Genetic relatedness and diversity of Capillaria species infecting bayad (Bagrus bajad) in upper Egypt.

BACKGROUND: This study investigates the genetic characteristics of Capillaria isolates from the infected fish, Bagrus bajad, and their relation to human Capillaria philippinensis using Random Amplified Polymorphic DNA (RAPD-PCR) analysis. Fifteen fish Capillaria were isolated and compared to identified human C. philippinensis using six primers: M-are, M-1, G-7, G-11, G-15, and G-18. RESULTS: All six primers successfully amplified DNA, highlighting their efficacy in distinguishing between human and fish Capillaria isolates. The analysis revealed distinctive banding patterns between fish and human isolates, with variations in size and number of DNA fragments. Additionally, genetic similarity analysis showed intriguing patterns of relatedness, with certain pairs exhibiting high similarity percentages. Comparative assessment of RAPD polymorphism demonstrated consistent findings of 100% polymorphism across all primers. The Unweighted Pair Group Method with Arithmetic Mean Algorithm (UPGMA) evaluated the closest relationship between human and fish isolates. These results underscore the utility of RAPD analysis in delineating the genetic diversity among Capillaria isolates from different hosts. CONCLUSION: Overall, this study contributes to our understanding of the genetic variability and relatedness among Capillaria isolates, shedding light on their evolutionary dynamics and zoonotic potential.

Histopathological, morphological, and molecular characterization of fish-borne zoonotic parasite Eustrongylides Excisus infecting Northern pike (Esox lucius) in Iran.

Eustrongylides excisus is a fish-borne zoonotic parasite known to infect various fish species, including Northern pike (Esox Lucius). This nematode, belonging to the family Dioctophymatidae, has a complex life cycle involving multiple hosts. This study aimed to investigate the occurrence of Eustrongylides nematodes in Northern pike (E. Lucius) collected from Mijran Dam (Ramsar, Iran). Between June and October 2023, an investigation was conducted on Northern pike from Mijran Dam in Ramsar, Iran, following reports of reddish parasites in their muscle tissues. Sixty fish were examined at the University of Tehran, revealing live parasites in the muscles, which were then analyzed microscopically and preserved for a multidisciplinary study. The skeletal muscle tissues of 85% (51/60) of fish specimens were infected by grossly visible larvae which were microscopically identified as Eustrongylides spp. In histopathological examination, the lesion was composed of encapsulated parasitic granulomatous myositis. Microscopically, the cystic parasitic granulomas compressed the adjacent muscle fibers, leading to their atrophy and Zenker's necrosis. Moreover, epithelioid macrophages, giant cells and mononuclear inflammatory cells were present around the larvae and between the muscle fibers. Finally, a molecular analysis by examining the ITS gene region, revealed that they belong to the species E. excisus. Eustrongylidiasis in northern Iran necessitates further research into the biology, epidemiology, and control of Eustrongylides nematodes, focusing on various hosts. This study is the first to comprehensively characterize E. excisus in Northern pike in Ramsar, Iran, raising concerns about possible zoonotic transmission.

Tracking the existence of Dioctophyma renale in Parthian Empire of Iran (247 BC-224 AD).

Paleoparasitological investigation in the archeological site of the Caspian Sea littoral revealed the presence of human Dioctophyma renale infection, a ubiquitous kidney-residing helminth of mammals, during the Parthian Empire of Iran (247 BC-224 AD). This study reports the oldest human infection with giant kidney worm in the Middle East, mainly in an area where the infection is reported nowadays. The paucity of records throughout the literature suggests that the same species of parasite occurred with low frequency in the past, as well. The cemetery in the archeological site of Kiasar represented a unique opportunity of studying human and animal parasites of the Parthian Empire in Iran.

An unexpected cause of dysuria in a cat in Poland.

BACKGROUND: Urinary tract infestation by Capillaria spp. in domestic cats is rather rare, but can cause clinical symptoms and affect behaviour. To our knowledge, this report is the first to describe a case of urinary capillariosis in a cat in Poland. CASE PRESENTATION: A female formerly stray cat aged about 1.5 years showing dysuria, stranguria, periuria and lethargy was presented at the veterinary clinic. Urinalysis revealed the presence of Capillaria plica eggs in the sediment. The cat was treated successfully with three topical doses of Broadline (Merial, Toulouse, France). CONCLUSIONS: C. plica is a nematode whose definitive hosts are carnivores, which are infected by eating earthworms (the intermediate hosts). Thus, C. plica infestation is more frequent in wild carnivores and dogs, and rare in cats. Symptomatic bladder capillariosis in cats is very rarely diagnosed and described.

Hepatic Capillaria hepatica (Bancroft, 1893) infection in cat (Felis catus)-histopathological findings and first report from Iran.

Capillaria hepatica (syn. Calodium hepaticum) is a globally distributed nematode with a high affinity to the liver of a wide range of mammalian hosts, including humans. Documented reports of the nematode in cats and associated histopathology are rare. Here, we describe a case of C. hepatica infection in a 5-year-old male stray cat from Iran. At post-car accident necropsy, all body parts appeared normal except for the liver, in which a few yellowish-white granulomatous nodules were observed through the capsule and in the organ. Histopathological examination of the tissue revealed a large number of clustered parasite eggs in the parenchyma. The barrel-shaped, un-embryonated eggs (55.19 × 28.37 µm), with inconspicuous caps at both ends, were covered with striated shells. The presence of ova in the liver tissue had resulted in the development of hepatic inflammation with hepatocellular necrosis associated with the development of multifocal granulomas. As predators of small rodents, the cats might have a significant role in the epidemiology of C. hepatica. Infection of hosts through ingestion of embryonated eggs in contaminated water, food, or soil is of major importance in the epidemiology of C. hepatica. Since the rare reports of feline infection have come mainly from accidental detection of the parasite, any hepatic disease presenting difficulties to find an etiological agent may virtually be associated with the infection with this little-known nematode.

Ecto- and endoparasites of the King's skink (Egernia kingii) on Penguin Island.

Wildlife species are often host to a diversity of parasites, but our knowledge of their diversity and ecology is extremely limited, especially for reptiles. Little is known about the host-parasite ecology of the Australian lizard, the King's skink (Egernia kingii). In spring of 2015, we carried out a field-based study of a population of King's skinks on Penguin Island (Western Australia). We documented five species of parasites, including two ectoparasitic mites (an undescribed laelapid mite and Mesolaelaps australiensis), an undescribed coccidia species, and two nematode species (Pharyngodon tiliquae and Capillaria sp.). The laelapid mite was the most abundant parasite, infesting 46.9% of the 113 captured lizards. This mite species increased in prevalence and abundance over the course of the study. Infection patterns of both mites varied with lizard life-stage; sub-adults were more commonly infested with laelapid mites than adults or juveniles, and sub-adults and adults were infested by more laelapid mites than juveniles. By contrast, adults had a higher prevalence of M. australiensis than juveniles or sub-adults. Among the gastrointestinal parasites, P. tiliquae was relatively common among the sampled lizards (35.3%). These results give new important information about reptiles as parasite hosts and what factors influence infection patterns.

Gastroenteric parasite of wild Galliformes in the Italian Alps: implication for conservation management.

This study provides insights about the diversity, prevalence and distribution of alpine wild galliformes gastrointestinal parasite community, trying to fill a gap in the scientific information currently available in scientific literature. The analysis included three host species: 77 rock partridge (Alectoris graeca saxatilis), 83 black grouse (Tetrao tetrix tetrix) and 26 rock ptarmigan (Lagopus muta helveticus) shot during the hunting seasons 2008-2015. Parasites isolated were Ascaridia compar, Capillaria caudinflata and cestodes. The rock ptarmigan was free from gastrointestinal parasites, whereas the most prevalent helminth (37%) was A. compar in both black grouse and rock partridge. C. caudinflata occurrence was significantly higher in black grouse (prevalence = 10%, mean abundance = 0.6 parasites/sampled animal) than in rock partridge (prevalence = 1.20%, mean abundance = 0.01 parasites/sampled animal). Significant differences were detected among hunting districts. A. compar was found with a significant higher degree of infestation in the hunting districts in the northern part of the study area whereas cestodes abundance was higher in Lanzo Valley. Quantitative analysis of risk factors was carried out using a generalized linear model (GLM) only on the most common parasite (A. compar). Latitude was the only factors associated with infestation risk (OR = 52.4). This study provides information on the composition and variability of the parasite community in the alpine Galliformes species.

Discovery of two highly divergent negative-sense RNA viruses associated with the parasitic nematode, Capillaria hepatica, in wild Mus musculus from New York City.

Recent advances in high-throughput sequencing technology have led to a rapid expansion in the number of viral sequences associated with samples from vertebrates, invertebrates and environmental samples. Accurate host identification can be difficult in assays of complex samples that contain more than one potential host. Using unbiased metagenomic sequencing, we investigated wild house mice (Mus musculus) and brown rats (Rattus norvegicus) from New York City to determine the aetiology of liver disease. Light microscopy was used to characterize liver disease, and fluorescent microscopy with in situ hybridization was employed to identify viral cell tropism. Sequences representing two novel negative-sense RNA viruses were identified in homogenates of wild house mouse liver tissue: Amsterdam virus and Fulton virus. In situ hybridization localized viral RNA to Capillaria hepatica, a parasitic nematode that had infected the mouse liver. RNA from either virus was found within nematode adults and unembryonated eggs. Expanded PCR screening identified brown rats as a second rodent host for C. hepatica as well as both nematode-associated viruses. Our findings indicate that the current diversity of nematode-associated viruses may be underappreciated and that anatomical imaging offers an alternative to computational host assignment approaches.

Let's go swimming: mermithid-infected earwigs exhibit positive hydrotaxis.

Certain species of parasites have the apparent ability to alter the behaviour of their host in order to facilitate the completion of their own life cycle. While documented in hairworms (phylum Nematomorpha), the ability for mermithid parasites (from the sister phylum Nematoda) to force hosts to enter water remains more enigmatic. Here, we present the first experimental evidence in a laboratory setting that an insect which normally never enters open water (the European earwig Forficula auricularia) will readily enter the water when infected with a mermithid nematode (Mermis nigrescens). Only adult mermithids appear capable of inducing this polarising shift in behaviour, with mermithid length being a very strong predictor of whether their host enters water. However, mermithid length was only weakly associated with how long it took an earwig to enter water following the beginning of a trial. Considering the evidence presented here and its alignment with a proteomic investigation on the same host-parasite system, this study provides strong evidence for adaptive behavioural manipulation and a foundational system for further behavioural and mechanistic exploration.

Further evaluation of the efficacy of emamectin benzoate for treating Pseudocapillaria tomentosa (Dujardin 1843) in zebrafish Danio rerio (Hamilton 1822).

Pseudocapillaria tomentosa is a pathogenic nematode parasite, causing emaciation and severe inflammatory lesions in the intestines in zebrafish Danio rerio (Hamilton 1822). Emamectin benzoate is commercially available analogue of ivermectin used for treating salmon for sea lice, under the brand name SLICE® , and we have used this for treating zebrafish with the P. tomentosa. Here, SLICE® , 0.2 per cent active emamectin benzoate, was used for oral treatments at 0.35 mg emamectin benzoate/kg fish/day for 14 days starting at 7 days post-exposure (dpe). Another experiment entailed initiating treatment during clinical disease (starting at 28 dpe). Early treatment was very effective, but delaying treatment was less so, presumably due to inappetence in clinically affected fish. We evaluated emamectin benzoate delivered in water, using Lice-Solve™ (mectinsol; 1.4% active emamectin benzoate) in two experiments. Application of four 24-hr treatments, space over 7 days was initiated at 28 dpe at either 0.168 or 0.56 mg emamectin benzoate/L/bath, and both treatments completely eradicated infections. This was 3 or 10 times manufacture's recommended dose, but was not associated with clinical or histological side effects.

Capillaria Ova and Diagnosis of Trichuris trichiura Infection in Humans by Kato-Katz Smear, Liberia.

We examined human stool samples from Liberia for soil-transmitted helminth ova by Kato-Katz smear and by quantitative PCR. Twenty-five samples were positive for Trichuris trichiura by smear but negative by quantitative PCR. Reexamination of samples showed that they contained Capillaria eggs that resemble T. trichiura in Kato-Katz smears.

Rarely reported, widely distributed, and unexpectedly diverse: molecular characterization of mermithid nematodes (Nematoda: Mermithidae) infecting bumble bees (Hymenoptera: Apidae: Bombus) in the USA.

Mermithid nematodes (Nematoda: Mermithida: Mermithidae) parasitize a wide range of both terrestrial and aquatic invertebrate hosts, yet are recorded in bumble bees (Insecta: Hymenoptera: Apidae: Bombus) only six times historically. Little is known about the specific identity of these parasites. In a single-season nationwide survey of internal parasites of 3646 bumble bees, we encountered six additional instances of mermithid parasitism in four bumble bee species and genetically characterized them using two regions of 18S to identify the specific host-parasite relationships. Three samples from the northeastern USA are morphologically and genetically identified as Mermis nigrescens, whereas three specimens collected from a single agricultural locality in the southeast USA fell into a clade with currently undescribed species. Nucleotide sequences of the V2-V6 region of 18S from the southeastern specimens were 2.6-3.0% divergent from one another, and 2.2-4.0% dissimilar to the nearest matches to available data. The dearth of available data prohibits positive identification of this parasite and its affinity for specific bumble bee hosts. By doubling the records of mermithid parasitism of bumble bee hosts and providing genetic data, this work will inform future investigations of this rare phenomenon.

Calodium hepaticum (Nematoda: Capillariidae) in wild rodent populations from Argentina.

Calodium hepaticum (Nematoda; Capillariidae) is a parasitic nematode of mammals with a cosmopolitan distribution. Adults of this nematode can infect the liver of many mammalian species, including humans, but the main hosts are members of the superfamily Muroidea. Among these, Rattus spp. have the highest apparent prevalences reported worldwide. There are only two reports of C. hepaticum infecting Sigmodontinae species (Muroidea: Cricetidae). In this survey, we examined the occurrence of C. hepaticum in two assemblages of Sigmodontinae rodents from Argentina (Santa Fe and Entre Ríos provinces). The diagnosis was made by morphological features, histopathological exam, and molecular characterization of 18S ribosomal RNA gene region. Here, we show that C. hepaticum is a common parasite of Sigmodontinae. We report the infection in six species (all new hosts): Akodon azarae, Calomys callidus, Calomys venustus, Oligoryzomys flavescens, Oligoryzomys nigripes, and Oxymycterus rufus. This is the first report of C. hepaticum in Sigmodontinae rodents from Argentina and the second record in this subfamily for South America. It is also the first confirmation of C. hepaticum infection in Sigmodontinae by molecular diagnosis. The genetic findings and the prevalences observed, together with the existing information on C. hepaticum, lead us to propose that Rattus spp. brought C. hepaticum to the New World exposing Sigmodontinae rodents, which are frequently infected by this parasite. The high prevalence of infection in A. azarae (41.2%) suggests that this host may be playing an important role in C. hepaticum dynamics in the New World.

First morphological and molecular analysis of Eucoleus boehmi like eggs in dogs from Argentina.

The canid parasites Eucoleus aerophilus (syn. Capillaria aerophila) and Eucoleus boehmi (syn. Capillaria boehmi) parasitize the lower and the upper respiratory tract, respectively. Reports and descriptions of these nematodes are scarce in Argentina, possibly due to misdiagnosis of morphologically similar trichuroids eggs, and the lack of knowledge about the species of Eucoleus in this geographical area. Scanning electron microscopy is a useful tool for identification of E. boehmi eggs based on the characteristics of the shell structure which differentiate between species. Molecular analysis complements morphological identification. Until now, there are no studies based on the analysis of E. boehmi eggs in Argentina. The aim of the present work was to study by morphological, morphometric, and molecular analysis, eggs attributable to E. boehmi isolated from dogs naturally infected in Mar del Plata city, Argentina. Eggs isolated from two dog fecal samples were analyzed by light and scanning electron microscopy. A fragment of mitochondrial DNA (mtDNA) of the cytochrome c oxidase subunit I gene (cox1) from eggs was sequenced, and phylogenetic analysis was performed in this study. According to morphological results based on the wall surface ultrastructure, the eggs studied were assigned to E. boehmi. Molecular analysis supported the morphological identification. The divergence of 9-12% with the European isolated could suggest a new geographical genetic variation of E. boehmi, but also question the possible existence of cryptic species. This is the first characterization of E. boehmi eggs in dogs from Argentina.

Immune responses induced by co-infection with Capillaria hepatica in Clonorchis sinensis-infected rats.

Clonorchis sinensis and Capillaria hepatica are zoonotic parasites that mainly infect the liver and cause serious liver disorders. However, immunological parameters induced by co-infection with these parasites remain unknown. In this study, for the first time, we investigated immunological profiles induced by co-infection with C. hepatica (CH) in C. sinensis (CS)-infected rats (Sprague-Dawley). Rats were infected primarily with 50 metacercariae of C. sinensis; 4 weeks later, they were subsequently infected with 1000 infective C. hepatica eggs. Significantly higher levels of C. sinensis- or C. hepatica-specific IgG antibodies were found in the sera of rats. Interestingly, no cross-reacting antibody was observed between C. sinensis and C. hepatica infections. Significantly raised eosinophil levels were found in the blood of C. sinensis/C. hepatica co-infected rats (CS + CH) compared to the blood of rats infected singly with C. sinensis. Co-infected rats showed significantly higher levels of lymphocyte proliferation and cytokine production compared to a single C. sinensis infection. The worm burden of C. sinensis was significantly reduced in co-infected rats compared to the single C. sinensis infection. These results indicate that the eosinophils, lymphocyte proliferation and cytokine production induced by subsequent infection with C. hepatica in C. sinensis-infected rats might contribute to the observed C. sinensis worm reduction.

Factors affecting carriage and intensity of infection of Calodium hepaticum within Norway rats (Rattus norvegicus) from an urban slum environment in Salvador, Brazil.

Urban slum environments in the tropics are conducive to the proliferation and the spread of rodent-borne zoonotic pathogens to humans. Calodium hepaticum (Brancroft, 1893) is a zoonotic nematode known to infect a variety of mammalian hosts, including humans. Norway rats (Rattus norvegicus) are considered the most important mammalian host of C. hepaticum and are therefore a potentially useful species to inform estimates of the risk to humans living in urban slum environments. There is a lack of studies systematically evaluating the role of demographic and environmental factors that influence both carriage and intensity of infection of C. hepaticum in rodents from urban slum areas within tropical regions. Carriage and the intensity of infection of C. hepaticum were studied in 402 Norway rats over a 2-year period in an urban slum in Salvador, Brazil. Overall, prevalence in Norway rats was 83% (337/402). Independent risk factors for C. hepaticum carriage in R. norvegicus were age and valley of capture. Of those infected the proportion with gross liver involvement (i.e. >75% of the liver affected, a proxy for a high level intensity of infection), was low (8%, 26/337). Sixty soil samples were collected from ten locations to estimate levels of environmental contamination and provide information on the potential risk to humans of contracting C. hepaticum from the environment. Sixty percent (6/10) of the sites were contaminated with C. hepaticum. High carriage levels of C. hepaticum within Norway rats and sub-standard living conditions within slum areas may increase the risk to humans of exposure to the infective eggs of C. hepaticum. This study supports the need for further studies to assess whether humans are becoming infected within this community and whether C. hepaticum is posing a significant risk to human health.

Capillaria hepatica (Calodium hepaticum) infection in a horse: a case report.

BACKGROUND: Capillaria hepatica is a zoonotic parasite in humans and animals and has a worldwide distribution. However, infections in mammals apart from rodents, which are natural hosts of the parasite, have rarely been reported. This report describes the first known case of C. hepatica infection in a horse in Japan. CASE PRESENTATION: A 3-year-old filly without clinical signs was presented at a slaughterhouse in Japan. Gross examination revealed white to tan nodules 0.5 to 1.5 cm in diameter in the parenchyma of the liver. Histologically, the nodules had mature fibrous capsules and consisted of multifocal to coalescing granulomatous inflammations with numerous nematode eggs. The eggs were barrel shaped with an opercular plug on each end and double-layered shells; these findings are consistent with the features of C. hepatica eggs. CONCLUSIONS: To our knowledge, this is the first case of C. hepatica infection in a horse in Japan. The pathological findings confirmed the presence of this pathogen in this part of the world, and they highlight the importance of this nematode in the differential diagnosis of hepatic granulomatous lesions in horses.

A method for collecting eggs of Pseudocapillaria tomentosa (Nematoda: Capillariidae) from zebrafish Danio rerio and efficacy of heat and chlorine for killing the nematode's eggs.

Pseudocapillaria tomentosa is a common pathogen of zebrafish (Danio rerio) in research facilities. We developed a method to collect and concentrate the nematode eggs using a modified sugar centrifugation method and documented their normal development. Embryonating stages with blastomere formation followed by elongation of the embryo prior to larva formation cumulated in developed larvae inside the eggs and hatching after 5-10 day. We then evaluated the efficacy of heat and chlorine to kill them based on a larva development assay. Eggs were exposed to 40, 50, 60 °C for 30 min and 1 h. Chlorine treatment was performed at 100, 250, 500, 1000, 3000 and 6000 ppm for 10 min. Samples exposed to 40 °C for 30 min or 1 h showed incidences of larvated eggs similar to controls. In contrast, no larvation occurred with eggs exposed to either 50 or 60 °C for 30 min or 1 h. Remarkably, in repeated assays, samples exposed to low doses of chlorine (100, 250, 500 and 1000 ppm for 10 min) showed significantly higher incidence of larvation than controls. Eggs treated with 3000 ppm for 10 min did not develop larvae, and no eggs were found after 6000 ppm treatment.

Development and evaluation of a rapid diagnostic immunochromatographic device to detect antibodies in sera from intestinal capillariasis cases.

Intestinal capillariasis, a fish-borne nematodiasis, is an important emerging zoonotic disease. Patients present clinical symptoms of borborygmus chronic diarrhea, intermittent abdominal pain, weight loss, and several degrees of painless lower-leg edema. Death may occur in cases of misdiagnosis and improper treatment. Diagnosis is difficult because of the atypical clinical symptoms and diagnostic confusion with diarrhea caused by gastrointestinal cancer, opportunistic infections in human immunodeficiency virus patients, and hyperthyroidism. In addition, parasite eggs are not always found in stool examination. Serology can provide a supportive diagnostic tool. We have produced a rapid and simple immunochromatographic test (ICT) kit for diagnosis of intestinal capillariasis by detection of diagnostic antibodies in human sera. Serum samples from healthy volunteers and patients with proven intestinal capillariasis and other parasitic diseases were evaluated with the Trichinella spiralis larval extract antigen absorbed ICT strips. The diagnostic sensitivity, specificity, and positive and negative predictive values were 100, 96.6, 90.2, and 100%, respectively. The ICT kit is simple and rapid to use and can supplement stool examination in clinical diagnosis of intestinal capillariasis. The test can be completed in 15 min without a need for any sophisticated instruments or reagents.