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The aim of this work was to evaluate the effect of pasteurization and coagulation during goat cheese production on the infectivity of Encephalitozoon cuniculi spores for immunodeficient (SCID, CD4-/-, and CD8-/-) and immunocompetent (BALB/c and C57BL/6) mice. Goat milk and fecal samples were screened for the presence and quantity of microsporidial DNA using molecular methods. Experimentally produced cheese from E. cuniculi-enriched goat milk or goat cheese purchased from retail producers was fed with experimental mice susceptible to E. cuniculi infection. The mice were sacrificed in the presumed acute phase of infection and samples of their tissues were subject to molecular detection of specific E. cuniculi DNA. Specific DNA of E. cuniculi genotype II was detected in feces and milk of three out of 99 goats kept on 6 farms in the Czech Republic. Under experimental conditions, spores of E. cuniculi genotype II remained viable in artificially enriched fresh cheese and were able to cause infection in laboratory mice. E. cuniculi genotype I and II DNA were detected in eight of the nine goat cheeses purchased from various producers/breeders in the Czech Republic and these cheeses were able to develop infection in both immunodeficient and immunocompetent mice. The results of these experiments showed that spores of E. cuniculi genotype I and II are able to remain viable after cheese processing and thus fresh and soft cheeses should be considered a potential source of microsporidia.

The diversity and biology ofCryptosporidiumthat is specific for rats (Rattusspp.) are not well studied. We examined the occurrence and genetic diversity ofCryptosporidiumspp. in wild brown rats (Rattus norvegicus) by microscopy and polymerase chain reaction (PCR)/sequencing targeting the small subunit rDNA (SSU), actin andHSP70 genes. Out of 343 faecal samples tested, none were positive by microscopy and 55 were positive by PCR. Sequence analysis ofSSUgene revealed the presence ofCryptosporidium muris(n= 4),C. andersoni(n= 3),C. ryanae(n= 1),C. occultus(n= 3),Cryptosporidiumrat genotype I (n= 23),Cryptosporidiumrat genotype IV (n= 16) and novelCryptosporidiumrat genotype V (n= 5). Spherical oocysts ofCryptosporidiumrat genotype I obtained from naturally-infected rats, measuring 4.4–5.4μm × 4.3–5.1μm, were infectious to the laboratory rats, but not to the BALB/c mice (Mus musculus) nor Mongolian gerbils (Meriones unguiculatus). The prepatent period was 3 days post infection and the patent period was longer than 30 days. Naturally- and experimentally-infected rats showed no clinical signs of disease. Percentage of nucleotide similarities at theSSU, actin,HSP70 loci betweenC. rattin. sp. and the rat derivedC. occultusandCryptosporidiumrat genotype II, III, IV, and V ranged from 91.0 to 98.1%. These genetic variations were similar or greater than that observed between closely related species, i.e.C. parvumandC. erinacei(93.2–99.5%). Our morphological, genetic and biological data support the establishment ofCryptosporidiumrat genotype I as a new species,Cryptosporidium rattin. sp.

Background Microsporidia of the genus Encephalitozoon are generally connected with severe infections with lethal outcome in immunodeficient hosts. In immunocompetent hosts, microsporidiosis typically establishes a balanced host-parasite relationship that produces minimal clinically overt disease. Although the alimentary tract represents one of the main primary target tissues, the mechanisms of reaching other tissues during systemic microsporidian infections remain unclear. Methods In the present study, we tested the relation between inflammation induction in immunocompetent and immunodeficient mice and the presence of spores of E. cuniculi genotype II in selected organs and in fecal specimens by using molecular and histology methods. Results We reported the positive connection between inflammation induction and the significant increase of E. cuniculi genotype II occurrence in inflammation foci in both immunocompetent BALB/c and immunodeficient severe combined immunodeficient (SCID) mice in the acute phase of infection and the re-activation of latent microsporidial infection following inflammation induction in immunocompetent mice. Conclusion The results imply possible involvement of immune cells serving as vehicles transporting E. cuniculi genotype II purposefully across the whole host body towards inflammation. With increasing number of records of infections, it is necessary to reconsider microsporidia as agents responsible for various pathologies. The elucidation of possible connection with pro-inflammatory immune responses represents an important challenge with consequences for human health and development of therapeutic strategies.

Bohumil Sak,1 Nikola Holubová,1 Dana Květoňová,1 Lenka Hlásková,1 Jana Tinavská,1,2 Marta Kicia,3 Żaneta Zajączkowska,3 Martin Kváč1,4 1Institute of Parasitology, Biology Centre, Czech Academy of Science, České Budějovice, Czech Republic; 2Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic; 3Department of Biology and Medical Parasitology, Wroclaw Medical University, Wroclaw, Poland; 4Faculty of Agriculture, University of South Bohemia in České Budějovice, České Budějovice, Czech RepublicCorrespondence: Bohumil Sak, Institute of Parasitology, Biology Centre, Czech Academy of Science, České Budějovice, Czech Republic, Tel +420387775421, Fax +420385310388, Email casio@paru.cas.czBackground: 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.Keywords: Encephalitozoon cuniculi genotype I, Encephalitozoon cuniculi genotype III, inflammation, targeted migration

Cryptosporidium spp. are common protozoan pathogens in mammals. The diversity and biology of Cryptosporidium in tree squirrels are not well studied. A total of 258 Eurasian red squirrels (Sciurus vulgaris) from 25 and 15 locations in the Czech Republic and Slovakia, respectively, were examined for Cryptosporidium spp. oocysts and specific DNA at the SSU, actin, HSP70, TRAP-C1, COWP, and gp60 loci. Out of 26 positive animals, only juveniles (9/12) were microscopically positive (18,000 to 72,000 OPG), and molecular analyses revealed the presence of Cryptosporidium sp. ferret genotype in all specimens. Oocysts obtained from naturally-infected squirrels measured 5.54–5.22 μm and were not infectious for laboratory mice (BALB/c and SCID), Mongolian gerbils, Guinea pigs, Southern multimammate mice, chickens, or budgerigars. None of naturally infected squirrels showed clinical signs of disease. The frequency of occurrence of the ferret genotype in squirrels did not vary statistically based on host age, gender or country of capture. Phylogenetic analysis of sequences from six loci revealed that Cryptosporidium sp. ferret genotype is genetically distinct from the currently accepted Cryptosporidium&nbsp, species. Morphological and biological data from this and previous studies support the establishment of Cryptosporidium sp. ferret genotype as a new species, Cryptosporidium&nbsp, sciurinum n. sp.

This study describes the prevalence and concentration of Encephalitozoon cuniculi spores in pork meat and evaluates the effect of sausage fermentation on E. cuniculi infectivity for immuno...

Cryptosporidiosis is a common parasitic infection in birds that is caused by more than 25 Cryptosporidium species and genotypes. Many of the genotypes that cause avian cryptosporidiosis are poorly characterized. The genetic and biological characteristics of avian genotype III are described here and these data support the establishment of a new species, Cryptosporidium proventriculi. Faecal samples from the orders Passeriformes and Psittaciformes were screened for the presence of Cryptosporidium by microscopy and sequencing, and infections were detected in 10 of 98 Passeriformes and in 27 of 402 Psittaciformes. Cryptosporidium baileyi was detected in both orders. Cryptosporidium galli and avian genotype I were found in Passeriformes, and C. avium and C. proventriculi were found in Psittaciformes. Cryptosporidium proventriculi was infectious for cockatiels under experimental conditions, with a prepatent period of six days post-infection (DPI), but not for budgerigars, chickens or SCID mice. Experimentally infected cockatiels shed oocysts more than 30 DPI, with an infection intensity ranging from 4,000 to 60,000 oocysts per gram (OPG). Naturally infected cockatiels shed oocysts with an infection intensity ranging from 2,000 to 30,000 OPG. Cryptosporidium proventriculi infects the proventriculus and ventriculus, and oocysts measure 7.4 × 5.8 μm. None of the birds infected C. proventriculi developed clinical signs.

Cryptosporidium spp., common parasites of vertebrates, remain poorly studied in wildlife. This study describes the novel Cryptosporidium species adapted to nutrias (Myocastor coypus). A total of 150 faecal samples of feral nutria were collected from locations in the Czech Republic and Slovakia and examined for Cryptosporidium spp. oocysts and specific DNA at the SSU, actin, HSP70, and gp60 loci. Molecular analyses revealed the presence of C. parvum (n = 1), C. ubiquitum subtype family XIId (n = 5) and Cryptosporidium myocastoris n. sp. XXIIa (n = 2), and XXIIb (n = 3). Only nutrias positive for C. myocastoris shed microscopically detectable oocysts, which measured 4.8–5.2 × 4.7–5.0 µm, and oocysts were infectious for experimentally infected nutrias with a prepatent period of 5–6 days, although not for mice, gerbils, or chickens. The infection was localised in jejunum and ileum without observable macroscopic changes. The microvilli adjacent to attached stages responded by elongating. Clinical signs were not observed in naturally or experimentally infected nutrias. Phylogenetic analyses at SSU, actin, and HSP70 loci demonstrated that C. myocastoris n. sp. is distinct from other valid Cryptosporidium species.

Parasites of the genus Cryptosporidium Tyzzer, 1910 are one of the most common protistan parasites of vertebrates. Faecal samples from 179 red foxes (Vulpes vulpes [Linnaeus]), 100 grey wolves (Canis lupus Linnaeus), 11 golden jackals (Canis aureus Linnaeus), and 63 brown bears (Ursus arctos Linnaeus) were collected in the Czech Republic, Poland and Slovakia. Samples were examined for the presence of Cryptosporidium spp. using microscopy and PCR/sequence analysis. Phylogenetic analysis based on the small subunit ribosomal RNA (SSU), actin and 60-kDa glycoprotein (gp60) genes using the maximum likelihood method revealed the presence of Cryptosporidium tyzzeri Ren, Zhao, Zhang, Ning, Jian et al., 2012 (n = 1) and C. andersoni Lindsay, Upton, Owens, Morgan, Mead et Blackburn, 2000 (n = 2) in red foxes, C. canis Fayer, Trout, Xiao, Morgan, Lai et Dubey, 2001 (n = 2) and C. ubiquitum Fayer, Santin et Macarisin, 2010 (n = 2) in grey wolves, and C. galli Pavlasek, 1999 in brown bears (n = 1) and red foxes (n = 1). Subtyping of isolates of C. ubiquitum and C. tyzzeri based on sequence analysis of gp60 showed that they belong to the XIId and IXa families, respectively. The presence of specific DNA of C. tyzzeri, C. andersoni and C. galli, which primarily infect the prey of carnivores, is probably the result of their passage through the gastrointestinal tract of the carnivores. Finding C. ubiquitum XIId in wolves may mean broadening the host spectrum of this subtype, but it remains possible this is the result of infected prey passing through the wolf - in this case deer, which is a common host of this parasite. The dog genotype of C. canis was reported for the first time in wolves.

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.

Encephalitozoon cuniculi genotype III disseminated intensively into most of the organs in all strains of mice, followed by a chronic infection with massive microsporidia persistence in immunodeficient mice and a partial decrease in C57Bl/6 mice. Treatment with 0.2 mg Albendazole/mouse/day temporarily reduces the number of affected organs in immunocompetent C57Bl/6 mice, but not in CD4-/- and CD8-/- mice. The application of medication temporarily decreased the spore burden at least by one order of magnitude in all groups. These results demonstrate that the E. cuniculi genotype III infection had a progressive course and surprisingly, Albendazole treatment had only a minimal effect. The E. cuniculi genotype III spore burden in individual organs reached up to 108 or 109 in immunocompetent or immunodeficient mice, respectively; however, these mice did not demonstrate any obvious clinical signs of microsporidiosis, and the immunodeficient mice survived longer. Our findings clearly show that the survival of mice does not correspond to spore burden, which provides new insight into latent microsporidiosis from an epidemiological point of view.

Fecal samples from wild-caught common voles (n= 328) from 16 locations in the Czech Republic were screened forCryptosporidiumby microscopy and PCR/sequencing at loci coding small-subunit rRNA,Cryptosporidiumoocyst wall protein, actin and 70 kDa heat shock protein.Cryptosporidiuminfections were detected in 74 voles (22.6%). Rates of infection did not differ between males and females nor between juveniles and adults. Phylogenetic analysis revealed the presence of eightCryptosporidiumspecies/genotypes including two new species,C. alticolisandC. microti. These species from wild-caught common voles were able to infect common and meadow voles under experimental conditions, with a prepatent period of 3–5 days post-infection (DPI), but they were not infectious for various other rodents or chickens. Meadow voles lost infection earlier than common voles (11–14vs13–16 DPI) and had significantly lower infection intensity.Cryptosporidium alticolisinfects the anterior small intestine and has larger oocysts (5.4 × 4.9µm), whereasC. microtiinfects the large intestine and has smaller oocysts (4.3 × 4.1µm). None of the rodents developed clinical signs of infection. Genetic and biological data support the establishment ofC. alticolisandC. microtias separate species of the genusCryptosporidium.

This study investigated the prevalence of Cryptosporidium in farmed fur animals in the Czech Republic and Poland. A total of 480 faecal samples were collected from fur animals, including 300 American mink (Mustela vison), 60 silver foxes (Vulpes vulpes), 50 long-tailed chinchillas (Chinchilla lanigera), and 70 nutrias (Myocastor coypus), at 14 farms. Samples were examined for the presence of Cryptosporidium using microscopy (following aniline-carbol-methyl violet staining) and sequence analysis of PCR amplified products. Three mink and two chinchillas from two different farms tested positive for Cryptosporidium ubiquitum DNA. The presence of C. ubiquitum DNA was not associated with diarrhoea. Subtyping of C. ubiquitum isolates by sequence analysis of the 60-kDa glycoprotein gene showed that isolates belonged to the XIIa subtype family, which was previously restricted to humans and ruminants. This suggests that C. ubiquitum subtype XIIa has a broader host range than previously reported.

Cryptosporidium is a genus of apicomplexan parasites that inhabit the respiratory and gastrointestinal tracts of vertebrates. Research of these parasites is limited by a lack of model hosts. This study aimed to determine the extent to which infection at the embryo stage can enhance the propagation of Cryptosporidium oocysts in chickens. Nine-day-old chicken embryos and one-day-old chickens were experimentally infected with different doses of Cryptosporidium baileyi and Cryptosporidium parvum oocysts. Post hatching, all chickens had demonstrable infections, and the infection dose had no effect on the course of infection. Chickens infected as embryos shed oocysts immediately after hatching and shed significantly more oocysts over the course of the infection than chickens infected as one-day-olds. In chickens infected as embryos, C. baileyi was found in all organs except the brain whereas, C. parvum was only found in the gastrointestinal tract and trachea. In chickens infected as one-day-olds, C. baileyi was only found in the gastrointestinal tract and trachea. Chickens infected as embryos with C. baileyi died within 16 days of hatching. All other chickens cleared the infection. Infection of chickens as embryos could be used as an effective and simple model for the propagation of C. baileyi and C. parvum.

Out of three genotypes of Encephalitozoon cuniculi (I-III) available for experimental studies, E. cuniculi genotype I remains the less characterized. This study describes for the first time individual phases of microsporidiosis caused by E. cuniculi genotype I and efficacy of albendazole treatment in immunocompetent BALB/c and C57Bl/6 mice and immunodeficient SCID, CD4-/- and CD8-/- mice using molecular detection and quantification methods. We demonstrate asymptomatic infection despite an intense dissemination of microsporidia into most organs within the first weeks post infection, followed by a chronic infection characterized by significant microsporidia persistence in immunocompetent, CD4-/- and CD8-/- mice and a lethal outcome for SCID mice. Albendazole application led to loss E. cuniculi genotype I infection in immunocompetent mouse strains, decreased spore burden by half in CD4-/- and CD8-/- mice, and prolongation of survival of SCID mice. These results showed Encephalitozoon cuniculi genotype I infection extend and albendazole sensitivity was comparable to E. cuniculi genotype II, but the infection onset speed and mortality rate was similar to E. cuniculi genotype III. These imply that differences in the course of infection and the response to treatment depend not only on immunological status of the host, but also on the genotype causing the infection.

This study describes the prevalence and concentration of

The morphological, biological, and molecular characteristics of Cryptosporidium avian genotype V are described, and the species name Cryptosporidium avium is proposed to reflect its specificity for birds under natural and experimental conditions. Oocysts of C. avium measured 5.30–6.90 μm (mean = 6.26 μm) × 4.30–5.50 μm (mean = 4.86 μm) with a length to width ratio of 1.29 (1.14–1.47). Oocysts of C. avium obtained from four naturally infected red-crowned parakeets (Cyanoramphus novaezealandiae) were infectious for 6-month-old budgerigars (Melopsittacus undulatus) and hens (Gallus gallus f. domestica). The prepatent periods in both susceptible bird species was 11 days post infection (DPI). The infection intensity of C. avium in budgerigars and hens was low, with a maximum intensity of 5,000 oocysts per gram of faeces. Oocysts of C. avium were microscopically detected at only 12–16 DPI in hens and 12 DPI in budgerigars, while PCR analyses revealed the presence of specific DNA in faecal samples from 11 to 30 DPI (the conclusion of the experiment). Cryptosporidium avium was not infectious for 8-week-old SCID and BALB/c mice (Mus musculus). Naturally or experimentally infected birds showed no clinical signs of cryptosporidiosis and no pathology was detected. Developmental stages of C. avium were detected in the ileum and caecum using scanning electron microscopy. Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. avium is genetically distinct from previously described Cryptosporidium species.

Host- and age-specificity of Cryptosporidium avium were studied in 1-, 21- and 365-day-old chickens (Gallus gallus), domestic ducks (Anas platyrhynchos) and ring-necked pheasants (Phasianus colchicus) under experimental conditions. Cryptosporidium avium was not infectious for ring-necked pheasants, but it was infectious for ducks and chickens at all age categories. The course of infection in ducks did not differ among age categories, but 365-day-old chickens had less severe infections than 1- and 21-day-old chickens. The patent period in chickens and ducks was >30 DPI, but ducks started to shed oocysts of C. avium earlier (5-6 DPI) and at a lower intensity (accumulated value of infection intensity of 58,000-65,000 OPG) than chickens (9-11 DPI and accumulated value of infection intensity of 100,000-105,000 OPG). Experimentally infected birds showed no clinical signs of cryptosporidiosis.

Faecal samples were collected from cats kept as pets (n = 120) and stray cats (n = 135) in Central Europe (Czech Republic, Poland and Slovakia) and screened for the presence of Cryptosporidium spp., Giardia intestinalis (Kunstler, 1882), Encephalitozoon spp. and Enterocytozoon bieneusi Desportes, Le Charpentier, Galian, Bernard, Cochand-Priollet, Lavergne, Ravisse et Modigliani, 1985 by PCR analysis of the small-subunit of rRNA (Cryptosporidium spp. and G. intestinalis) and ITS (microsporidia) genes. Sequence analysis of targeted genes revealed the presence of C. felis Iseki, 1979, G. intestinalis assemblage F, E. cuniculi Levaditi, Nicolau et Schoen, 1923 genotype II, and E. bieneusi genotype D. There was no correlation between the occurrence of detected parasites and sex, presence of diarrhoea or drug treatment (drug containing pyrantel and praziquantel). Compared to pet cats (7%), stray cats (30%) were statistically more frequently infected with protist parasites and overall may present a greater risk to human health.

A total of 345 faecal samples were collected from domestic, captive and wild birds in rural areas, urban areas and a Zoo in Algeria. Samples were screened for the presence of parasites belonging to the genus Cryptosporidium Tyzzer, 1910 by microscopy and PCR analysis of the small-subunit rRNA (SSU), actin and 60-kDa glycoprotein (gp60) genes. Cryptosporidium spp. were detected in 31 samples. Sequence analysis of SSU and actin genes revealed the presence of C. baileyi Current, Upton et Haynes, 1986 in domestic chicken broilers (n = 12), captive ostriches (n = 4) and a wild mallard (n = 1), and C. meleagridis Slavin, 1955 in a graylag goose (n = 1), chickens (n = 11) and turkeys (n = 2). Twenty-three chicken and two turkey broilers from five farms were positive for cryptosporidia, with an overall prevalence of 2% and 6%, respectively. Both C. meleagridis and C. baileyi were detected in farmed chicken broilers, with a prevalence ranging from 9% to 69%. Farmed turkeys broilers were positive only for C. meleagridis, with a 13% prevalence at the animal level. Subtyping of C. meleagridis isolates at the gp60 locus showed the presence of subtype IIIgA22G3R1 in graylag goose and chicken broilers and IIIgA23G2R1 in chicken and turkey broilers. Infection with cryptosporidia was not associated with any clinical diseases. The results of the present study, which provides the first data on the prevalence of Cryptosporidium spp. in wild birds in Africa, demonstrate the presence of human pathogenic C. meleagridis in both domestic and wild birds in Algeria.

Proventriculus and intestinal samples from 70 North American red-winged blackbirds (Agelaius phoeniceus; order Passeriformes) were examined for the presence of Cryptosporidium by PCR amplification and sequence analysis of the 18S ribosomal RNA (18S rRNA), actin, and 70-kDa heat shock protein (HSP70) genes. Twelve birds (17.1 %) were positive for the Cryptosporidium 18S rRNA gene: six birds were positive at the proventriculus site only and six birds were positive at the proventriculus and intestinal sites. Sequence analysis of the 18S rRNA, actin and HSP70 genes showed the presence of the gastric species Cryptosporidium galli in a single proventriculus sample and a closely related genotype, which we have named Cryptosporidium avian genotype VI, in all other positive samples. These findings contribute to our understanding of Cryptosporidium diversification in passerines, the largest avian order.