Via molecular and morphological analyses, we describe adult specimens of a new species of Versteria (Cestoda: Taeniidae) infecting mink and river otter (Carnivora: Mustelidae) in Western Canada, as well as larval forms from muskrat and mink. These sequences closely matched those reported from adult specimens from Colorado and Oregon, as well as larval infections in humans and a captive orangutan. We describe here a new species from British Columbia and Alberta (Canada), Versteria rafei n. sp., based upon morphological diagnostic characteristics and genetic distance and phylogeny. Versteria rafei n. sp. differs from the three other described species of the genus in the smaller scolex and cirrus sac. It also differs from V. mustelae (Eurasia) and V. cuja (South America) by having an armed cirrus, which is covered in hair-like bristles, and in the shape of its hooks, with a long thorn-like blade, and short or long handle (vs. a short sharply curved blade and no difference in handle size in previously described species). The poorly known V. brachyacantha (Central Africa) also has an armed cirrus and similarly shaped hooks. However, it differs from the new species in the number and size of hooks. Phylogenetic analysis of the cox1 and nad1 mitochondrial regions showed that our specimens clustered with isolates from undescribed adults and larval infections in North America, and separate from V. cuja, confirming them to be a distinct species from the American Clade.

Attempts to control cystic echinococcosis (CE) caused by Echinococcus granulosus in the Falkland Islands have been ongoing for over 50 years. No human cases have been recorded since the 1980s but there is a need to establish if the parasite has been completely eliminated from domestic animals. A study was carried out in 2018/2019 to identify dogs infected with E. granulosus using copro-antigen and copro-polymerase chain reaction (PCR) analysis. In addition, annual slaughter data were analysed to establish infection levels of E. granulosus and 2 other taeniid parasites. Results showed that 4 out of 589 dogs (0.7%) tested positive by copro-antigen analysis. Results from similar surveys carried out in 2010, 2012 and 2014 showed 17 (3%), 0 and 6 (1%) copro-antigen-positive dogs, respectively, with 8 dogs being confirmed by PCR in 2010. Annual abattoir data showed that from 2006 to 2020, 36 sheep were identified with E. granulosus (mean 0.0055%), 14 186 sheep with Taenia hydatigena (mean 2.2%) and 465 with Taenia ovis (mean 0.072%). Prevalences of T. hydatigena and T. ovis showed spontaneous rises in certain years where the infections could also be detected in lambs indicating that viable taeniid eggs were present. Observations of farm management procedures indicated that there were occasions when dogs could get access to infective taeniid material. In conclusion, E. granulosus is still present in sheep and dogs but at low prevalences. The increasing presence of T. hydatigena however, indicates that control measures are defective in some areas and there is potential for a re-emergence of CE.

The concept of One Health emphasizes the interdependence of human, animal and environmental health and is of growing significance, in part owing to the problems related to emerging infectious diseases of wildlife origin. Wild mammalian predators are a potential risk factor for transmission of zoonotic pathogens to domesticated animals and humans. This is especially relevant in rural areas, where transmission of zoonotic pathogens can occur particularly efficiently when free-ranging dogs are present. The main aim of this study was to determine helminth infections among wild mammalian predators and evaluate the overlap between helminth faunas of wild mammals and dogs. Scat samples of predators were collected in coastal areas of Western Estonia and genetic methodology applied for the correct identification of predator species from their scat. Parasitic helminths of mammalian predators in the scat samples were analysed and compared with dog data from a previous study. High helminth prevalence (~90%) was found in dominant predator species in the area, namely the red fox (Vulpes vulpes) and golden jackal (Canis aureus). Moreover, the helminth fauna of both wild species, including potentially zoonotic helminths, overlapped largely with that of rural dogs in the same area. The results, together with the ones from earlier parasitological studies among humans in Estonia, emphasize the potential risk of pathogen transmission from wild mammalian predators to dogs and from dogs to humans, making parasitic diseases of wildlife a One Health concern.

Regardless of the highly efficient anthelmintics available and the control measures taken by dog owners and veterinarians, gastrointestinal parasites, especially zoonotic helminths, are still abundant in dogs and pose a health risk to humans. Free-ranging dogs in rural areas can be an important source of helminth infection. The aims of the present work were to collect scats of rural dogs, determine the environmental contamination caused by helminth infections among rural dogs of Western Estonia, analyse how diet affects helminth infection rate and compare the findings to a previous study focusing on dog helminths in urban areas of Estonia. To differentiate the scats of dogs from other sympatric canids, a genetic method was applied. Of 328 samples, genetic analysis identified 84 scats belonging to dogs, of which 87.0% were infected with helminths. A high proportion of rural dog scats harboured eggs of Taeniidae (65.5%), followed by Trichuris spp./Eucoleus spp. (15.5%), Uncinaria stenocephala (14.7%) and Toxocara canis (4.3%). Coinfections occurred in 34.5% of the samples, being the most common between Taeniidae and U. stenocephala (41.4%). The intensity model indicated higher helminth infection rate in rural dogs preying on rodents and game. In comparison to urban dogs, rural dogs were nine times more likely to be infected with intestinal parasites. These results emphasize the need to implement measures to reduce helminth infections in dogs living in rural areas of Western Estonia. Among a complex of measures to be taken, we suggest that it is also important to diagnose which gastrointestinal parasite species infect dogs to determine specific anthelmintic treatment against these parasites.

Hydatigera (Cestoda: Taeniidae) is a recently resurrected genus including species seldom investigated in sub-Saharan Africa. We surveyed wild small mammal populations in the areas of Richard Toll and Lake Guiers, Senegal, with the objective to evaluate their potential role as intermediate hosts of larval taeniid stages (i.e. metacestodes). Based on genetic sequences of a segment of the mitochondrial DNA gene cytochrome c oxidase subunit 1 (COI), we identified Hydatigera parva metacestodes in 19 out of 172 (11.0%) Hubert's multimammate mice (Mastomys huberti) and one out of six (16.7%) gerbils (Taterillus sp.) and Hydatigera taeniaeformis sensu stricto metacestodes in one out of 215 (0.5%) Nile rats (Arvicanthis niloticus). This study reports epidemiological and molecular information on H. parva and H. taeniaeformis in West African rodents, further supporting the phylogeographic hypothesis on the African origin of H. parva. Our findings may indicate significant trophic interactions contributing to the local transmission of Hydatigera spp. and other parasites with similar life-cycle mechanisms. We therefore propose that further field investigations of rodent population dynamics and rodent-borne infectious organisms are necessary to improve our understanding of host–parasite associations driving the transmission risks of rodent parasites in West Africa.

This study investigates the level of helminthic infestation in better-cared-for dogs in a middle-class community in suburban Kingston. A canine zoographic study was conducted, and fresh faecal deposits were collected and analysed for helminth life-cycle stages. The survey indicated that 73% (n=93) of households in the study area owned one dog or more (mean=1·4). Resident's attitudes towards canine management suggested that the dog population was, in general, restricted to the residential estate, and most owners claimed to have dewormed their dogs at least as young animals. Of 141 faecal specimens, 58% contained eggs or larvae of one or more of eight helminths: Uncinaria stenocephala (26%), Ancylostoma sp. (23%), Trichuris vulpis (9%), Toxocara canis (8%), Spirocerca lupi (6%), Strongyloides sp. (6%), Apophallus sp. (4%) and taeniids (1%). There was a high level of multiple infection in the host animals, with approximately one fifth of the infected samples containing three or more helminth types. Infection intensity was apparently low, but some dogs harboured heavy worm loads.

The cestode family Taeniidae consists of 2 genera, Taenia and Echinococcus, which both have been the focus of intensive taxonomic and epidemiological studies because of their zoonotic importance. However, a comprehensive molecular phylogeny of this family has yet to be reconstructed. In this study, 54 isolates representing 9 Taenia species were characterized using DNA sequences in the mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes. Phylogenetic relationships within the family Taeniidae were inferred by combining cox1 and nad1 sequence data of the present and previous studies. In the phylogenetic analysis, the genus Echinococcus was shown to be monophyletic, but Taenia proved to be paraphyletic due to the position of T. mustelae as a probable sister taxon of Echinococcus. This indicates that T. mustelae should form a genus of its own. Taenia ovis krabbei was placed distant from T. ovis ovis, as a sister taxon of T. multiceps, supporting its recognition as a distinct species, T. krabbei. High intraspecific sequence variation within both T. polyacantha and T. taeniaeformis suggests the existence of cryptic sister species.

Myophilin is a muscle-associated antigen of the taeniid cestode Echinococcus granulosus. This protein shows a high amino acid sequence homology with calponins and calponin-like proteins, which are proposed to be associated with the regulation of smooth muscle contraction. In order to provide supportive evidence for a relationship between these proteins, we characterized myophilin using electrophoretic, biochemical and molecular biological approaches. Two-dimensional protein electrophoretic separation of E. granulosus larval proteins defined 4 isoelectric isoforms of myophilin (α, β, γ and δ), which appeared to be a consequence of post-translational modification of a single gene product. It was also demonstrated biochemically that E. granulosus myophilin undergoes specific phosphorylation in vitro by protein kinase C (PKC). Finally, myophilin homologues were identified in extracts of Taenia hydatigena and T. ovis by immunoblot. A partial cDNA of the closely related species, E. multilocularis, was isolated by cloning procedures and showed 99% homology with the E. granulosus myophilin gene. The similarities of E. granulosus myophilin with calponins in their tissue localization, protein isoform patterns, ability to be phosphorylated in vitro by PKC, and the relatively conserved nature of the protein among related parasites suggest that myophilin may be associated with smooth muscle contraction.