Fish-borne zoonoses are emerging worldwide, and although most human cases remain confined to tropical regions, particularly Southeast and East Asia, a few cases have been reported in Europe. This review summarizes published and new data on the life cycle of Metagonimus romanicus (misidentified as M. yokogawai, a human pathogen common in East Asia), a heterophyid trematode and one of the potentially fish-borne parasites in Europe. Metagonimus romanicus is distributed from the middle Danube in Central Europe (Slovakia) to eastern Ukraine (including the rivers of the Black Sea basin). Its distribution area coincides with that of its first intermediate hosts, the melanopsid snails Microcolpia daudebartii acicularis and Esperiana esperi. While M. romanicus most likely has a strict specificity for its first snail hosts, metacercariae are generalists and have been detected in over 50 freshwater fish species from 18 families, especially leuciscids. Despite its wide distribution and frequent occurrence in freshwater fish, the zoonotic potential of M. romanicus appears to be low. This is probably due to the exclusive localization of the metacercariae in the fish scales rather than musculature, as well as the rare consumption of raw or undercooked fish in Europe. However, some risk remains and a small number of undiagnosed human infections due to accidental ingestion of scales during the preparation and cleaning of fish cannot be ruled out.

• Klíčová slova
• Cercariae, Europe, Fish, Freshwater, Metacercariae, Snails,
• Publikační typ
• časopisecké články MeSH

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

Two species of heterophyid trematodes were found in the Magellanic penguin, Spheniscus magellanicus (Forster), from Patagonia, Argentina. Ascocotyle (Ascocotyle) patagoniensis Hernández-Orts et al. (2012) is re-described based on new, properly fixed specimens (original material from South American sea lion, Otaria flavescens Shaw, was from frozen hosts). Metacercariae of this species are reported and described for the first time from the heart of the silversides, Odontesthes argentinensis (Valenciennes) and O. smitti (Lahille), from Patagonia. Ascocotyle (Phagicola) cameliae n. sp. is described from the intestine of S. magellanicus. The new species is placed into the subgenus Phagicola Faust, 1920 because of the presence of a single row of circumoral spines and uterine loops and vitelline follicles being confined posterior to the ventral sucker. However, it differs distinctly from other members of this subgenus by the number (19-24) and length (23-31 μm) of massive circumoral spines and by the morphology of the ventrogenital sac with a large, simple gonotyl devoid of refractile bodies. Molecular data (partial 28S rDNA sequences) for both species are also provided. Matching sequences from metacercarial and adult stages helped elucidate partially the life-cycle of A. (A.) patagoniensis. The interspecific relationships and phylogenetic position of Ascocotyle were further assessed on a broad phylogeny on the Opisthorchioidea Looss, 1899. Ascocotyle (P.) ornamentata Shalaby et al. (1993) described from decomposed worms (all circumoral spines were detached) found in a dog in Egypt, with no type-specimens of this species deposited in a repository collection, is considered to be species inquirenda.

• Klíčová slova
• Digenea, Fish-eating birds, Life-cycle, Marine mammals, Phylogenetic relationships, Silversides, South-western atlantic, Taxonomy,
• Publikační typ
• časopisecké články MeSH