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The Veterinary Clinics of North... Nov 1987Dogs and cats become infected with tapeworms by ingesting intermediate hosts that contain encysted juvenile tapeworms called larvae. The dog or cat is said to be the... (Review)
Review
Dogs and cats become infected with tapeworms by ingesting intermediate hosts that contain encysted juvenile tapeworms called larvae. The dog or cat is said to be the definitive host because it shelters the sexually reproductive, egg-producing stage of the tapeworm. The intermediate hosts, which are vertebrates in the case of Taenia and Mesocestoides and insects in the case of Dipylidium and Hymenolepis, become infected by ingesting unhatched but infective tapeworm eggs discharged in the feces of the dog or cat. The relatively less common Diphyllobothrium and Spirometra tapeworms discharge eggs that are undeveloped when passed in the feces and must fall into water to undergo development to the coracidium stage. Diphyllobothrium and Spirometra may have two or three aquatic intermediate hosts in series. The first of these, a copepod, ingests the free-swimming coracidium or ciliated oncosphere that has hatched from the egg. The final intermediate host containing the larva (plerocercoid) infective for the dog or cat is an aquatic vertebrate (fish, frog, water snake). Thus, dogs and cats become infected with tapeworms by eating uncooked meat or fish or by ingesting certain insects. These intermediate hosts are infected with juvenile tapeworms called larvae, which are the infective form for the dog or cat. The intermediate hosts, in turn, become infected by ingesting tapeworm eggs discharged in the feces of the dog or cat or, in the case of Diphyllobothrium and Spirometra, by ingesting coracidia that have subsequently developed in and hatched from such eggs. By far the most common tapeworms of dogs and cats in North America are D. caninum, T. pisiformis, and T. hydatigena. Therefore, the most common sources of tapeworm infection are, respectively, fleas, wild rabbits, and the uncooked meat and offal of ruminants and swine. Whenever a dose of tapeworm remedy is administered or dispensed, the client should be informed of these potential sources of reinfection. There is considerable overlap in the spectra of activity of currently available cestocides. Mebendazole, fenbendazole, niclosamide, bunamidine, and praziquantel are all effective against Taenia spp. Bunamidine is the drug of choice against Spirometra, Diphyllobothrium, and Mesocestoides. Praziquantel is the drug of choice against Echinococcus and Dipylidium.
Topics: Animals; Cat Diseases; Cats; Cestoda; Cestode Infections; Dog Diseases; Dogs; Intestinal Diseases, Parasitic
PubMed: 3328390
DOI: 10.1016/s0195-5616(87)50003-1 -
Parasites & Vectors Mar 2022Taenia multiceps is a taeniid cestode that inhabits the small intestines of both wild and domestic carnivores. The larval stage, Coenurus cerebralis, is typically found... (Review)
Review
Taenia multiceps is a taeniid cestode that inhabits the small intestines of both wild and domestic carnivores. The larval stage, Coenurus cerebralis, is typically found in the central nervous system (CNS) of a wide range of livestock and, to a lesser extent, in the extra-cerebral tissues of sheep and goats. This review covers all aspects of the life cycle of T. multiceps and its epidemiology, molecular characterization, pathogenesis, diagnosis, therapy, control and zoonotic potential. Coenurosis caused by the larval stage of T. multiceps has a worldwide distribution and is often fatal in intermediate hosts, which can result in substantial economic losses in livestock farming. Molecular characterization using the mitochondrial genes cytochrome c oxidase subunit 1 and nicotinamide adenine dinucleotide dehydrogenase subunit 1 of different T. multiceps populations has revealed significant genetic variation and the presence of three major haplotypes. The disease mostly affects young sheep and is referred to as either acute or chronic coenurosis. Acute coenurosis occurs as a result of oncospheres migrating through the CNS, while chronic coenurosis occurs as a consequence of the coenurus maturing, which causes displacement and pressure atrophy of brain tissue. Non-cerebral coenurosis has been most commonly reported in goats. The best diagnostic method for cerebral coenurosis involves the interpretation of clinical signs with accurate localization of the cyst using diagnostic imaging techniques. A vaccine based on recombinant oncosphere antigens has proved to be an effective tool against T. multiceps infection in sheep. Additionally, use of anthelmintics during the parasite's migration stages reduces the development of cysts in the sheep brain. Surgery is considered the most effective method for the treatment of cerebral coenurosis in small ruminants, but is often not carried out because of the limited finances of many sheep and goat breeders. However, coenurosis can also be controlled effectively through preventative measures, such as anthelmintic treatment of dogs and the proper disposal of intermediate host carcasses. The parasite is also zoonotic, and cases of coenurosis have been reported in humans with coenuri located in the brain, spinal cord and eyes.
Topics: Animals; Cestoda; Cestode Infections; Cysticercosis; Dogs; Sheep; Sheep Diseases; Taenia
PubMed: 35279199
DOI: 10.1186/s13071-022-05210-0 -
Frontiers in Cellular and Infection... 2023
Topics: Animals; Host-Pathogen Interactions; Cestoda
PubMed: 37767200
DOI: 10.3389/fcimb.2023.1283267 -
The Korean Journal of Parasitology Feb 2015Serine proteases form one of the most important families of enzymes and perform significant functions in a broad range of biological processes, such as intra- and... (Review)
Review
Serine proteases form one of the most important families of enzymes and perform significant functions in a broad range of biological processes, such as intra- and extracellular protein metabolism, digestion, blood coagulation, regulation of development, and fertilization. A number of serine proteases have been identified in parasitic helminths that have putative roles in parasite development and nutrition, host tissues and cell invasion, anticoagulation, and immune evasion. In this review, we described the serine proteases that have been identified in parasitic helminths, including nematodes (Trichinella spiralis, T. pseudospiralis, Trichuris muris, Anisakis simplex, Ascaris suum, Onchocerca volvulus, O. lienalis, Brugia malayi, Ancylostoma caninum, and Steinernema carpocapsae), cestodes (Spirometra mansoni, Echinococcus granulosus, and Schistocephalus solidus), and trematodes (Fasciola hepatica, F. gigantica, and Schistosoma mansoni). Moreover, the possible biological functions of these serine proteases in the endogenous biological phenomena of these parasites and in the host-parasite interaction were also discussed.
Topics: Animals; Cestoda; Host-Parasite Interactions; Life Cycle Stages; Nematoda; Serine Proteases; Trematoda
PubMed: 25748703
DOI: 10.3347/kjp.2015.53.1.1 -
Parasitology Dec 2022The tapeworms of fishes (Chondrichthyes and Actinopterygii) account one-third (1670 from around 5000) of the total tapeworm (Platyhelminthes: Cestoda) species diversity.... (Review)
Review
The tapeworms of fishes (Chondrichthyes and Actinopterygii) account one-third (1670 from around 5000) of the total tapeworm (Platyhelminthes: Cestoda) species diversity. In total 1186 species from 9 orders occur as adults in elasmobranchs (sharks, rays and chimaeras), and 484 species from 8 orders mature in ray-finned fishes (referred to here as teleosts). Teleost tapeworms are dominated by freshwater species (78%), but only 3% of elasmobranch tapeworms are known from freshwater rays of South America and Asia (Borneo). In the last 2 decades, vast progress has been made in understanding species diversity, host associations and interrelationships among fish tapeworms. In total, 172 new species have been described since 2017 (149 from elasmobranchs and 23 from teleosts; invalidly described taxa are not included, especially those from the Oriental region). Molecular data, however, largely limited to a few molecular markers (mainly 28S rDNA, but also 18S and 1), are available for about 40% of fish tapeworm species. They allowed us to significantly improve our understanding of their interrelationships, including proposals of a new, more natural classification at the higher-taxonomy level (orders and families) as well as at the lower-taxonomy level (genera). In this review, we summarize the main advances and provide perspectives for future research.
Topics: Animals; Phylogeny; Cestoda; Cestode Infections; Elasmobranchii; Diphyllobothrium; Fishes; Fish Diseases
PubMed: 36004800
DOI: 10.1017/S0031182022001202 -
Frontiers in Immunology 2022is a common tapeworm in horses causing colic and even mortalities. Current diagnostic tests to detect infections have their limitations and an improved method is...
is a common tapeworm in horses causing colic and even mortalities. Current diagnostic tests to detect infections have their limitations and an improved method is needed. Immunoreactive excretory/secretory proteins (E/S proteome) of this parasite can provide promising candidates for diagnostic tests. We compared E/S proteins produced by small (length < 20 mm, width < 5 mm) and large (length 20 to 40 mm, width 5 to 10 mm) worms by label-free quantitative proteomics using a database composed of related and proteins for protein identifications. Altogether, 509 E/S proteins were identified after incubating the worms for three and eight hours. The greatest E/S proteome changes suggested both worm size- and time-dependent changes in cytoskeleton remodeling, apoptosis, and production of antigens/immunogens. The E/S proteins collected at the three-hour time point represented the natural conditions better than those collected at the eight-hour time point, and thereby contained the most relevant diagnostic targets. Immunoblotting using antibodies from horses tested positive/negative for indicated strongest antigenicity/immunogenicity with 13-, 30- and 100-kDa proteins, involving a thioredoxin, heat-shock chaperone 90 (Hsp90), dynein light chain component (DYNLL), tubulin-specific chaperone A (TBCA) and signaling pathway modulators (14-3-3 and Sj-Ts4). This is among the first studies identifying new diagnostic targets and antigens eliciting a IgG-response in horses.
Topics: Horses; Animals; Proteome; Proteomics; Immunoblotting; Cestoda; Body Fluids; Echinococcus granulosus
PubMed: 36466892
DOI: 10.3389/fimmu.2022.1045468 -
Parasitology Apr 2020As training in helminthology has declined in the medical microbiology curriculum, many rare species of zoonotic cestodes have fallen into obscurity. Even among... (Review)
Review
As training in helminthology has declined in the medical microbiology curriculum, many rare species of zoonotic cestodes have fallen into obscurity. Even among specialist practitioners, knowledge of human intestinal cestode infections is often limited to three genera, Taenia, Hymenolepis and Dibothriocephalus. However, five genera of uncommonly encountered zoonotic Cyclophyllidea (Bertiella, Dipylidium, Raillietina, Inermicapsifer and Mesocestoides) may also cause patent intestinal infections in humans worldwide. Due to the limited availability of summarized and taxonomically accurate data, such cases may present a diagnostic dilemma to clinicians and laboratories alike. In this review, historical literature on these cestodes is synthesized and knowledge gaps are highlighted. Clinically relevant taxonomy, nomenclature, life cycles, morphology of human-infecting species are discussed and clarified, along with the clinical presentation, diagnostic features and molecular advances, where available. Due to the limited awareness of these agents and identifying features, it is difficult to assess the true incidence of these 'forgotten' cestodiases as clinical misidentifications are likely to occur. Also, the taxonomic status of many of the human-infecting species of these tapeworms is unclear, hampering accurate species identification. Further studies combining molecular data and morphological observations are necessary to resolve these long-standing taxonomic issues and to elucidate other unknown aspects of transmission and ecology.
Topics: Animals; Cestoda; Cestode Infections; Humans; Life Cycle Stages; Mesocestoides; Neglected Diseases; Prevalence; Zoonoses
PubMed: 32048575
DOI: 10.1017/S003118202000013X -
PeerJ 2024Cancer is one of the leading causes of death, with an estimated 19.3 million new cases and 10 million deaths worldwide in 2020 alone. Approximately 2.2 million cancer... (Review)
Review
Cancer is one of the leading causes of death, with an estimated 19.3 million new cases and 10 million deaths worldwide in 2020 alone. Approximately 2.2 million cancer cases are attributed to infectious diseases, according to the World Health Organization (WHO). Despite the apparent involvement of some parasitic helminths (especially trematodes) in cancer induction, there are also records of the potential suppressive effects of helminth infections on cancer. Tapeworms such as , , and more seem to have the potential to suppress malignant cell development, although in a few cases the evidence might be contradictory. Our review aims to summarize known epidemiological data on the cancer-helminth co-occurrence in the human population and the interactions of tapeworms with cancers, ., proven or hypothetical effects of tapeworms and their products on cancer cells (., in experimental animals) or . The prospect of bioactive tapeworm molecules helping reduce the growth and metastasis of cancer is within the realm of future possibility, although extensive research is yet required due to certain concerns.
Topics: Animals; Humans; Cestoda; Taenia; Cestode Infections; Helminthiasis; Helminths; Neoplasms
PubMed: 38563013
DOI: 10.7717/peerj.17196 -
Deutsches Arzteblatt International Jul 2022
Topics: Animals; Humans; Cestode Infections; Cestoda
PubMed: 36345590
DOI: 10.3238/arztebl.m2022.0148 -
PeerJ 2022Since 2010, the trypanorhynch tapeworm family Rhinoptericolidae Carvajal & Campbell, 1975 has housed just two distinctive, monotypic genera ( Carvajal & Campbell, 1975...
Since 2010, the trypanorhynch tapeworm family Rhinoptericolidae Carvajal & Campbell, 1975 has housed just two distinctive, monotypic genera ( Carvajal & Campbell, 1975 and Palm, 2010). However, global collections of tapeworms from sharks and rays over the last more than three decades brought to light the need for major revision of the family by suggesting a much greater species-level diversity for the nominal genus . Through synonymy and the description of new species, the number of species in the genus is increased from one to eight. A phylogenetic analysis of the D1-D3 gene region of 28S rRNA (28S), including seven of the now nine species of rhinoptericolids, and a broad sampling of the other Trypanobatoida is the first to recover a monophyletic Rhinoptericolidae. In addition to systematic revision, this study allowed for the first evaluation of the degree of intraspecific interspecific variation in 28S for adult trypanorhynchs across the various hosts and geographic localities from which they have been reported, suggesting a relatively consistent boundary for . It is further suggested that detailed scanning electron microscopy (SEM) images of both the basal and metabasal armatures greatly aid in the interpretation of hook arrangement and shape. A schematic to streamline determination of the tentacular surface presented in scanning electron micrographs and line drawings of trypanorhynchs is presented for species with both two and four bothria. In combination, these methodological refinements can now be used as a model to resolve issues of classification and non-monophyly within both major lineages of the Trypanorhyncha. As a result of the taxonomic work, Carvajal & Campbell, 1975 (previously only known from the American cownose ray from the Chesapeake Bay and the Ticon cownose ray from the Gulf of Mexico, Venezuela, and Brazil) is now known from an additional species of cownose ray and a species of stingray, and is revealed to have a transatlantic distribution. Data from SEM suggest a simpler interpretation of hook arrangement in the metabasal armature for and-in combination with 28S sequence data-support Beveridge & Campbell, 1988 (a former rhinoptericolid) as its junior synonym. The three species formerly assigned to are thus transferred to . Data from light microscopy on whole-mounted specimens and histological sections, SEM, and 28S showed the eutetrarhynchid Schaeffner & Beveridge, 2012b to be morphologically consistent with species of and it is thus transferred to the genus. The type series of was determined to be mixed, representing two distinct species which are here redescribed and described as new, respectively. Two additional novel species of are described from cownose rays from off Mozambique and the Gulf of California.
Topics: Animals; Phylogeny; Cestoda; Cestode Infections; Microscopy, Electron, Scanning; Skates, Fish; Sharks
PubMed: 35186470
DOI: 10.7717/peerj.12865