase subunit 1 (cox1; 828 bp) and elongation factor 1-alpha (ef1a; 656 bp), respectively. RESULTS: E. granulosus sensu stricto was identified from all host species examined, E. canadensis (G6) in a camel and, for the first time, fertile cysts of E. granulosus (s.s.) and E. equinus in equids (donkeys) and E. granulosus (s.s.) from wild boars and goats. Considerable genetic variation was seen only for the cox1 sequences of E. granulosus (s.s.). The pairwise fixation index (Fst) for cox1 E. granulosus (s.s.) sequences from donkeys was high and was statistically significant compared with that of E. granulosus populations from other intermediate hosts. A single haplotype (EqTu01) was identified for the cox1 nucleotide sequences of E. equinus. CONCLUSIONS: The role of donkeys in the epidemiology of echinococcosis in Tunisia requires further investigation.