The Eurasian beaver (Castor fiber) is an expanding species in Europe in recent decades due to reintroductions and natural population growth. Beavers expanded rapidly in the second half of the 20th century, and their expansion was particularly rapid in the Danube basin. Nowadays, the majority of the continuous population located in the central and eastern parts of the continent and a large disjunct population in Norway and Sweden. Despite the increasing population size, the role of the beaver as a source of waterborne pathogens is not firmly established or is often inferred from circumstantial data. In order to extend knowledge about the composition of the parasite fauna of beavers occurring in Slovakia, 21 faecal samples taken near their burrows from three sites (located in the Topľa, Poprad and Danube river basin) were examined microscopically and by polymerase chain reaction (PCR). PCR-positive specimens were further examined by DNA sequencing. Parasites were detected in 21% of the examined beavers, specifically the protozoa Cryptosporidium spp. (n = 2), Blastocystis sp. (n = 1), and microsporidia Enterocytozoon bieneusi (n = 1) and Encephalitozoon spp. (n = 1). Using the sequence analysis, two variants of Cryptosporidium proliferans, a new subtype of Blastocystis sp., genotype D of E. bieneusi and Encephalitozoon intestinalis were identified. A putatively novel Blastocystis subtype (ST), originated from a site near the Danube river (southwestern Slovakia), was proposed based on high genetic divergence from the closest described subtype ST12 (11.9%) and unique phylogenetic position in a clade composed of ST's 35-38. The increased risk of zoonotic transmission or transmission to other animals was particularly evident in the site near the Topľa river (northeastern Slovakia), where fungal spores of zoonotic genotype D of E. bieneusi and E. intestinalis, together with oocysts of the potentially zoonotic C. proliferans, were found.

• Klíčová slova
• Gastrointestinal parasites, Molecular analysis, Protected animals, Protozoan, Rodents, Zoonoses,
• Publikační typ
• časopisecké články MeSH

Microsporidia are pathogenic organism related to fungi. They cause infections in a wide variety of mammals as well as in avian, amphibian, and reptilian hosts. Many microsporidia species play an important role in the development of serious diseases that have significant implications in human and veterinary medicine. While microsporidia were originally considered to be opportunistic pathogens in humans, it is now understood that infections also occur in immune competent humans. Encephalitozoon cuniculi, Encephalitozoon intestinalis, and Enterocytozoon bieneusi are primarily mammalian pathogens. However, many other species of microsporidia that have some other primary host that is not a mammal have been reported to cause sporadic mammalian infections. Experimental models and observations in natural infections have demonstrated that microsporidia can cause a latent infection in mammalian hosts. This chapter reviews the published studies on mammalian microsporidiosis and the data on chronic infections due to these enigmatic pathogens.

• Klíčová slova
• Epidemiology, Infection, Latency, Mammals, Microsporidia, Recurrent infection, Transmission,
• MeSH
• Enterocytozoon * MeSH
• feces mikrobiologie   MeSH
• lidé MeSH
• Microsporidia * genetika   MeSH
• perzistentní infekce MeSH
• savci MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Microsporidia of the genus Encephalitozoon are usually associated with severe infections in immunodeficient hosts while, in immunocompetent ones, microsporidiosis produces minimal clinically apparent disease. Despite their microscopic size, microsporidia are capable of causing systemic infection within a few days. However, the mechanisms by which microsporidia reach target tissues during acute infection remain unclear. Out of four genotypes of Encephalitozoon cuniculi, only three are available for experimental studies, with E. cuniculi genotype II being the best characterized. METHODS: In the present study, we tested the association between inflammation induction in immunocompetent and immunodeficient mice and the presence of spores of E. cuniculi genotypes I and III in selected organs using molecular methods and compared the results with previously published data on E. cuniculi genotype II. RESULTS: We reported the positive connection between inflammation induction and the significant increase of E. cuniculi genotypes I and III occurrence in inflammatory foci in both immunocompetent BALB/c and immunodeficient severe combined immunodeficient (SCID) mice in the acute phase of infection. The induction of inflammation resulted in increased concentration of E. cuniculi of both genotypes in the site of inflammation, as previously reported for E. cuniculi genotype II. Moreover, our study extended the spectrum of differences among E. cuniculi genotypes by the variations in dispersal rate within host bodies after experimentally induced inflammation. CONCLUSION: The results imply possible involvement of immune cells serving as vehicles transporting E. cuniculi towards inflammation foci. The elucidation of possible connection with pro-inflammatory immune responses represents an important challenge with implications for human health and the development of therapeutic strategies.

• Klíčová slova
• Encephalitozoon cuniculi genotype I, Encephalitozoon cuniculi genotype III, inflammation, targeted migration,
• Publikační typ
• časopisecké články MeSH

The morphological, biological, and molecular characteristics of Cryptosporidium muris strain TS03 are described, and the species name Cryptosporidium proliferans n. sp. is proposed. Cryptosporidium proliferans obtained from a naturally infected East African mole rat (Tachyoryctes splendens) in Kenya was propagated under laboratory conditions in rodents (SCID mice and southern multimammate mice, Mastomys coucha) and used in experiments to examine oocyst morphology and transmission. DNA from the propagated C. proliferans isolate, and C. proliferans DNA isolated from the feces of an African buffalo (Syncerus caffer) in Central African Republic, a donkey (Equus africanus) in Algeria, and a domestic horse (Equus caballus) in the Czech Republic were used for phylogenetic analyses. Oocysts of C. proliferans are morphologically distinguishable from C. parvum and C. muris HZ206, measuring 6.8-8.8 (mean = 7.7 μm) × 4.8-6.2 μm (mean = 5.3) with a length to width ratio of 1.48 (n = 100). Experimental studies using an isolate originated from T. splendens have shown that the course of C. proliferans infection in rodent hosts differs from that of C. muris and C. andersoni. The prepatent period of 18-21 days post infection (DPI) for C. proliferans in southern multimammate mice (Mastomys coucha) was similar to that of C. andersoni and longer than the 6-8 DPI prepatent period for C. muris RN66 and HZ206 in the same host. Histopatologicaly, stomach glands of southern multimammate mice infected with C. proliferans were markedly dilated and filled with necrotic material, mucus, and numerous Cryptosporidium developmental stages. Epithelial cells of infected glands were atrophic, exhibited cuboidal or squamous metaplasia, and significantly proliferated into the lumen of the stomach, forming papillary structures. The epithelial height and stomach weight were six-fold greater than in non-infected controls. Phylogenetic analyses based on small subunit rRNA, Cryptosporidium oocyst wall protein, thrombospondin-related adhesive protein of Cryptosporidium-1, heat shock protein 70, actin, heat shock protein 90 (MS2), MS1, MS3, and M16 gene sequences revealed that C. proliferans is genetically distinct from C. muris and other previously described Cryptosporidium species.

• MeSH
• Cryptosporidium klasifikace   genetika   MeSH
• fylogeneze MeSH
• kryptosporidióza parazitologie   MeSH
• mikroftalmičtí podzemní hlodavci MeSH
• myši SCID MeSH
• myši MeSH
• oocysty metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH