The heterophyid trematode Metagonimus romanicus (Ciurea, 1915) (Digenea) is redescribed on the basis of type material from domestic dogs (Canis familiaris) in Romania, vouchers from experimentally infected cats (Felis catus) and adults recovered from golden hamsters (Mesocricetus auratus) infected with metacercariae from scales of chub (Squalius cephalus) and common nase (Chondrostoma nasus) (Cypriniformes: Leuciscidae) in Hungary. This trematode, endemic to Europe and neighbouring regions (northwestern Türkiye), was previously misidentified as M. yokogawai (Katsurada, 1912), a zoonotic parasite of humans in East Asia. However, the two species differ considerably both genetically and morphologically, e.g., in the position of the ventral sucker, the presence of the prepharynx, the anterior extent of the vitelline follicles and the posterior extent of the uterus. Metagonimus ciureanus (Witenberg, 1929) (syn. Dexiogonimus ciureanus Witenberg, 1929), described from domestic cats and dogs in Israel, is a valid species distributed in the Middle East and Transcaucasia, which is also confirmed by molecular data. It differs from all Metagonimus species, including M. romanicus, in having symmetrical testes instead of the oblique testes of the other congeners. The zoonotic significance of M. romanicus and M. ciureanus is unclear, but appears to be low in Europe, mainly because raw or undercooked, whole fish with scales are generally not consumed. Accidental infection of fishermen by metacercariae in the scales when cleaning fish is more likely, but has never been reported. Remains of cyprinoids with scales infected with metacercariae of Metagonimus spp. can be an important natural source of infection for dogs, cats, and other carnivores, which can serve as a reservoir for these parasites.

TITLE: Petits trématodes intestinaux du genre Metagonimus (Digenea : Heterophyidae) en Europe et au Moyen-Orient : revue de parasites à potentiel zoonotique. ABSTRACT: Le trématode Heterophyidae Metagonimus romanicus (Ciurea, 1915) (Digenea) est redécrit sur la base de matériel type provenant de chiens domestiques (Canis familiaris) en Roumanie, de vouchers issus de chats (Felis catus) infectés expérimentalement et d’adultes collectés chez des hamsters dorés (Mesocricetus auratus) infectés par des métacercaires provenant d’écailles de chevesne commun (Squalius cephalus) et de nase commun (Chondrostoma nasus) (Cypriniformes : Leuciscidae) de Hongrie. Ce trématode, endémique d’Europe et des régions voisines (nord-ouest de la Turquie), avait été précédemment identifié à tort comme étant M. yokogawai (Katsurada, 1912), un parasite zoonotique des humains en Asie de l’Est. Cependant, les deux espèces diffèrent considérablement sur le plan génétique et morphologique, par exemple par la position de la ventouse ventrale, la présence du prépharynx, l’étendue antérieure des follicules vitellins et l’étendue postérieure de l’utérus. Metagonimus ciureanus (Witenberg, 1929) (syn. Dexiogonimus ciureanus Witenberg, 1929), décrite chez des chats et des chiens domestiques en Israël, est une espèce valide répartie au Moyen-Orient et en Transcaucasie, ce qui est également confirmé par des données moléculaires. Cette espèce diffère de toutes les espèces de Metagonimus, y compris M. romanicus, par ses testicules symétriques au lieu des testicules obliques des autres congénères. L’importance zoonotique de M. romanicus et M. ciureanus n’est pas claire, mais semble faible en Europe, principalement parce que les poissons n’y sont généralement pas consommés crus ou insuffisamment cuits et entiers avec les écailles. L’infection accidentelle des pêcheurs par des métacercaires présents dans les écailles lors du nettoyage du poisson est plus probable mais n’a jamais été signalée. Les restes de poissons cyprinoïdes avec les écailles, infectés par des métacercaires de Metagonimus spp. peuvent être une source naturelle importante d’infection pour les chiens, les chats et autres carnivores, qui peuvent servir de réservoir à ces parasites.

• Klíčová slova
• Fish-borne zoonoses, Genotyping, Palaearctic region, Redescription, SEM, Taxonomy, Trematoda,
• MeSH
• Cyprinidae * MeSH
• Heterophyidae * anatomie a histologie   MeSH
• infekce červy třídy Trematoda * epidemiologie   veterinární   parazitologie   MeSH
• kočky MeSH
• křeček rodu Mesocricetus MeSH
• lidé MeSH
• metacerkárie MeSH
• paraziti * MeSH
• psi MeSH
• Trematoda * MeSH
• zvířata MeSH
• Check Tag
• kočky MeSH
• lidé MeSH
• psi MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Geografické názvy
• Evropa epidemiologie   MeSH
• Střední východ epidemiologie   MeSH

Metagonimus Katsurada, 1912 is a genus of small intestinal parasites. The genus comprises eight species, primarily from far-eastern Asia, with two exceptions reported from Europe. Metagonimus yokogawai, the most widespread species, is the main agent responsible for the intestinal disease, metagonimiasis, in Japan and some other East Asian countries. On the basis of the ratio of the size of the ventral and oral suckers, Metagonimus has traditionally been morphologically divided into two groups; however, the genus has not been extensively studied using molecular data. To reveal phylogenetic relationships within Metagonimus based on molecular data, we analyzed six of the seven species present in Asia using samples collected in central Japan. Maximum likelihood and Bayesian analyses of a combined 28S ribosomal DNA (rDNA), internal transcribed spacer 2 (ITS2), and mitochondrial cox1 gene sequence dataset separated the six species into two well-supported clades. One clade comprised M. yokogawai, M. takahashii, M. miyatai, and M. hakubaensis, whereas the other consisted of M. otsurui and M. katsuradai. Genetic distances calculated from 28S rDNA and ITS2 nucleotide sequences and a comparison of the predicted amino acid sequences of cox1 gene suggested that M. otsurui and M. katsuradai may have diverged recently. None of the four main morphological characters used to delimit species of Metagonimus (i.e., sucker ratio, positions of the uterus and testes, and distribution of vitelline follicles) was consistent with the distribution of species in the molecular tree.

• Klíčová slova
• 28S rDNA, ITS2, Incongruence, Interrelations, Metagonimus, Morphology, cox1,
• MeSH
• druhová specificita MeSH
• fylogeneze * MeSH
• Heterophyidae klasifikace   genetika   MeSH
• mezerníky ribozomální DNA genetika   MeSH
• respirační komplex IV genetika   MeSH
• RNA ribozomální 28S genetika   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Japonsko MeSH
• Názvy látek
• mezerníky ribozomální DNA MeSH
• respirační komplex IV MeSH
• RNA ribozomální 28S MeSH

Species of Ascocotyle Looss, 1899 (subgenus Phagicola Faust, 1920) (Digenea: Heterophyidae) related to A. (P.) longa Ransom, 1920, i.e. those with a bipartite gonotyl and a single crown of 16 circumoral spines, were revised on the basis of examination of type and voucher specimens. The species A. (P.) arnaldoi Travassos, 1929, A. (P.) byrdi (Robinson, 1956) and A. (P.) longicollis (Kuntz & Chandler, 1956), all possessing 16 circumoral spines, are synonymised with A. (P.) longa. A. (P.) ascolonga Witenberg, 1929, the types of which were not available, is provisionally retained as a valid species despite its close similarity to A. (P.) longa (identical number of circumoral spines and morphology of the ventrogenital sac). It differs from A. (P.) longa in the presence of uterine loops posterior to the testes and intestinal caeca ending anterior to the ovary (versus the pretesticular uterus and intestinal caeca reaching to the posterior margin of the ovary in A. (P.) longa). A. (P.) inglei (Hutton & Sogandares-Bernal, 1959), found only once in a single specimen, is also tentatively considered a valid species because it differs in number of circumoral spines (19), slightly larger eggs (23-26 x 13-16 microns) and the distribution of refractile bodies of the gonotyl arranged in four separate groups from A. (P.) longa and A. (P.) ascolonga (16 circumoral spines; eggs 15-20 x 8-12 microns; refractile bodies in two groups).

• MeSH
• Heterophyidae anatomie a histologie   klasifikace   MeSH
• kočky parazitologie   MeSH
• Perciformes parazitologie   MeSH
• psi parazitologie   MeSH
• ptáci parazitologie   MeSH
• zvířata MeSH
• Check Tag
• kočky parazitologie   MeSH
• mužské pohlaví MeSH
• psi parazitologie   MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Phagicola pithecophagicola Faust, 1920, the type species of Phagicola Faust, 1920 (Trematoda: Heterophyidae: Phagicolinae), is redescribed on the basis of examination of type specimens (syntypes) from the monkey-eating eagle, Pithecophaga jeffreyi, from the Philippines. The oral sucker is armed with 1 complete row of 16 circumoral spines (10-19.5 microns long by 4-8 microns wide) and 4 accessory spines (5.5-8 microns long by 3-4 microns wide) on the dorsal side; this arrangement differs from the original description and later redescriptions, where only 12 circumoral spines in 1 row were reported. The ventrogenital sac contains a ventral sucker and a large gonotyl with 2 small, often indistinct, lobes containing a few refractile bodies. The intestinal ceca extend reaching down to the ovarian level. The uterus is confined to the acetabulo-ovarian region, and eggs are 17-20 microns long by 9-10 microns wide.

• MeSH
• Heterophyidae anatomie a histologie   klasifikace   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The egg morphology of the following medically important small flukes from Southeast Asia and Far East were studied: Opisthorchis viverrini, Clonorchis sinensis (Opisthorchiidae), Haplorchis taichui, H. pumilio, H. yokogawai, Stellantchasmus falcatus and Metagonimus sp. (Heterophydiae). This study revealed a great intraspecific variability and interspecific similarity in size and shape of eggs. The eggs shape does not seem to be suitable for species identification. On the other hand, biometrical analysis of egg size enabled us to divide eggs from the species studied into four distinct groups according to the Faust-Meleney index (FMI) characterizing egg size rather than the length and width of eggs. The surface structures of eggs, delineated by using a scanning electron microscope (SEM), appeared to be a suitable morphological feature for distinguishing some groups of small flukes. Eggs from the Haplorchiinae were typified by the characteristic filamentous mesh structure. The problems of identification of eggs in human stool samples and suitability of using morphological criteria such as shape and size of eggs are discussed herein.

• MeSH
• Heterophyidae ultrastruktura   MeSH
• infekce červy třídy Trematoda parazitologie   MeSH
• lidé MeSH
• Opisthorchidae ultrastruktura   MeSH
• ovum ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Geografické názvy
• Dálný východ MeSH
• jihovýchodní Asie MeSH

• MeSH
• Heterophyidae izolace a purifikace   MeSH
• infekce červy třídy Trematoda epidemiologie   parazitologie   MeSH
• lidé MeSH
• prevalence MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Laos epidemiologie   MeSH

Sera from 642 inhabitants of Vientiane Province (Laos) were examined by enzyme-linked immunosorbent assay (ELISA) using cytoplasmic and membranous antigens prepared from adult worms. Worms of Opisthorchis viverrini originated from liver of dissected cats, Haplorchis taichui were obtained from a stool specimen of a Laotian patient after praziquantel treatment. The sera were divided into five groups according to the intensity of infection expressed as egg count per gram of patients stool (EPG). Correlation between intensity of infection and the level of antibodies in serum was recorded. Reactions obtained using the cytoplasmic antigens were more sensitive and more specific compared to those with membranous antigens. Cross-reactions between antigens of both helminth species were found. Highly positive sera were examined using electroimmunotransfer blots (EITB) with cytoplasmic antigens of both species, which enabled the species differentiation. Antigens of both species yielded several shared fractions; however, differences between them were found: homologous sera reacted specifically with O. viverrini antigen in the area of 70 kDa and with H. taichui antigen in the area of 10 kDa. Thirty-one of 122 tested sera had specific antibodies against O. viverrini, 77 sera against H. taichui and 14 sera against both species. The results confirmed our assumption about predominant occurrence of heterophyid flukes in the human population living in studied area, compared with the occurrence of opisthorchid flukes. Hence, serology seems to be helpful tool for correct diagnosis of small fluke infections.

• MeSH
• antigeny helmintové * imunologie   MeSH
• antigeny povrchové imunologie   MeSH
• ELISA MeSH
• Heterophyidae imunologie   MeSH
• imunoblotting MeSH
• infekce červy třídy Trematoda diagnóza   parazitologie   MeSH
• lidé MeSH
• Opisthorchis imunologie   MeSH
• protilátky helmintové krev   MeSH
• senzitivita a specificita MeSH
• zkřížené reakce MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny helmintové * MeSH
• antigeny povrchové MeSH
• protilátky helmintové MeSH

The examination of flesh of 313 cyprinid fish from the Nam Ngum water reservoir in Vientiane Province, Laos, revealed the presence of four morphologically similar opisthorchiid and heterophyid metacercariae of medical importance. The following morphological characters, visible under dissecting microscope with low magnification, were typical of trematodes recorded in fish: (1) Opisthorchis viverrini, the liver fluke, has oval cysts containing quickly moving C-shaped metacercariae provided with a rather large excretory bladder; (2) metacercariae of Haplorchis pumilio and H. taichui are surrounded by a thin-walled, oval cyst; they are actively motile, C- or S-shaped, and possess a relatively small excretory bladder; (3) cysts of Haplorchoides mehrai are considerably variable in shape, size, and thickness of cyst wall; larvae are slowly moving, C- or S-shaped, or often not folded, and provided with a rather small excretory bladder. Some cysts with dead or degenerated H. mehrai larvae are filled with brownish or yellowish pigment. Morphological variability of some larvae, however, excluded correct identification of all metacercariae during routine examination of fish. Therefore, we consider isolation of several larvae from each fish host as well as all "atypical" metacercariae from fish flesh and their examination under the light microscope to be necessary. Even though this method of examination is rather time consuming, it decreases the possibility of false identification of trematode larvae encysted in flesh of cyprinid fish during field studies on opisthorchosis and heterophyiosis.

• MeSH
• diferenciální diagnóza MeSH
• Heterophyidae izolace a purifikace   MeSH
• infekce červy třídy Trematoda parazitologie   veterinární   MeSH
• nemoci ryb parazitologie   MeSH
• Opisthorchidae izolace a purifikace   MeSH
• ryby MeSH
• sladká voda MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Laos MeSH

The morphology of the surface of two heterophyid flukes, Haplorchis yokogawai and H. taichui, that can infect humans eating raw fish flesh, has been studied using scanning and transmission electron microscopy. The body surface of both species is covered with scale-like, serrated spines with the exception of areas around the oral sucker, ventrogenital opening and excretory pore. The species slightly differ by the dentation pattern of tegumental spines: H. yokogawai has finer and more numerous spine teeth (maximum tooth number 14-16) while H. taichui has more serrated spines, mostly with a lower number (up to 10-12) of somewhat more robust teeth. However, because of the variability, the shape and dentation of spines do not seem to be reliable diagnostic features enabling mutual differentiation of both species.

• MeSH
• diferenciální diagnóza MeSH
• Heterophyidae anatomie a histologie   klasifikace   ultrastruktura   MeSH
• hodnotící studie jako téma MeSH
• infekce červy třídy Trematoda diagnóza   etiologie   MeSH
• lidé MeSH
• ryby MeSH
• stravovací zvyklosti MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

A study of the epidemiology of trematode infections was carried out in Vientiane province, Laos, comprising examination of snails, fish, cats, and human stools. Opisthorchis viverrini cercariae were found in the snail Bithynia siamensis goniomphalus (Bithyniidae) and Haplorchis taichui cercariae in Tarebia granifera (Thiaridae). O. viverrini metacercariae were recorded in the flesh of 7 species of cyprinid fish; metacercariae of the heterophyid fluke Haplorchis taichui were found in 4 species of cyprinid fish and those of H. pumilio in 2 species. Cats from the same localities were infected with O. viverrini and 4 species of heterophyid flukes, frequently as multiple infections. The highest prevalence of small fluke eggs in human stools was recorded in the 20-29 years age group, particularly in males (90.4%). Three-quarters of human infections were light (less than 1000 eggs/g), the highest value (2975 eggs/g) being recorded in the 10-14 years age group. Identification of small flukes excreted by Laotian patients after treatment with praziquantel in Czechoslovakia revealed more cases with H. taichui than with O. viverrini. The results confirmed the simultaneous occurrence of O. viverrini and intestinal heterophyid flukes in the area studied.

• MeSH
• dítě MeSH
• dospělí MeSH
• Heterophyidae izolace a purifikace   MeSH
• hlemýždi parazitologie   MeSH
• infekce červy třídy Trematoda epidemiologie   veterinární   MeSH
• infekce přenášené vektorem MeSH
• kočky MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• nemoci koček epidemiologie   MeSH
• nemoci ryb epidemiologie   MeSH
• novorozenec MeSH
• opistorchióza epidemiologie   veterinární   MeSH
• předškolní dítě MeSH
• ryby MeSH
• senioři MeSH
• Trematoda izolace a purifikace   MeSH
• zvířata MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kočky MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• senioři MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Laos epidemiologie   MeSH