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Lihua Xiao - One of the best experts on this subject based on the ideXlab platform.
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annotated draft genome sequences of three species of Cryptosporidium Cryptosporidium meleagridis isolate ukmel1 c baileyi isolate tamu 09q1 and c hominis isolates tu502_2012 and ukh1
Pathogens and Disease, 2016Co-Authors: Olukemi O Ifeonu, Lihua Xiao, Kristin Elwin, Rachel M. Chalmers, Marcus C Chibucos, Joshua Orvis, Fengguang Guo, Haili Zhang, Mingfei Sun, Claire M FraserAbstract:Human cryptosporidiosis is caused primarily by Cryptosporidium hominis , C. parvum and C. meleagridis. To accelerate research on parasites in the genus Cryptosporidium , we generated annotated, draft genome sequences of human C. hominis isolates TU502_2012 and UKH1, C. meleagridis UKMEL1, also isolated from a human patient, and the avian parasite C. baileyi TAMU-09Q1. The annotation of the genome sequences relied in part on RNAseq data generated from the oocyst stage of both C. hominis and C. baileyi . The genome assembly of C. hominis is significantly more complete and less fragmented than that available previously, which enabled the generation of a much-improved gene set for this species, with an increase in average gene length of 500 bp relative to the protein-encoding genes in the 2004 C. hominis annotation. Our results reveal that the genomes of C. hominis and C. parvum are very similar in both gene density and average gene length. These data should prove a valuable resource for the Cryptosporidium research community.
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population genetics of Cryptosporidium meleagridis in humans and birds evidence for cross species transmission
International Journal for Parasitology, 2014Co-Authors: Yuanfei Wang, Yaoyu Feng, Lin Wang, Vitaliano Cama, Caryn Bern, Robert H Gilman, Wenli Yang, Lilia Cabrera, Ynes R Ortega, Lihua XiaoAbstract:Population genetic studies have been used to understand the transmission of pathogens in humans and animals, especially the role of zoonotic infections and evolution and dispersal of virulent subtypes. In this study, we analysed the genetic diversity and population structure of Cryptosporidium meleagridis, the only known Cryptosporidium species that infects both avian and mammalian hosts and is responsible for approximately 10% of human cryptosporidiosis in some areas. A total of 62 C. meleagridis specimens from children, AIDS patients, and birds in Lima, Peru were characterised by sequence analysis of the ssrRNA gene and five minisatellite, microsatellite and polymorphic markers in chromosome 6, including the 60 kDa glycoprotein (gp60), 47 kDa glycoprotein (CP47), a serine repeat antigen (MSC6-5), retinitis pigmentosa GTPase regulator (RPGR) and thrombospondin protein 8 (TSP8). The multilocus sequence analysis identified concurrent infections with Cryptosporidium hominis in four AIDS patients and three children. Unique subtypes of C. meleagridis ranged from eight at the gp60 locus (gene diversity -Hd=0.651), three at the RPGR (Hd=0.556), three at the MSC6-5 locus (Hd=0.242), two at TSP8 (Hd=0.198), to one at CP47 (monomorphic), much lower than that of C. hominis in the same area. Intragenic linkage disequilibrium was strong and complete at all gene loci. Intergenic linkage disequilibrium was highly significant (P<0.001) for all pairs of polymorphic loci. Two major groups of subtypes were seen, with most subtypes belonging to group 1. Within group 1, there was no clear population segregation, and two of the 14 multilocus subtypes of C. meleagridis were found in both AIDS patients and birds. We believe that these results provide the first evidence of a clonal population structure of C. meleagridis and the likely occurrence of cross-species transmission of C. meleagridis between birds and humans.
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common occurrence of zoonotic pathogen Cryptosporidium meleagridis in broiler chickens and turkeys in algeria
Veterinary Parasitology, 2013Co-Authors: Djamel Baroudi, Hongwei Zhang, Djamel Khelef, Rachid Goucem, Karim Tarik Adjou, Haileeyesus Adamu, Lihua XiaoAbstract:Only a small number of birds have been identified by molecular techniques as having Cryptosporidium meleagridis, the third most important species for human cryptosporidiosis. In this study, using PCR-RFLP analysis of the small subunit (SSU) rRNA gene, we examined the ileum of 90 dead chickens from 23 farms and 57 dead turkeys from 16 farms in Algeria for Cryptosporidium spp. C. meleagridis-positive specimens were subtyped by sequence analysis of the 60 kDa glycoprotein gene. Cryptosporidium infection rates were 34% and 44% in chickens and turkeys, respectively, with all positive turkeys (25) and most positive chickens (26/31) having C. meleagridis. All C. meleagridis specimens belonged to a new subtype family. The frequent occurrence of C. meleagridis in chickens and turkeys illustrates the potential for zoonotic transmission of cryptosporidiosis in Algeria.
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Zoonotic Cryptosporidium species and Enterocytozoon bieneusi genotypes in HIV-positive patients on antiretroviral therapy
Journal of clinical microbiology, 2012Co-Authors: Lin Wang, Longxian Zhang, Yaoyu Feng, Hongwei Zhang, Xudong Zhao, Guoqing Zhang, Meijin Guo, Lili Liu, Lihua XiaoAbstract:Molecular diagnostic tools have been used increasingly in the characterization of the transmission of cryptosporidiosis and microsporidiosis in developing countries. However, few studies have examined the distribution of Cryptosporidium species and Enterocytozoon bieneusi genotypes in AIDS patients receiving antiretroviral therapy. In the present study, 683 HIV-positive patients in the National Free Antiretroviral Therapy Program in China and 683 matched HIV-negative controls were enrolled. Cryptosporidium species and subtypes and Enterocytozoon bieneusi genotypes were detected and differentiated by PCR and DNA sequencing. The infection rates were 1.5% and 0.15% for Cryptosporidium and 5.7% and 4.2% for E. bieneusi in HIV-positive and HIV-negative participants, respectively. The majority (8/11) of Cryptosporidium cases were infections by zoonotic species, including Cryptosporidium meleagridis (5), Cryptosporidium parvum (2), and Cryptosporidium suis (1). Prevalent E. bieneusi genotypes detected, including EbpC (39), D (12), and type IV (7), were also potentially zoonotic. The common occurrence of EbpC was a feature of E. bieneusi transmission not seen in other areas. Contact with animals was a risk factor for both cryptosporidiosis and microsporidiosis. The results suggest that zoonotic transmission was significant in the epidemiology of both diseases in rural AIDS patients in China.
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multilocus sequence typing and genetic structure of Cryptosporidium hominis from children in kolkata india
Infection Genetics and Evolution, 2007Co-Authors: Wangeci Gatei, Vitaliano Cama, Pradeep Das, Phalguni Dutta, Abhik Sen, Altaf A Lal, Lihua XiaoAbstract:Abstract Endemicity of cryptosporidiosis in India has been documented with little genetic characterization of the parasites. Fifty Cryptosporidium-positive specimens collected between 2001 and 2004 from pediatric patients in Kolkata, India were analyzed for parasite genetic structure using multilocus sequence typing (MLST). Genotype analyses showed the presence of Cryptosporidium hominis, Cryptosporidium meleagridis and Cryptosporidium felis in 49, 2 and 1 patients, respectively (two patients had mixed infections of C. hominis and C. meleagridis). To assess the extent of genetic heterogeneity of C. hominis, minisatellites, microsatellites and polymorphic markers in three different chromosomes were sequenced, including genes encoding the 60 kDa glycoprotein (GP60), a 47 kDa protein (CP47), a mucin-like protein (Mucin1), a serine repeat antigen (MSC6-7), and a 56 kDa trans-membrane protein (CP56) in chromosome 6, the 70 kDa heat shock protein (HSP70) in chromosome 2, and a T-rich gene fragment (Chrom3T) in chromosome 3. Population sub-structure of C. hominis based on multilocus gene sequences showed that there were 25 multilocus subtypes defined by combined sequence length and nucleotide polymorphism, which formed four distinct groups in this population. Significant intra- and inter-genic linkage disequilibria were observed with minimum recombination or expansion of limited subtypes, all indicative of a mostly clonal population structure. The results highlight the importance of high resolution MLST in studying Cryptosporidium population sub-structure especially when length polymorphism may be inadequate in identifying unique subtypes. The significance of the diverse MLST within C. hominis in relation to geographical and temporal factors and clinical manifestations of disease warrants further investigations.
U M Morgan - One of the best experts on this subject based on the ideXlab platform.
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a multilocus genotypic analysis of Cryptosporidium meleagridis
Journal of Eukaryotic Microbiology, 2001Co-Authors: Scott Glaberman, Altaf A Lal, Irshad M Sulaiman, U M Morgan, Caryn Bern, Josef Levior, Michael M Peng, Robert H Gilman, Lihua XiaoAbstract:Cryptosporidium meleagridis is a common cause of cryptosporidiosis in birds. In addition, recent reports have described the parasite as an etiologic agent of cryptosporidiosis in both immunocompetent and immunocompromised humans. Therefore, it is important to genetically characterize isolates of C. meleagridis from different hosts and geographic areas, and to develop molecular tools to differentiate isolates from various hosts or areas. In this study, a total of 11 isolates of Cryptosporidium meleagridis from both human and avian hosts were examined at three genetic loci: the small-subunit rRNA, 60-kDa glycoprotein precursor, and 70-kDa heat shock protein genes. Two genotypes of C. meleagridis were seen at the small-subunit rRNA locus. These differed from each other by the presence or lack of a heterogeneous copy of the gene and an ATT repeat. The 60-kDa glycoprotein precursor gene divided these eleven isolates of C. meleagridis into six genotypes with high sequence diversity between groups. The highest genetic heterogeneity, however, was seen at the 70-kDa heat shock protein locus, and was primarily present at the 3′ end of the gene. This heterogeneity separated eight isolates of C. meleagridis into six genotypes. These data could be useful in the development of molecular tools to promote understanding of the transmission of C. meleagridis in humans.
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molecular and phylogenetic characterisation of Cryptosporidium from birds
International Journal for Parasitology, 2001Co-Authors: U M Morgan, Lihua Xiao, Irshad M Sulaiman, Shane Raidal, Josef Limor, Paul Monis, P J Odonoghue, Robin B Gasser, Allan Murray, Ronald FayerAbstract:Avian isolates of Cryptosporidium species from different geographic locations were sequenced at two loci, the 18S rRNA gene and the heat shock gene (HSP-70). Phylogenetic analysis of the sequence data provided support for the existence of a new avian species of Cryptosporidium infecting finches and a second species infecting a black duck. The identity of Cryptosporidium baileyi and Cryptosporidium meleagridis as valid species was confirmed. Also, C. baileyi was identified in a number of isolates from the brown quail extending the host range of this species.
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molecular characterization of Cryptosporidium isolates obtained from human immunodeficiency virus infected individuals living in switzerland kenya and the united states
Journal of Clinical Microbiology, 2000Co-Authors: U M Morgan, R C A Thompson, Lihua Xiao, Irshad M Sulaiman, Rainer Weber, W Ndiritu, A A Lal, A Moore, Peter DeplazesAbstract:A total of 22 Cryptosporidium isolates from human immunodeficiency virus-infected patients from Kenya, Switzerland, and the United States were examined at three genetic loci: the 18S ribosomal DNA, HSP-70, and acetyl coenzyme A synthetase genes. Four distinct Cryptosporidium genotypes were identified: (i) the Cryptosporidium parvum “human” genotype, (ii) the C. parvum “cattle” genotype, (iii) Cryptosporidium felis, and (iv) Cryptosporidium meleagridis. This is the first report of C. meleagridis in a human host. These results and those of others indicate that immunocompromised individuals are susceptible to a wide range of Cryptosporidium species and genotypes. Future studies are required to understand the full public health significance of Cryptosporidium genotypes and species in immunocompromised hosts.
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Cryptosporidium meleagridis in an indian ring necked parrot psittacula krameri
Australian Veterinary Journal, 2000Co-Authors: U M Morgan, Lihua Xiao, Ronald Fayer, A A Lal, Shane Raidal, Josef Limor, Stacey Gelis, Aileen Elliot, R C A ThompsonAbstract:Objective To perform a morphological and genetic characterisation of a Cryptosporidium infection in an Indian ring-necked parrot (Psittacula krameri) and to compare this with C meleagridis from a turkey. Design Tissue and intestinal sections from an Indian ring-necked parrot were examined microscopically for Cryptosporidium. The organism was also purified from the crop and intestine, the DNAextracted and a portion of the 18S rDNA gene amplified, sequenced and compared with sequence and biological information obtained for C meleagridis from a turkey as well as sequence information for other species of Cryptosporidium. Results Morphological examination of tissue sections from an Indian ring-necked parrot revealed large numbers of Cryptosporidium oocysts attached to the apical border of enterocytes lining the intestinal tract. Purified Cryptosporidium oocysts measured about 5.1 × 4.5 μm, which conformed morphologically to C meleagridis. The sequence obtained from this isolate was identical to sequence information obtained from a C meleagridis isolate from a turkey. ConclusionCryptosporidium meleagridis was detected in an Indian ring-necked parrot using morphological and molecular methods. This is the first time that this species of Cryptosporidium has been reported in a non-galliform host and extends the known host range of C meleagridis.
Robin B Gasser - One of the best experts on this subject based on the ideXlab platform.
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Cryptosporidium of birds in pet markets in wuhan city hubei china
Current Research in Parasitology & Vector-Borne Diseases, 2021Co-Authors: Cong Liao, Tao Wang, Anson V Koehler, Robin B GasserAbstract:Abstract Cryptosporidium is a group of protistan parasites of a range of vertebrates including mammals and birds. Stimulated by previous work that revealed “zoonotic” Cryptosporidium meleagridis subtypes (i.e. IIIbA26G1R1b and IIIbA22G1R1c) in diarrhoeic children and domestic chickens in Wuhan city and environs in Hubei Province, China, here we explored whether zoonotic C. meleagridis subtypes might also occur in pet birds in Wuhan city. From 11 bird markets in this city, we collected 322 faecal samples from 48 species of birds (representing six taxonomic orders), isolated genomic DNA and then conducted PCR-based sequencing of genetic markers in the small subunit (SSU) of the nuclear ribosomal RNA and the 60 kDa glycoprotein (gp60) genes of Cryptosporidium. Using SSU, Cryptosporidium was detected in 55 (17%) of the 322 samples. Cryptosporidium avium, C. baileyi, C. meleagridis, C. muris and C. proventriculi were characterised in 18%, 47%, 11%, 2% and 20% of the 55 samples, respectively, and a novel C. galli-like taxon in one sample. Using gp60, only one subtype (IIIeA17G2R1) of C. meleagridis was identified, which had not been detected in a previous study of diarrhoeic children in Wuhan. However, IIIe subtypes have been found in both humans and birds around the world. The relatively high prevalence and genetic diversity of Cryptosporidium recorded here in pet birds raise awareness about possible reservoirs of zoonotic variants of Cryptosporidium in birds in Wuhan, and potentially, other provinces in China.
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molecular investigation of Cryptosporidium in farmed chickens in hubei province china identifies zoonotic subtypes of c meleagridis
Parasites & Vectors, 2018Co-Authors: Cong Liao, Robin B Gasser, Tao Wang, Anson V Koehler, Yingying FanAbstract:Cryptosporidium is a key genus of parasitic protists that infect humans and other vertebrates (mammals and birds). Birds are typically infected with C. avium, C. baileyi, C. galli and/or C. meleagridis, the latter of which is recognised as being zoonotic. Stimulated by the previous finding of C. meleagridis subtypes IIIbA21G1R1, IIIbA22G1R1 and IIIbA26G1R1 in diarrhoeic children in Wuhan city and environs in Hubei Province, China, we performed a molecular epidemiological survey to explore whether these or similar subtypes might occur in farmed chickens in this province. PCR-coupled sequencing analyses of regions in the small subunit (SSU) of the nuclear ribosomal RNA and 60 kDa glycoprotein (gp60) genes were utilised to characterise Cryptosporidium in faecal samples from chickens (n = 471) from 14 farms from six distinct regions in Hubei Province. Cryptosporidium baileyi (33/471; 7.0%) and C. meleagridis (15/471; 3.2%) were identified in chickens on eight farms in five of the six distinct geographical regions. No significant age-associated difference in the prevalence of C. baileyi was evident, whereas the prevalence of C. meleagridis was significantly higher in younger (≤ 4 months) than in older chickens (> 4 months). For C. meleagridis, two subtype families, IIIb and IIIe, were defined; some of the subtypes (i.e. IIIbA26G1R1b and IIIbA22G1R1c) characterised here matched those identified previously in diarrhoeic children in Wuhan. This is the first molecular study reporting the genetic identity and prevalence of C. baileyi and C. meleagridis in chickens in Hubei. The findings suggest that C. meleagridis subtypes IIIbA26G1R1b and IIIbA22G1R1c are cross-transmissible between chickens and humans, raising awareness about the significance of birds as potential reservoirs of zoonotic variants of Cryptosporidium. Future studies might focus on investigating the prevalence of ‘zoonotic’ subtypes of Cryptosporidium meleagridis in various species of wild and domesticated birds, and on comparing them with those found in humans in China and other countries.
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Molecular investigation of Cryptosporidium in farmed chickens in Hubei Province, China, identifies ‘zoonotic’ subtypes of C. meleagridis
BMC, 2018Co-Authors: Cong Liao, Tao Wang, Anson V Koehler, Yingying Fan, Robin B GasserAbstract:Abstract Background Cryptosporidium is a key genus of parasitic protists that infect humans and other vertebrates (mammals and birds). Birds are typically infected with C. avium, C. baileyi, C. galli and/or C. meleagridis, the latter of which is recognised as being zoonotic. Stimulated by the previous finding of C. meleagridis subtypes IIIbA21G1R1, IIIbA22G1R1 and IIIbA26G1R1 in diarrhoeic children in Wuhan city and environs in Hubei Province, China, we performed a molecular epidemiological survey to explore whether these or similar subtypes might occur in farmed chickens in this province. Methods PCR-coupled sequencing analyses of regions in the small subunit (SSU) of the nuclear ribosomal RNA and 60 kDa glycoprotein (gp60) genes were utilised to characterise Cryptosporidium in faecal samples from chickens (n = 471) from 14 farms from six distinct regions in Hubei Province. Results Cryptosporidium baileyi (33/471; 7.0%) and C. meleagridis (15/471; 3.2%) were identified in chickens on eight farms in five of the six distinct geographical regions. No significant age-associated difference in the prevalence of C. baileyi was evident, whereas the prevalence of C. meleagridis was significantly higher in younger (≤ 4 months) than in older chickens (> 4 months). For C. meleagridis, two subtype families, IIIb and IIIe, were defined; some of the subtypes (i.e. IIIbA26G1R1b and IIIbA22G1R1c) characterised here matched those identified previously in diarrhoeic children in Wuhan. Conclusions This is the first molecular study reporting the genetic identity and prevalence of C. baileyi and C. meleagridis in chickens in Hubei. The findings suggest that C. meleagridis subtypes IIIbA26G1R1b and IIIbA22G1R1c are cross-transmissible between chickens and humans, raising awareness about the significance of birds as potential reservoirs of zoonotic variants of Cryptosporidium. Future studies might focus on investigating the prevalence of ‘zoonotic’ subtypes of Cryptosporidium meleagridis in various species of wild and domesticated birds, and on comparing them with those found in humans in China and other countries
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molecular and phylogenetic characterisation of Cryptosporidium from birds
International Journal for Parasitology, 2001Co-Authors: U M Morgan, Lihua Xiao, Irshad M Sulaiman, Shane Raidal, Josef Limor, Paul Monis, P J Odonoghue, Robin B Gasser, Allan Murray, Ronald FayerAbstract:Avian isolates of Cryptosporidium species from different geographic locations were sequenced at two loci, the 18S rRNA gene and the heat shock gene (HSP-70). Phylogenetic analysis of the sequence data provided support for the existence of a new avian species of Cryptosporidium infecting finches and a second species infecting a black duck. The identity of Cryptosporidium baileyi and Cryptosporidium meleagridis as valid species was confirmed. Also, C. baileyi was identified in a number of isolates from the brown quail extending the host range of this species.
Irshad M Sulaiman - One of the best experts on this subject based on the ideXlab platform.
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host adaptation and host parasite co evolution in Cryptosporidium implications for taxonomy and public health
International Journal for Parasitology, 2002Co-Authors: Lihua Xiao, Una Ryan, Ling Zhou, Irshad M Sulaiman, Edward R Atwill, Monica Lee Tischler, Xichen Zhang, Ronald Fayer, Altaf A LalAbstract:To assess the genetic diversity and evolution of Cryptosporidium parasites, the partial ssrRNA, actin, and 70 kDa heat shock protein (HSP70) genes of 15 new Cryptosporidium parasites were sequenced. Sequence data were analysed together with those previously obtained from other Cryptosporidium parasites (10 Cryptosporidium spp. and eight Cryptosporidium genotypes). Results of this multi-locus genetic characterisation indicate that host adaptation is a general phenomenon in the genus Cryptosporidium, because specific genotypes were usually associated with specific groups of animals. On the other hand, host-parasite co-evolution is also common in Cryptosporidium, as closely related hosts usually had related Cryptosporidium parasites. Results of phylogenetic analyses suggest that the Cryptosporidium parvum bovine genotype and Cryptosporidium meleagridis were originally parasites of rodents and mammals, respectively, but have subsequently expanded their host ranges to include humans. Understanding the evolution of Cryptosporidium species is important not only for clarification of the taxonomy of the parasites but also for assessment of the public health significance of Cryptosporidium parasites from animals.
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a multilocus genotypic analysis of Cryptosporidium meleagridis
Journal of Eukaryotic Microbiology, 2001Co-Authors: Scott Glaberman, Altaf A Lal, Irshad M Sulaiman, U M Morgan, Caryn Bern, Josef Levior, Michael M Peng, Robert H Gilman, Lihua XiaoAbstract:Cryptosporidium meleagridis is a common cause of cryptosporidiosis in birds. In addition, recent reports have described the parasite as an etiologic agent of cryptosporidiosis in both immunocompetent and immunocompromised humans. Therefore, it is important to genetically characterize isolates of C. meleagridis from different hosts and geographic areas, and to develop molecular tools to differentiate isolates from various hosts or areas. In this study, a total of 11 isolates of Cryptosporidium meleagridis from both human and avian hosts were examined at three genetic loci: the small-subunit rRNA, 60-kDa glycoprotein precursor, and 70-kDa heat shock protein genes. Two genotypes of C. meleagridis were seen at the small-subunit rRNA locus. These differed from each other by the presence or lack of a heterogeneous copy of the gene and an ATT repeat. The 60-kDa glycoprotein precursor gene divided these eleven isolates of C. meleagridis into six genotypes with high sequence diversity between groups. The highest genetic heterogeneity, however, was seen at the 70-kDa heat shock protein locus, and was primarily present at the 3′ end of the gene. This heterogeneity separated eight isolates of C. meleagridis into six genotypes. These data could be useful in the development of molecular tools to promote understanding of the transmission of C. meleagridis in humans.
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molecular and phylogenetic characterisation of Cryptosporidium from birds
International Journal for Parasitology, 2001Co-Authors: U M Morgan, Lihua Xiao, Irshad M Sulaiman, Shane Raidal, Josef Limor, Paul Monis, P J Odonoghue, Robin B Gasser, Allan Murray, Ronald FayerAbstract:Avian isolates of Cryptosporidium species from different geographic locations were sequenced at two loci, the 18S rRNA gene and the heat shock gene (HSP-70). Phylogenetic analysis of the sequence data provided support for the existence of a new avian species of Cryptosporidium infecting finches and a second species infecting a black duck. The identity of Cryptosporidium baileyi and Cryptosporidium meleagridis as valid species was confirmed. Also, C. baileyi was identified in a number of isolates from the brown quail extending the host range of this species.
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molecular characterization of Cryptosporidium isolates obtained from human immunodeficiency virus infected individuals living in switzerland kenya and the united states
Journal of Clinical Microbiology, 2000Co-Authors: U M Morgan, R C A Thompson, Lihua Xiao, Irshad M Sulaiman, Rainer Weber, W Ndiritu, A A Lal, A Moore, Peter DeplazesAbstract:A total of 22 Cryptosporidium isolates from human immunodeficiency virus-infected patients from Kenya, Switzerland, and the United States were examined at three genetic loci: the 18S ribosomal DNA, HSP-70, and acetyl coenzyme A synthetase genes. Four distinct Cryptosporidium genotypes were identified: (i) the Cryptosporidium parvum “human” genotype, (ii) the C. parvum “cattle” genotype, (iii) Cryptosporidium felis, and (iv) Cryptosporidium meleagridis. This is the first report of C. meleagridis in a human host. These results and those of others indicate that immunocompromised individuals are susceptible to a wide range of Cryptosporidium species and genotypes. Future studies are required to understand the full public health significance of Cryptosporidium genotypes and species in immunocompromised hosts.
Marianne Lebbad - One of the best experts on this subject based on the ideXlab platform.
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high applicability of a novel method for gp60 based subtyping of Cryptosporidium meleagridis
Journal of Clinical Microbiology, 2014Co-Authors: Christen Rune Stensvold, Jessica Beser, Charlotte Axen, Marianne LebbadAbstract:Cryptosporidium meleagridis is a common cause of cryptosporidiosis in avian hosts and the third most common species involved in human cryptosporidiosis. Sequencing of the highly polymorphic 60-kDa glycoprotein (gp60) gene is a frequently used tool for investigation of the genetic diversity and transmission dynamics of Cryptosporidium. However, few studies have included gp60 sequencing of C. meleagridis. One explanation may be that the gp60 primers currently in use are based on Cryptosporidium hominis and Cryptosporidium parvum sequence data, potentially limiting successful amplification of the C. meleagridis gp60 gene. We therefore aimed to design primers for better gp60 subtyping of C. meleagridis. Initially, ∼1,440 bp of the gp60 locus of seven C. meleagridis isolates were amplified using primers flanking the open reading frame. The obtained sequence data (∼1,250 bp) were used to design primers for a nested PCR targeting C. meleagridis. Twenty isolates (16 from human and 4 from poultry) previously identified as C. meleagridis by analysis of small subunit (SSU) rRNA genes were investigated. Amplicons of the expected size (∼900 bp) were obtained from all 20 isolates. The subsequent sequence analysis identified 3 subtype families and 10 different subtypes. The most common subtype family, IIIb, was identified in 12 isolates, represented by 6 subtypes, 4 new and 2 previously reported. Subtype family IIIe was found in 3 isolates represented by 3 novel, distinct subtypes. Finally, IIIgA31G3R1 was found in 1 human isolate and 4 poultry isolates, all originating from a previously reported C. meleagridis outbreak at a Swedish organic farm.
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zoonotic transmission of Cryptosporidium meleagridis on an organic swedish farm
International Journal for Parasitology, 2012Co-Authors: Charlotte Silverlas, Jens G Mattsson, Mona Insulander, Marianne LebbadAbstract:Abstract We believe that we present the first evidence of zoonotic transmission of the bird parasite, Cryptosporidium meleagridis. Despite being the third most common cause of human cryptosporidiosis, an identified zoonotic source has not been reported to date. We found Cryptosporidium oocysts in pigs, sheep/goats, hens and broiler chickens on a farm with suspected zoonotic transmission. By DNA analysis we identified C. meleagridis in samples from one human, three chickens and one hen. Sequencing of the ssrRNA and 70 kDa Heat Shock Protein (HSP) genes showed identical C. meleagridis sequences in the human and chicken samples, which is evidence of zoonotic transmission. The HSP70 sequence was unique.