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Open access

A. Radačovská, E. Bazsalovicsová and I. Králová-Hromadová

Summary

Diphyllobothriosis is a fish-borne parasitic zoonosis caused by so-called “broad tapeworms” or “fish tapeworms” of different genera of the order Diphyllobothriidea. Dibothriocephalus l atus (Linnaeus 1758), (syn. Diphyllobothrium latum), is a medically important type species of the genus, whose occurrence in various European regions is either regular, e.g. in the Alpine lakes region, or occasional and sporadic, e. g. in the Danube River region. For the latter, data on the detection of D. latus plerocercoids in the second intermediate fish host (European perch Perca fluviatilis), as well as in definitive hosts (human and dog), in which infection was directly linked to the consumption of infected fish from the Danube, were published more than 50 years ago. In order to assess the current situation, we aimed to find out whether D. latus is present in the natural environment of the Danube River. In total, 700 perch from five sampling sites in the Slovak part of the Danube River were examined. Plerocercoids were not detected in any fish examined, which leads to the conclusion that D. latus is currently not present in the studied aquatic environment.

Open access

F. D’Azeredo, M. Meira-Filho and T. M. Work

Summary

The present study proposes a new methodology for the quantification of parasite eggs in animal tissue. Quantification of parasites are important to understand epidemiology of spirorchiid infections in sea turtles, however different methodologies for quantifying Spirorchiidae eggs in turtle tissues have been used. The most representative way to quantify Spirorchiidae burdens in tissues is counting eggs / g of tissue, however, this method is very laborious. As an alternative, we propose quantifying number of Spirorchiidae eggs/area of tissue on a microscope slide. We compared this method to number of eggs / slide, a common metric of egg burden in turtle tissues. Both methods correlated well with eggs / g with eggs/mm2 of tissue having better correlation.

Open access

T. M. L. Le, T. D. Nguyen, H. T. Nguyen, G. Liebanas, T. A. D. Nguyen and Q. P. Trinh

Summary

A new root-knot nematode, parasitizing Robusta coffee in Dak Lak Province, Western Highlands of Vietnam, is described as Meloidogyne moensi n. sp. Morphological and molecular analyses demonstrated that this species differs clearly from other previously described root-knot nematodes. Morphologically, the new species is characterized by a swollen body of females with a small posterior protuberance that elongated from ovoid to saccate; perineal patterns with smooth striae, continuous and low dorsal arch; lateral lines marked as a faint space or linear depression at junction of the dorsal and ventral striate; distinct phasmids; perivulval region free of striae; visible and wide tail terminus surrounding by concentric circles of striae; medial lips of females in dumbbell-shaped and slightly raised above lateral lips; female stylet is normally straight with posteriorly sloping stylet knobs; lip region of second stage juvenile (J2) is not annulated; medial lips and labial disc of J2 formed dumbbell shape; lateral lips are large and triangular; tail of J2 is conoid with rounded unstriated tail tip; distinct phasmids and hyaline; dilated rectum. Meloidogyne moensi n. sp. is most similar to M. africana, M. ottersoni by prominent posterior protuberance. Results of molecular analysis of rDNA sequences including the D2–D3 expansion regions of 28S rDNA, COI, and partial COII/16S rRNA of mitochondrial DNA support for the new species status.

Open access

O. O. Boyko and V. V. Brygadyrenko

Summary

The laboratory experiment described in this article evaluated the death rate of larvae of Haemonchus contortus (Rudolphi, 1803) nematodes of the Strongylida order and Strongyloides papillosus (Wedl, 1856) of the Rhabditida order under the impact of different concentrations of 8 flavouring acids and source materials approved for use in and on foods and in medicine (formic, wine, benzoic, salicylic, stearic, kojic, aminoacetic, succinic acids). Minimum LD50 for third stage larvae of (L3) S. papillosus was observed with salicylic and wine acids, for L3 H. contortus larvae – with formic acid. Minimum impact on all studied stages of development of nematodes was caused by stearic, kojic, aminoacetic and succinic acids: larvae did not die in the course of one day even at 1 % concentration of these substances. The best parameters of LD50 were observed for benzoic and formic acid. Further experiments on flavouring acids and source materials approved for use in and on foods and in medicines, and also their compounds, will contribute to developing preparations with a stronger impact on nematode larvae – parasites of the digestive tract of vertebrate animals and humans.

Open access

V. Velev, K. Vutova, T. Pelov and I. Tsachev

Summary

Autochthonous Dirofilaria repens infections have been found in dogs and other carnivores in most European countries. In the same countries, reports of human dirofilariasis are becoming increasingly prevalent. We present 18 cases of people infected with D. repens for a 10-year period traced in our hospital. The data was collected from the observations and tests of all 18 patients from the whole country treated at the Specialized Hospital for Infectious and Parasitic Diseases in Sofia in the period 2009 – 2018. We used a morphological method, serology test and Knott’s method for microfilariae. The patients were 11 to 74 years of age, 12 female and 6 male. In most cases, patients have subcutaneous nodules or face, eyelid and eyes localization. The trend of increasing incidence in Bulgaria continues, with age and sex distribution and localization of the larva being similar to those in other European countries.

Open access

V. León-Règagnon

Summary

Fourty seven specimens of Pelophylax ridibundus were collected in the vicinity of Shiraz, Fars Province, Iran in 1972. Fourteen helminth species were found, eight digeneans (Diplodiscus subclavatus, Halipegus alhaussaini, Haematoloechus similis, Codonocephalus urniger, and four species of metacercariae) and 6 nematodes (Cosmocerca ornata, Rhabdias bufonis, Abbreviata sp., Eustrongylides sp., Onchocercidae gen. sp. and one species of larval nematodes). Of these, only six are adults, while 8 are in their larval stage. The most prevalent helminths were the metacercariae of Codonocephalus urniger (61.7%) and the larvae Abbreviata sp. (55.32%). The adults with the highest prevalence are the digenean Halipegus alhaussaini, and the nematode Cosmocerca ornata (34% in both cases).

Open access

Y. Kitagami, N. Kanzaki and Y. Matsuda

Summary

We morphologically and molecularly characterized segmented filamentous bacteria (SFB) associated with Rhigonema sp. nematodes in millipede hindguts. Seventy-three Riukiaria sp. millipedes were collected from a broad-leaf forest in Japan, and nematodes were excised from the millipede’s hindguts. The occurrence rate of SFB associated with nematodes was 24 % (10/41) for males, 47 % (14/30) for females, and 100 % (2/2) for juveniles. Genomic DNA was extracted from four SFB-rich nematode heads, and we obtained 40 bacterial clones via analysis of nearly full-length 16S rDNA gene sequences. At the phylum level, Firmicutes, Proteobacteria, and Verrucomicrobia accounted for 55 %, 40 %, and 5 % of SFB, respectively. In Firmicutes, Clostridiaceae (28 %) and Lachnospiraceae (15 %) were the dominant groups. Our sequences were divided into seven and three subclades between Firmicutes and Proteobacteria in the phylogenetic tree. In the Firmicutes clade, eight sequences were classified as Lachnospiraceae with a bootstrap value >83 %. A phylogenetic tree involving known uncultured Lachnospiraceae sequences characterized the phylogenetic position of SFB associated with nematodes. Our results suggest that the association of SFB with nematode bodies was probably incidental and that SFB are not always present in millipede hindguts. Our bacterial groups corresponded to those of arthropod hindgut, and SFB associated with nematodes were inferred to belong to Lachnospiraceae. Because the Lachnospiraceae sequences obtained in this study showed specific lineages that differed from all the known deposited sequence data, these groups may be unique to Riukiaria sp.

Open access

M. I. Grano-Maldonado, F. Rubalcava-Ramirez, A. Rodriguez-Santiago, F. Garcia-Vargas, A. Medina-Jasso and M. Nieves-Soto

Summary

The aim of this investigation was to identify the parasites present in the largely understudied pleasure oyster Crassostrea corteziensis in Sinaloa state in the northwestern Mexican Pacific coast. Inspection of twenty-eight oysters collected on “Ceuta” lagoon revealed the presence of the digenean Stephanostomum sp. (Digenea: Acanthocolpidae) cysts. Metacercariae were found encapsulated and embedded in the digestive gland and mantle tissue of oysters. The prevalence of infection revealed that 84.6 % were infected, the abundance was 13.62, with a mean intensity of 16.09 per host. The members of this genus are characterized by a double crown of spines in the cephalic region surrounding the buccal opening of the worm. Significantly, we report the first incidence of the digenean Stephanostomum sp of the family Acanthocolpidae parasitizing Crassostrea corteziensis. Further we report that this bivalve is now considered a new intermediate host, and the northwestern Mexican Pacific coast is a new geographical distribution area for this digenean. The findings contribute to our understanding of the biology, biodiversity and host preference of these parasites, with implications for health risks posed by human consumption of the pleasure oyster.

Open access

J. Čurlík, D. Konjević, M. Bujanić, Ž. Sabol, F. Martinković and M. Sindičić

Summary

Genus Setaria, Viborg 1795, comprises 46 species that parasitize in the peritoneal cavity of Artiodactyla, Perissodactyla and Hyracoidea. The majority of these infections pass unnoticed, but occasionally they can induce severe peritonitis or neurological signs in aberrant hosts and, rarely, even in humans. In this paper we describe for the first time the finding of Setaria tundra in roe deer in Croatia. We examined 45 roe deer and determined the presence of Setaria nematodes in 24.4% of samples, which were subsequently diagnosed as Setaria tundra using molecular methods.

Open access

T. Mačák Kubašková, D. Mudroňová, M. Gergeľ-Čechová and G. Hrčková

Summary

The metacestode stage of the tapeworm Mesocestoides vogae (M. vogae) has the ability of asexual growth in the peritoneal cavity of rodents and other intermediate hosts without restriction. Early immunological events have decisive role in the establishment of infection. In the present study we investigated the kinetic of myeloid and lymphoid cell populations and the proportions of cells undergoing apoptosis in peritoneal cavities of mice within the first month after oral infection with M. vogae larvae. Proportions of cell phenotypes and apoptotic cells were examined by flow cytometry and by microscopical analysis of cells following May/Grünwald staining and fluorescent stain Hoechst 33234, respectively. Total numbers of peritoneal cells increased and their distribution changed towards accumulation of myelo-monocytic cell lineage in the account of reduced proportions of lymphoid cells. CD4+ T cell subpopulations were more abundant than CD8+ and their proportions elevated within two weeks post infection (p.i.) which was followed by a significant decline. Expression level of CD11c marker on myelo-monocytic cells revealed phenotype heterogeneity and proportions of cells with low and medium expression elevated from day 14 p.i. along with concurrent very low presence of CD11chigh phenotype. Lymphoid cell population was highly resistant to apoptosis but elevated proportions of myeloid cells were in early/late stage of apoptosis. Apoptosis was detected in a higher number of adherent cells from day 14 p.i. onwards as evidenced by nuclear fluorescent staining. By contrast, cells adherent to larvae, mostly macrophages and eosinophils, did not have fragmented nuclei. Our data demonstrated that apoptosis did not account for diminished population of peritoneal lymphoid cells and substantial proportions of myeloid cells seem to be more susceptible to apoptotic turnover in peritoneal cavity of mice with ongoing M. vogae infection, suggesting their important role in the host-parasite interactions.