Folia Parasitologica最新文献

Bacteria Borrelia burgdorferi s. l. and even more the protist Toxoplasma gondii Nicolle et Manceaux, 1908, are known to affect the behaviour and mental health of their animal and human hosts. Both pathogens infect a significant fraction of human population, both are neurotropic and survive in the host's body for a long time. While latent infections were thought to be clinically asymptomatic, recent studies suggest otherwise, revealing adverse effects on human health. It was hypothesised that the specific behavioural effects of these pathogens may be side effects of general health impairments in infected individuals. This hypothesis was tested using about one hour-long survey consisting of questionnaires and performance tests on a cohort of 7,762 members of the internet population. Results showed that individuals infected with T. gondii reported worse physical and mental health, and those infected with Borrelia spp. reported worse physical health than uninfected controls. Furthermore, infected and noninfected individuals differed in several personality traits, including conscientiousness, pathogen disgust, injury disgust, Machiavellianism, narcissism, tribalism, anti-authoritarianism, intelligence, reaction time, and precision. While the majority of behavioural effects associated with Borrelia infection were similar to those associated with Toxoplasma infection, some differences were observed, such as performance in the Stroop test. Path analyses and nonparametric partial Kendall correlation tests showed that these effects were not mediated by impaired health in infected individuals, contradicting the side effects hypothesis.

Illiosentis Van Cleave et Lincicome, 1939 initially included two species: Illiosentis furcatus Van Cleave et Lincicome, 1939 found in the West Atlantic from Cape Cod in Massachusetts, USA to northern Argentina and Illiosentis cetratus Van Cleave, 1945 with restricted distribution in the Pacific coast of southern California. We are reporting I. furcatus from Peru for the first time and describe a population of I. cetratus from the California corbina, Menticirrhus undulatus (Girard), from southern California. The proboscis hook formula was 14 longitudinal rows for I. furcatus of 18-23 hooks each compared to 16 rows of 19-24 hooks each reported by Van Cleave (1945). We complete the inadequate description of I. cetratus with new information on sexual differentiation in the length of the trunk, dorsal vs. ventral hooks, hook roots, trunk spines, two types of anterior recurved rooted hooks vs. posterior rootless straight hooks, measurements of dorsal and ventral hooks and spines, shape of hook roots, terminal position of the female gonopore, and of position of the cephalic ganglion at the anterior margin of the trunk. We also include new details of the reproductive system in both sexes including Saefftigen's pouch and cement gland ducts. We present new SEM and light microscope images. The Energy Dispersive X-ray analysis (EDXA) shows a high level of sulfur in anterior, middle and posterior hooks in various hook sites, as well as spectra of hook tips with a higher relative concentration of sulfur compared to other hook sites. For the placement of I. cetratus, phylogenetic analysis of sequences of three molecular markers, 18S, 28S rRNA and mitochondrial cox 1 genes, was performed with other related available sequences. The resulting analysis illustrated that I. cetratus was nested within a separate clade along with species of two genera, Dentitruncus truttae Sinzar, 1955 and Neotegorhynchus cyprini Lisitsyna, Xi, Orosová, Barčák et Oros, 2022 represented our species of Illiosentis separate from species of Tegorhynchus Van Cleave, 1921 (as also according to the morphology) with which the Illiosentis species were previously synonymised.

The liver fluke Opisthorchis viverrini (Poirier, 1886) (Digenea) secretes extracellular vesicles (EVs) bearing CD63-like tetraspanins on their surface. Fluke EVs are actively internalised by host cholangiocytes in the bile ducts, where they drive pathology and promote neoplasia through induction of cellular proliferation and secretion of inflammatory cytokines. We investigated the effects of tetraspanins of the CD63 superfamily by co-culturing recombinant forms of the large extracellular loop (LEL) of O. viverrini tetraspanin-2 (rLEL-Ov-TSP-2) and tetraspanin-3 (rLEL-Ov-TSP-3) with non-cancerous human bile duct (H69) and cholangiocarcinoma (CCA, M213) cell lines. The results showed that cell lines co-cultured with excretory/secretory products from adult O. viverrini (Ov-ES) underwent significantly increased cell proliferation at 48 hours but not 24 hours compared to untreated control cells (P < 0.05), whereas rLEL-Ov-TSP-3 co-culture resulted in significantly increased cell proliferation at both 24 hours (P < 0.05) and 48 hours (P < 0.01) time points. In like fashion, H69 cholangiocytes co-cultured with both Ov-ES and rLEL-Ov-TSP-3 underwent significantly elevated Il-6 and Il-8 gene expression for at least one of the time points assessed. Finally, both rLEL-Ov-TSP-2 and rLEL-Ov-TSP-3 significantly enhanced migration of both M213 and H69 cell lines. These findings indicated that O. viverrini CD63 family tetraspanins can promote a cancerous microenvironment by enhancing innate immune responses and migration of biliary epithelial cells.

Cryptosporidium Tyzzer, 1910 is one of the most common protistan parasites of vertebrates. The results of this study provide the first data on Cryptosporidium diversity in the European ground squirrel Spermophilus citellus (Linnaeus). A total of 128 faecal samples of European ground squirrels from 39 localities in the Czech Republic were analysed for the presence of Cryptosporidium spp. by microscopy and PCR/sequence analysis of small subunit ribosomal RNA (SSU) and the actin gene. While the microscopical examination did not reveal the presence of any Cryptosporidium oocysts, eight samples from six localities were PCR-positive. Phylogenetic analyses revealed the presence of five different Cryptosporidium spp. isolates. Four isolates, designated as Cryptosporidium sp. isolate Sc01-04, detected in wild populations and never recorded before, clustered closely to Cryptosporidium genotypes that have previously been found in North American ground squirrels' species. Cryptosporidium sciurinum Prediger, Ježková, Holubová, Sak, Konečný, Rost, McEvoy, Rajský et Kváč, 2021 was found in an animal sanctuary. Because C. sciurinum had previously been detected in Eurasian red squirrels Sciurus vulgaris Linnaeus at the same facility, it can be concluded that this Cryptosporidium was transmitted from tree squirrels to ground squirrels within the animal sanctuary. The results indicate that populations of European and North American ground squirrels are parasitised by different Cryptosporidium spp. At the same time, this is the first description of the occurrence of C. sciurinum in ground squirrels.

Females of species of Lamproglena von Nordmann, 1832 are parasitic on the gills of teleost fishes and the 38 nominal species are based on mainly morphological data. Only four of these species have been genetically characterised and no mitochondrial data are available for the genus. The present study aimed to provide representative ribosomal DNA (rDNA) data for two additional species of Lamproglena from Africa: Lamproglena clariae Fryer, 1956 and Lamproglena hoi Dippenaar, Luus-Powell et Roux, 2001, alongside mitochondrial DNA (mtDNA) for these and two other African species, Lamproglena hemprichii von Nordmann, 1832 and Lamproglena monodi Capart, 1944. The four species were collected from Clariidae, Cyprinidae, Alestidae and Cichlidae, respectively. Representative 18S rDNA and 28S rDNA data were obtained for L. clariae and L. hoi, while cox1 mtDNA was obtained for all four species. The respective haplotypes supported the distinctness of all species using all three gene regions investigated. Interestingly, species appeared to be grouped more by geographical origin than host family, with L. hoi more closely related to other African species than to Asian species also collected from cyprinid hosts. Even though the results presented here greatly add to the molecular data available for Lamproglena, there are still 32 (>80%) species for which no genetic data are available. The interpretation of the results presented here is thus preliminary and much more data are required before the phylogeny of this genus, and other members of the family, such as Lernaea Linnaeus, 1758, can be studied appropriately.

The genus Coitocaecum Nicoll, 1915 is part of the most speciose digenean family, the Opecoelidae Ozaki, 1925, which is found globally in both freshwater and marine fishes. Fifteen opecoelid species have been reported from marine fishes in South Africa, yet only one species of Coitocaecum has been described from this region: Coitocaecum capense Bray, 1987. During an explorative study of the digeneans of the endemic, intertidal fish Clinus superciliosus (Linnaeus) from the Saldanha Bay area, Cape Town harbour, Hermanus, the Tsitsikamma section of the Garden Route National Park and Chintsa East in South Africa, a total of three distinct species of Coitocaecum were identified based on morphological and molecular (28S rDNA, ITS1-5.8S-ITS2 rDNA and COI mtDNA) data: the previously mentioned C. capense, Coitocaecum brayi sp. n. and a third, unnamed species. We provide the first molecular characterisation of species of Coitocaecum from South Africa, accompanied by detailed morphological descriptions. This study illustrates the importance of an integrated taxonomic approach, especially when studying species with similar morphology. These findings further emphasise the lack of information on the true diversity and molecular data for trematodes of marine fishes in South Africa, creating a great capacity for future explorative taxonomic studies and highlighting the use of intertidal areas for conducting such research.

Ticks are important vectors of various pathogens that cause infectious diseases in humans. Endosymbiotic bacteria have been explored as targets for tick and tick-borne disease control. However, the tick bacterial community on Hainan Island, which is the largest tropical island in China and has an environment favourable to ticks, has not yet been studied. In this study, we surveyed the bacterial community of ticks collected from grass in one village in Haikou. A total of 20 ticks were morphologically and molecularly identified as Haemaphysalis spp. The tick bacterial 16S rRNA hypervariable region amplicon libraries were sequenced on an Illumina MiSeq platform. A total of 10 possible bacterial genera were detected, indicating a low-diversity bacterial community profile. The dominant bacterial genus, Massilia, accounted for 97.85% of the population. Some other bacterial genera, including Arsenophonus and Pseudomonas, have been reported to play a role in tick development and tick-borne pathogen transmission in other tick species. Overall, the study highlights the first descriptive understanding of the tick bacterial community on Hainan Island and provides a basis for deciphering the interactions between the tick microbiome and tick-borne pathogens.

Evolutionary and ecological processes affecting the interactions between hosts and parasites in the aquatic environment are at display in the Baltic Sea, a young and ecologically unstable marine ecosystem, where fluctuating abiotic and biotic factors affect the parasitofauna in fish. The dynamic infections of Baltic cod, a subpopulation of the Atlantic cod (Gadus morhua Linnaeus), with third stage anisakid nematode larvae of Pseudoterranova decipiens (Krabbe, 1878) and Contracaecum osculatum (Rudolphi, 1802) have increased following a significant increase of the Baltic grey seal Halichoerus grypus (Fabricius) population in the region. Cod serves as a paratenic host and marine mammals, pinnipeds, are definitive hosts releasing parasite eggs, with faeces, to the marine environment, where embryonation and hatching of the third stage larva take place. The parasite has no obligate intermediate hosts, but various invertebrates, smaller fish and cod act as paratenic hosts transmitting the infection to the seal. Contracaecum osculatum has an impact on the physiological performance of the cod, which optimises transmission of the larva from fish to seal. Thus, a muscle mass decrease of nearly 50% may result from heavy C. osculatum infections, probably amplified by a restricted food availability. The muscle atrophy is likely to reduce the escape reactions of the fish when meeting a foraging seal. In certain regions, where fish and seals are restricted in their migration patterns, such as the semi-enclosed Baltic Sea, the predation may contribute to a severe cod stock depletion. The parasites are zoonotic and represent a human health risk, when consumers ingest insufficiently heat- or freeze-treated infected products. Marked infections of the cod were previously reported during periods with elevated seal populations (late 19th and middle 20th century) and various scenarios for management of risk factors are evaluated in an evolutionary context.

Strange oceanographic events such as El Niño and La Niña may have indirect effects on the local transmission processes of intestinal parasites due to the reduction or increase in populations of potential intermediate or definitive hosts. A total of 713 individuals of Lutjanus inermis (Peters) were collected over an 8-year period (October 2015 to July 2022) from Acapulco Bay, Mexico. Parasite communities in L. inermis were quantified and analysed to determine if they experienced interannual variations in species composition and structure as a result of local biotic and abiotic factors influenced by oceanographic events, such as El Niño-Southern Oscillation (ENSO), or La Niña, the cool phase of the ENSO climate pattern. Twenty-six taxa of metazoan parasites were recovered and identified: two Monogenea, eight Digenea, two Acanthocephala, four Nematoda, one Cestoda, seven Copepoda, and two Isopoda. Species richness at the component community level (8 to 17 species) was similar to reported richness in other species of Lutjanus Bloch. Parasite communities of L. inermis exhibited high inter-annual variation in the abundance of component species of parasite. However, the species richness and diversity were fairly stable over time. Climatic episodes of El Niño and La Niña probably generated notable changes in the structure of local food webs, thus indirectly influencing the transmission rates of intestinal parasite species. Changes in species composition and community structure of parasites possibly were due to variations in feeding behaviour during the events and differences in the host body size.