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A 2-year-old Kunekune sow was submitted for necropsy following death after peritonitis and sepsis. In addition to peritonitis, numerous fluid-filled cysts were identified in the mesentery and hepatic parenchyma, which contained an approximately 1 cm metacestode (cysticercosis). Subsequent molecular characterization confirmed the presence of Taenia hydatigena, a non-zoonotic cestode species. To our knowledge, visceral cysticercosis caused by T. hydatigena has not been previously documented in Kunekune pigs. Taenia solium is a differential diagnosis of public health importance in cases of cysticercosis. Although Taenia solium is not commonly reported nor endemic in the United States, its zoonotic potential warrants consideration in the initial diagnostic assessment. Clinicians should be aware of the presence of T. hydatigena in its definitive and intermediate hosts. [ABSTRACT FROM AUTHOR]

The article presents the discussion on consideration in the differential diagnosis and a travel history important components of the patient interaction. Topics include immunodeficiency or exposure to various wild or domesticated animal species and the potential zoonotic infections expanding the range of parasites capable of causing human disease; and showing abdominal pain, nausea, vomiting, diarrhea, and increasing flatulence.

A new genus, Cordicestus, is proposed to accommodate proteocephalid tapeworms parasitising gars (Lepisosteiformes: Lepisosteidae) in North and Central America that were previously placed in the polyphyletic genus Proteocephalus Weinland, 1858. The new genus differs from other proteocephalid genera by the particular morphology of the scolex, which is small, protrudes apically but has no apical organ, and bears flat, heart-shaped (= cordis) suckers. In addition, the species of the new genus have an elongated cirrus sac with an almost straight internal vas deferens and wide, sinuous ventral osmoregulatory canals with secondary canals directed outwards. The type species of the new genus, Cordicestus singularis (La Rue, 1911) n. comb., is redescribed based on new material from the shortnose gar, Lepisosteus platostomus Rafinesque (type host), and the spotted gar, L. oculatus Winchell, in the United States. Cordicestus rafaeli n. sp. is described from the tropical gar, Atractosteus tropicus Gill, in Mexico. The new species differs from its relatives primarily by the presence of craspedote proglottids (acraspedote in other species) and some biometric features. All species of Cordicestus are revised, including unidentified specimens from A. tropicus and the Cuban gar A. tristoechus (Bloch and Schneider) in Nicaragua and Cuba, respectively, which may be new species, and a key to the identification of these taxa is provided. Molecular data available for two nominal species of the new genus indicate the possible existence of another species of Cordicestus in Lepisosteus in the USA., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background Echinococcus multilocularis is one of the most severe and lethal parasitic diseases of humans, most often reported in Europe and Asia. Only 1 previous case has been documented in the contiguous United States from Minnesota in 1977. European haplotypes have been identified in carnivores and domestic dogs as well as recently in patients in western and central Canada. Methods We used immunohistochemical testing with the monoclonal antibody Em2G11 and a species-specific enzyme-linked immunosorbent assay affinity-purified antigen Em2, as well as COX1 gene sequencing. Results Using pathology, immunohistochemical staining, specific immunodiagnostic testing, and COX1 gene sequencing, we were able to definitively identify E. multilocularis as the causative agent of our patient's liver and lung lesions, which clustered most closely with the European haplotype. Conclusions We have identified the first case of a European haplotype E. multilocularis in the United States and the first case of this parasitic infection east of the Mississippi River. Given the identification of this haplotype in Canada, this appears to be an emerging infectious disease in North America. [ABSTRACT FROM AUTHOR]

Dieffluvium nidulorum n. sp. is described from smallmouth buffalo, Ictiobus bubalus, collected from Menard Creek in the Big Thicket National Preserve, Texas, U.S.A. The new species is characterized by a scolex with 2 medial acetabula, 4 lateral loculi, and a terminal disc; a uterus that extends far anterior of the cirrus sac in 2 lateral loops; and a very large and muscular external seminal vesicle. Postovarian vitellaria may be present or absent. The new species is a member of the Caryophyllaeidae, and most closely resembles Dieffluvium unipapillatum, Rowardleus pennensis, and some species of Biacetabulum. We amend the genus Dieffluvium to reflect additional information provided by the discovery of the new species, and precisely differentiate its members from other similar taxa. [ABSTRACT FROM AUTHOR]

Twenty-three salvaged specimens of Coluber constrictor constrictor Linnaeus (Northern Black Racer) from North Carolina, U.S.A., were examined for gastrointestinal helminths. Eighteen species of helminths (4 trematodes, 2 cestodes, 10 nematodes, and 2 acanthocephalans) are reported, representing 6 new host records and 6 new geographic distribution records. At 52% prevalence, immature physalopterids were the most prevalent helminth, followed by another nematode, Abbreviata terrapenis, at 43%. Specimens of the cestode Oochoristica sp. were the most prevalent (48%) platyhelminth, and macracanthorhynchid cystacanths were the most prevalent (17%) acanthocephalan. [ABSTRACT FROM AUTHOR]

Diphyllobothrium, also known as the "Broad Tapeworm" or "Fish Tapeworm," is a genus of Cestoda acquired through the consumption of undercooked fish. Although infection by a Diphyllobothrium spp. in the United States is rare, it remains an important global zoonosis, with an estimated burden of approximately 20 million people worldwide. A seldom on the Primary Care Physician's differential diagnosis in the United States, Diphyllobothrium spp. should be considered more readily when treating operational service members as they are exposed to endemic regions more frequently than the civilian population. This case presents one such service member diagnosed with Diphyllobothrium while aboard a U.S. naval vessel at sea, illustrating the importance of military medical providers considering Tapeworm infection even when risk factors seem remote. Diagnostic considerations, practical limitations of the Ova and Parasite (O&P) exam, particulars of specimen collection and handling, and recommendations for empiric treatment in the operational setting will be reviewed. [ABSTRACT FROM AUTHOR]

Alveolar and cystic echinococcosis are emerging and reemerging in Europe, Africa, and Asia. The expansion of Echinococcus spp. tapeworms in wildlife host reservoirs appears to be driving this emergence in some areas. Recent studies suggest a similar phenomenon may be occurring in North America. We describe the context of Echinococcus spp. research in North America, with a specific focus on the contiguous United States. Although studies were conducted in the United States throughout the 1900s on various sylvatic and domestic Echinococcus spp. tapeworm cycles, data are lacking for the past ≈30 years. We review previous research, provide analysis of more recent focal studies, and suggest that Echinococcus spp. tapeworms, in particular E. canadensis, may be underrecognized. As a result, we suggest that additional research and surveillance be conducted for these tapeworms in wildlife host reservoirs across the United States. [ABSTRACT FROM AUTHOR]

Neurocysticercosis (NCC) is a disease caused by central nervous system infection by the larval stage of the pork tapeworm, Taenia solium. In developing countries, NCC is a leading cause of adult-onset epilepsy. Case reports of NCC are increasing among refugees resettled to the United States and other nations, but the underlying prevalence among refugee groups is unknown. We tested stored serum samples from the Centers for Disease Control and Prevention Migrant Serum Bank for antibodies against T. solium cysts by using the enzyme-linked immunoelectrotransfer blot. Seroprevalence was high among all 4 populations tested: refugees from Burma (23.2%), Lao People's Democratic Republic (18.3%), Bhutan (22.8%), and Burundi (25.8%). Clinicians caring for refugee populations should suspect NCC in patients with seizure, chronic headache, or unexplained neurologic manifestations. Improved understanding of the prevalence of epilepsy and other associated diseases among refugees could guide recommendations for their evaluation and treatment before, during, and after resettlement. [ABSTRACT FROM AUTHOR]

Neurocysticercosis results from the infestation of the central nervous system with invading tapeworm larvae. Though uncommon in the US prior to 1965, new cases are currently being diagnosed at an unprecedented rate. Drawing on environmental health, intervention and risk data retrieved from standard/alternative databases and in-country sources, we present an update and summary of modifiable risk factors and field-tested primary prevention measures. While points of intervention, subpopulations at risk and overall magnitude of the problem are addressed, particular attention is paid to defining risk reduction measures that can be adopted by individuals and high risk groups in the near-term to interrupt or eliminate pathways of exposure leading to disease transmission. Though global eradication is not attainable in the near future, effective preventative measures exist and should be taken now by international travellers and workers, US/foreign government agencies, and individuals living in endemic regions to reduce human suffering. [ABSTRACT FROM AUTHOR]

Anoplocephalid cestodes have a worldwide distribution, but relatively few species are known from South American rodents. By examining the collections of the Harold W. Manter Laboratory of Parasitology and the United States National Parasite Collection, 6 new species of Monoecocestus Beddard, 1914, are described, along with a redescription of Monoecocestus mackiewiczi Schmidt and Martin, 1978, based on the type specimens. The discussion includes commentary about uterine development, an important taxonomic character of the family, the vaginal dilation in immature segments (a character of potential taxonomic importance), and the implication of host usage to the evolutionary history and biogeography of species in this genus. [ABSTRACT FROM AUTHOR]

Taenia solium and T. saginata are zoonotic tapeworms of substantial medical and economic importance. Although human taeniasis is widely recognised as an endemic problem in Mexico, its presence in the United States is poorly understood. The first population-based study to estimate the prevalence of human infection with Taenia tapeworms along the Texas–Mexico border has recently been conducted. Households were interviewed in the Texan city of El Paso and in the neighbouring Ciudad Juárez, in Mexico. Faecal samples from household members were then checked for Taenia eggs by flotation and/or for Taenia copro-antigens in an ELISA. The overall prevalence of taeniasis in this border region was found to be 3% but, compared with the residents of Juárez, El Paso residents were 8.6-fold more likely to be tapeworm carriers. The interviews revealed some important differences between the two study sites, particularly the more frequent use of anthelminthic drugs on the Mexican side of the border. These findings have implications in terms of the planning of effective health-education campaigns to decrease the prevalence of taeniasis in the human populations along the Texas–Mexico border. [ABSTRACT FROM AUTHOR]

Abstract: Clinical field trials were conducted at five geographical locations in the USA (Oklahoma, Wisconsin, Tennessee, Virginia and Idaho) to evaluate the efficacy and safety of pyrantel pamoate paste (19.13%, w/w, pyrantel base) administered at the recommended dosage of 13.2mg pyrantel base/kg (6.0mg pyrantel base/lb) body weight (b.w.) against tapeworm infections of Anoplocephala spp. in naturally infected horses. Horses at each study site were allocated by restricted randomization based on the cestode status (positive or negative) of pre-treatment fecal egg counts to complete sets of four animals each or incomplete sets of fewer than four animals. Within sets comprising of two to four horses, one animal was randomly allocated to receive placebo vehicle paste and the remaining horse(s) received pyrantel pamoate paste administered orally at a minimum dosage of 13.2mg pyrantel base/kg b.w. on Test Day (TD) 0. Single animal sets received pyrantel pamoate paste. Fecal samples of horses were collected and examined for equine tapeworm (Anoplocephala spp.) eggs a minimum of four times (once or thrice between TD −28 and −14, twice between TD −14 and −7, and once on TD 0) prior to treatment on TD 0. Fecal samples of horses that were positive for cestode infection pre-treatment were examined for cestode eggs on TD 7, 8, 9, 14, 15 and 16. Cestode-negative pre-treatment horses were not sampled again after treatment. A total of 241 horses (141 mares, 16 stallions and 84 geldings; 6 months–30 yrs of age; 173–646kg; 13 recognized breeds and various crossbreds) were evaluated. The prevalence of Anoplocephala spp. determined by pre-treatment fecal examination ranged from 38.3% in Idaho to 68.1% in Tennessee with an overall prevalence of 52.3%. Ninety cestode-positive and 88 cestode-negative horses were treated with pyrantel pamoate paste, 36 cestode-positive and 27 cestode-negative horses were treated with placebo vehicle paste. Overall, 178 horses were treated with pyrantel pamoate paste, and 63 horses were treated with placebo paste. Of the 178 horses treated with pyrantel pamoate paste, no drug related, adverse clinical or neurological health events were observed. No doses of pyrantel pamoate paste were refused or lost during dosing. At each post-treatment time sampling interval, significantly fewer cestode eggs (P <0.0115) were passed by cestode-positive horses treated with pyrantel pamoate paste compared to cestode-positive horses that received placebo paste. Efficacy of the pyrantel pamoate paste treatment ranged from 92 to 96% from TD 7 to TD 16 with an overall efficacy of 95%. The results of these trials demonstrated that pyrantel pamoate paste (19.13%, w/w, pyrantel base) administered orally at a dosage of 13.2mg pyrantel base/kg b.w. is highly efficacious (95%) against Anoplocephala spp. and safe for use in horses with no adverse clinical or neurological health events observed under field use conditions. [Copyright &y& Elsevier]

Morphological and molecular evaluation of tapeworms of the genus Bothriocephalus Rudolphi, 1808 (Cestoda: Bothriocephalidea), based on newly collected and uniformly fixed worms from freshwater fishes in Canada and the United States has revealed unexpected diversity. With a combination of selected morphological features and 4 molecular markers (18S rDNA V8 region, ITS1, ITS2, and COI gene sequences), the following morphotypes and lineages of the Bothriocephalus cuspidatus Cooper, 1917 complex were identified, several of which are specific to their respective fish definitive hosts and may represent separate species: B. cuspidatus sensu stricto from walleye, Sander vitreus (type host), which likely includes a miniature morphotype from Johnny darter, Etheostoma nigrum (both Percidae); Bothriocephalus morphotype from pumpkinseed, Lepomis gibbosus (Centrarchidae); and Bothriocephalus morphotype from rock bass, Ambloplites rupestris (Centrarchidae). The Bothriocephalus morphotype from goldeye, Hiodon alosoides (Hiodontidae), may also represent a separate lineage (possibly Bothriocephalus texomensisSelf, 1954) but requires additional studies. A morphotype from smallmouth bass, Micropterus dolomieu, based on a single specimen, is morphologically and genetically very similar to the morphotype from rock bass. Morphological study of the scolex and strobila of heat-killed and fixed specimens has revealed consistent differences, often subtle, that allowed us to differentiate between these morphotypes., (© American Society of Parasitologists 2020.)

A survey of the species of the Proteocephalus-aggregate from sticklebacks (Actinopterygii: Gasterosteidae) is provided. The occurrence of three species in North America is confirmed: (i) Proteocephalus filicollis (Rudolphi, 1802), which has been reported from the three-spined stickleback, Gasterosteus aculeatus Linnaeus, in the northeastern part of North America (Newfoundland); (ii) Proteocephalus pugetensis Hoff et Hoff, 1929 occurs also in G. aculeatus, but in northwestern North America (British Columbia and Washington); and (iii) Proteocephalus culaeae sp. n., which is described from the brook stickleback, Culaea inconstans (Kirtland), in Manitoba (Canada). Another species, Proteocephalus ambiguus (Dujardin, 1845), a specific parasite of the nine-spined stickleback, Pungitius pungitius (Linnaeus), and type species of the genus, has also been found in North America (Alberta, Canada), but its vouchers are in poor condition and cannot be reliable assigned to this species. Both species reported from three-spined stickleback differ from each other by the shape of the scolex (rounded in P. filicollis versus continuously tapered towards the anterior extremity in P. pugetensis) and the apical sucker (widely oval to subspherical in frontal view in P. filicollis versus flattened in P. pugetensis). Proteocephalus culaeae sp. n. is characterised by a short body composed of a few, continuously widened proglottids, a short scolex narrower than the strobila and devoid of an apical sucker, a short, pyriform cirrus sac, no vaginal sphincter, and few testes. A key to species of the Proteocephalus-aggregate from sticklebacks is provided.

Background: The distribution of Taenia saginata in the Americas is unclear. Establishing the distribution, economic burden, and potentials for control of bovine cysticercosis is increasingly important due to the growing demand for beef. This paper aims to take the first step and reviews the recent distribution of T. saginata taeniosis and bovine cysticercosis on a national level within the Americas. Methods: We undertook a systematic review of published and grey literature for information on the occurrence, prevalence, and geographical distribution of bovine cysticercosis and human taeniosis in the 54 countries and territories of the Americas between January 1st, 1990 and December 31st, 2017. Data on bovine cysticercosis from OIE reports from 1994 to 2005 were also included. Results: We identified 66 papers from the Americas with data on the occurrence of taeniosis or bovine cysticercosis and an additional 19 OIE country reports on bovine cysticercosis. Taeniosis was reported from 13 countries, with nine of these countries reporting specifically T. saginata taeniosis, and four countries reporting non-species specific taeniosis. The reported prevalence of taeniosis ranged between 0.04–8.8%. Bovine cysticercosis was reported from 19 countries, nine identified through the literature search, and an additional 10 identified through the OIE country reports for notifiable diseases. The reported prevalence of bovine cysticercosis ranged between 0.1–19%. Disease occurrence was restricted to 21 countries within the Americas, the majority from the mainland, with the only island nations reporting either bovine cysticercosis or taeniosis being Cuba, Haiti, and the US Virgin Islands. Conclusions: Taenia saginata is widely distributed across 21 of the 54 countries in the Americas, but insufficient epidemiological data are available to estimate the subnational spatial distribution, prevalence, incidence and intensity of infections. This needs to be addressed through active surveillance and disease detection programmes. Such programmes would improve the data quantity and quality, and may enable estimation of the economic burden due to bovine cysticercosis in the region in turn determining the requirement for and cost-effectiveness of control measures. [ABSTRACT FROM AUTHOR]