Echinostoma hortense (Digenea: Echinostomatidae) is one of the intestinal flukes with medical importance in humans. However, the mitochondrial (mt) genome of this fluke has not been known yet. The present study has determined the complete mt genome sequences of E. hortense and assessed the phylogenetic relationships with other digenean species for which the complete mt genome sequences are available in GenBank using concatenated amino acid sequences inferred from 12 protein-coding genes. The mt genome of E. hortense contained 12 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 non-coding region. The length of the mt genome of E. hortense was 14,994 bp, which was somewhat smaller than those of other trematode species. Phylogenetic analyses based on concatenated nucleotide sequence datasets for all 12 protein-coding genes using maximum parsimony (MP) method showed that E. hortense and Hypoderaeum conoideum gathered together, and they were closer to each other than to Fasciolidae and other echinostomatid trematodes. The availability of the complete mt genome sequences of E. hortense provides important genetic markers for diagnostics, population genetics, and evolutionary studies of digeneans.
Amino Acid Sequence ; Base Sequence ; Databases, Nucleic Acid ; Dataset ; Echinostoma* ; Echinostomatidae ; Fasciolidae ; Genes, rRNA ; Genetic Markers ; Genetics, Population ; Genome ; Genome, Mitochondrial* ; Humans ; RNA, Transfer ; Trematoda

The present study was performed to observe tegumental ultrastructure of Echinoparyphium recurvatum according to developmental stages. Worms (1, 3, 5 and 15-day old) were recovered from chicks experimentally infected with metacercariae from Radix auricularia coreana. One-day old worms were elongated and ventrally concave, and covered with peg-like tegumental spines except the adjecent areas of the head crown and excretory pore. Type I sensory papillae were distributed on the lip of the oral sucker, and grouped ciliated papillae were around the oral sucker. Peg-like tegumental spines were densely distributed on the anterior surface of the ventral sucker level. The ventral sucker had an aspinous tegument and no sensory papillae. Tegumental spines on the posterior surface of the ventral sucker level were sparsely distributed and disappeared posteriorly. In 3 and 5-day old worms, the tegument around the oral sucker was aspinose and wrinkled concentrically. The ventral sucker had a wrinkled tegument and many bulbous papillae. Type I sensory papillae were distributed between the bulbous papillae. Tegumental spines were spade-shaped with a terminal tip. A total of 45 collar spines including 4 end group ones on both ventral corners was alternately arranged in 2 rows. The 15-day old worms were very stout and their tegumental spines were tongue-shaped without a terminal tip. From the above results, it is confirmed that the surface ultrastructure of E. recurvatum was generally similar to that of other echinostomatid flukes. However, some features, i.e., morphological change of tegumental spines and appearence of sensory papillae on the ventral sucker according to development, and number, shape and arrangement of collar spines, were characteristic, which may be of taxonomic and bioecological significance.
Animals ; Chickens ; Echinostomatidae/anatomy & histology/growth & development/*ultrastructure ; Life Cycle Stages ; Lymnaea/parasitology ; Microscopy, Electron, Scanning

Metacercariae of Acanthoparyphium marilae Yamaguti, 1934 (Digenea: Echinostomatidae) were discovered in an intertidal clam, Mactra veneriformis, in a southwestern coastal area of the Republic of Korea. A total of 128 metacercariae were detected from 10 clams examined. They were round, 320 m in average diameter, with 23 collar spines. They were fed experimentally to chicks, and 10 days later adult flukes were obtained. The adults were morphologically characterized by the head collar with a single row of 23 dorsally uninterrupted spines, without special end group spines, a round ventral sucker, 2 round and tandem testes, and vitellaria extending at lateral fields from the posterior extremity not beyond the middle level of the posterior testis. The most characteristic feature of this species was the limited distribution of vitellaria, which differs from Acanthoparyphium tyosenense Yamaguti, 1939, the metacercariae of which are encysted in the same mollusk species. This is the first report in which the metacercariae of this species were detected, and the intertidal bivalve, M. veneriformis, has been identified as a second intermediate host for A. marilae.
Animals ; Bivalvia/*parasitology ; Chickens ; Echinostomatidae/anatomy & histology/cytology/*isolation & purification ; *Host-Parasite Interactions ; Korea ; Trematode Infections/parasitology/veterinary

Freshwater snails, as the first intermediate hosts of trematodes, can cause health hazards in animals and humans. Recently, the World Health Organization has included Iran in a list of 6 countries known to have serious problems with fascioliasis. In addition, cercarial dermatitis is a job-related disease that is seen often in paddy workers, agricultural labourers, and fishermen in Iran, particularly in Mazandaran Province. Many studies have been conducted in Iran to survey larval trematodes in freshwater snails. However, to the best of our knowledge, no comprehensive data exist regarding infections in gastropods. Therefore, the aim of the present study was to estimate the types and prevalence of cercarial infections in snails in Iran. Electronic English-language and Persian-language databases were searched to identify 24 published articles reporting the prevalence of trematode infections in snails (9 species from 6 families) in various provinces of Iran. In total, 4.4% of gastropods were infected with the larval stages of trematodes. According to the studies reviewed in this meta-analysis‚ the highest infection prevalence was found in Radix auricularia (9.9%). Twelve larval species of trematodes were identified, and the highest prevalence of cercariae was found for Echinostomatidae cercariae (4.3%). Among the provinces explored, West Azerbaijan had the highest prevalence of infected snails (16.9%). The presence of trematodes in snails could pose a serious health problem in Iran. Thus, further studies are necessary to characterize these infections in other provinces.
Animals ; Azerbaijan ; Cercaria ; Dermatitis ; Echinostomatidae ; Farmers ; Fascioliasis ; Fresh Water ; Gastropoda ; Humans ; Iran ; Prevalence ; Snails ; Trematode Infections ; World Health Organization

Freshwater snails, as the first intermediate hosts of trematodes, can cause health hazards in animals and humans. Recently, the World Health Organization has included Iran in a list of 6 countries known to have serious problems with fascioliasis. In addition, cercarial dermatitis is a job-related disease that is seen often in paddy workers, agricultural labourers, and fishermen in Iran, particularly in Mazandaran Province. Many studies have been conducted in Iran to survey larval trematodes in freshwater snails. However, to the best of our knowledge, no comprehensive data exist regarding infections in gastropods. Therefore, the aim of the present study was to estimate the types and prevalence of cercarial infections in snails in Iran. Electronic English-language and Persian-language databases were searched to identify 24 published articles reporting the prevalence of trematode infections in snails (9 species from 6 families) in various provinces of Iran. In total, 4.4% of gastropods were infected with the larval stages of trematodes. According to the studies reviewed in this meta-analysis‚ the highest infection prevalence was found in Radix auricularia (9.9%). Twelve larval species of trematodes were identified, and the highest prevalence of cercariae was found for Echinostomatidae cercariae (4.3%). Among the provinces explored, West Azerbaijan had the highest prevalence of infected snails (16.9%). The presence of trematodes in snails could pose a serious health problem in Iran. Thus, further studies are necessary to characterize these infections in other provinces.
Animals ; Azerbaijan ; Cercaria ; Dermatitis ; Echinostomatidae ; Farmers ; Fascioliasis ; Fresh Water ; Gastropoda ; Humans ; Iran ; Prevalence ; Snails ; Trematode Infections ; World Health Organization

Echinostome eggs were detected in 22 (1.1%) of 2,074 people residing in riparian villages along the Mekong River in Khammouane Province, Lao PDR. In order to recover the adult flukes, 9 persons were treated with praziquantel and purged with magnesium salts. A total of 55 echinostome specimens (4 species) were recovered from the 9 persons. Echinostoma revolutum (8 specimens) was recovered from 3 persons, Artyfechinostomum malayanum (8 specimens) was from 2 persons, Echinochasmus japonicus (33 specimens) was from 7 persons, and Euparyphium sp. (6 specimens) was from 1 person. In Lao PDR, only human infections with E. japonicus were previously known. Therefore, the present study describes human infections with E. revolutum, A. malayanum, and Euparyphium sp. for the first time in Lao PDR. These results indicate that the surveyed villages of Khammouane Province, Lao PDR are low-grade endemic foci of echinostomiasis.
Adult ; Animals ; Anthelmintics/administration & dosage ; Echinostomatidae/*classification/*isolation & purification ; Female ; Humans ; Laos ; Magnesium/administration & dosage ; Male ; Praziquantel/administration & dosage ; Trematode Infections/*parasitology

Free-grazing ducks play a major role in the rural economy of Eastern Asia in the form of egg and meat production. In Thailand, the geographical location, tropical climate conditions and wetland areas of the country are suitable for their husbandry. These environmental factors also favor growth, multiplication, development, survival, and spread of duck parasites. In this study, a total of 90 free-grazing ducks from northern, central, and northeastern regions of Thailand were examined for intestinal helminth parasites, with special emphasis on zoonotic echinostomes. Of these, 51 (56.7%) were infected by one or more species of zoonotic echinostomes, Echinostoma revolutum, Echinoparyphium recurvatum, and Hypoderaeum conoideum. Echinostomes found were identified using morphological criteria when possible. ITS2 sequences were used to identify juvenile and incomplete worms. The prevalence of infection was relatively high in each region, namely, north, central, and northeast region was 63.2%, 54.5%, and 55.3%, respectively. The intensity of infection ranged up to 49 worms/infected duck. Free-grazing ducks clearly play an important role in the life cycle maintenance, spread, and transmission of these medically important echinostomes in Thailand.
Animals ; Bird Diseases/*epidemiology/*parasitology ; DNA, Ribosomal Spacer/chemistry/genetics ; Ducks/*parasitology ; Echinostomatidae/anatomy & histology/classification/genetics/*isolation & purification ; Helminthiasis/epidemiology/parasitology ; Intestinal Diseases/epidemiology/parasitology/*veterinary ; Microscopy ; Prevalence ; Sequence Analysis, DNA ; Thailand ; Trematode Infections/epidemiology/parasitology/*veterinary

Authors carried out an investigation of the helminthic parasites of the wild birds in Korea. Most wild birds were collected from Kyoung Sang Do, Kyoung Kee Do and Seoul area from September 1970 to March 1973. A total of 70 wild birds, 19 species were examined, which comprised as follows; 10 Anas platyrhynchus, 10 Anas fulicata, 4 Anas poeciolorhyncha zonorhyncha, 8 Anser albifrone albifrone, 5 Anser cygonopsis cygnoid, 10 Aythya fuligula, 6 Gallicrex cinerea, 2 Porgana fusca, 2 Phisianum calichius korponri, 4 Sterptopilla orientalis, Podiceps cristatus, Larus crasirotatus, Malantta fusca, Garis artcus, Buetes buteo, Egretta alba, Starmus philpiens, Bombycilla granulus. Trematode parasites found from six species of the wild birds. Echinostomatidae has been found from intestine of the Anas platyrhynchus platyrhynchus, Anas poeciolorhyncha zonorhyncha, Anas fulcata. Notocatylus attenuatis found from intestine of the Podiceps cristatus, Anas fulcata. Catylurus japonicus was found from rectum of the Anas platyrhynchus platyrhynchus, Anas poeciolorhyncha zonorhyncha.
parasitology-helminth-trematoda ; Notocatylus attenuatus ; Catylurus japonicus ; Echinostoma revolutum ; Echinostoma gotoi ; Echinostoma miyagawai ; Echinoparyphium koizumi ; bird

The tegumental ultrastructures of Echinostoma hortense adults were observed by scanning electron microscopy. The worms of 4 weeks of age were harvested from albino rats experimentally infected with the metacercariae obtained from the loach. The results were as follows: The worms were leaf-like and their anterior end portion, including oral sucker and head crown, ventrally curved to face posteriorly. The tegument of whole body was wrinkled transversely and covered with cobblestone-like cytoplasmic processes. The oral sucker had roundly swollen (type II) sensory papillae on the ventral half of its lip and uni-ciliated knob-like (type I) sensory papillae, arranged in 2-3 rows, on the dorsal outer surface. Aspinous ventral sucker had many of type I papillae arranged in a circular band on its outer surface. The tegument around the genital opening was of similar feature to the ventral sucker, but sensory papillae were hardly found around the former. Scale-like spines with broad base and round tip were distributed densely on the tegument anterior to the ventral sucker but they became sparse in posterior half of the ventral surface, finally to disappear at posterior extremity. A few number of type I papillae were observed on the ventral surface. The results suggest that the tegument of E. hortense is similar to that of other echinostomes especially E. revolutum. But the number and arrangement of collar spines, and/or the type and distribution of sensory papillae seem characteristic features of E. hortense differed from other echinostomes.
parasitology-helminth-trematoda ; Echinostoma hortense ; electron microscopy

Echinostomatid eggs were found from a 21-year old man, whole native village is Munkyong-gun, Kyongsangnam-do during fecal examination in October 1983. The eggs were detected again one week later concommitantly with the eggs of Clonorchis sinensis. He had no subjective symptoms related with these fluke infections. He was treated with praziquantel(Distocide) 20 mg/kg in single dose and purgated with magnesium salt. One echinostomatid fluke and 4 adults of C. sinensis were collected from the diarrheal stools. After morphological observation, the echinostomatid fluke was identified as Echinostoma hortense Asada, 1926. This is the first record on human E. hortense infection in Korea.
parasitology-helminth-trematoda ; Echinostoma hortense ; case report ; echinostomiasis ; praziquantel