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Lebbad M, Grüttner J, Beser J, Lizana V, Dea-Ayuela MA, Oropeza-Moe M, Carmena D, Stensvold CR. Complete sequencing of the Cryptosporidium suis gp60 gene reveals a novel type of tandem repeats-Implications for surveillance. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2024; 122:105614. [PMID: 38844191 DOI: 10.1016/j.meegid.2024.105614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/17/2024] [Accepted: 06/03/2024] [Indexed: 06/11/2024]
Abstract
Cryptosporidiosis is an infectious enteric disease caused by species (some of them zoonotic) of the genus Cryptosporidium that in many countries are under surveillance. Typing assays critical to the surveillance of cryptosporidiosis typically involve characterization of Cryptosporidium glycoprotein 60 genes (gp60). Here, we characterized the gp60 of Cryptosporidium suis from two samples-a human and a porcine faecal sample-based on which a preliminary typing scheme was developed. A conspicuous feature of the C. suis gp60 was a novel type of tandem repeats located in the 5' end of the gene and that took up 777/1635 bp (48%) of the gene. The C. suis gp60 lacked the classical poly-serine repeats (TCA/TCG/TCT), which is usually subject to major genetic variation, and the length of the tandem repeat made a typing assay incorporating this region based on Sanger sequencing practically unfeasible. We therefore designed a typing assay based on the post-repeat region only and applied it to C. suis-positive samples from suid hosts from Norway, Denmark, and Spain. We were able to distinguish three different subtypes; XXVa-1, XXVa-2, and XXVa-3. Subtype XXVa-1 had a wider geographic distribution than the other subtypes and was also observed in the human sample. We think that the present data will inform future strategies to develop a C. suis typing assay that could be even more informative by including a greater part of the gene, including the tandem repeat region, e.g., by the use of long-read next-generation sequencing.
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Affiliation(s)
- Marianne Lebbad
- Sjöbjörnsvägen, (formerly at the Department of Microbiology, Public Health Agency of Sweden, Solna, Sweden), Stockholm, Sweden
| | - Jana Grüttner
- European Programme for Public Health Microbiology Training (EUPHEM), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden; Laboratory of Parasitology, Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen S, Denmark
| | - Jessica Beser
- Department of Microbiology, Unit of Parasitology, Public Health Agency of Sweden, Solna, Sweden
| | - Victor Lizana
- Servicio de Análisis, Investigación y Gestión de Animales Silvestres (SAIGAS), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Valencia, Spain; Wildlife Ecology & Health Group (WE&H), Veterinary Faculty, Universitat Autònoma de Barcelona (UAB), Barcelona, Spain
| | - Maria Auxiliadora Dea-Ayuela
- Departamento de Farmacia, Facultad de Ciencias de la Salud, Universidad Cardenal Herrera-CEU, CEU Universities, Valencia, Spain
| | - Marianne Oropeza-Moe
- Department of Production Animal Clinical Sciences, Norwegian University of Life Sciences, Sandnes, Norway
| | - David Carmena
- Parasitology Reference and Research Laboratory, Spanish National Centre for Microbiology, Health Institute Carlos III, Majadahonda, Spain; CIBER Infectious Diseases (CIBERINFEC), Health Institute Carlos III, Madrid, Spain
| | - Christen Rune Stensvold
- Laboratory of Parasitology, Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen S, Denmark.
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El-Wakil ES, Abdelmaksoud HF, Wakid MH, Alsulami MN, Hammam O, Albohiri HH, Ghallab MMI. Annona muricata Leaf as an Anti-Cryptosporidial Agent: An In Silico Molecular Docking Analysis and In Vivo Studies. Pharmaceuticals (Basel) 2023; 16:878. [PMID: 37375825 DOI: 10.3390/ph16060878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/07/2023] [Accepted: 06/09/2023] [Indexed: 06/29/2023] Open
Abstract
Cryptosporidiosis is a serious parasitic diarrheal disease linked to the occurrence of colorectal cancer in immunocompromised patients. The FDA-approved drug nitazoxanide (NTZ) achieved a temporary effect, and relapses occur. Annona muricata leaf is widely used in traditional medicine to treat a wide range of disorders, including antiparasitic and anticancer effects. So, this study aimed to investigate Annona muricata leaf antiparasitic and anticancer properties compared to NTZ in Cryptosporidium parvum (C. parvum) acutely and chronically infected immunosuppressed mice. A molecular docking analysis was performed to evaluate the effectiveness of some biologically active compounds that represented the pharmacological properties of Annona muricata leaf-rich extract toward C. parvum lactate dehydrogenase compared to NTZ. For the in vivo study, eighty immunosuppressed albino mice were classified into four groups as follows: group I: infected and treated with A. muricata; group II: infected and treated with nitazoxanide; group III: infected and received no treatment; and group IV: were neither infected nor treated. Furthermore, half of the mice in groups I and II received the drugs on the 10th day post-infection (dpi), and the other half received treatment on the 90th day post-infection. Parasitological, histopathological, and immunohistochemical evaluations were performed. The docking analysis showed that the lowest estimated free energy of binding of annonacin, casuarine, L-epigallocatechin, P-coumaric acid, and ellagic acid toward C. parvum LDH, were -6.11, -6.32, -7.51, -7.81, and -9.64 kcal/mol, respectively, while NTZ was -7.03 kcal/mol. Parasitological examination displayed a significantly high difference in C. parvum oocyst mean counts in groups I and II compared to group III (p-value < 0.001), with group I demonstrating the highest efficacy. The analyses of histopathological and immunohistochemical results revealed that group I showed restoration of the normal villous pattern without evidence of dysplasia or malignancy. A. muricata leaf has proved to be a reliable agent for Cryptosporidium treatment. This paper argues for its promising use as an antiparasitic agent and for the prevention of neoplastic sequels of Cryptosporidium infection.
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Affiliation(s)
- Eman S El-Wakil
- Department of Parasitology, Theodor Bilharz Research Institute, Imbaba 12411, Egypt
| | - Hagar F Abdelmaksoud
- Department of Parasitology, Theodor Bilharz Research Institute, Imbaba 12411, Egypt
| | - Majed H Wakid
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Muslimah N Alsulami
- Department of Biology, College of Science, University of Jeddah, Jeddah 21589, Saudi Arabia
| | - Olfat Hammam
- Department of Pathology, Theodor Bilharz Research Institute, Imbaba 12411, Egypt
| | - Haleema H Albohiri
- Department of Biology, College of Science, University of Jeddah, Jeddah 21589, Saudi Arabia
| | - Marwa M I Ghallab
- Department of Medical Parasitology, Faculty of Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt
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Chen Y, Qin H, Wu Y, Xu H, Huang J, Li J, Zhang L. Global prevalence of Cryptosporidium spp. in pigs: a systematic review and meta-analysis. Parasitology 2023; 150:531-544. [PMID: 37051887 DOI: 10.1017/s0031182023000276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Cryptosporidium spp. are significant opportunistic pathogens causing diarrhoea in humans and animals. Pigs are one of the most important potential hosts for Cryptosporidium. We evaluated the prevalence of Cryptosporidium in pigs globally using published information and a random-effects model. In total, 131 datasets from 36 countries were included in the final quantitative analysis. The global prevalence of Cryptosporidium in pigs was 16.3% (8560/64 809; 95% confidence interval [CI] 15.0–17.6%). The highest prevalence of Cryptosporidium in pigs was 40.8% (478/1271) in Africa. Post-weaned pigs had a significantly higher prevalence (25.8%; 2739/11 824) than pre-weaned, fattening and adult pigs. The prevalence of Cryptosporidium was higher in pigs with no diarrhoea (12.2%; 371/3501) than in pigs that had diarrhoea (8.0%; 348/4874). Seven Cryptosporidium species (Cryptosporidium scrofarum, Cryptosporidium suis, Cryptosporidium parvum, Cryptosporidium muris, Cryptosporidium tyzzeri, Cryptosporidium andersoni and Cryptosporidium struthioni) were detected in pigs globally. The proportion of C. scrofarum was 34.3% (1491/4351); the proportion of C. suis was 31.8% (1385/4351) and the proportion of C. parvum was 2.3% (98/4351). The influence of different geographic factors (latitude, longitude, mean yearly temperature, mean yearly relative humidity and mean yearly precipitation) on the infection rate of Cryptosporidium in pigs was also analysed. The results indicate that C. suis is the dominant species in pre-weaned pigs, while C. scrofarum is the dominant species in fattening and adult pigs. The findings highlight the role of pigs as possible potential hosts of zoonotic cryptosporidiosis and the need for additional studies on the prevalence, transmission and control of Cryptosporidium in pigs.
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Affiliation(s)
- Yuancai Chen
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P. R. China
| | - Huikai Qin
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P. R. China
| | - Yayun Wu
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P. R. China
| | - Huiyan Xu
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P. R. China
| | - Jianying Huang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P. R. China
| | - Junqiang Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P. R. China
| | - Longxian Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P. R. China
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De Felice LA, Moré G, Cappuccio J, Venturini MC, Unzaga JM. Molecular characterization of Cryptosporidium spp. from domestic pigs in Argentina. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2020; 22:100473. [PMID: 33308753 DOI: 10.1016/j.vprsr.2020.100473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 09/15/2020] [Accepted: 09/18/2020] [Indexed: 10/23/2022]
Abstract
Cryptosporidiosis in pigs is caused by different Cryptosporidium species or genotypes, with C. suis and C. scrofarum considered porcine specific species. There is scarce information on Cryptosporidium infection in pigs in South America. A total of 520 individual faecal samples were obtained from 1, 2, 3 and 4 week old piglets (n = 130 from each age group), from 13 Argentinean intensive pig farms. The diagnosis of species of Cryptosporidium combined microscopy and molecular techniques. Genotyping from samples with Cryptosporidium oocysts at microscopy was performed by genus-specific and species-specific nested PCR targeting 18S rRNA gene fragments, and sequencing. Microscopic analysis detected Cryptosporidium oocysts in 47/520 (9%) faecal samples from 11/13 (85%) farms, with farm infection rates between 0 and 17.5%. Presence of Cryptosporidium oocysts was associated with diarrhea. The proportion of microscopically positive samples was not associated with piglet age. A total of 15/47 (32% of samples with oocyst compatible structures) were positive by genus and species-specific nested PCR. Species-specific PCR and sequencing showed presence of C. suis, C. scrofarum, and both species in 3, 8 and 4 samples, respectively. The proportion of positive samples on each specific PCR was similar between age groups, being C. suis proportion slightly higher in 4 week old piglets. The use of molecular tools allowed the confirmation of C. suis and C. scrofarum infection in Argentinean pigs. Cryptosporidiosis was widely distributed in the main pig husbandry area from Argentina, with a low to moderate intra farm infection rate.
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Affiliation(s)
- Lorena A De Felice
- Laboratorio de Inmunoparasitología (LAINPA), Flacultad de Ciencias Veterinarias, Universidad Nacional de La Plata, 60 y 118 (1900), La Plata, Argentina
| | - Gastón Moré
- Laboratorio de Inmunoparasitología (LAINPA), Flacultad de Ciencias Veterinarias, Universidad Nacional de La Plata, 60 y 118 (1900), La Plata, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917 (C1033AAJ), Buenos Aires, Argentina.
| | - Javier Cappuccio
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917 (C1033AAJ), Buenos Aires, Argentina; Estación Experimental Agropecuaria (EEA) Marcos Juarez, Instituto Nacional de Tecnología Agropecuaria (INTA), Ruta 12 Km.3 (2580), Marcos Juarez, Córdoba, Argentina
| | - María C Venturini
- Laboratorio de Inmunoparasitología (LAINPA), Flacultad de Ciencias Veterinarias, Universidad Nacional de La Plata, 60 y 118 (1900), La Plata, Argentina
| | - Juan M Unzaga
- Laboratorio de Inmunoparasitología (LAINPA), Flacultad de Ciencias Veterinarias, Universidad Nacional de La Plata, 60 y 118 (1900), La Plata, Argentina
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Pettersson E, Ahola H, Frössling J, Wallgren P, Troell K. Detection and molecular characterisation of Cryptosporidium spp. in Swedish pigs. Acta Vet Scand 2020; 62:40. [PMID: 32727527 PMCID: PMC7388442 DOI: 10.1186/s13028-020-00537-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/12/2020] [Indexed: 11/24/2022] Open
Abstract
Background Cryptosporidium is a genus of apicomplexan parasites that cause enteric disease in vertebrates. In pigs, infections are most often asymptomatic, but may result in diarrhoea and poor growth. The most common species detected in pigs are C. suis and C. scrofarum with low zoonotic potential. C. parvum, with higher zoonotic potential, may also be found. As previous knowledge on the occurrence of Cryptosporidium in Swedish pigs is scarce, this was investigated in our study. Faecal samples from 13 pig herds were collected and a total of 222 pooled pen samples, from suckling piglets (n = 48), growers, aged 6–12 weeks (n = 57), fatteners, aged 13–24 weeks (n = 67) and adult animals (n = 50) were included. Samples were analysed using microscopy and positive samples were further analysed using polymerase chain reaction and sequencing of the 18S rRNA gene and the 28S rRNA gene to determine species. Results Cryptosporidium spp. were detected in all sampled herds and in 25% (56/222) of the individual pen samples. Infections were most common in growers and fatteners with 51% (29/57) and 35% (20/67) positive samples in each group, respectively. The piglets had 8% (4/48) positive samples and adults had 6% (3/50). Species determination showed C. suis and C. scrofarum in piglets and growers, C. scrofarum in the fatteners, and C. suis and C. parvum in the adults. Although no mixed infections could be confirmed we saw signs of double peaks in the 28S rRNA gene chromatograms, possibly indicating more than one species present per sample. Conclusion Cryptosporidium spp. were detected on every sampled farm and in 25% of the individual pen samples in our study. We therefore conclude that Cryptosporidium spp. are present and likely common in Swedish pig herds, where pigs are loose and reared on solid floors. However, none of the farms reported any problems with poor weight gain, diarrhoea, or reduced appetite in their pig herds. The pig adapted C. suis and C. scrofarum were the predominant species identified. Two samples were positive for the more zoonotic C. parvum, and pigs should hence not be disregarded as a possible source of zoonotic cryptosporidiosis.
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Niine T, Dorbek-Kolin E, Lassen B, Orro T. Cryptosporidium outbreak in calves on a large dairy farm: Effect of treatment and the association with the inflammatory response and short-term weight gain. Res Vet Sci 2018; 117:200-208. [PMID: 29304439 PMCID: PMC7111845 DOI: 10.1016/j.rvsc.2017.12.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 11/23/2017] [Accepted: 12/26/2017] [Indexed: 02/06/2023]
Abstract
Cryptosporidium spp. infections in neonatal dairy calves can cause diarrhoea and, in rare cases, death. The infection is usually self-limiting, but halofuginone lactate (HL) can be used prophylactically. Calves (n=144) in the study were born during a 2-month period on one farm. A total of 901 serum and 767 faecal samples were collected. Based on HL treatment, the calves were divided into 3 groups: I) not treated, II) treated incorrectly (treatment started >48h after birth, or lasted <7days), and III) treated correctly (started <48h after birth, and lasted ≥7days). Over the 3-month observation period, 14.6% (n=21) of the calves died, of which most (67%) had not been treated with HL. Correctly performed treatment of cryptosporidiosis significantly delayed the onset of oocysts shedding (P<0.001) and reduced haptoglobin (HP) and serum amyloid A (SAA) concentrations in the second week of life. HP concentration and HL treatment were negatively associated with weight gain at 3months of age. Cryptosporidium positive faecal samples were significantly (P<0.001) more likely to be diarrhoeic but Giardia or Eimeria positive samples were not. Correct prophylactic treatment with HL delayed the shedding of Cryptosporidium oocysts and improved survival, but was negatively associated with weight gain. Incorrect treatment had a low impact on mortality and resembled no treatment regarding the proportion of calves shedding oocysts. Acute phase response (APR) in the second week of life seemed to be positively associated with shedding high amounts of Cryptosporidium oocysts.
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Affiliation(s)
- Tarmo Niine
- Institute of Veterinary Medicine and Animal Science, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu 51014, Estonia.
| | - Elisabeth Dorbek-Kolin
- Institute of Veterinary Medicine and Animal Science, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu 51014, Estonia
| | - Brian Lassen
- Institute of Veterinary Medicine and Animal Science, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu 51014, Estonia; Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Toomas Orro
- Institute of Veterinary Medicine and Animal Science, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu 51014, Estonia
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Schubnell F, von Ah S, Graage R, Sydler T, Sidler X, Hadorn D, Basso W. Occurrence, clinical involvement and zoonotic potential of endoparasites infecting Swiss pigs. Parasitol Int 2016; 65:618-624. [PMID: 27639842 PMCID: PMC7108367 DOI: 10.1016/j.parint.2016.09.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/12/2016] [Accepted: 09/13/2016] [Indexed: 11/30/2022]
Abstract
In order to estimate the diversity, clinical involvement and zoonotic potential of parasites in pigs submitted for diagnosis to the PathoPig project of the Swiss Federal Food Safety and Veterinary Office, faeces (n=125) from suckling piglets (n=39), weaners (n=60) and piglets beginning fattening (n=26) from 74 Swiss farms were examined by 3 coproscopical methods (i.e. sedimentation/zinc chloride-flotation; SAFC and Ziehl-Neelsen staining). Samples microscopically positive for Cryptosporidium were further tested by PCR/sequencing for species assessment. The most frequently detected parasite was Balantidium coli, a facultative pathogenic ciliate with zoonotic potential, in 5.1, 36.7 and 50.0% of suckling, weaners and fatteners and 43.2% of farms; however, no association with disease was observed. Isospora (syn. Cystoisospora) suis infections were detected in 13.3 and 11.1% of suckling piglets with and without diarrhoea, and in 10.0 and 13.3% of weaners and fatteners with diarrhoea, respectively, and were significant associated with emaciation. Cryptosporidium infections were detected in 10.3, 15.0 and 19.2% of sucklings, weaners and fatteners, respectively, and in 18.9% of the farms. Interestingly, two age-related species were identified: C. suis in younger piglets (2 to 6weeks) and C. scrofarum in older ones (6 to 17weeks). None of the pigs infected with C. scrofarum (n=8), but 3 of 4 piglets infected with C. suis (co-infection with I. suis in 2 cases) had diarrhoea. The zoonotic species C. parvum was not detected, nevertheless, sporadic cases of human infection with the porcine-adapted species have been reported. Ascaris suum, Trichuris suis and Strongylida were rarely detected (<4%) in all age categories.
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Affiliation(s)
- Fabienne Schubnell
- Institute of Parasitology, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 266a, CH-8057 Zurich, Switzerland
| | - Sereina von Ah
- Institute of Parasitology, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 266a, CH-8057 Zurich, Switzerland; Department of Farm Animals, Division of Swine Medicine, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland
| | - Robert Graage
- Department of Farm Animals, Division of Swine Medicine, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland; Institute of Veterinary Pathology, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 268, CH-8057 Zurich, Switzerland
| | - Titus Sydler
- Institute of Veterinary Pathology, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 268, CH-8057 Zurich, Switzerland
| | - Xaver Sidler
- Department of Farm Animals, Division of Swine Medicine, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland
| | - Daniela Hadorn
- Federal Food Safety and Veterinary Office, Schwarzenburgstrasse 155, CH-3003 Bern, Switzerland
| | - Walter Basso
- Institute of Parasitology, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 266a, CH-8057 Zurich, Switzerland; Department of Farm Animals, Division of Swine Medicine, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland.
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Petersen HH, Jianmin W, Katakam KK, Mejer H, Thamsborg SM, Dalsgaard A, Olsen A, Enemark HL. Cryptosporidium and Giardia in Danish organic pig farms: Seasonal and age-related variation in prevalence, infection intensity and species/genotypes. Vet Parasitol 2015; 214:29-39. [PMID: 26483166 DOI: 10.1016/j.vetpar.2015.09.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 09/08/2015] [Accepted: 09/18/2015] [Indexed: 11/15/2022]
Abstract
Although pigs are commonly infected with Cryptosporidium spp. and Giardia duodenalis, including potentially zoonotic species or genotypes, little is known about age-related infection levels, seasonal differences and genetic variation in naturally infected pigs raised in organic management systems. Therefore, the current study was conducted to assess seasonal and age-related variations in prevalence and infection intensity of Cryptosporidium and Giardia, evaluate zoonotic potential and uncover correlations between species/genotypes, infection intensity and faecal consistency. Shedding of oocysts and cysts ((oo-)cysts) was monitored at quarterly intervals (September 2011-June 2012) in piglets (n = 152), starter pigs (n = 234), fatteners (n = 230) and sows (n = 240) from three organic farms in Denmark. (oo-)Cysts were quantified by immunofluorescence microscopy; and 56/75 subsamples from Cryptosporidium infected pigs were successfully analysed by PCR amplification and partial sequencing of the small subunit (SSU) 18S rRNA and hsp70genes, while 13/67 Giardia subsamples were successfully analysed by amplification and partial sequencing of the 18S rRNA and the gdh genes. Altogether, Cryptosporidium or Giardia infections were observed in 40.9% (350/856) and 14.0% (120/856) of the pigs, respectively, including 8.2% (70/856) infected with both parasites. Prevalence, intensity of infections and presence of Cryptosporidium species varied significantly between age-groups; 53.3% piglets, 72.2% starter pigs, 40.4% fatteners and 2.9% sows were infected with Cryptosporidium, whereas 2.0% piglets, 27.4% starter pigs, 17.8% fatteners and 5.0% sows were infected with Giardia. The overall prevalence was stable throughout the year, except for dual-infections that were more prevalent in September and December (p < 0.05). The infection intensity was age-related for both parasites, and dual-infected pigs tended to excrete lower levels of oocysts compared to pigs harbouring only Cryptosporidium. Likewise, pigs infected with Cryptosporidium scrofarum excreted fewer oocysts (mean CPG: 54,848 ± 194,508CI: 9085-118,781) compared to pigs infected with Cryptosporidium suis (mean OPG: 351,035 ± 351,035CI: 67,953-634,117). No correlation between faecal consistency and (oo-)cyst excretion levels was observed. Of the successfully genotyped isolates, 38/56 (67.9%) were C. scrofarum and 18/56 (32.1%) were C. suis, while the livestock specific G. duodenalis Assemblage E was detected in 11/13 (84.6%) isolates and the potentially zoonotic Assemblage A was identified in 2/13 (15.4%) isolates. Piglets exclusively hosted C. suis, with one exception, while starter pigs and fatteners predominantly hosted C. scrofarum. As organic pigs are partly reared outdoors, environmental contamination with Cryptosporidium and Giardia is inevitable. Nevertheless, the present data indicate that the potential public health risk associated with both of these parasites in Danish organic pig production seems to be negligible.
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Affiliation(s)
- Heidi H Petersen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
| | - Wang Jianmin
- Shenyang Agricultural University, Shen Yang, People's Republic of China
| | - Kiran K Katakam
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Helena Mejer
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Stig M Thamsborg
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Anders Dalsgaard
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Annette Olsen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Heidi L Enemark
- Section for Bacteriology, Pathology and Parasitology, National Veterinary Institute, Technical University of Denmark, Frederiksberg, Denmark; Section for Parasitology, Norwegian Veterinary Institute, P.O. Box 750 Sentrum, NO-0106 Oslo, Norway
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Šlapeta J. Cryptosporidiosis and Cryptosporidium species in animals and humans: a thirty colour rainbow? Int J Parasitol 2013; 43:957-70. [PMID: 23973380 DOI: 10.1016/j.ijpara.2013.07.005] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 07/29/2013] [Accepted: 07/31/2013] [Indexed: 10/26/2022]
Abstract
Parasites of the genus Cryptosporidium (Apicomplexa) cause cryptosporidiosis in humans and animals worldwide. The species names used for Cryptosporidium spp. are confusing for parasitologists and even more so for non-specialists. Here, 30 named species of the genus Cryptosporidium are reviewed and proposed as valid. Molecular and experimental evidence suggests that humans and cattle are the hosts for 14 and 13 out of 30 named species, respectively. Two, four and eight named species are considered of major, moderate and minor public health significance, respectively. There are at least nine named species that are shared between humans and cattle. The aim of this review is to outline available species information together with the most commonly used genetic markers enabling the identification of named Cryptosporidium spp. Currently, 28 of 30 named species can be identified using the complete or partial ssrRNA, serving as a retrospective 'barcode'. Currently, the ssrRNA satisfies the implicit assumption that the reference databases used for comparison are sufficiently complete and applicable across the whole genus. However, due to unreliable annotation in public DNA repositories, the reference nucleotide entries and alignment of named Cryptosporidium spp. has been compiled. Despite its known limitations, ssrRNA remains the optimal marker for species identification.
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Affiliation(s)
- Jan Šlapeta
- Faculty of Veterinary Science, McMaster Building B14, University of Sydney, New South Wales 2006, Australia.
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Cacciò SM, Widmer G, Axén C, Fayer R. Cryptosporidiosis in Farmed Animals. CRYPTOSPORIDIUM: PARASITE AND DISEASE 2013. [PMCID: PMC7122230 DOI: 10.1007/978-3-7091-1562-6_4] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Cryptosporidiosis was first identified as a disease of veterinary, rather than human medical, importance, and infection of farmed animals with different species of Cryptosporidium continues to be of veterinary clinical concern. This chapter provides insights into Cryptosporidium infection in a range of farmed animals – cattle, sheep, goats, pigs, cervids, camelids, rabbits, water buffalo and poultry – presenting not only an updated overview of the infection in these animals, but also information on clinical disease, infection dynamics and zoonotic potential. Although extensive data have been accrued on, for example, Cryptosporidium parvum infection in calves, and calf cryptosporidiosis continues to be a major veterinary concern especially in temperate regions, there remains a paucity of data for other farmed animals, despite Cryptosporidium infection causing significant clinical disease and also, for some species, with the potential for transmission of infection to people, either directly or indirectly.
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Affiliation(s)
- Simone M. Cacciò
- Department of Infectious, Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Giovanni Widmer
- Tufts Cummings School of Veterinary Medicine Division of Infectious Diseases, North Grafton, Massachusetts USA
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Zhang W, Yang F, Liu A, Wang R, Zhang L, Shen Y, Cao J, Ling H. Prevalence and genetic characterizations of Cryptosporidium spp. in pre-weaned and post-weaned piglets in Heilongjiang Province, China. PLoS One 2013; 8:e67564. [PMID: 23844032 PMCID: PMC3701062 DOI: 10.1371/journal.pone.0067564] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 05/20/2013] [Indexed: 11/25/2022] Open
Abstract
Background Cryptosporidium spp. are common intestinal protozoa of humans and animals. There have been few studies conducted on the molecular characterizations of pig-derived Cryptosporidium isolates worldwide, especially in China. Thus, the aim of the present study was to understand the prevalence, distribution and genotypes of Cryptosporidium in pigs in Heilongjiang Province, China. Methodology/Principal Findings A total of 568 fecal samples from pre-weaned and post-weaned piglets were collected from eight pig farms from four areas of Heilongjiang Province. The average infection rate of Cryptosporidium was 1.6% (9/568) by microscopy. 113 samples were subjected to PCR amplification of the small subunit (SSU) rRNA gene of Cryptosporidium, with 55.8% (63/113) being positive for Cryptosporidium. Cryptosporidium suis (n = 31) and C. scrofarumn (n = 32) were identified by DNA sequencing of the SSU rRNA gene. Three types of C. scrofarumn were found at the SSU rRNA locus, with one novel type being detected. Using species/genotype-specific primers for pig-adapted Cryptosporidium spp., 22 and 23 respectively belonged to C. suis and C. scrofarum mono-infections, with 18 co-infections detected. The infection peaks for C. suis (60%, 24/40) and C. scrofarum (51.2%, 21/41) were respectively found in the piglets of 5 to 8 weeks and more than 8 weeks. Conclusion/Significance The detection of C. suis and C. scrofarum in pre-weaned and post-weaned piglets has public health implications, due to the fact that the two species are both zoonotic Cryptosporidium. The novel C. scrofarum type detected may be endemic to China.
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Affiliation(s)
- Weizhe Zhang
- Department of Parasitology, Harbin Medical University, Harbin, Heilongjiang, China
| | - Fengkun Yang
- Department of Parasitology, Harbin Medical University, Harbin, Heilongjiang, China
| | - Aiqin Liu
- Department of Parasitology, Harbin Medical University, Harbin, Heilongjiang, China
- * E-mail: (AL); (HL)
| | - Rongjun Wang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University Zhengzhou, Henan, China
| | - Longxian Zhang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University Zhengzhou, Henan, China
| | - Yujuan Shen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology, Ministry of Health, World Health Organization Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, China
| | - Jianping Cao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology, Ministry of Health, World Health Organization Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, China
| | - Hong Ling
- Department of Parasitology, Harbin Medical University, Harbin, Heilongjiang, China
- * E-mail: (AL); (HL)
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Keidel J, Daugschies A. Integration of halofuginone lactate treatment and disinfection with p-chloro-m-cresol to control natural cryptosporidiosis in calves. Vet Parasitol 2013; 196:321-6. [PMID: 23561324 PMCID: PMC7115792 DOI: 10.1016/j.vetpar.2013.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 03/01/2013] [Accepted: 03/04/2013] [Indexed: 12/05/2022]
Abstract
Two field studies were accomplished on a dairy farm in Saxony to compare different strategies for the control of natural cryptosporidiosis in newborn calves. In the first study, 96 newborn calves were allocated to four different groups immediately after birth. Calves of group H and of group HN were treated orally with 120 μg/kg body weight (BW) of halofuginone lactate daily during the first seven days of life. Calves of group C and of group CN were treated with a same volume of tap water. As an additional measure, the pens of groups HN and CN were disinfected with 3% Neopredisan 135-1®(p-chloro-m-cresol), the pens of groups C and H remained non-disinfected. Faeces were examined semi-quantitatively for oocyst excretion using carbolfuchsin-staining and the clinical course was recorded. While disinfection alone (group CN) had no effect on oocyst shedding and diarrhoea, treatment with halofuginone lactate (groups H and HN) reduced oocyst shedding and diarrhoea significantly. Combination of treatment and disinfection (group HN) controlled cryptosporidiosis completely during the first two weeks after birth. However, prevalence of diarrhoea and oocyst shedding was higher in the third week of life in group HN than in any of the other groups. This delayed occurrence of cryptosporidiosis was not seen in study 2 when all calves were similarly protected by treatment and specific disinfection. Oocyst shedding was not observed in peripartal cows either by carbolfuchsin staining, ELISA or PCR.
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Affiliation(s)
- Judith Keidel
- (ko)VET, Coordination Staff for Veterinary Clinical Studies, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 33, D-04103 Leipzig, Germany.
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Němejc K, Sak B, Květoňová D, Kernerová N, Rost M, Cama VA, Kváč M. Occurrence of Cryptosporidium suis and Cryptosporidium scrofarum on commercial swine farms in the Czech Republic and its associations with age and husbandry practices. Parasitol Res 2013; 112:1143-54. [PMID: 23271566 PMCID: PMC4724874 DOI: 10.1007/s00436-012-3244-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 12/10/2012] [Indexed: 11/30/2022]
Abstract
From 2009 to 2011, the occurrence of Cryptosporidium spp. was investigated on 22 farms in the Czech Republic. A total of 1,620 individual faecal samples of pigs of all age categories (pre-weaned, starters, pre-growers, growers, and sows) were evaluated for presence of Cryptosporidium spp. by standard microscopy and molecular tools. Genotyping was done through PCR amplification and characterization of the SSU rRNA (species-specific protocols) and GP60 loci. Cryptosporidium spp. was found on 16 of 22 farms with a range 0.9-71.4 %. Overall, 194 (12 %) specimens were positive by microscopy and 353 (21.8 %) by PCR. While RFLP and direct sequencing of the PCR-amplified products showed presence of Cryptosporidium suis (142), Cryptosporidium scrofarum (195), Cryptosporidium muris (3) and 13 samples had mixed infections with C. suis and C. scrofarum, species-specific molecular tools identified C. suis (224), C. scrofarum (208), Cryptosporidium parvum subtype IIa A16G1R1b (1), and C. muris (3). In addition, a total of 82 pigs had concurrent infections with C. suis and C. scrofarum. The analysis by age showed that C. suis was primarily detected among pre-weaned, whereas C. scrofarum was mostly detected among starters, especially those weaned at a younger age. Moreover, C. scrofarum never has been detected in animals younger than 6 weeks of age. Also, piglets weaned at 3 weeks of age were twice more likely to be infected with C. scrofarum than piglets weaned at an older age. Pigs raised on straw bedding were more likely to have Cryptosporidium than pigs raised on slats/slurry systems. The infections with different species were not associated with loose faeces or intensity of oocyst shedding, even when comparing different age groups.
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Affiliation(s)
- Karel Němejc
- Faculty of Agriculture, University of South Bohemia in České Budějovice, Studentská 13, 370 05, České Budějovice, Czech Republic
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15
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Individual subject meta-analysis of parameters for Cryptosporidium parvum shedding and diarrhoea in animal experimental models. Epidemiol Infect 2012; 141:1662-78. [PMID: 23068915 DOI: 10.1017/s0950268812002294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cryptosporidium is a zoonotic protozoan parasite with public health importance worldwide. The objectives of this study were to (1) conduct a meta-analysis of published literature for oocyst shedding and diarrhoea outcomes, and (2) develop recommendations for standardization of experimental dose-response studies. Results showed that for the outcome of oocyst shedding in faeces, the covariates 'experimental species', 'immunosuppression', 'oocyst dose' and 'oocyst dose' × 'age' were all significant (P≤0.05). This study suggests that exposing mice, piglets, or ruminants, and using immunosuppressed experimental hosts, is more likely to result in oocyst shedding. For the outcome of diarrhoea in experimentally infected animal species, the key covariates 'experimental species', 'age' and 'immunosuppression' were significant (P≤0.2). Therefore, based on the results of this meta-analysis, these variables should be carefully reported and considered when designing experimental dose-response studies. Additionally, detection of possible publication bias highlights the need to publish additional studies that convey statistically non-significant as well as significant results in the future.
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Molecular characterization of Cryptosporidium in pigs in central Vietnam. Parasitol Res 2012; 112:187-92. [PMID: 23052759 DOI: 10.1007/s00436-012-3124-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 09/10/2012] [Indexed: 10/27/2022]
Abstract
Little information is available on the epidemiology of Cryptosporidium in pigs in central Vietnam. The aims of this study were to investigate the prevalence and to characterize the genotype distribution of Cryptosporidium isolates in pigs in this region. A total of 193 pig fecal samples were screened for the presence of Cryptosporidium oocysts using the modified Ziehl-Neelsen staining method, and 28 (overall prevalence 14.5 %) were identified as positive by microscopic observation. Positive samples were further analyzed by polymerase chain reaction amplification and sequencing. Genetic identification based on the 18S ribosomal RNA and 70 kDa heat shock protein genes revealed that pigs in Vietnam are infected with two species/genotypes (Cryptosporidium suis and Cryptosporidium pig genotype II). This study is the first molecular characterization of Cryptosporidium in pigs in Vietnam. The presence of these host-adapted species/genotypes suggests that pigs may not pose a significant public health risk in this area. More extensive studies are necessary to ascertain the zoonotic potential of Cryptosporidium in porcine hosts in Vietnam.
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Kváč M, Kestřánová M, Pinková M, Květoňová D, Kalinová J, Wagnerová P, Kotková M, Vítovec J, Ditrich O, McEvoy J, Stenger B, Sak B. Cryptosporidium scrofarum n. sp. (Apicomplexa: Cryptosporidiidae) in domestic pigs (Sus scrofa). Vet Parasitol 2012; 191:218-27. [PMID: 23021264 DOI: 10.1016/j.vetpar.2012.09.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 09/03/2012] [Accepted: 09/04/2012] [Indexed: 10/27/2022]
Abstract
We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81-5.96 μm (mean=5.16)×4.23-5.29 μm (mean=4.83) with a length to width ratio of 1.07±0.06 (n=400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4-6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250-4000 oocysts per gram of feces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB/c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species.
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Affiliation(s)
- Martin Kváč
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., České Budějovice, Czech Republic.
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Several enteropathogens are circulating in suckling and newly weaned piglets suffering from diarrhea in the province of Villa Clara, Cuba. Trop Anim Health Prod 2012; 45:435-40. [PMID: 22843242 PMCID: PMC7089418 DOI: 10.1007/s11250-012-0236-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2012] [Indexed: 11/11/2022]
Abstract
Intestinal contents of suckling (n = 45) and newly weaned (n = 45) piglets, suffering from diarrhea in the province of Villa Clara in Cuba, were tested for viral, bacterial, and parasitic enteropathogens from May to June 2008. At least one enteropathogen was identified in 53.3 % of piglets and enterotoxigenic Escherichia coli (ETEC; 25.6 %) was the major pathogen; mostly STa+/STb+ or F4+/STa+/STb+ ETEC were isolated. The overall occurrence of the rest of pathogens was 10 % for transmissible gastroenteritis virus (TGEV) and Cryptosporidium parvum, 6.7 % for rotavirus A and Isospora suis, 5.6 % for α-toxigenic Clostridium perfringens, 3.3 % for verotoxigenic E. coli (VTEC), and 2.2 % for Salmonella enterica subspecies enterica serovar Newport. TGEV and α-toxigenic C. perfringens were only identified in suckling piglets, while Salmonella Newport and VTEC were only detected in weaned pigs. Porcine epidemic diarrhea virus (PEDV), β-toxigenic C. perfringens, Eimeria spp., and helminths were not identified. Eight kinds of mixed infections were detected in 25 % of enteropathogen positive piglets. ETEC was present in 10 of 12 mixed infections, and TGEV infections were never combined. This survey demonstrates that several enteropathogens are circulating in piggeries located in the province of Villa Clara in Cuba, and that is necessary to improve surveillance, prevention, and control of enteric infections in order to increase production efficiency.
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Prevalence of Cryptosporidium spp. in pigs in Shanghai, China. Vet Parasitol 2011; 181:113-9. [DOI: 10.1016/j.vetpar.2011.04.037] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 04/11/2011] [Accepted: 04/21/2011] [Indexed: 11/24/2022]
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20
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Lippke RT, Borowski SM, Marques SM, Paesi SO, Almeida LL, Moreno AM, Corbellini LG, Barcellos DED. Matched case-control study evaluating the frequency of the main agents associated with neonatal diarrhea in piglets. PESQUISA VETERINARIA BRASILEIRA 2011. [DOI: 10.1590/s0100-736x2011000600008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A case-control study was carried out in litters of 1 to 7-day-old piglets to identify the main infectious agents involved with neonatal diarrhea in pigs. Fecal samples (n=276) from piglets were collected on pig farms in the State of Rio Grande do Sul, Brazil, from May to September 2007. Litters with diarrhea were considered cases (n=129) and normal litters (n=147) controls. The samples were examined by latex agglutination test, PAGE, conventional isolating techniques, ELISA, PCR, and microscopic methods in order to detect rotavirus, bacterial pathogens (Escherichia coli, Clostridium perfringens type A and C, and Clostridium difficile), and parasites (Coccidian and Cryptosporidium spp.). Outbreaks of diarrhea were not observed during sampling. At least one agent was detected in fecal samples on 25 out of 28 farms (89.3%) and in 16 farms (57.1%) more than one agent was found. The main agents diagnosed were Coccidia (42.86%) and rotavirus (39.29%). The main agents identified in litters with diarrhea were Clostridium difficile (10.6%), Clostridium perfringens type A (8.8%) and rotavirus (7.5%); in control litters, Clostridium difficile (16.6%) and Coccidian (8.5%). Beta hemolytic Escherichia coli and Clostridium perfringens type C were not detected. When compared with controls, no agent was significantly associated with diarrhea in case litters. These findings stress the need for caution in the interpretation of laboratorial diagnosis of mild diarrhea in neonatal pigs, as the sole detection of an agent does not necessarily indicate that it is the cause of the problem.
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Prevalence and molecular identification of Cryptosporidium spp. in pigs in Henan, China. Parasitol Res 2010; 107:1489-94. [DOI: 10.1007/s00436-010-2024-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Accepted: 07/29/2010] [Indexed: 11/25/2022]
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Featherstone CA, Marshall JA, Giles M, Sayers AR, Pritchard GC. Cryptosporidium species infection in pigs in East Anglia. Vet Rec 2010; 166:51-2. [PMID: 20064979 DOI: 10.1136/vr.b4771] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- C A Featherstone
- Veterinary Laboratories Agency-Thirsk, West House, Station Road, Thirsk, North Yorkshire.
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Fayer R. Taxonomy and species delimitation in Cryptosporidium. Exp Parasitol 2009; 124:90-7. [PMID: 19303009 DOI: 10.1016/j.exppara.2009.03.005] [Citation(s) in RCA: 239] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Revised: 02/20/2009] [Accepted: 03/06/2009] [Indexed: 11/29/2022]
Abstract
Amphibians, reptiles, birds and mammals serve as hosts for 19 species of Cryptosporidium. All 19 species have been confirmed by morphological, biological, and molecular data. Fish serve as hosts for three additional species, all of which lack supporting molecular data. In addition to the named species, gene sequence data from more than 40 isolates from various vertebrate hosts are reported in the scientific literature or are listed in GenBank. These isolates lack taxonomic status and are referred to as genotypes based on the host of origin. Undoubtedly, some will eventually be recognized as species. For them to receive taxonomic status sufficient morphological, biological, and molecular data are required and names must comply with the rules of the International Code for Zoological Nomenclature (ICZN). Because the ICZN rules may be interpreted differently by persons proposing names, original names might be improperly assigned, original literature might be overlooked, or new scientific methods might be applicable to determining taxonomic status, the names of species and higher taxa are not immutable. The rapidly evolving taxonomic status of Cryptosporidium sp. reflects these considerations.
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Affiliation(s)
- Ronald Fayer
- Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA.
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Prevalence and age-related infection of Cryptosporidium suis, C. muris and Cryptosporidium pig genotype II in pigs on a farm complex in the Czech Republic. Vet Parasitol 2009; 160:319-22. [DOI: 10.1016/j.vetpar.2008.11.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 11/03/2008] [Accepted: 11/05/2008] [Indexed: 11/18/2022]
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Prevalence of Cryptosporidium genotypes in pre and post-weaned pigs in Australia. Exp Parasitol 2008; 119:418-21. [DOI: 10.1016/j.exppara.2008.04.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Revised: 04/07/2008] [Accepted: 04/08/2008] [Indexed: 11/17/2022]
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Chen F, Huang K. Prevalence and Phylogenetic Analysis of Cryptosporidium in Pigs in Eastern China. Zoonoses Public Health 2007; 54:393-400. [DOI: 10.1111/j.1863-2378.2007.01078.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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27
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Suárez-Luengas L, Clavel A, Quílez J, Goñi-Cepero MP, Torres E, Sánchez-Acedo C, del Cacho E. Molecular characterization of Cryptosporidium isolates from pigs in Zaragoza (northeastern Spain). Vet Parasitol 2007; 148:231-5. [PMID: 17683866 DOI: 10.1016/j.vetpar.2007.06.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Revised: 06/12/2007] [Accepted: 06/18/2007] [Indexed: 11/19/2022]
Abstract
A total of 142 stool specimens from pigs on 24 farms from the province of Zaragoza (northeastern Spain) were screened for Cryptosporidium spp. Samples were first analysed by routine techniques (formalin-ethyl acetate sedimentation method and modified Ziehl-Neelsen stain) selecting those microscopically positive for genetic characterization. Cryptosporidium species and genotypes were determined by a nested PCR-RFLP technique at the 18S ribosomal DNA locus and sequencing of the PCR-positive secondary products. Cryptosporidium oocysts were microscopically identified in the faeces of 32 pigs (22.5%) from 15 farms (62.5%). Infected animals included 23 weaned piglets (30.7%), 5 fattening pigs (11.9%) and 4 sows (16%). Diarrhoea was not detected in any of the infected pigs. The molecular characterization was successfully performed in 26 samples from 14 farms. Cryptosporidium suis was found in 10 specimens from 7 farms (nine weaned piglets and one sow) and the Cryptosporidium pig genotype II in 16 samples from 10 farms (13 weaned piglets and 3 fattening pigs). Both C. suis and the pig genotype II were concurrently detected on three farms.
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Affiliation(s)
- Laura Suárez-Luengas
- Department of Microbiology, Preventive Medicine and Public Health, Faculty of Medicine, University of Zaragoza, Domingo Miral s/n, 50009 Zaragoza, Spain
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Hamnes IS, Gjerde BK, Forberg T, Robertson LJ. Occurrence of Cryptosporidium and Giardia in suckling piglets in Norway. Vet Parasitol 2006; 144:222-33. [PMID: 17123737 DOI: 10.1016/j.vetpar.2006.10.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Revised: 10/10/2006] [Accepted: 10/17/2006] [Indexed: 11/20/2022]
Abstract
Faecal samples from 684 litters of suckling piglets from 100 indoor swine herds from all regions of Norway were examined for the presence of Cryptosporidium and Giardia, using sucrose gradient flotation concentration and immunofluorescent staining. Thirty-one (31%) herds and 57 (8.3%) litters tested positive for Cryptosporidium, while 10 (1.5%) litters in 10 different herds (10%) tested positive for Giardia. Molecular characterisation of nine Cryptosporidium isolates demonstrated both C. suis and Cryptosporidium sp. pig genotype II. There was significantly more diarrhoea among the Cryptosporidium positive piglets than among the Cryptosporidium negative piglets. Diarrhoea was not observed amongst litters in which Cryptosporidium sp. pig genotype II was found. There was a significant difference in the Cryptosporidium prevalence between litters from different geographical areas of Norway. This study demonstrates that both Cryptosporidium (C. suis and Cryptosporidium sp. pig genotype II) and Giardia infections are prevalent among suckling piglets in Norway.
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Affiliation(s)
- Inger Sofie Hamnes
- Norwegian School of Veterinary Science, Department of Food Safety and Infection Biology, Section of Microbiology, Immunology and Parasitology, P.O. Box 8146 Dep, N-0033 Oslo, Norway.
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Xiao L, Moore JE, Ukoh U, Gatei W, Lowery CJ, Murphy TM, Dooley JSG, Millar BC, Rooney PJ, Rao JR. Prevalence and identity of Cryptosporidium spp. in pig slurry. Appl Environ Microbiol 2006; 72:4461-3. [PMID: 16751569 PMCID: PMC1489634 DOI: 10.1128/aem.00370-06] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cryptosporidium spp. were detected in 25 of 56 pig slurry samples from 33 Irish farms by PCR and DNA sequencing. The organisms detected included C. suis, Cryptosporidium pig genotype II, and C. muris. We concluded that Cryptosporidium oocysts can persist in treated slurry and potentially contaminate surface water through improper discharge or uncontrolled runoff.
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Affiliation(s)
- Lihua Xiao
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Mail Stop F12, 4770 Buford Highway, Atlanta, GA 30341, USA.
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Slapeta J. Cryptosporidium species found in cattle: a proposal for a new species. Trends Parasitol 2006; 22:469-74. [PMID: 16920029 DOI: 10.1016/j.pt.2006.08.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 07/14/2006] [Accepted: 08/04/2006] [Indexed: 10/24/2022]
Abstract
Humans and animals are infected worldwide by apicomplexan parasites of the genus Cryptosporidium. Yet, parasitologists are continuously surprised by the expanding complexity of this genus. Over the past 20 years, cattle were identified as being a reservoir host for taxa transmitted from animals to humans. However, a remarkable assemblage of species affects cattle, including both cattle-specific, in addition to a zoonotic, species. To clarify species classification, Cryptosporidium pestis n. sp. is proposed for the species formerly recognized as the "bovine genotype" of C. parvum. The observed increasing complexity of Cryptosporidium species, along with recent advances in knowledge, should be reconsidered in the context of past records, and not vice versa. In this way, the gaps in our understanding of Cryptosporidium species can be identified and addressed in a scientific manner.
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Affiliation(s)
- Jan Slapeta
- Institute for the Biotechnology of Infectious Diseases, University of Technology-Sydney, PO Box 123, Broadway, New South Wales 2007, Australia.
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Geurden T, Goma FY, Siwila J, Phiri IGK, Mwanza AM, Gabriel S, Claerebout E, Vercruysse J. Prevalence and genotyping of Cryptosporidium in three cattle husbandry systems in Zambia. Vet Parasitol 2006; 138:217-22. [PMID: 16546321 DOI: 10.1016/j.vetpar.2006.02.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2005] [Revised: 02/02/2006] [Accepted: 02/14/2006] [Indexed: 11/28/2022]
Abstract
To estimate the prevalence of Cryptosporidium spp. in three different husbandry systems in Zambia, faecal samples were collected from calves up to the age of 3 months. Faecal consistency was scored for correlation with infection. Additionally, 45 positive samples were selected for genotyping by amplification of the 70-kDa heat shock protein (HSP-70) and the 18S rRNA gene. A total of 37 dairy, 25 beef and 92 traditional husbandry farms were visited: 250 samples were collected on dairy farms, 238 on beef farms and 256 on traditional husbandry farms. All samples were analysed using a commercial copro-antigen ELISA (Techlab)(Cryptospridium test). The calf prevalence in dairy, beef and traditional husbandry systems was 42.8%, 8.0% and 6.3%, respectively. Furthermore, 75.7% of the dairy farms, 44.0% of the beef farms and 15.2% of the traditional husbandry farms had at least one positive calf at the time of visit. Subsequently, there was a significantly higher Cryptosporidium parvum prevalence on dairy farms compared to beef or traditional farms (chi(2), P<0.001). On dairy farms low faecal consistency was correlated with C. parvum infection (chi(2), P<0.05). Both C. parvum and C. bovis were identified, although in one beef calf C. suis was found.
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Affiliation(s)
- T Geurden
- Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium.
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Vítovec J, Hamadejová K, Landová L, Kvác M, Kvetonová D, Sak B. Prevalence and Pathogenicity of Cryptosporidium suis in Pre- and Post-weaned Pigs. ACTA ACUST UNITED AC 2006; 53:239-43. [PMID: 16732883 DOI: 10.1111/j.1439-0450.2006.00950.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A total of 4338 faecal samples, 135 of sows, 3368 of pre-weaned and 835 of post-weaned piglets from eight farms in South Bohemia, Czech Republic were collected and examined for Cryptosporidium infection. No sow, but 5.7% pre-weaned and 24.1% post-weaned piglets were positive for Cryptosporidium infection. No relationship was found between diarrhoea and Cryptosporidium infection in any of the different age groups (pre- and post-weaned piglets). Four piglets, which were sporadically shedding cryptosporidia in faeces, were necropsied. Neither clinical signs of diarrhoea nor macroscopical changes were found. Histologically, a moderate infection of cryptosporidia was detected in the glandular epithelium along the large intestine, with predisposition to the ansa centralis of the colon. No inflammatory response in the lamina propria was observed. Cryptosporidia were also commonly found in the glandular epithelium of submucosal lymphoglandular complexes in the colon. Cryptosporidium isolates from all farms were identified as Cryptosporidium suis using molecular markers (SSU rRNA). All of the C. suis strains obtained were larger [6.2 (6.0-6.8) x 5.5 (5.3-5.7) microm] than any isolate described so far [4.6 (4.4-4.9) x 4.2 (4.0-4.3) microm] and did not appear to be infective for neonatal BALB/c mice.
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Affiliation(s)
- J Vítovec
- Department of Anatomy and Physiology of Farm Animals, Faculty of Agriculture, University of South Bohemia, Czech Republic
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Santín M, Dixon BR, Fayert R. Genetic Characterization of Cryptosporidium Isolates From Ringed Seals (Phoca hispida) in Northern Quebec, Canada. J Parasitol 2005; 91:712-6. [PMID: 16108576 DOI: 10.1645/ge-3438rn] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
This study reports the molecular characterization of Cryptosporidium spp. isolates identified from intestinal contents of ringed seals (Phoca hispida) from Nunavik (Quebec, Canada). Cryptosporidium spp. fragments of 18S rRNA, HSP-70, and actin loci were amplified by PCR from seal intestinal contents. PCR-positive specimens were sequenced and compared with other Cryptosporidium species and genotypes reported previously. Sequence analysis showed the presence of C. muris and 2 novel genotypes in ringed seals.
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Affiliation(s)
- Mónica Santín
- Environmental Microbial Safety Laboratory, Animal and Natural Resources Institute Agricultural Research Service, United States Department of Agriculture, Building 173, BARC-East, 10300 Baltimore Avenue, Beltsville, Maryland 20705, USA
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Abstract
PURPOSE OF REVIEW Molecular tools have been developed to detect and differentiate Cryptosporidium at the species/genotype and subtype levels. These tools have been increasingly used in the characterization of the transmission of Cryptosporidium spp. This review addresses the most recent developments in molecular epidemiology of cryptosporidiosis. RECENT FINDINGS The recent development of subtyping tools has led to better understanding of the population genetics and transmission of Cryptosporidium in humans. The population structure of C. parvum and C. hominis is apparently more complicated than previously suggested, with the likely existence of both clonal and panmictic populations. Thus, the transmission of C. parvum (genotype II) in humans is shown to be different in different areas, with zoonotic transmission important in certain places and anthroponotic transmission in others. The use of molecular tools has also led to the identification of geographic and temporal differences in the transmission of C. parvum and C. hominis, and better appreciation of the public health importance of other Cryptosporidium species/genotypes and the frequency of infections with mixed genotypes or subtypes. SUMMARY Factors involved in the transmission of human cryptosporidiosis are difficult to examine using conventional methods. The use of molecular tools has been helpful in the assessment of the zoonotic potential of various Cryptosporidium spp. and sources of human infections, and has started to play a significant role in the characterization of transmission dynamic in endemic and epidemic areas.
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Affiliation(s)
- Lihua Xiao
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
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Ryan UM, Monis P, Enemark HL, Sulaiman I, Samarasinghe B, Read C, Buddle R, Robertson I, Zhou L, Thompson RCA, Xiao L. CRYPTOSPORIDIUM SUIS N. SP. (APICOMPLEXA: CRYPTOSPORIDIIDAE) IN PIGS (SUS SCROFA). J Parasitol 2004; 90:769-73. [PMID: 15357067 DOI: 10.1645/ge-202r1] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Molecular and biological characteristics of a new species of Cryptosporidium from the feces of pigs (Sus scrofa) is described. Oocysts are structurally indistinguishable from those of Cryptosporidium parvum; they are passed fully sporulated, lack sporocysts, and measure 4.9-4.4 microm (mean = 4.6 microm) x 4.0-4.3 microm (mean = 4.2 microm); length to width ratio 1.1 (n = 50). Cryptosporidium suis is not transmissible to nude mice and is poorly infectious for cattle. Molecular and phylogenetic analyses at the 18S ribosomal RNA, heat shock protein 70, and actin gene loci demonstrate C. suis to be genetically distinct from all known species and genotypes of Cryptosporidium, and thus is named as Cryptosporidium suis.
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Affiliation(s)
- U M Ryan
- Division of Health Sciences, Murdoch University, Murdoch Drive, Murdoch, Perth, WA 6150, Australia.
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Santín M, Trout JM, Xiao L, Zhou L, Greiner E, Fayer R. Prevalence and age-related variation of Cryptosporidium species and genotypes in dairy calves. Vet Parasitol 2004; 122:103-17. [PMID: 15177715 DOI: 10.1016/j.vetpar.2004.03.020] [Citation(s) in RCA: 309] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2003] [Revised: 03/28/2004] [Accepted: 03/31/2004] [Indexed: 11/27/2022]
Abstract
Fifteen dairy farms in seven states on the east coast of the US were each visited on two consecutive years to determinate the prevalence of Cryptosporidium species in pre-weaned (5 days to 2 months) and post-weaned calves (3-11 months), respectively. After each of 971 fecal specimens collected directly from each calf was sieved and subjected to density gradient centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy, and polymerase chain reaction (PCR). For all PCR-positive specimens the 18S rRNA gene of Cryptosporidium was sequenced. Cryptosporidium was identified from all farms. Types of housing appeared to have no influence with regard to prevalence of infection. Of 971 calves, 345 were infected with Cryptosporidium (35.5%), but more pre-weaned calves (253 of 503; 50.3%) than post-weaned calves (92 of 468; 19.7%) were found to be infected. A total of 278 PCR-positive specimens characterized by gene sequencing revealed Cryptosporidium parvum, Cryptosporidium andersoni, and two unnamed Cryptosporidium genotypes Bovine B (AY120911) and deer-like genotype (AY120910). The prevalence of these Cryptosporidium species and genotypes appeared to be age related between pre- and post-weaned calves. C. parvum, the only zoonotic species/genotype, constituted 85% of the Cryptosporidium infections in pre-weaned calves but only 1% of the Cryptosporidium infections in post-weaned calves. These findings clearly demonstrate that earlier reports on the presence and prevalence of C. parvum in post-weaned cattle that were based solely on oocyst morphology must be reassessed using molecular methods to validate species and genotype. This finding also indicates that persons handling or otherwise exposed to calves under 2 months of age are at greater risk of zoonotic infection from Cryptosporidium than the risk of infection from exposure to older calves.
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Affiliation(s)
- Mónica Santín
- Environmental Microbial Safety Laboratory, Animal and Natural Resources Institute, Agricultural Research Service, United States Department of Agriculture, Building 173, BARC-East, 10300 Baltimore Avenue, Beltsville, MD 20705, USA
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Xiao L, Fayer R, Ryan U, Upton SJ. Cryptosporidium taxonomy: recent advances and implications for public health. Clin Microbiol Rev 2004; 17:72-97. [PMID: 14726456 PMCID: PMC321466 DOI: 10.1128/cmr.17.1.72-97.2004] [Citation(s) in RCA: 544] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There has been an explosion of descriptions of new species of Cryptosporidium during the last two decades. This has been accompanied by confusion regarding the criteria for species designation, largely because of the lack of distinct morphologic differences and strict host specificity among Cryptosporidium spp. A review of the biologic species concept, the International Code of Zoological Nomenclature (ICZN), and current practices for Cryptosporidium species designation calls for the establishment of guidelines for naming Cryptosporidium species. All reports of new Cryptosporidium species should include at least four basic components: oocyst morphology, natural host specificity, genetic characterizations, and compliance with the ICZN. Altogether, 13 Cryptosporidium spp. are currently recognized: C. muris, C. andersoni, C. parvum, C. hominis, C. wrairi, C. felis, and C. cannis in mammals; C. baïleyi, C. meleagridis, and C. galli in birds; C. serpentis and C. saurophilum in reptiles; and C. molnari in fish. With the establishment of a framework for naming Cryptosporidium species and the availability of new taxonomic tools, there should be less confusion associated with the taxonomy of the genus Cryptosporidium. The clarification of Cryptosporidium taxonomy is also useful for understanding the biology of Cryptosporidium spp., assessing the public health significance of Cryptosporidium spp. in animals and the environment, characterizing transmission dynamics, and tracking infection and contamination sources.
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Affiliation(s)
- Lihua Xiao
- Division of Parasitic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Chamblee, Georgia 30341, USA.
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