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Further data on the distribution of Dirofilaria spp. in the Czech Republic in dogs

Jana Juránková, Barbora ©enkyříková Mitková, Marcela Novotná, Lada Hofmannová, Barbora Červená, Dwight D. Bowman, David Modrý

Folia Parasitologica 69:007 (2022) | DOI: 10.14411/fp.2022.007

Based on previously published data, the Czech Republic is regarded an endemic country of the onchocercid nematodes Dirofilaria immitis (Leidy, 1856) and Dirofilaria repens Railliet et Henry, 1911. Nevertheless, while cases of D. repens are commonly reported from dogs in South Moravia, no recent records of D. immitis are available. Therefore, the present study was performed to clarify the occurrence of both species of Dirofilaria Railliet et Henry, 1910. Blood samples of 551 dogs sampled during 2015 and 2016 were analysed microscopically for presence of microfilariae and blood sera were examined by IDEXX SNAP® 4Dx® test (IDEXX, USA). DNA from blood of microscopically positive dogs was extracted and PCR protocol amplifying fragment of cytochrome c oxidase I (COI) gene was performed; PCR products were then sequenced. All dogs from the Bohemian part of the Czech Republic were negative. The prevalence of D. repens in the Moravian region was 5.7 % (27/476). BLAST analyses of obtained sequences confirmed the presence of D. repens (99-100% identical to KX265049). All sampled animals showed a negative result for D. immitis antigen in IDEXX SNAP® 4Dx® test. Our study confirmed the previously reported occurrence of D. repens in South Moravia and revealed its spreading from the epicentre to the north and west. PCR with subsequent sequencing together with negative results for D. immitis antigen in IDEXX SNAP® 4Dx® test revealed only D. repens infection. A previously published autochthonous infection of dogs with D. immitis in South Moravia was not confirmed.

The presence of sporogonic stages of Tetracapsuloides bryosalmonae in Icelandic salmonids detected using in situ hybridisation

Fjóla Rut Svavarsdóttir, Mark A. Freeman, Þórólfur Antonsson, Friðþjófur Árnason, Árni Kristmundsson

Folia Parasitologica 68:020 (2021) | DOI: 10.14411/fp.2021.020

Proliferative kidney disease (PKD) is a widespread temperature-dependent disease in salmonids caused by the myxozoan parasite, Tetracapsuloides bryosalmonae (Canning, Curry, Feist, Longshaw et Okamura, 1999) (Tb). Tb has a two-host life cycle, involving fish as an intermediate host and freshwater bryozoans as the definitive host. Although salmonids are acknowledged as hosts for the parasite, it is less clear which fish species are active hosts in the life cycle of Tb. Differences in infection dynamics have been observed between some fish species, which are thought to be related to the existence of two main Tb-strains, the American and European. Iceland, having three species of indigenous salmonids and positioned geographically between Europe and North America, is an ideal location to study the natural development of Tb in wild fish. The main aim of this study was to determine the genetic origin of Tb in Iceland and confirm whether mature spores are produced in Icelandic salmonids. In this study, Icelandic salmonids were infected with the European Tb-strain. In situ hybridisation revealed that intraluminal sporogonic stages, including mature spores, were commonly observed in all three salmonid species. The presence of intraluminal stages has previously been confirmed in brown trout Salmo trutta Linnaeus and Atlantic salmon S. salar Linnaeus in Europe, but they have only been observed in Arctic charr Salvelinus alpinus (Linnaeus) in North America, infected by the local strain. This is, therefore, the first time that sporogonic stages have been observed in Arctic charr in Europe, where fish are infected with the European Tb-strain. Our data strongly suggest that all the three salmonid species inhabiting Icelandic waters serve as active hosts in the life cycle of Tb. However, for full confirmation, transmission trials are needed.

Bat-infesting chiggers (Acariformes: Trombiculidae) of the Balearic Islands and new data on the genus Trisetica Traub et Evans, 1950

Alexandr A. Stekolnikov, Juan Quetglas

Folia Parasitologica 66:017 (2019) | DOI: 10.14411/fp.2019.017

A sample of chigger mites from bat hosts collected in the Balearic Islands (Western Mediterranean Sea) is found to include two species. These are the first records of bat-infesting chiggers identified to species in Spain. Chiggers collected from Pipistrellus kuhlii (Kuhl) in Menorca are identified as Oudemansidium komareki (Daniel et Dusbábek, 1959); this species, which was known from Austria, Bulgaria, Romania, Slovakia, Moldova, Crimea, and Azerbaijan, is recorded for the first time in Spain. Chiggers collected from Plecotus austriacus (Fischer) in Formentera are identified as Trombicula knighti Radford, 1954, which was insufficiently described from a bat in Yemen and known only from its type locality. We transfer this species to the genus Trisetica Traub et Evans, 1950 and provide its re-description based on paratypes and the material from the Balearic Islands. The species Sasatrombicula (Rudnicula) balcanica Kolebinova, 1966 is synonymised with T. knighti. One species closely related to T. knighti, Trisetica aethiopica (Hirst, 1926), which was recorded in Ghana, Uganda, South Sudan, and Madagascar, is re-described on the basis of its syntype deposited in the Natural History Museum, London, UK. This specimen is designated as lectotype.

The first human case of babesiosis mimicking Reiter's syndrome

Zuzana Strizova, Klara Havlova, Ondrej Patek, Daniel Smrz, Jirina Bartunkova

Folia Parasitologica 67:031 (2020) | DOI: 10.14411/fp.2020.031

Babesiosis is a tick-borne disease that may exhibit a broad range of clinical manifestations. According to the Food and Drug Administration (FDA), Babesia species belong to the most common transfusion-transmitted pathogens (FDA, May 2019), but the awareness of the disease caused by these parasitic protists is still low. In immunocompromised patients, the clinical course of babesiosis may be of extreme severity and may require hospital admission. We demonstrate a case of a young male who experienced severe polytrauma requiring repetitive blood transfusions. Six months later, the patient developed a classic triad of arthritis, conjunctivitis and non-specific urethritis. These symptoms largely mimicked Reiter's syndrome. The patient was later extensively examined by an immunologist, rheumatologist, urologist, and ophthalmologist with no additional medical findings. In the search for the cause of his symptoms, a wide laboratory testing for multiple human pathogens was performed and revealed a babesiosis infection. This was the first case of human babesiosis mimicking Reiter's syndrome. Following proper antimicrobial therapy, the patient fully recovered in four weeks. We aim to highlight that a search for Babesia species should be considered in patients with non-specific symptomatology and a history of blood transfusion or a possible tick exposure in pertinent endemic areas.

A new species of Myxobolus Bütschli, 1882 (Bivalvulida: Myxobolidae) infecting stratum spongiosum of the imperiled sicklefin redhorse, Moxostoma sp. (Cypriniformes: Catostomidae) from the Little Tennessee River, North Carolina, USA

Steven P. Ksepka, Brian H. Hickson, Nathan V. Whelan, Stephen A. Bullard

Folia Parasitologica 67:030 (2020) | DOI: 10.14411/fp.2020.030

The sicklefin redhorse, Moxostoma sp. (Cypriniformes: Catostomidae), is an innominate imperiled catostomid endemic to the Hiwassee and Little Tennessee river basins, which has been restricted to a few tributaries of these systems by impoundments. During collections to propagate sicklefin redhorse for reintroduction, a myxozoan, described herein, was observed infecting sicklefin redhorse in the Little Tennessee River Basin, North Carolina. Myxobolus naylori Ksepka et Bullard sp. n. infects the stratum spongiosum covering the scales of sicklefin redhorse. Myxospores of the new species differ from all congeners by the combination of having a mucous envelope, intercapsular process, and sutural markings as well as lacking an iodinophilic vacuole in the sporoplasm. A phylogenetic analysis of the 18S rDNA gene recovered the new species in a polytomy with Myxobolus marumotoi Li et Sato, 2014 and a clade comprised of species of Myxobolus Bütschli, 1882; Thelohanellus Kudo, 1933, and Dicauda Hoffman et Walker, 1973. Histological sections of infected sicklefin redhorse skin revealed myxospores within a plasmodium in the stratum spongiosum dorsal to scales, encapsulated in collagen fibres, and associated with focal erosion of scales directly beneath the plasmodium; in some instances, the scale was perforated by the plasmodium. The specificity of the new species to sicklefin redhorse may make it a useful biological tag to differentiate sicklefin redhorse from morphologically similar species. The new species is the first parasite reported from sicklefin redhorse, a species of concern to the United States Fish and Wildlife Service. No species of Myxobolus has been reported from species of Moxostoma in the Southeast United States. As it was observed that Myxobolus minutus Rosser, Griffin, Quiniou, Alberson, Woodyard, Mischker, Greenway, Wise et Pote, 2016 is a primary junior homonym of Myxobolus minutus Nemeczek, 1911, we propose the replacement name Myxobolus diminutus (Rosser, Griffin, Quiniou, Alberson, Woodyard, Mischker, Greenway, Wise et Pote, 2016).

Interannual and spatial variation in the parasite communities of Pacific sierra Scomberomorus sierra (Jordan et Starks) on Mexico's Pacific coast

Nataly G. Santos-Bustos, Juan Violante-González, Scott Monks, Princessa J. Villalba-Vásquez, Shirley S. Salas Villalobos, Monserrat S. Acosta-Hernández, Aldo Diaz Gallegos

Folia Parasitologica 67:029 (2020) | DOI: 10.14411/fp.2020.029

The parasite communities of predatory fish can be species rich and diverse, making them effective models for studying the factors influencing temporal and spatial variation in these communities. Over a ten-year period an initial study was done on the metazoan parasite communities of Scomberomorus sierra (Jordan et Starks) from four locations on the south-central Pacific coast of Mexico. Twenty-four metazoan parasite taxa were identified from 674 S. sierra specimens: three species of Monogenea, eight Digenea, one Cestoda, one Acanthocephala, four Nematoda, five Copepoda, and two Isopoda. The parasite communities were characterised by high ectoparasite species richness, with monogeneans and some didymozoid species being numerically dominant. Community structure and species composition varied between locations, seasons and sampling years. Similarity between the component parasite communities was generally low, despite the occurrence of a distinctive set of host-specialist parasites. Interannual or local variations in some biotic and abiotic environmental factors are possible causes of the observed variations in the structure and species composition of the parasite community of S. sierra. Ecological factors were therefore considered to have more influence than phylogenetic aspects (host phylogeny) on parasite community structure.

Development of a PCR for Borrelia burgdorferi sensu lato, targeted on the groEL gene

Giulia Chiappa, Alessandra Cafiso, Elisa Monza, Valentina Serra, Emanuela Olivieri, Claudia Romeo, Chiara Bazzocchi

Folia Parasitologica 67:026 (2020) | DOI: 10.14411/fp.2020.026

Borrelia burgdorferi sensu lato (s.l.) is the etiological agent of Lyme disease, transmitted by ticks of the genus Ixodes Latreille. Diagnosis of Lyme disease in humans is often difficult and a detailed knowledge of the circulation of B. burgdorferi s.l. in tick hosts is therefore fundamental to support clinical procedures. Here we developed a molecular approach for the detection of B. burgdorferi s.l. in North Italian Ixodes ricinus (Linnaeus). The method is based on the amplification of a fragment of the groEL gene, which encodes a heat-shock protein highly conserved among B. burgdorferi s.l. species. The tool was applied in both qualitative and Real-time PCR approaches testing ticks collected in a North Italian area. The obtained results suggest that this new molecular tool could represent a sensitive and specific method for epidemiological studies aimed at defining the distribution of B. burgdorferi s.l. in I. ricinus and, consequently, the exposure risk for humans.

Identification and subcellular localisation of hexokinase-2 in Nosema bombycis

Jiancheng Sun, Feng Zhu, Hongli Chen, Mingshuai Yao, Guanyu Zhu, Yiling Zhang, Qiang Wang, Zhongyuan Shen

Folia Parasitologica 67:023 (2020) | DOI: 10.14411/fp.2020.023

Hexokinase (HXK) is the first key enzyme in the glycolytic pathway and plays an extremely important role in energy metabolism. By searching the microsporidian database, we found a sequence (NBO_27g0008) of Nosema bombycis Nägali, 1857 with high similarity to hexokinase-2, and named it as NbHXK2. The NbHXK2 gene has 894 bp and encodes 297 amino acids with 34.241 kD molecular weight and 5.26 isoelectric point. NbHXK2 contains 31 phosphorylation sites and 4 potential N-glycosylation sites with signal peptides and no transmembrane domain. Multiple sequence alignment showed that NbHXK2 shares more than 40% amino acid identity with that of other microsporidia, and the homology with hexokinase-2 of Nosema tyriae Canning, Curry, Cheney, Lafranchi-Tristem, Kawakami, Hatakeyama, Iwano et Ishihara, 1999, Nosema pyrausta (Paillot, 1927) and Nosema ceranae Fries, Feng, da Silva, Slemenda et Pieniazek, 1996 was 89.17%, 87.82% and 69.86%, respectively. Phylogenetic analysis based on the amino acid sequence of hexokinase showed that all microsporidia cluster together in the same clade, and are far away from animals, plants and fungi, and that N. bombycis is closely related to N. tyriae; N. pyrausta; N. ceranae and Nosema apis Zander, 1909. Immunolocalisation with the prepared polyclonal antibody showed that NbHXK2 was mainly distributed in the cytoplasm and plasmalemma in proliferative, sporulation stage and mature spore of N. bombycis. qRT-PCR assay showed that the NbHXK2 expressed at higher level during spore germination and at early stage of proliferation. These results indicate that N. bombycis may use its own glycolytic pathways to supply energy for infection and development, especially germination and in the early stage of proliferation, and acquire energy from the host through certain ways as well.

New records of Philometra spp. (Nematoda: Philometridae) from marine perciform fishes off Florida, USA, including descriptions of two new species

Frantiąek Moravec, Micah D. Bakenhaster, Theodore S. Switzer

Folia Parasitologica 67:017 (2020) | DOI: 10.14411/fp.2020.017

Recent examinations of marine perciform fishes from off the Florida coast in the Gulf of Mexico and Straits of Florida, USA, revealed the presence of the following six species of Philometra Costa, 1845 (Nematoda: Philometridae): P. haemulontis sp. n. (males and females) from the ovary of Haemulon plumierii (Lacepède) (type host) and H. aurolineatum Cuvier (both Haemulidae); Philometra synagridis Moravec, Bakenhaster et Fajer-Ávila, 2014 (males and females) from the ovary and testes of Lutjanus synagris (Linnaeus) (Lutjanidae); P. margolisi Moravec, Vidal-Martínez et Aguirre-Macedo, 1995 (male) from the ovary of Hyporthodus nigritus (Holbrook) (Serranidae) (new host record; probably a paradefinitive host); P. andersoni sp. n. (male) from the ovary of H. nigritus; Philometra sp. 1 (male) from the ovary of Rhomboplites aurorubens (Cuvier) (Lutjanidae); and Philometra sp. 2 (females) from the subcutaneous tissue of the anterior-most head sinuses of Hyporthodus niveatus (Valenciennes) (Serranidae). Specimens of species are described and illustrated based on light and (except for Philometra sp. 1) scanning electron microscopical examinations. Philometra haemulontis sp. n. differs from all congeners in the unique structure of the gubernaculum, whereas P. andersoni sp. n. can be differentiated from other gonad-infecting congeners parasitising the Serranidae by a combination of morphological features. Females of P. synagridis are described for the first time. Gravid females of Philometra sp. 2 are similar to those of P. morii Moravec, Bakenhaster et Fajer-Ávila, 2010, a subcutaneous parasite of Epinephelus morio (Valenciennes) (Serranidae) in the Gulf of Mexico.

Canine thelaziosis in the Czech Republic: the northernmost autochthonous occurrence of the eye nematode Thelazia callipaeda Railliet et Henry, 1910 in Europe

Milan Jirků, Roman Kuchta, Elena Gricaj, David Modrý, Kateřina Jirků Pomajbíková

Folia Parasitologica 67:010 (2020) | DOI: 10.14411/fp.2020.010

The eye nematode Thelazia callipaeda Railliet et Henry, 1910 (Spirurida: Thelaziidae) is a vector-borne zoonotic nematode infecting a range of wild and domestic carnivores as well as humans. It is considered to be a causative agent of emerging and neglected disease and currently invades central part of Europe. Nematodes were collected from the eye of a dog living in Prague, which never travelled outside the Czech Republic. The nematodes were identified based on their morphology and partial sequence of the cox1 gene as T. callipaeda haplotype 1. This finding represents the northernmost record of autochthonous canine thelaziosis in Europe. The insufficient control of imported animals as well as free movement of dogs and wild carnivores within Europe probably facilitates spreading of T. callipaeda throughout the continent. To better understand the spreading of T. callipaeda and to prevent its zoonotic transmissions, information about the risk of this infection in newly invaded countries should be disseminated not only among veterinarians and physicians, but also within the community of pet owners and hunters.

A novel endosymbiont-containing trypanosomatid Phytomonas borealis sp. n. from the predatory bug Picromerus bidens (Heteroptera: Pentatomidae)

Anna I. Ganyukova, Alexander O. Frolov, Marina N. Malysheva, Viktoria V. Spodareva, Vyacheslav Yurchenko, Alexei Yu. Kostygov

Folia Parasitologica 67:004 (2020) | DOI: 10.14411/fp.2020.004

Here we describe the new trypanosomatid, Phytomonas borealis sp. n., from the midgut of the spiked shieldbugs, Picromerus bidens (Linnaeus), collected in two locations, Novgorod and Pskov Oblasts of Russia. The phylogenetic analyses, based on the 18S rRNA gene, demonstrated that this flagellate is a sister species to the secondary monoxenous Phytomonas nordicus Frolov et Malysheva, 1993, which was concurrently documented in the same host species in Pskov Oblast. Unlike P. nordicus, which can complete its development (including exit to haemolymph and penetration into salivary glands) in Picromerus bidens, the new species did not form any extraintestinal stages in the host. It also did not produce endomastigotes, indispensable for transmission in other Phytomonas spp. These observations, along with the fact that P. bidens overwinters at the egg stage, led us to the conclusion that the examined infections with P. borealis were non-specific. Strikingly, the flagellates from the Novgorod population contained prokaryotic endosymbionts, whereas the parasites from the second locality were endosymbiont-free. This is a first case documenting presence of intracellular symbiotic bacteria in Phytomonas spp. We suggest that this novel endosymbiotic association arose very recently and did not become obligate yet. Further investigation of P. borealis and its intracellular bacteria may shed light on the origin and early evolution of endosymbiosis in trypanosomatids.

Wing morphometric variability of the malaria vector Anopheles (Cellia) epiroticus Linton et Harbach (Diptera: Culicidae) for the duration of the rainy season in coastal areas of Samut Songkhram, Thailand

Tanawat Chaiphongpachara, Sedthapong Laojun

Folia Parasitologica 67:007 (2020) | DOI: 10.14411/fp.2020.007

In Thailand, Anopheles (Cellia) epiroticus Linton et Harbach (Diptera: Culicidae) is the secondary vector of human malaria along coastal regions. While there are some studies of phenotypic variability and population structure of A. epiroticus, more information on morphological variation would enhance epidemiological understanding of medically important mosquito vectors. This research examined morphological variation at three different distances from coastlines of Samut Songkhram Province, Thailand, using landmark-based geometric morphometrics. Wing shape of A. epiroticus was significantly different in the area 0.2 km away from the sea compared to areas 2 and 4 km away from the sea (p < 0.05). Phenotypic variability in wing shape is associated with distance from the sea. Morphological variations in the area closest to the sea were most pronounced, showing a relationship between A. epiroticus and the ecosystem that affects wing geometry. These results provide important information to understand morphological variation of A. epiroticus in coastal areas.

A new R package and web application for detecting bilateral asymmetry in parasitic infections

Matthew T. Wayland, James C. Chubb

Folia Parasitologica 63:039 (2016) | DOI: 10.14411/fp.2016.039

When parasites invade paired structures of their host non-randomly, the resulting asymmetry may have both pathological and ecological significance. To facilitate the detection and visualisation of asymmetric infections we have developed a free software tool, Analysis of Symmetry of Parasitic Infections (ASPI). This tool has been implemented as an R package (https://cran.r-project.org/package=aspi) and a web application (https://wayland.shinyapps.io/aspi). ASPI can detect both consistent bias towards one side, and inconsistent bias in which the left side is favoured in some hosts and the right in others. Application of ASPI is demonstrated using previously unpublished data on the distribution of metacercariae of species of Diplostomum von Nordmann, 1832 in the eyes of ruffe Gymnocephalus cernua (Linnaeus). Invasion of the lenses appeared to be random, with the proportion of metacercariae in the left and right lenses showing the pattern expected by chance. However, analysis of counts of metacercariae from the humors, choroid and retina revealed asymmetry between eyes in 38% of host fish.

Alpine bullhead (Cottus poecilopus Heckel): a potential refuge for Gyrodactylus salaris Malmberg, 1957 (Monogenea)

Tor A. Bakke, Rachel A. Paterson, Jo Cable

Folia Parasitologica 66:018 (2019) | DOI: 10.14411/fp.2019.018

The notifiable freshwater pathogen Gyrodactylus salaris Malmberg, 1957 tends to be a generalist in contrast to other monogeneans. Whilst it causes most damage to its primary host, the Atlantic salmon (Salmo salar Linnaeus), transport and reservoir hosts likely play a key role in maintaining the parasite in the environment. Here, we tested the ability of G. salaris (strain River Lierelva, southern Norway) to infect and reproduce on a population of wild caught alpine bullhead (Cottus poecilopus Heckel). Exposure of alpine bullhead yearlings (0+) to G. salaris for 24 h at low (6.5 °C) or high temperature (11.5 °C) resulted in the establishment of 1 to 104 parasites per fish. Eight to nine days post-infection at high temperature, the infection of G. salaris was eliminated, indicative of innate host immunity. In contrast, at low temperature G. salaris infections persisted for 47-48 days. The relative lengthy infection of alpine bullhead with G. salaris compared to other non-salmonids tested may be due to low temperature and high initial infection load in combination with an epibiont infection. The present results suggest that this non-salmonid may function as a temperature-dependent transport or reservoir host for G. salaris.

Measuring mitochondrial respiration in adherent cells infected with Trypanosoma cruzi Chagas, 1909 using Seahorse extracellular flux analyser

Laura Maria González-Ortiz*, Juana Patricia Sánchez-Villamil*, Mike A. Celis-Rodríguez, Giovanni Lineros, Sandra Sanabria-Barrera, Norma C. Serrano, Melvin Y. Rincon, Paula K. Bautista-Nino

Folia Parasitologica 66:016 (2019) | DOI: 10.14411/fp.2019.016

Infection with Trypanosoma cruzi Chagas, 1909 is reported to increase the production of reactive oxygen species in patients with Chagas disease. Mitochondria dysfunction, host inflammatory response and inadequate antioxidant response are described as the main factors leading to oxidative stress during acute and chronic stages of the disease. The Seahorse XFe24 extracellular flux platform allows energy metabolism determination through mitochondrial respiration and glycolysis measurements. XFe24 platform can be used in in vitro models of T. cruzi-infected cells, which allow the assessment and even modulation of endogenous conditions of infected cells, generating readouts of real-time cellular bioenergetics changes. In this protocol, we standardised the use of XFe24 technology in T. cruzi infected AC16 cardiomyocytes and SGHPL-5 trophoblasts. In addition, we provide a list of optimised assay specifications, advantages and critical steps to be considered during the process. Cardiomyocytes and trophoblasts are attractive target cells to evaluate the metabolic environment in acute, chronic and congenital Chagas transmission scenarios.

Toxoplasma gondii RPL40 is a circulating antigen with immune protection effect

Junxin Xue, Wei Jiang, Jian Li, Wei Xiong, Zhengan Tian, Qiang Zhang, Shuqing Li, Chunfeng Liu, Kehe Huang, Quan Wang

Folia Parasitologica 66:013 (2019) | DOI: 10.14411/fp.2019.013

Screening and identification of protective antigens are essential for the prevention of infections with Toxoplasma gondii (Nicolle et Manceaux, 1908). In our previous study, T. gondii ribosomal-ubiquitin protein L40 (TgRPL40) was identified as a circulating antigen. However, the function and protective value of TgRPL40 was unknown. In the current study, recombinant TgRPL40 was expressed in Escherichia coli BL21 and antibody was prepared. Western blotting analysis indicated that TgRPL40 was present in circulating antigens and excretory/secretary antigens (ESA). Immunofluorescence and immunoelectron microscopy analysis revealed that TgRPL40 protein is widely distributed in the tachyzoites. Immunisation with recombinant TgRPL40 prolonged the survival of mice infected with tachyzoites. Quantitative real-time polymerase chain reaction analysis showed that immunisation with recombinant TgRPL40 reduced the parasite burden in blood, liver, spleen and brain of mice infected with tachyzoites. These observations indicate that TgRPL40 is a circulating antigen and is an effector of immune protection against acute T. gondii infection.

Rhipicephalus sanguineus sensu lato from dogs and dromedary camels in Riyadh, Saudi Arabia: low prevalence of vector-borne pathogens in dogs detected using multiplexed tandem PCR panel

Shona Chandra, Karen Smith, Abdullah D. Alanazi, Mohamed S. Alyousif, David Emery, Jan ©lapeta

Folia Parasitologica 66:007 (2019) | DOI: 10.14411/fp.2019.007

Despite the global distribution of the brown dog tick, Rhipicephalus sanguineus (Latreille, 1806) sensu lato (s.l.), limited information exists about their identity from the Arabian Peninsula. Ticks from free roaming urban dogs and dromedary camels in Riyadh, Saudi Arabia were morphologically identified, confirmed with scanning electron microscopy and characterised at mitochondrial DNA (cox1, 12S rDNA and 16S rDNA). A total of 186 ticks were collected from 65 free roaming dogs (n = 73) and 84 dromedary camels (n = 113). Morphologically, 5.9% (11/186) were R. sanguineus s.l. and Hyalomma spp. (93.5%, 174/186). From within R. sanguineus s.l., the presence of Rhipicephalus cf. camicasi Morel, Mouchet et Rodhain, 1976 (1 dog, 2 camels) and Rhipicephalus turanicus Pomerantsev, 1936 (1 camel) is reported. The examined R. cf. camicasi form a sister group to R. sanguineus s.l. tropical lineage at all DNA markers. Dogs were parasitised by Hyalomma dromedarii Koch, 1844 (n = 59), Hyalomma impeltatum Schulze et Schlottke, 1930 (n = 1), Hyalomma excavatum Koch, 1844 (n = 2), Hyalomma turanicum Pomerantsev, 1946 (n = 1) and Hyalomma rufipes Koch,1844 (n = 1). DNA from dog blood (n = 53) from Riyadh confirmed a low prevalence of canine vector-borne pathogens that does not exceed 5.7% for Babesia spp., Mycoplasma spp., Anaplasma platys, Hepatozoon canis and Ehrlichia canis using multiplexed tandem PCR (MT-PCR) and diagnostic PCR. Low prevalence of R. sanguineus s.l. on dogs likely contributed to the low level of canine vector-borne pathogens in Saudi Arabia. We demonstrate that dogs in the central Arabian Peninsula are more commonly parasitised by Hyalomma spp. than R. sanguineus s.l.

Rhabdochona angusticaudata sp. n. (Nematoda: Rhabdochonidae) from the Japanese eel Anguilla japonica, and new records of some other nematodes from inland fishes in Japan

Frantiąek Moravec, Kazuya Nagasawa

Folia Parasitologica 65:016 (2018) | DOI: 10.14411/fp.2018.016

Collections of parasitic nematodes of fishes from some freshwater and brackish-water localities in Honshu, Shikoku and Hokkaido, Japan, carried out in 1996-2009, yielded the following eight species: Hysterothylacium haze (Machida, Takahashi et Masuuchi, 1978) (Anisakidae), Paraquimperia sp., Pingus sinensis Hsü, 1933 (both Quimperiidae), Heliconema anguillae Yamaguti, 1935 (Physalopteridae), Rhabdochona angusticaudata sp. n., Rhabdochona zacconis Yamaguti, 1935 (both Rhabdochonidae), Ascarophis arctica Polyanskiy, 1952 (Cystidicolidae) and Eustrongylides sp. larvae (Dioctophymatidae). The new species, R. angusticaudata sp. n., described from the intestine of the Japanese eel Anguilla japonica Temminck et Schlegel in the Renjoji River, Shikoku, is mainly characterised by the presence of 14-16 anterior prostomal teeth, non-bifurcated deirids with rounded ends, the length of the left spicule (300-384 µm long), the right spicule with a dorsal barb and non-filamented eggs. The species of Paraquimperia Baylis, 1934 and A. arctica are reported from Japan for the first time. Based on light and scanning electron microscopical examinations, some new morphological data on H. haze, H. anguillae, R. zacconis and A. arctica are provided.

Toxoplasma gondii seropositivity and substance use in US adults

Andrew N. Berrett, Shawn D. Gale, Lance D. Erickson, Evan L. Thacker, Bruce L. Brown, Dawson W. Hedges

Folia Parasitologica 65:011 (2018) | DOI: 10.14411/fp.2018.011

The intracellular parasite Toxoplasma gondii (Nicolle et Manceaux, 1908) infects humans resulting in acute toxoplasmosis, an infection that in immunocompetent people is typically mild but results in persistent latent toxoplasmosis. In that T. gondii appears to affect dopamine synthesis and because addicting drugs affect midbrain dopamine transmission, latent toxoplasmosis could influence substance use. Using both the third and continuous National Health and Nutrition Examination Surveys from the US Centers for Disease Control and Prevention, we used logistic regression to test for associations between T. gondii seropositivity and subject self-report of having ever used tobacco, alcohol, marijuana, cocaine, heroin, or methamphetamine. In the third NHANES dataset, which included data for tobacco, alcohol, marijuana and cocaine, T. gondii seropositivity was associated with a reduced likelihood of self-reported marijuana (OR = 0.71 [95% CI: 0.58; 0.87]; p = 0.001) and cocaine use (OR = 0.72 [95% CI: 0.56; 0.91]; p = 0.006). In the continuous National Health and Nutrition Examination Surveys dataset, which included data for all six substances, T. gondii seropositivity was associated with a reduced likelihood of self-reported tobacco (OR = 0.87 [95% CI: 0.76; 1.00]; p = 0.044), marijuana (OR = 0.60 [95% CI: 0.50; 0.72]; p < 0.001), heroin (OR = 0.60 [95% CI: 0.42; 0.85]; p = 0.005) and methamphetamine use (OR = 0.54 [95% CI: 0.38; 0.77]; p = 0.001). We observed interactions between sex and T. gondii seropositivity in the prediction of self-reported use of tobacco and alcohol. Further, T. gondii seropositivity appeared to remove the protective effect of education and economic status against self-reported cigarette smoking. These findings suggest that T. gondii seropositivity may be inversely associated with some but not all types of substance use in US adults.

High density of fox and cat faeces in kitchen gardens and resulting rodent exposure to Echinococcus multilocularis and Toxoplasma gondii

Matthieu Bastien, Amélie Vaniscotte, Benoit Combes, Gérald Umhang, Estelle Germain, Valentin Gouley, Alice Pierlet, Thomas Quintaine, Marie-Amélie Forin-Wiart, Isabelle Villena, Dominique Aubert, Franck Boué, Marie-Lazarine Poulle

Folia Parasitologica 65:002 (2018) | DOI: 10.14411/fp.2018.002

The faeces of the red fox, Vulpes vulpes (Linnaeus), and the domestic cat, Felis catus (Linnaeus), can be responsible for spreading eggs of Echinococcus multilocularis Leuckart, 1863 and oocysts of Toxoplasma gondii (Nicolle et Manceaux, 1908) into the environment. The accidental ingestion of these eggs or oocysts, through consumption of raw fruits or vegetables grown in or in contact with contaminated soil, can lead to alveolar echinococcosis (AE) or toxoplasmosis in humans. The present study provides a quantitative assessment of the faecal deposition by foxes and cats in kitchen gardens where fruits and vegetables are grown and its consequences for zoonosis transmission. The density of definitive host faeces is considered as one of the main factors in infection risk for intermediate hosts. The density of fox and cat faeces, as well as the prevalence of both AE and toxoplasmosis in rodent populations (contaminated by ingestion of eggs or oocysts), were compared within and outside kitchen gardens. Our results showed that the mean density of fox faeces did not significantly differ between kitchen gardens and habitat edges (0.29 ± 0.04 faeces/m2 vs 0.22 ± 0.02 faeces/m2), the latter being known as an area of high fox faeceal densities. The density of cat faeces was significantly higher within the kitchen garden than outside (0.86 ± 0.22 faeces/m2 vs 0.04 ± 0.02 faeces/m2). The sampled kitchen gardens might therefore be considered as possible hotspots for both fox and cat defecation. Of the 130 rodents trapped, 14% were infected by at least one species of fox or cat intestinal parasite. These rodents were significantly more often infected when they were exposed to a kitchen garden. These results suggest that the deposit of fox and cat faeces in kitchen gardens would significantly impact the risk of human exposure to E. multilocularis and T. gondii. and should be prevented using effective means.

Patterns in the distribution and directional asymmetry of fleas living on the northern white-breasted hedgehog Erinaceus roumanicus

Krzysztof Dudek, Gábor Földvári, Viktória Majláthová, Igor Majláth, Krisztina Rigó, Viktor Molnár, Mária Tóth, Łukasz Jankowiak, Piotr Tryjanowski

Folia Parasitologica 64:026 (2017) | DOI: 10.14411/fp.2017.026

Fleas infecting northern white-breasted hedgehogs, Erinaceus roumanicus (Barrett-Hamilton), collected from 2009-2011 in Budapest (Hungary) were studied. A total of 305 white-breasted hedgehogs were captured and 1,251 fleas were collected. The flea community comprised two species, the hedgehog flea Archaeopsylla erinacei (Bouche, 1835) and the dog flea Ctenocephalides canis (Curtis, 1826), although the latter was only found on three hedgehogs. Fleas were found on half of the host specimens (51%; n = 156) where their distribution was strongly aggregated. The sex ratio of A. erinacei was biased towards females and was correlated with host size. Interestingly, the sex ratio of fleas became more equal on heavier hosts. It had been expected that, under high competition, the sex ratio would be female biased because it is known that female ectoparasites dominate on poorer hosts. The body size of a random sample of 200 fleas (100 female and 100 male) was measured under a microscope. The analyses showed directional asymmetry in two features - the distance between the top of the head and the eye, and head length. In this two body traits the left side was significantly greater than right side in both sexes of A. erinacei. Our data shed light on the complex nature of the flea population infecting northern white-breasted hedgehogs in an urban area.

Castosyringophilus meropis sp. n. (Acariformes: Syringophilidae) - a new quill mite species parasitising the world population of Merops apiaster Linnaeus (Coraciiformes: Meropidae)

Maciej Skoracki, Martin Hromada, Bozena Sikora

Folia Parasitologica 64:024 (2017) | DOI: 10.14411/fp.2017.024

A new species, Castosyringophilus meropis sp. n., found in quills of feathers of the European bee-eater Merops apiaster Linnaeus (Coraciiformes: Meropidae) is described. This new species is close to C. claravis Skoracki et Glowska, 2008 and differs, in females, by the presence apunctate coxal fields (vs sparsely punctate in C. claravis) and by the lengths of setae d1 145-180 µm, f2 170-185 µm and ag3 190-215 µm (vs d1 200-220 µm, f2 230-250 µm and ag3 150-170 µm). We present a vast mite material collected from bee-eaters originated from different localities in Europe, Asia and Africa, both breeding and wintering grounds of this bird. It indicates that the whole world population of the European bee-eater is parasitised by this quill mite species.

Revised classification of the subfamily Leishmaniinae (Trypanosomatidae)

Alexei Y. Kostygov, Vyacheslav Yurchenko

Folia Parasitologica 64:020 (2017) | DOI: 10.14411/fp.2017.020

In the present study, we critically revised the recently proposed classification of the subfamily Leishmaniinae Maslov et Lukeą in Jirků et al., 2012. Agreeing with erection of the genus Zelonia Shaw, Camargo et Teixeira in Espinosa et al., 2017 and the subgenus Mundinia Shaw, Camargo et Teixeira in Espinosa et al., 2017 within the genus Leishmania Ross, 1908, we argue that other changes are not well justified. We propose to: (i) raise Paraleishmania Cupolillo, Medina-Acosta, Noyes, Momen et Grimaldi, 2000 to generic rank; (ii) create a new genus Borovskyia gen. n. to accommodate the former Leptomonas barvae Maslov et Lukeą, 2010 as its type and only species; (iii) leave the subfamily Leishmaniinae as originally defined, but establish two infrafamilies within it: Leishmaniatae infrafam. n. and Crithidiatae infrafam. n.

Genetic diversity of Echinococcus multilocularis in red foxes in Poland: the first report of a haplotype of probable Asian origin

Jacek Karamon, Krzysztof Stojecki, Małgorzata Samorek-Pieróg, Ewa Bilska-Zajac, Mirosław Rózycki, Ewa Chmurzyńska, Jacek Sroka, Jolanta Zdybel, Tomasz Cencek

Folia Parasitologica 64:007 (2017) | DOI: 10.14411/fp.2017.007

The aim of the present study was to estimate the genetic diversity of the cestode Echinococcus multilocularis Leuckart, 1863 in Poland based on sequence analysis of the mitochondrial genes of worms isolated from red foxes, Vulpes vulpes (Linnaeus). Overall, 83 adults of E. multilocularis from the same number of foxes in different parts of Poland were used for analysis. Sequences of the three mitochondrial genes, cytochrome b (cob), NADH dehydrogenase subunit 2 (nad2) and cytochrome c oxidase subunit 1 (cox1), were analysed. Seventy-four individual biological samples were successfully sequenced. Combined sequence analysis of these three genes exhibited fifteen Polish haplotypes (EmPL1-EmPL15). Most isolates (n = 29; 39%) were classified to the EmPL1 haplotype, which occurred mainly in the east, north and centre of Poland. Haplotype EmPL4 (n = 14; 19%) and other haplotypes appeared predominantly in the south and west area. Fourteen haplotypes were grouped in the European clade. One Polish haplotype (EmPL9) (n = 7, 10%) was assigned to the Asian clade with haplotypes from Japan and Kazakhstan. This haplotype was found only in northeast Poland and this is the westernmost report of haplotype of E. multilocularis belonging to the Asian clade in Europe. The investigation demonstrated that populations of E. multilocularis in Poland (and probably also in eastern Europe) included not only different European haplotypes but also those of the Asian origin.

Three new genera of rhinebothriidean cestodes from stingrays in Southeast Asia

Janine N. Caira, Claire J. Healy, Fernando P.L. Marques, Kirsten Jensen

Folia Parasitologica 64:008 (2017) | DOI: 10.14411/fp.2017.008

Three genera of rhinebothriideans, previously referred to as New genus 1, New genus 2 and New genus 4, are erected in the the Anthocephaliidae. New genus 1 is established as Divaricobothrium gen. n., with Divaricobothrium tribelum sp. n. as its type species; Echeneibothrium trifidum Shipley et Hornell, 1906 is transferred to the genus as Divaricobothrium trifidum (Shipley et Hornell, 1906) comb. n. This genus is unique among rhinebothriidean genera in bearing bothridia that are posteriorly deeply divided into two lobes with facial loculi but no apical sucker, and a vagina that extends to near the anterior margin of the proglottid. Its species parasitise Indo-Pacific members of the genera Brevitrygon Last, Naylor et Manjaji-Matsumoto, Maculabatis Last, Naylor et Manjaji-Matsumoto and Pateobatis Last, Naylor et Manjaji-Matsumoto. New genus 2 is established as Barbeaucestus gen. n., with Barbeaucestus jockuschae sp. n. as its type species; Barbeaucestus ralickiae sp. n. is also described. Anthobothrium sexorchidum Williams, 1964 and Rhinebothrium shipleyi Southwell, 1912 are transferred to the genus as Barbeaucestus sexorchidus (Williams, 1964) comb. n. and Barbeaucestus shipleyi (Southwell, 1912) comb. n., respectively. This genus is unique among rhinebothriidean genera in that its bothridia are substantially wider than long, bear an apical sucker and at least one row of two or more facial loculi in their anterior half. Its species parasitise the genera Neotrygon Castelnau and Taeniura Müller et Henle. New genus 4 is established as Sungaicestus gen. n. with transfer of Rhinebothrium kinabatanganensis Healy, 2006, as Sungaicestus kinabatanganensis (Healy, 2006) comb. n., as its type species. Among the genera of its order, this genus most closely resembles Rhinebothrium Linton, 1890, however, despite the original description, the bothridia were found to bear, rather than lack, apical suckers. This monotypic genus is known only from the freshwater stingray Urogymnus polylepis (Müller et Henle). The familial diagnosis of the Anthocephaliidae Ruhnke, Caira et Cox, 2015 is emended. The family now houses five genera.

The molecular phylogeny of the digenean family Opecoelidae Ozaki, 1925 and the value of morphological characters, with the erection of a new subfamily

Rodney A. Bray, Thomas H. Cribb, D. Timothy J. Littlewood, Andrea Waeschenbach

Folia Parasitologica 63:013 (2016) | DOI: 10.14411/fp.2016.013

Large and small rDNA sequences of 41 species of the family Opecoelidae are utilised to produce phylogenetic inference trees, using brachycladioids and lepocreadioids as outgroups. Sequences were newly generated for 13 species. The resulting Bayesian trees show a monophyletic Opecoelidae. The earliest divergent group is the Stenakrinae, based on two species which are not of the type-genus. The next well-supported clade to diverge is constituted of three species of Helicometra Odhner, 1902. Based on this tree and the characters of the egg and uterus, a new subfamily, the Helicometrinae, is erected and defined to include the genera Helicometra, Helicometrina Linton, 1910 and Neohelicometra Siddiqi et Cable, 1960. The subfamily Opecoelinae is found to be monophyletic, but the Plagioporinae is paraphyletic. The single representative of the Opecoelininae (not of the type genus) is nested within a group of deep-sea 'plagioporines'. The two representatives of the Opistholebetidae are embedded within a group of shallow-water 'plagioporine' species. The Opistholebetidae is reduced to subfamily status pro tem as its morphological and biological characteristics are distinctive. This implies that as opecoelid systematics develops with more molecular evidence, several further subfamilies will be recognised. Many of the morphological characters were found to be homoplasious, but the characters defining the Helicometrinae and Opecoelinae, such as filamented eggs, reduced cirrus-sac and uterine seminal receptacle, are closely correlated with the inferred phylogeny.

Scanning and transmission electron microscopy of the histopathological impact of Macrogyrodactylus clarii (Monogenea: Gyrodactylidae) on the gills of catfish, Clarias gariepinus

Mohammed Mohammed El-Naggar, Joanne Cable, Safaa Zaky Arafa, Samir Ahmed El-Abbassy, Graham C. Kearn

Folia Parasitologica 63:017 (2016) | DOI: 10.14411/fp.2016.017

Scanning and transmission electron microscopy (TEM) were used to study the histopathological effects of the monogenean Macrogyrodactylus clarii Gussev, 1961 on the gills of the catfish Clarias gariepinus (Burchell). Suction generated during attachment created 'footprints' on host surfaces in which the host tissues were elevated above the general gill surface. 'Footprints' were bordered by four clefts caused by the muscular flaps on the anterior, lateral and posterior margins of the haptor. The hamuli points penetrate the gill tissue but no evidence was found for the insertion of the marginal hooklets. At the site of attachment, host cells adjacent to the lateral flaps often appeared compressed and widely spaced with large intercellular spaces. Desquamation of these surface epithelia was also apparent and some of the widely spaced epithelial cells had pseudopodium-like processes. Cells within the upper surface epithelial layer of the host were vacuolated and necrotic. Ruptured blood capillaries (blood spaces) in the secondary gill lamellae contained atypical compressed erythrocytes, agranular and granular leucocytes and evidence of haemorrhaging. Cells with fibrotic cytoplasm, putative phagocytes and host mucous cells were evidence of a host response at the site of parasite attachment. The possible role of these cells is discussed in relation to host resistance against infection.

A new coccidian parasite of the boodie, Bettongia lesueur (Mammalia: Marsupialia: Potoroidae), from Australia

Frances Hulst, Leah F. Kemp, Jan ©lapeta

Folia Parasitologica 63:036 (2016) | DOI: 10.14411/fp.2016.036

Four of 28 wild boodies or burrowing bettongs, Bettongia lesueur (Quoy et Gaimard) passed oocysts of species of Eimeria Schneider, 1875. The boodies are surviving on off-shore islands and in large predator-proof sanctuaries on the mainland where they were reintroduced. The boodie is a potoroid marsupial extinct from the mainland of Australia due to predation from red foxes and feral cats. Comparison with other species of the genus Eimeria indicates that the coccidium found represents a new species. Sporulated oocyst of Eimeria burdi sp. n. are pyriform, 21.0-24.0 µm (mean 22.6 µm) by 14.0-16.0 µm (14.9 µm), with a length/width ratio 1.31-1.71 (1.52) and 1-µm-thick yellowish bilayered wall. Micropyle is present at the thinner apex end filled with hyaline body. Polar granules are absent. Sporocysts are ellipsoidal, 10.0-13.5 µm (11.8 µm) by 7.0-8.5 µm (7.4 µm), shape index is 1.42-1.89 (1.63) and a very thin, poorly defined unilayered sporocyst wall is 0.2 µm thick with a domelike almost indistinct Stieda body. Substieda body is indistinct.

Pentastome assemblages of the Nile crocodile, Crocodylus niloticus Laurenti (Reptilia: Crocodylidae), in the Kruger National Park, South Africa

Kerstin Junker, Frikkie Calitz, Danny Govender, Boris R. Krasnov, Joop Boomker

Folia Parasitologica 63:040 (2016) | DOI: 10.14411/fp.2016.040

Thirty-two specimens of the Nile crocodile, Crocodylus niloticus Laurenti (Reptilia: Crocodylidae), from the Kruger National Park, South Africa, and its vicinity were examined for pentastomid parasites during 1995 to 1999 and 2010 to 2011. Pentastomid parasites occurred throughout the year and were widespread in the study area with an overall prevalence of 97% and an overall mean abundance of 23.4 (0-81). Pentastome assemblages comprised six species in three sebekid genera: Alofia nilotici Riley et Huchzermeyer, 1995, A. simpsoni Riley, 1994, Leiperia cincinnalis Sambon, 1922, Sebekia cesarisi Giglioli in Sambon, 1922, S. minor (Wedl, 1861) and S. okavangoensis Riley et Huchzermeyer, 1995. The possible influence of host age, gender and geographic location (river system) on pentastome prevalence, abundance and species richness was investigated. Generally, neither host age, gender nor locality did affect infracommunities, likely because all hosts examined were adult or subadult and displayed comparable foraging behaviour, resulting in similar exposure pathways to fish intermediate hosts. Additionally, the longevity of pentastomids would contribute to accumulative infections as hosts mature. Structuring of pentastome assemblages was observed in as far as S. minor was the dominant species based on overall prevalence and abundance, followed by the equally common species S. cesarisi and L. cincinnalis. With an overall prevalence ranging from 34% to 41% and relatively low abundances, A. nilotici, A. simpsoni and S. okavangoensis form the rarer component of pentastome communities.

The microecology of dactylogyrids (Monogenea: Dactylogyridae) on the gills of wild spotted rose snapper Lutjanus guttatus (Lutjanidae) from Mazatlan Bay, Mexico

Lilia C. Soler-Jiménez, Emma J. Fajer-Ávila

Folia Parasitologica 59[1] 53-58 (2012) | DOI: 10.14411/fp.2012.008

The spatial distribution and coexistence of monogenean dactylogyrids was assessed on the gills of 63 specimens of wild spotted rose snapper, Lutjanus guttatus (Steindachner), caught in the Mazatlan Bay, Sinaloa, Mexico. Five species are reported: Euryhaliotrema perezponcei García-Vargas, Fajer-Ávila et Lamothe-Argumedo, 2008, Euryhaliotrematoides sp., Haliotrematoides spinatus Kritsky et Mendoza-Franco, 2009, H. plectridium Kritsky et Mendoza-Franco, 2009, and H. guttati García-Vargas, Fajer-Ávila et Lamothe-Argumedo, 2008. All except E. perezponcei and H. guttati represent new geographical records for the Pacific coast. The most prevalent dactylogyrid species was E. perezponcei (100%), H. plectridium and H. spinatus had >80% prevalence, and H. guttati and Euryhaliotrematoides sp. had the lowest prevalence. The mean abundance of H. plectridium and E. perezponcei was close to 60 parasites/fish, whereas Euryhaliotrematoides sp. and H. guttati had the lowest abundance. The dactylogyrid species exhibited a tendency for attachment to gill arch 2: 25% attachment occurring on gill arch 1, 30% on 2, 27% on 3 and 18% on 4, and showed a significant preference for the central sector of the gill (42%). Haliotrematoides plectridium had a preference for attachment to gill arches 2 and 3 and the central sector. Haliotrematoides spinatus tended to settle on the gill arches 2 and 3 and had a preference for the central sector. Euryhaliotrema perezponcei tended to settle on the gill arches 1 and 2 and the anterior gill sector. Euryhaliotrematoides sp. and H. guttati did not show a preference for any gill arch or sector. The intraspecific aggregation was stronger than the interspecific aggregation, indicating that all the dactylogyrid species on spotted rose snapper were aggregated, and there was no evidence of competition among the species.

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