PURPOSE: Parasites of genus Encephalitozoon are well known pathogens of domestic animals however less attention was paid to its spread among wildlife that can play an important role of reservoir of infection. The aim of the study was to conduct molecular detection and genotype characterization of Encephalitozoon spp. in wild small mammals trapped in localities both near to and at a large distance from residential areas. METHODS: In total, 300 wild small mammals (274 Rodentia and 26 Eulipotyphla) were trapped in 41 localities of the Czech Republic and tested by nested PCR for Encephalitozoon spp. RESULTS: The DNA of Encephalitozoon spp. was proved in tissues (brain or liver) of 11% (32/300) of animals. There was a statistically significant difference (p < 0.001) in positivity among animal species with the most infected species Micromys minutus (50%, 4/8) and Myodes glareolus (17%, 9/53). There was also statistically significant difference (p < 0.001) between localities with the higher positivity (29%, 12/42) in localities near to residential areas, compared to localities with a large distance from residential areas (8%, 20/258). Sex and age of wild small mammals did not have effect on their positivity. Genotyping analysis revealed E. cuniculi genotype II in 22 samples and E. hellem genotype 1 A in one sample. CONCLUSION: This study brings new information on the molecular characterization of Encephalitozoon spp. isolated from wild small mammals trapped in two different areas (localities in near to residential areas and localities with a large distance from residential areas).

• Klíčová slova
• Encephalitozoonosis, Genotyping, Urban area, Wildlife, Zoonosis,
• MeSH
• divoká zvířata * parazitologie   MeSH
• Encephalitozoon cuniculi genetika   izolace a purifikace   klasifikace   MeSH
• Encephalitozoon * genetika   izolace a purifikace   klasifikace   MeSH
• encephalitozoonóza * veterinární   epidemiologie   parazitologie   mikrobiologie   MeSH
• genotyp * MeSH
• hlodavci * parazitologie   MeSH
• hmyzožravci parazitologie   MeSH
• játra parazitologie   MeSH
• mozek parazitologie   MeSH
• polymerázová řetězová reakce MeSH
• zdroje nemoci * parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika 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

Of four genotypes of Encephalitozoon cuniculi, E. cuniculi genotype II is considered to represent a parasite that occurs in many host species in a latent asymptomatic form, whereas E. cuniculi genotype III seems to be more aggressive, and infections caused by this strain can lead to the death of even immunocompetent hosts. Although albendazole has been considered suitable for treatment of Encephalitozoon species, its failure in control of E. cuniculi genotype III infection has been reported. This study determined the effect of a 100× recommended daily dose of albendazole on an Encephalitozoon cuniculi genotype III course of infection in immunocompetent and immunodeficient mice and compared the results with those from experiments performed with a lower dose of albendazole and E. cuniculi genotype II. The administration of the regular dose of abendazole during the acute phase of infection reduced the number of affected organs in all strains of mice and absolute counts of spores in screened organs. However, the effect on genotype III was minor. Surprisingly, no substantial effect was recorded after the use of a 100× dose of albendazole, with larger reductions seen only in the number of affected organs and absolute counts of spores in all strains of mice, implying variations in albendazole resistance between these Encephalitozoon cuniculi genotypes. These results imply that differences in the course of infection and the response to treatment depend not only on the immunological status of the host but also on the genotype causing the infection. Understanding how microsporidia survive in hosts despite targeted antimicrosporidial treatment could significantly contribute to research related to human health.

• Klíčová slova
• Encephalitozoon cuniculi, albendazole, genotype III, microsporidiosis, tolerance, treatment,
• MeSH
• albendazol aplikace a dávkování   farmakologie   MeSH
• antifungální látky aplikace a dávkování   farmakologie   MeSH
• antigeny CD4 genetika   MeSH
• antigeny CD8 genetika   MeSH
• buněčné linie MeSH
• Cercopithecus aethiops MeSH
• Encephalitozoon cuniculi účinky léků   genetika   izolace a purifikace   MeSH
• encephalitozoonóza farmakoterapie   MeSH
• genotyp MeSH
• imunokompromitovaný pacient imunologie   MeSH
• mikrobiální testy citlivosti MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední BALB C MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• myši SCID MeSH
• myši MeSH
• počet mikrobiálních kolonií MeSH
• Vero buňky MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• albendazol MeSH
• antifungální látky MeSH
• antigeny CD4 MeSH
• antigeny CD8 MeSH

Encephalitozoon cuniculi is a model microsporidian species with a mononucleate nucleus and a genome that has been extensively studied. To date, analyses of genome diversity have revealed the existence of four genotypes in E. cuniculi (EcI, II, III and IV). Genome sequences are available for EcI, II and III, and are all very divergent, possibly diploid and genetically homogeneous. The mechanisms that cause low genetic diversity in E. cuniculi (for example, selfing, inbreeding or a combination of both), as well as the degree of genetic variation in their natural populations, have been hard to assess because genome data have been so far gathered from laboratory-propagated strains. In this study, we aim to tackle this issue by analyzing the complete genome sequence of a natural strain of E. cuniculi isolated in 2013 from a steppe lemming. The strain belongs to the EcIII genotype and has been designated EcIII-L. The EcIII-L genome sequence harbors genomic features intermediate to known genomes of II and III lab strains, and we provide primers that differentiate the three E. cuniculi genotypes using a single PCR. Surprisingly, the EcIII-L genome is also highly homogeneous, harbors signatures of heterozygosity and also one strain-specific single-nucleotide polymorphism (SNP) that introduces a stop codon in a key meiosis gene, Spo11. Functional analyses using a heterologous system demonstrate that this SNP leads to a deficient meiosis in a model fungus. This indicates that EcIII-L meiotic machinery may be presently broken. Overall, our findings reveal previously unsuspected genome diversity in E. cuniculi, some of which appears to affect genes of primary importance for the biology of this pathogen.

• MeSH
• Arvicolinae mikrobiologie   MeSH
• DNA fungální genetika   MeSH
• Encephalitozoon cuniculi genetika   MeSH
• genetická variace * MeSH
• genom fungální * MeSH
• genotyp MeSH
• heterozygot MeSH
• jednonukleotidový polymorfismus MeSH
• mapování chromozomů MeSH
• meióza MeSH
• sekvenční analýza DNA MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA fungální MeSH

Within the microsporidian genus Encephalitozoon, three species, Encephalitozoon cuniculi, Encephalitozoon hellem and Encephalitozoon intestinalis have been described. Several orders of the Class Aves (Passeriformes, Psittaciformes, Apodiformes, Ciconiiformis, Gruiformes, Columbiformes, Suliformes, Podicipediformes, Anseriformes, Struthioniformes, Falconiformes) and of the Class Mammalia (Rodentia, Lagomorpha, Primates, Artyodactyla, Soricomorpha, Chiroptera, Carnivora) can become infected. Especially E. cuniculi has a very broad host range while E. hellem is mainly distributed amongst birds. E. intestinalis has so far been detected only sporadically in wild animals. Although genotyping allows the identification of strains with a certain host preference, recent studies have demonstrated that they have no strict host specificity. Accordingly, humans can become infected with any of the four strains of E. cuniculi as well as with E. hellem or E. intestinalis, the latter being the most common. Especially, but not exclusively, immunocompromised people are at risk. Environmental contamination with as well as direct transmission of Encephalitozoon is therefore highly relevant for public health. Moreover, endangered species might be threatened by the spread of pathogens into their habitats. In captivity, clinically overt and often fatal disease seems to occur frequently. In conclusion, Encephalitozoon appears to be common in wild warm-blooded animals and these hosts may present important reservoirs for environmental contamination and maintenance of the pathogens. Similar to domestic animals, asymptomatic infections seem to occur frequently but in captive wild animals severe disease has also been reported. Detailed investigations into the epidemiology and clinical relevance of these microsporidia will permit a full appraisal of their role as pathogens.

• Klíčová slova
• Encephalitozoon cuniculi, Encephalitozoon intestinalis, Encephalitzoon hellem, Genotype, Reservoir, Zoonosis,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: Infectious diseases represent the greatest threats to endangered species, and transmission from humans to wildlife under increased anthropogenic pressure has been always stated as a major risk of habituation. AIMS: To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, one hundred mountain gorillas (Gorilla beringei beringei) from seven groups habituated either for tourism or for research in Volcanoes National Park, Rwanda were screened for the presence of microsporidia, Cryptosporidium spp. and Giardia spp. using molecular diagnostics. RESULTS: The most frequently detected parasites were Enterocytozoon bieneusi found in 18 samples (including genotype EbpA, D, C, gorilla 2 and five novel genotypes gorilla 4-8) and Encephalitozoon cuniculi with genotype II being more prevalent (10 cases) compared to genotype I (1 case). Cryptosporidium muris (2 cases) and C. meleagridis (2 cases) were documented in great apes for the first time. Cryptosporidium sp. infections were identified only in research groups and occurrence of E. cuniculi in research groups was significantly higher in comparison to tourist groups. No difference in prevalence of E. bieneusi was observed between research and tourist groups. CONCLUSION: Although our data showed the presence and diversity of important opportunistic protists in Volcanoes gorillas, the source and the routes of the circulation remain unknown. Repeated individual sampling, broad sampling of other hosts sharing the habitat with gorillas and quantification of studied protists would be necessary to acquire more complex data.

• MeSH
• Cryptosporidium klasifikace   genetika   izolace a purifikace   MeSH
• Encephalitozoon klasifikace   genetika   izolace a purifikace   MeSH
• encephalitozoonóza epidemiologie   mikrobiologie   MeSH
• fylogeneze MeSH
• Giardia klasifikace   genetika   izolace a purifikace   MeSH
• giardiáza epidemiologie   parazitologie   MeSH
• Hominidae MeSH
• intergenová DNA genetika   MeSH
• kryptosporidióza epidemiologie   parazitologie   MeSH
• molekulární sekvence - údaje MeSH
• nemoci lidoopů epidemiologie   mikrobiologie   parazitologie   MeSH
• veřejné parky MeSH
• zoonózy epidemiologie   mikrobiologie   parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Rwanda epidemiologie   MeSH
• Názvy látek
• intergenová DNA MeSH