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1.
Parasitol Res ; 118(10): 3043-3051, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31471745

RESUMO

Using a combination of morphological and molecular data, we describe a new apicomplexan parasite, Isospora svecica sp. n., from the white-spotted bluethroat, Luscinia svecica cyanecula, from the Czech Republic. Oocysts were found in its intestinal tract. Sporulation was exogenous and took 1-3 days. The oocysts were slightly ellipsoidal, of average size 26.17 × 20.33 µm, with a smooth bilayered wall. Micropyle, oocyst residuum, and polar granules were absent. Sporocysts were bottle-shaped, of an average size of 18.82 × 8.82 µm, with a thin, colourless wall. A conspicuous knob-like Stieda body was present. Substieda body was barely visible. Sporocyst residuum was present in the form of granules of various sizes. Sporozoites were banana-shaped and contained large anterior and small posterior refractile bodies. Partial DNA sequences of three genes were obtained from oocysts of Isospora svecica sp. n., being most closely related to other isosporans described from passerines. Little is known about the parasites of the avian family Muscicapidae, including coccidia, a highly prevalent parasitic protist group in all vertebrate classes. Only six species of the genus Isospora have so far been described in Muscicapidae, together with several "Isospora sp." that in fact most likely represent Isospora lacazei. The newly described Isospora svecica sp. n. differs morphologically from other coccidia reported from muscicapid birds, and represents the first coccidian species described from Luscinia svecica.


Assuntos
Isospora/classificação , Isosporíase/veterinária , Passeriformes/parasitologia , Animais , República Tcheca , Genes de Protozoários/genética , Intestinos/parasitologia , Isospora/citologia , Isospora/genética , Isospora/crescimento & desenvolvimento , Isosporíase/parasitologia , Oocistos/classificação , Oocistos/citologia , Oocistos/genética , Oocistos/crescimento & desenvolvimento , Esporozoítos/classificação , Esporozoítos/citologia , Esporozoítos/genética , Esporozoítos/crescimento & desenvolvimento
2.
Parasitol Res ; 118(12): 3409-3418, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31729572

RESUMO

The arctic fox (Vulpes lagopus), an apex predator with an omnipresent distribution in the Arctic, is a potential source of intestinal parasites that may endanger people and pet animals such as dogs, thus posing a health risk. Non-invasive methods, such as coprology, are often the only option when studying wildlife parasitic fauna. However, the detection and identification of parasites are significantly enhanced when used in combination with methods of molecular biology. Using both approaches, we identified unicellular and multicellular parasites in faeces of arctic foxes and carcasses of sibling voles (Microtus levis) in Svalbard, where molecular methods are used for the first time. Six new species were detected in the arctic fox in Svalbard, Eucoleus aerophilus, Uncinaria stenocephala, Toxocara canis, Trichuris vulpis, Eimeria spp., and Enterocytozoon bieneusi, the latter never found in the arctic fox species before. In addition, only one parasite was found in the sibling vole in Svalbard, the Cryptosporidium alticolis, which has never been detected in Svalbard before.


Assuntos
Arvicolinae/parasitologia , Raposas/parasitologia , Enteropatias Parasitárias/veterinária , Ancylostomatoidea/isolamento & purificação , Animais , Animais Selvagens/parasitologia , Regiões Árticas , Cryptosporidium/isolamento & purificação , Cães , Eimeria/isolamento & purificação , Fezes/parasitologia , Helmintos/isolamento & purificação , Nematoides/isolamento & purificação , Svalbard , Toxocara canis/isolamento & purificação , Trichuris/isolamento & purificação
3.
Mol Phylogenet Evol ; 127: 179-189, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29753710

RESUMO

Recent studies show that host switching is much more frequent than originally believed and constitutes an important driver in evolution of host-parasite associations. However, its frequency and ecological mechanisms at the population level have been rarely investigated. We address this issue by analyzing phylogeny and population genetics of an extensive sample, from a broad geographic area, for commonly occurring parasites of the genus Eimeria within the abundant rodent genera Apodemus, Microtus and Myodes, using two molecular markers. At the most basal level, we demonstrate polyphyletic arrangement, i.e. multiple origin, of the rodent-specific clusters within the Eimeria phylogeny, and strong genetic/phylogenetic structure within these lineages determined at least partially by specificities to different host groups. However, a novel and the most important observation is a repeated occurrence of host switches among closely related genetic lineages which may become rapidly fixed. Within the studied model, this phenomenon applies particularly to the switches between the eimerians from Apodemus flavicollis/Apodemus sylvaticus and Apodemus agrarius groups. We show that genetic differentiation and isolation between A. flavicollis/A. sylvaticus and A. agrarius faunas is a secondary recent event and does not reflect host-parasite coevolutionary history. Rather, it provides an example of rapid ecology-based differentiation in the parasite population.


Assuntos
Biodiversidade , Coccídios/fisiologia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Murinae/parasitologia , Animais , Coccídios/classificação , Coccídios/genética , Genética Populacional , Geografia , Haplótipos/genética , Interações Hospedeiro-Parasita/genética , Filogenia , Fatores de Tempo
4.
J Eukaryot Microbiol ; 62(5): 670-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25939459

RESUMO

A complex wide-range study on the haemoproteid parasites of chelonians was carried out for the first time. Altogether, 811 samples from four tortoise species from an extensive area between western Morocco and eastern Afghanistan and between Romania and southern Syria were studied by a combination of microscopic and molecular-genetic methods. Altogether 160 Haemoproteus-positive samples were gathered in the area between central Anatolia and eastern Afghanistan. According to variability in the cytochrome b gene, two monophyletic evolutionary lineages were distinguished; by means of microscopic analysis it was revealed that they corresponded to two previously described species-Haemoproteus anatolicum and Haemoproteus caucasica. Their distribution areas overlap only in a narrow strip along the Zagros Mts. range in Iran. This fact suggests the involvement of two different vector species with separated distribution. Nevertheless, no vectors were confirmed. According to phylogenetic analyses, H. caucasica represented a sister group to H. anatolicum, and both of them were most closely related to H. pacayae and H. peltocephali, described from South American river turtles. Four unique haplotypes were revealed in the population of H. caucasica, compared with seven haplotypes in H. anatolicum. Furthermore, H. caucasica was detected in two tortoise species, Testudo graeca and Testudo horsfieldii, providing evidence that Haemoproteus is not strictly host-specific to the tortoise host species.


Assuntos
Haemosporida/classificação , Haemosporida/genética , Especificidade de Hospedeiro , Infecções Protozoárias em Animais/parasitologia , Tartarugas/parasitologia , Animais , Citocromos b/genética , DNA de Protozoário , Haemosporida/citologia , Haplótipos , Dados de Sequência Molecular , Filogenia
5.
Parasitology ; 142(6): 816-26, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25736219

RESUMO

The uniform morphology of the developmental stages of Haemogregarina species and the insufficient information supplied by the simplistic descriptions of previous authors complicates their differential diagnosis and proper species identification. In this study, we detected Haemogregarina spp. in 6 out of 22 (27.2%) examined turtles originating from Southeast Asia, Malayemys subtrijuga (n = 4), Sacalia quadriocellata (n = 1) and Platysternon megacephalum (n = 1), and compared them with the available literature data. Microscopic analysis of our isolates distinguished 2 morphological species, Haemogregarina pellegrini and one new species, being described in this paper as Haemogregarina sacaliae sp. n. Phylogenetic analyses based on 1210 bp long fragment of 18S rDNA sequences placed both haemogregarines firmly within the monophyletic Haemogregarina clade. Isolates of H. pellegrini from 2 distantly related turtle hosts, M. subtrijuga and P. megacephalum, were genetically identical. Despite the fact that numerous Haemogregarina species of turtles have been described, the incompleteness of the morphological data and relatively low host specificity provides the space for large synonymy within this taxon. Therefore, a complex approach combining microscopic analyses together with molecular-genetic methods should represent the basic standard for all taxonomic studies.


Assuntos
Apicomplexa/classificação , Apicomplexa/citologia , Infecções Protozoárias em Animais/parasitologia , Animais , Sudeste Asiático , Filogenia , Infecções Protozoárias em Animais/epidemiologia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Especificidade da Espécie , Tartarugas
6.
Parasitology ; 141(4): 522-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24476992

RESUMO

The majority of Haemogregarina species have been based on the morphology of their erythrocytic stages and supposed strict host specificity. The quantity of species with a limited number of overlapping diagnostic traits has led to a considerable mess in haemogregarine taxonomy and significant synonymy. We analysed host specificity, intra- and interspecific variability, evolutionary relationships, and the distribution of the type species of the genus Haemogregarina--H. stepanowi. The morphology of blood stages and 18S rDNA sequences of this haemogregarine from four western Palaearctic hard-shelled freshwater turtles (Emys orbicularis, Mauremys caspica, Mauremys leprosa and Mauremys rivulata) were compared with Haemogregarina balli. Additional sequences of 18S rDNA of Haemogregarina-like isolates collected from three species of African hinged terrapins (genus Pelusios) were used to enlarge the dataset for phylogenetic analyses. Thirteen sequences (1085 bp) of Haemogregarina representing all four western Palaearctic turtle species were identical, corresponding to H. stepanowi, which is closely related to the Nearctic species H. balli. In our analyses, Haemogregarina spp. constituted a monophyletic clade sister to the genus Hepatozoon. Haemogregarina stepanowi possesses a wide distribution range from the Maghreb, through Europe, Turkey and the Middle East to Iran. We consider that the genus Haemogregarina has a low host specificity crossing the family level of its vertebrate hosts and that its distribution is likely to be linked to the vector and definitive host--the leech.


Assuntos
Coccidiose/veterinária , Eucoccidiida/isolamento & purificação , Interações Hospedeiro-Parasita , Sanguessugas/parasitologia , Tartarugas/parasitologia , Animais , Sequência de Bases , Coccidiose/parasitologia , DNA Ribossômico/química , DNA Ribossômico/genética , Vetores de Doenças , Eucoccidiida/classificação , Eucoccidiida/citologia , Eucoccidiida/genética , Feminino , Água Doce , Especificidade de Hospedeiro , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA/veterinária
7.
Parasite ; 31: 1, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38353582

RESUMO

Blood parasites of the genus Hemolivia Petit, Landau, Baccam and Lainson, 1990 (Adeleorina: Karyolysidae) are hemogregarines of ectothermic vertebrates, such as lizards, chelonians, and toads. Only five species of Hemolivia from vertebrate hosts and one from their tick vector have been described so far. In the present study, Central American wood turtles (Rhinoclemmys pulcherrima manni) originating from Southern Nicaragua were screened for the presence of hemogregarines. Ten out of 30 specimens (33.3%) were positive for Hemolivia using both approaches - microscopy and PCR-based analyses. Phylogenetic analyses based on the 18S rRNA gene revealed the presence of two haplotypes, both placed as sister taxa in the Hemolivia clade. Their phylogenetic position was supported by high bootstrap values and high posterior probabilities, suggesting that there are at least two new distinct haplotypes corresponding to two distinct species. However, the specimens of each haplotype were microscopically indistinguishable from each other based on the gamont morphology, therefore, only a single species could be described and named, as Hemolivia pulcherrima n. sp. We consider that the uniform morphology of the most common blood stages of species of the genus Hemolivia complicates their differential diagnosis. Sequence divergence and different host spectra, therefore, remain the only differentiating tools.


Title: Espèces d'Hemolivia infectant les tortues peintes d'Amérique centrale (Rhinoclemmys pulcherrima manni) et problèmes de diagnostic différentiel au sein du genre Hemolivia. Abstract: Les parasites sanguins du genre Hemolivia Petit, Landau, Baccam et Lainson, 1990 (Adeleorina : Karyolysidae) sont des hémogrégarines de vertébrés ectothermes, tels que les lézards, les tortues et les crapauds. Seules cinq espèces d'Hemolivia provenant d'hôtes vertébrés et une de leur tique vectrice ont été décrites jusqu'à présent. Dans cette étude, des tortues peintes d'Amérique centrale (Rhinoclemmys pulcherrima manni) originaires du sud du Nicaragua ont été examinées pour détecter la présence d'hémogrégarines. Dix tortues sur 30 (33,3 %) étaient positives pour Hemolivia en utilisant les deux approches de microscopie et d'analyse de PCR. Les analyses phylogénétiques basées sur le gène de l'ARNr 18S ont révélé la présence de deux haplotypes, tous deux placés comme taxons frères dans le clade Hemolivia. Leur position phylogénétique était étayée par des valeurs de bootstrap et des probabilités postérieures élevées, suggérant qu'il existe au moins deux nouveaux haplotypes distincts correspondant à deux espèces distinctes. Cependant, les spécimens de chaque haplotype étaient impossibles à distinguer les uns des autres au microscope sur la base de la morphologie des gamontes. Par conséquent, une seule espèce a pu être décrite et nommée, comme Hemolivia pulcherrima n. sp. Nous considérons que l'uniformité de la morphologie des stades sanguins les plus courants des espèces du genre Hemolivia complique leur diagnostic différentiel. Les divergences de séquences et les différents spectres d'hôtes restent donc les seuls outils de différenciation.


Assuntos
Lagartos , Tartarugas , Animais , Filogenia , Diagnóstico Diferencial , Lagartos/parasitologia , América Central
8.
Infect Genet Evol ; 121: 105604, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38754756

RESUMO

Bats are known reservoirs of various emerging pathogens, and have recently been found to host a novel hantavirus, named Brno loanvirus (BRNV), from the Mammantavirinae subfamily (family Hantaviridae, order Bunyavirales). Here we report BRNV detection in bats from the urban area of Brno, Czech Republic in March 2022. Specifically, we uncovered a high prevalence of BRNV (8.8%, 5/57) among hibernating bats (Nyctalus noctula) in urban area, which poses a risk of human exposure. The positive bats included adult females (3/9 positive), a juvenile female (1/32 positive), and an adult male (1/6 positive). All 10 juvenile males were negative. We used RT-qPCR to quantify the BRNV RNA levels in various bat organs, which yielded positive results for viral RNA in organs, including the kidneys, heart, spleen, brain, liver, lung, and gut, and in body cavity fluid. Among all tested organs, the liver showed the highest levels of viral RNA in 4 out of 5 animals examined (average Ct value of 20.8 ± 7.4).


Assuntos
Quirópteros , Animais , República Tcheca/epidemiologia , Quirópteros/virologia , Feminino , Masculino , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Orthohantavírus/classificação , RNA Viral/genética , Filogenia , Reservatórios de Doenças/virologia , Infecções por Hantavirus/veterinária , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia
9.
Folia Parasitol (Praha) ; 702023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37565460

RESUMO

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, Jezková, Holubová, Sak, Konecný, Rost, McEvoy, Rajský et Kvác, 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.


Assuntos
Criptosporidiose , Cryptosporidium , Animais , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Sciuridae/parasitologia , Filogenia , Fezes/parasitologia , América do Norte
10.
Microbiol Spectr ; 10(5): e0130622, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36169417

RESUMO

Orthohantaviruses (genus Orthohantavirus) are a diverse group of viruses that are closely associated with their natural hosts (rodents, shrews, and moles). Several orthohantaviruses cause severe disease in humans. Central and western Europe are areas with emerging orthohantavirus occurrences. In our study, several orthohantaviruses, including the pathogenic Kurkino virus (KURV), were detected in their natural hosts trapped at several study sites in the Czech Republic. KURV was detected mainly in its typical host, the striped field mouse (Apodemus agrarius). Nevertheless, spillover infections were also detected in wood mice (Apodemus sylvaticus) and common voles (Microtus arvalis). Similarly, Tula virus (TULV) was found primarily in common voles, and events of spillover to rodents of other host species, including Apodemus spp., were recorded. In addition, unlike most previous studies, different tissues were sampled and compared to assess their suitability for orthohantavirus screening and possible tissue tropism. Our data suggest possible virus-specific tissue tropism in rodent hosts. TULV was most commonly detected in the lung tissue, whereas KURV was more common in the liver, spleen, and brain. Moreover, Seewis and Asikkala viruses were detected in randomly found common shrews (Sorex araneus). In conclusion, we have demonstrated the presence of human-pathogenic KURV and the potentially pathogenic TULV in their typical hosts as well as their spillover to atypical host species belonging to another family. Furthermore, we suggest the possibility of virus-specific tissue tropism of orthohantaviruses in their natural hosts. IMPORTANCE Orthohantaviruses (genus Orthohantavirus, family Hantaviridae) are a diverse group of globally distributed viruses that are closely associated with their natural hosts. Some orthohantaviruses are capable of infecting humans and causing severe disease. Orthohantaviruses are considered emerging pathogens due to their ever-increasing diversity and increasing numbers of disease cases. We report the detection of four different orthohantaviruses in rodents and shrews in the Czech Republic. Most viruses were found in their typical hosts, Kurkino virus (KURV) in striped field mice (Apodemus agrarius), Tula virus (TULV) in common voles (Microtus arvalis), and Seewis virus in common shrews (Sorex araneus). Nevertheless, spillover infections of atypical host species were also recorded for KURV, TULV, and another shrew-borne orthohantavirus, Asikkala virus. In addition, indications of virus-specific patterns of tissue tropism were observed. Our results highlight the circulation of several orthohantaviruses, including KURV, which is pathogenic to humans, among rodents and shrews in the Czech Republic.


Assuntos
Infecções por Hantavirus , Orthohantavírus , Animais , Humanos , Camundongos , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/veterinária , Musaranhos , República Tcheca/epidemiologia , Filogenia , Arvicolinae , Murinae , Tropismo
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