Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-24T06:28:19.197Z Has data issue: false hasContentIssue false

Cryptosporidium and its potential as a food-borne pathogen

Published online by Cambridge University Press:  28 February 2007

Geraldine Duffy*
Affiliation:
The National Food Centre, Teagasc, Ashtown, Dublin 15, Ireland
Elaine M. Moriarty
Affiliation:
The National Food Centre, Teagasc, Ashtown, Dublin 15, Ireland
*

Abstract

Cryptosporidium species are intestinal protozoan parasites and are excreted in animal feces as stable oocysts. Cryptosporidium has now been detected in the feces of a wide range of ruminant and non-ruminant farmed animals, wild animals, domestic pets and birds and the parasite appears to be well adapted to survive and persist in feces for extended periods, ranging from several weeks to many months. Because of this persistence, these materials are important as potential vehicles of transmission within herds, farms, the water chain, the fresh food chain, and the wider environment. Appropriate handling of animal waste is necessary to control spread of this pathogen and to limit the significant risks of human infection. While water is a well-recognized vector of Cryptosporidium, it has only recently emerged that food may play a more significant role than previously realized in the transmission of the Cryptosporidium to humans. In the last 3–5 years, research efforts have been directed both at the development of suitable methods for isolation and detection of the parasite in foods and at the application of these methods to assess the prevalence and persistence of the parasite in a range of foods. Additionally, molecular subtyping methods have been used to establish the transmission routes of the parasite. This paper summarizes the general biology of Cryptosporidium and overviews the current research on C. parvum in the food chain. The risks posed by certain foods, such as salad/vegetable crops and beef, are discussed and control measures which may be useful in the farm-to-fork chain for these products are described.

Type
Review Article
Copyright
Copyright © CAB International 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Angus, KW, Tzipori, S and Gray, EW (1982). Intestinal lesions in specific pathogen free lambs associated with a Cryptosporidium from calves with diarrhea. Veterinary Pathology 19: 6778.CrossRefGoogle ScholarPubMed
Armon, R, Gold, D, Brodsky, M and Oron, G (2002). Surface and subsurface irrigation with effluents of different qualities and presence of Cryptosporidium oocysts in soil and crops. Water Science and Technology 46: 115120.CrossRefGoogle Scholar
Arrowood, MJ and Sterling, CR (1987). Isolation of Cryptosporidium oocysts and sporozoites using discontinuous sucrose and isopycnic gradients. Journal of Parasitology 73: 314319.CrossRefGoogle Scholar
Baeumner, AJ, Humiston, MC, Montagna, RA and Durst, RA (2001). Detection of viable oocysts of Cryptosporidium parvum following nucleic acid sequence based amplification. Analytical Chemistry 73: 11761180.CrossRefGoogle ScholarPubMed
Barrick, RS, Mohammed, HQ, White, ME and Bryant, RB (2003). Factors associated with the likelihood of Giardia and Cryptosporidium spp. in soil from dairy farms. Journal of Dairy Science 86: 784791.CrossRefGoogle Scholar
Bayer, MR and Wright, AE (1990). Cryptosporidium and water. Letters in Applied Microbiology 11: 272277.Google Scholar
Bier, JW (1991). Isolation of parasites on fruits and vegetables. Southeast Asian Journal of Tropical Medicine in Public Health 22 (Suppl.): 144145.Google ScholarPubMed
Bonnin, A, Fourmaux, MN, Dubremetz, JF, Nelson, RG, Gobet, P, Harly, G, Buisson, M, Puygauthier-Toubas, D, Gabriel-Pospisil, F, Naciri, M and Camerlynck, P (1996). Genotyping human and bovine isolates of Cryptosporidium parvum by polymerase chain reaction-restriction fragment length polymorphism analysis of a repetitive DNA sequence. Microbiology Letters 137: 207211.CrossRefGoogle ScholarPubMed
Bujoczek, G, Reiners, RS and Olaszkiewicz, JA (2001). Abiotic factors affecting inactivation of pathogens in sludge. Water Science and Technology 44: 10, 7984.CrossRefGoogle ScholarPubMed
Bukhari, Z, Marshall, MM, Korich, DG, Fricker, CR, Smith, HV, Rosen, J and Clancy, JL (2000). Comparison of Cryptosporidium parvum viability and infectivity assays following ozone treatment of oocysts. Applied and Environmental Microbiology 66: 29722980.CrossRefGoogle ScholarPubMed
Cacciù, S, Homan, H, Camilli, R, Traldi, G, Kortbeek, T and Pozio, E (2000). A microsatellite marker reveals population heterogeneity within human and animal genotypes of Cryptosporidium parvum. Parasitology 120: 237244.CrossRefGoogle Scholar
Cacciù, S, Spano, F and Pozio, E (2001). Large sequence variation at two microsatellite loci among zoonotic (genotype C) isolates of Cryptosporidium parvum. International Journal for Parasitology 31: 10821086.CrossRefGoogle Scholar
Cai, J, Collins, MD, McDonald, V and Thompson, DE (1992). PCR cloning and nucleotide sequence determination of the 18S rRNA genes and internal transcriber spacer 1 of the protozoan parasites Cryptosporidium parvum and Cryptosporidium muris. Biochimica et Biophysica Acta 1131: 317320.CrossRefGoogle ScholarPubMed
Campbell, I, Tzipori, S, Hutchinson, G and Angus, KW (1982). Effects of disinfectants on survival of Cryptosporidium oocysts. Veterinary Record 111: 414415.CrossRefGoogle ScholarPubMed
Casemore, DP (1989). Sheep as a source of human cryptosporidiosis. Journal of Infection 19: 101104.CrossRefGoogle ScholarPubMed
Casemore, DP (1991). Laboratory methods for diagnosing cryptosporidiosis. Clinical Pathology 44: 445451.CrossRefGoogle ScholarPubMed
Casemore, DP, Jessop, EG, Douce, D and Jackson, FB (1986). Cryptosporidium plus Campylobacter: an outbreak in a semi-rural population. Journal of Hygiene (London) 96: 95105.CrossRefGoogle Scholar
Cassin, MH, Lammerding, AM, Todd, EC, Ross, W and McColl, RS (1998). Quantitative risk assessment for Escherichia coli in ground beef hamburgers. International Journal of Food Microbiology 41: 2144.CrossRefGoogle ScholarPubMed
CDC (Center for Disease Control) (1982). Cryptosporidiosis: assessment of males with acquired immune deficiency syndrome (AIDS). Morbidity and Mortality Weekly Report 31: 589592.Google Scholar
CDC (Center for Disease Control Prevention) (1996). Foodborne outbreak of diarrheal illness associated with Cryptosporidium parvum Minnesota 1995. Morbidity and Mortality Weekly Report 45: 783784.Google Scholar
CDC (Center for Disease Control Prevention) (1997). Foodborne outbreak of cryptosporidiosis Spokane Washington, 1997. Morbidity and Mortality Weekly Report 73: 353355.Google Scholar
Cook, N (2003). The use of NASBA for the detection of microbial pathogens in food and environmental samples. Journal of Microbiological Methods 53: 165174.CrossRefGoogle ScholarPubMed
Current, WL, Upton, SJ and Hanes, TB (1986). The life cycle of Cryptosporidium baileyi n. sp. (Apicomplexa: Cryptosporidiidae) infecting chickens. Journal of Protozoology 33: 289.CrossRefGoogle Scholar
Current, WL and Garcia, LS (1991). Cryptosporidiosis. Clinical Microbiology Reviews 4: 325358.CrossRefGoogle ScholarPubMed
Current, WL and Reese, NC (1986). A comparison of endogenous development of three isolates of Cryptosporidium in suckling mice. Journal of Protozoology 33: 98108.CrossRefGoogle ScholarPubMed
D·Antonio, RG, Winn, RE, Taylor, JP, Gustafson, TL, Current, WL, Rhodes, MM, Gray, GW and Zadac, RA (1985). A waterborne outbreak of cryptosporidiosis in normal hosts. Annals of Internal Medicine 103: 886888.CrossRefGoogle ScholarPubMed
Deng, MQ and Cliver, DO (1999). Cryptosporidium parvum studies with dairy products. International Journal of Food Microbiology 46: 113121.CrossRefGoogle ScholarPubMed
Deng, MQ and Cliver, DO (2000). Comparative detection of Cryptosporidium parvum oocysts from apple juice. International Journal of Food Microbiology 54: 155162.CrossRefGoogle ScholarPubMed
Duffy, G, McEvoy, JM, Moriarty, EM and Sheridan, JJ (2003) A study of Cryptosporidium parvum in beef. Teagasc Project Report RMIS 4723. Dublin: Teagasc, National Food Centre.Google Scholar
Dworkin, MS, Goldman, DP, Wells, TG, Kobayashi, JM and Herwaldt, BL (1996). Cryptosporidiosis in Washington State: an outbreak associated with well water. Journal of Infectious Diseases 174: 13721376.CrossRefGoogle ScholarPubMed
Elsser, KA, Moricz, M and Proctor, EM (1986). Cryptosporidium infections: a laboratory survey. Canadian Medical Association Journal 135: 211213.Google ScholarPubMed
Enemark, HL, Ahrens, P, Lowery, CJ, Thamsborg, SM, Enemark, JMD, Billie-Hansen, V and Lind, P (2002). Cryptosporidium andersoni from a Danish cattle herd: identification and preliminary characterization. Veterinary Parasitology 107: 3749.CrossRefGoogle Scholar
Enemark, HL, Juel, CD and Cacciù, S (2003) Effects of environmental conditions on Cryptosporidium oocysts viability. In: Duffy, G (editor). Conference proceedings, Cryptosporidium parvum in Food and Water held at Grand Hotel Malahide, Dublin January 29th 20003. Dublin: Teagasc, National Food Centre, pp.3647.Google Scholar
Ernest, JA, Blagburn, BL, Lindsay, DS and Current, WL (1986). Infection dynamics of Cryptosporidium parvum (Apicomplexa: Cryptosporidiidae) in neonatal mice (Mus musculus). Journal of Parasitology 72: 796798.CrossRefGoogle ScholarPubMed
Ernst, JV, Steward, TB and Witlock, DR (1987). Quantitative determinations of coccidia oocysts in beef calves from coastal plain area of Georgia (USA). Veterinary Parasitology 23: 110.CrossRefGoogle Scholar
Eurosurveillance Weekly (2003) Cryptosporidium parvum, 7 outbreak in swimming pool in Alcudia, Majorca Spain. Eurosurveillance Weekly (33). www.eurosurveillance. org/ew/2003.Google Scholar
Fayer, R (editor) (1997) Cryptosporidium and cryptosporidiosis. NewYork: CRC Press.Google Scholar
Fayer, R and Ungar, LP (1986). Cryptosporidium spp. and cryptosporidiosis. Microbiological Reviews 50: 458483.CrossRefGoogle ScholarPubMed
Fayer, R, Trout, JM, Graczyk, TK and Lewis, EJ (2000). Prevalence of Cryptosporidium, Giardia and Eimeria infections in post-weaned and adult cattle on three Maryland farms. Veterinary Parasitology 93: 103112.CrossRefGoogle ScholarPubMed
Fayer, R, Morgan, U and Upton, SJ (2000). Epidemiology of Cryptosporidium: transmission, detection and identification. International Journal of Parasitology 30: 3051322.CrossRefGoogle ScholarPubMed
Fayer, R, Trout, JM, Lewis, EJ, Xiao, L, Lal, A, Jenkins, MC and Graczyk, TK (2002). Temporal variability of Cryptosporidium in the Chesapeake Bay. Parasitology Research 88: 9981003.Google ScholarPubMed
Fayer, R, Trout, JM, Lewis, EJ, Santin, M, Zhou, L, Lal, AA and Xiao, L (2003). Contamination of Atlantic coast commercial shellfish with Cryptosporidium. Parasitology Research 89: 141145.Google ScholarPubMed
Filkorn, R, Wiedenmann, A and Botzenhart, K (1994). Selective detection of viable Cryptosporidium oocysts by PCR. Zentralblatt für Hygiene und Umweltmedizin 195: 489494.Google ScholarPubMed
Finch, GR, Daniels, CW, Black, EK, Schaefer, FW III and Belosevic, M (1993). Dose response of Cryptosporidium parvum in outbred neonatal CD-1 mice. Applied and Environmental Microbiology 59: 36613665.CrossRefGoogle ScholarPubMed
Fournier, S, Dubrou, S, Liguory, O, Gaussin, F, Santillana-Hayat, M, Sarfati, C, Molian, J M and Derouin, F (2002). Detection of microsporidia, Cryptosporidium and Giardia in swimming pools: a one year prospective study. FEMS Microbiology Letters 33: 209213.Google ScholarPubMed
Friedman, DE, Patten, KA, Ose, JB and Barney, MC (1997). The potential for Cryptosporidium parvum oocyst survival in beverages associated with contaminated tap water. Journal of Food Safety 17: 125132.CrossRefGoogle Scholar
Fujino, T, Matsui, T, Kobay Ash, F, Haruki, K, Yoshino, Y, Kajima, J and Tsui, M (2002). The effect of heating against Cryptosporidium oocysts. Journal of Veterinary Medical Science 64: 199200.CrossRefGoogle ScholarPubMed
Gatti, S, Cevini, C, Bruno, A, Bernuzzi, AM and Scaglia, M (1993). Cryptosporidiosis in tourists returning from Egypt and the island of Mauritius. Clinical Infectious Diseases 16: 344345.CrossRefGoogle ScholarPubMed
Gelletlie, R, Stuart, J, Soltanpoor, N, Armstrong, R and Nichols, G (1997). Cryptosporidiosis associated with school milk. Lancet 350: 10051006.CrossRefGoogle ScholarPubMed
Gold, D and Stein, BTzipori, S (2001). The utilization of sodium taurocholate in excystation of Cryptosporidium parvum and infection of tissue culture. Journal of Parasitology 87: 9971000.CrossRefGoogle ScholarPubMed
Gomez-Bautista, M, Ortega-Mora, LM, Tabares, E, Lopez-Rodas, V and Costas, E (2000). Detection of infectious Cryptosporidium parvum oocysts in mussels (Mytilus galloprovincialis) and cockles (Cerastoderma edule). Applied and Environmental Microbiology 66: 1866–70.CrossRefGoogle ScholarPubMed
Gùmez-Couso, H, Freire-Santos, F, Martinez-Urtaza, J, Garcia-Martin, O and Ares-Mazas, ME (2003). Contamination of bivalve molluscs by Cryptosporidium oocysts: the need for new quality control standards. International Journal of Food Microbiology 87: 97105.CrossRefGoogle Scholar
Hallier-Soulier, S and Guillot, E (2003). An immunomagnetic separation-reverse transcription polymerase chain reaction (IMS-RT-PCR) test for sensitive and rapid detection of viable waterborne Cryptosporidium parvum. Environmental Microbiology 5: 592598.CrossRefGoogle ScholarPubMed
Harp, JA, Fayer, R, Pesch, BA and Jackson, GJ (1996). Effect of pasteurization on infectivity of Cryptosporidium parvum oocysts in water and milk. Applied and Environmental Microbiology 62: 28662868.CrossRefGoogle ScholarPubMed
Harper, CM, Cowell, NA, Adams, BC, Langley, AJ and Wohlsem, TD (2002). Outbreak of Cryptosporidium linked to drinking unpasteurised milk. Communicable Diseases Intelligence 26: 449450.Google ScholarPubMed
Hayes, EB, Matte, TD, O'Brien, TR, McKinley, TW, Logsdon, GS, Rose, JB, Ungar, BLP, Word, DM, Pinsky, PF, Cummings, ML, Wilson, MA, Long, EG, Hurwitz, ES and Juranek, DD (1989). Large community outbreak of cryptosporidiosis due to contamination of a filtered water supply. New England Journal of Medicine 320: 13721376.CrossRefGoogle Scholar
Hoar, BR, Atwill, ER, Elmi, C and Farver, TB (2001). An examination of risk factors associated with beef cattle shedding pathogens of potential zoonotic. Epidemiology and Infection 127: 147155.CrossRefGoogle ScholarPubMed
Hoover, DM, Hoerr, FJ, Carlton, WW, Hinsman, EJ and Ferguson, HW (1981). Enteric cryptosporidiosis in a naso tang, Naso lituratus. Journal of Fish Diseases 4: 25.CrossRefGoogle Scholar
Iseki, M (1979). Cryptosporidium felis sp. n. (Protozoa: Eimeriorina) from the domestic cat. Japanese Journal of Parasitology 28: 285.Google Scholar
Jenkins, MB, Bowman, DD and Ghiorse, WC (1998). Inactivation of Cryptosporidium oocysts by ammonia. Applied and Environmental Microbiology 64: 784788.CrossRefGoogle ScholarPubMed
Kato, S, Jenkins, MB, Fogarty, EA and Bowman, DD (2002). Effects of freeze-thaw events on the viability of Cryptosporidium parvum oocysts in soil. Journal of Parasitology 88: 718722.Google ScholarPubMed
Kramer, MH, Sorhage, FE, Goldstein, ST, Dalley, E, Wahlquist, SP and Herwaldt, BL (1997). First reported outbreak in the United States of cryptosporidiosis associated with a recreational lake. Clinical Infectious Diseases 26: 2733.CrossRefGoogle Scholar
Laberge, I and Griffiths, MW (1996). Prevalence, detection and control of Cryptosporidium parvum in food. International Journal of Food Microbiology 31: 126.CrossRefGoogle Scholar
Levine, ND (1980). Some corrections of coccidian (Apicomplexa: Protozoa) nomenclature. Journal of Parasitology 66: 830.CrossRefGoogle ScholarPubMed
Levine, ND (1986). The taxonomy of Sarcocystis (Protozoa, Apicomplexa) species. Journal of Parasitology 72: 372382.CrossRefGoogle ScholarPubMed
Lindergard, G, Nydam, DV, Wade, SE, Schaaf, SL andMohammed, HO (2003). A novel multiplex polymerase chain reaction approach for detection of four human infective Cryptosporidium isolates: Cryptosporidium parvum , types H and C, Cryptosporidium canis, and Cryptosporidium felis in fecal and soil samples. Journal of Veterinary Diagnostic Investigation 15: 262277.CrossRefGoogle Scholar
Lindquist, HD, Bennett, JW, Ware, M, Stetler, RE, Gauci, M and Schaefer, FW (2001). Testing methods for detection of Cryptosporidium spp. in water samples. Southeast Asian Journal of Tropical Medicine and Public Health 32: Suppl 2190194.Google ScholarPubMed
Lindsay, DS and Blagburn, BL (1991). Cryptosporidium parvum infection of swine. Compendium 13: 891895.Google Scholar
Lindsay, DS, Upton, SJ, Owens, DS, Morgan, UM, Mead, JR and Blagburn, BL (2000). Cryptosporidium andersoni n. sp. (Apicomplexa: Cryptosporiidae) from cattle, Bos taurus. Journal of Eukaryotic Microbiology 47: 9195.CrossRefGoogle Scholar
Lopez-Velez, R, Tarazona, R, Garcia-Camacho, A, Gomez-Mampaso, E, Guerrero, A, Moreira, V and Villanueva, R (1995). Intestinal and extraintestinal cryptosporidiosis in AIDS patients. European Journal of Clinical Microbiological and Infectious Diseases 14: 677681.CrossRefGoogle ScholarPubMed
Lorenzo-Lorenzo, MJ, Ares-Mazas, E, Villacorta-Martinez, de and Maturana, I (1993). Detection of oocysts and IgG antibodies to Cryptosporidium parvum in asymptomatic adult cattle. Veterinary Parasitology 47: 915.CrossRefGoogle ScholarPubMed
Lowery, CJ, Moore, JE, Millar, BC, Burke, DP, McCorry, KAJ, Crothers, E and Dooley, JSG (2000). Detection and speciation of Cryptosporidium spp. in environmental water samples by immunomagnetic separation, PCR and endonuclease restriction. Journal of Medical icrobiology 49: 779785.Google ScholarPubMed
Lowery, CJ, Nugent, P, Moore, JE, Millar, BC, Xiru, X and Dooley, JSJ (2001). PCR-IMS detection and molecular typing of Cryptosporidium parvum recovered from a recreational river source and an associated mussel (Mytilus edulis) bed in Northern Ireland. Epidemiology and Infection 127: 545553.CrossRefGoogle Scholar
MacKenzie, WR, Hoxie, NJ, Proctor, ME, Gradus, MS, Blair, KA, Peterson, DE, Kazmierczak, DE, Addiss, DG, Fox, KR, Rose, JB and Davis, JP (1994). A massive outbreak in Milwaukee of Cryptosporidium infection transmitted through the public water supply. New England Journal of Medicine 331: 161167.CrossRefGoogle Scholar
Maillot, C, Favennec, L, Francois, A, Ducrotte, P and Brasseur, P (1997). Sexual and asexual development of Cryptosporidium parvum in five oocyst or sporozoite-infected human enterocytic cell lines. Journal of Eukaryotic Microbiology 44: 582585.CrossRefGoogle ScholarPubMed
Mann, ED, Nayar, GPS and Koschik, C (1986). Infection with Cryptosporidium spp. in humans and cattle in Manitoba. Canadian Journal of Veterinary Research 50: 174178.Google ScholarPubMed
McDonough, SP, Stull, CL and Osburn, BI (1994). Enteric pathogens in intensively reared veal calves. American Journal of Veterinary Research 55: 15161520.CrossRefGoogle ScholarPubMed
McEvoy, JM, Moriarty, EM, Duffy, G and Sheridan, JJ (2003) The role of beef in the transmission of Cryptosporidium parvum. In: Duffy, G (editor). Conference proceedings, Cryptosporidium parvum in Food and Water, Grand Hotel Malahide, Dublin January 29th 2003 Dublin: Teagasc, National Food Centre. pp. 2526.Google Scholar
Meisel, JL, Perera, DR, Meligro, C and Rubin, CE (1976). Overwhelming watery diarrhea associated with a Cryptosporidium in an immunosuppressed patient. Gastroenterology 70: 11561160.CrossRefGoogle Scholar
Meutin, DJ, Van Kruiningen, HJ and Kein, DH (1974). Cryptosporidiosis in a calf. Journal of the American Veterinary Medicine Association 165: 914914.Google Scholar
Millar, BC, Finn, M, Xiao, L, Lowery, CJ, Dooley, JS and Moore, JE (2002). Cryptosporidium in foodstuffs an emerging aetiological route of human foodborne illnesses. Trends in Food Science and Technology 13: 168187.CrossRefGoogle Scholar
Millard, PS, Gensheimer, KF, Addiss, DG, Sosin, DM, Beckett, GA, Houck-Janoski, A and Hudson, A (1994). An outbreak of cryptosporidiosis from freshly pressed apple cider. Journal of the American Medical Association 272: 15921596.CrossRefGoogle Scholar
Monge, R and Chinchilla, M (1996). Presence of Cryptosporidium oocysts in fresh vegetables. Journal of Food Protection 46: 202203.CrossRefGoogle ScholarPubMed
Moriarty, EM, McEvoy, JM, Duffy, G, Sheridan, JJ, McDowell, DA and Blair, IS (2003a) >Development of a novel method for isolating and det. Food Microbiology, in press.Development+of+a+novel+method+for+isolating+and+det.+Food+Microbiology,+in+press.>Google Scholar
Moriarty, EM, McEvoy, JM, Duffy, G, Lowery, CJ, Thompson, HP, Finn, M, Sheridan, JJ, Blair, IS and McDowell, DA (2003b) The prevalence of Cryptosporidium on beef tissue and in animal faeces at slaughter. Veterinary Record, in press.Google Scholar
Morgan-Ryan, UM, Fall, A, Ward, LA, Hijjawi, N, Sulaiman, I, Fayer, R, Thompson, RC, Olson, M, Lal, A and Xiao, L (2002). Cryptosporidium hominis n. sp. (Apicomplexa: Cryptosporidiidae) from Homo sapiens. Journal of Eukaryotic Microbiology 49: 433–40.CrossRefGoogle Scholar
MMWR (1982). Cryptosporidiosis: assessment of chemotherapy of males with acquired immune deficiency syndrome (AIDS). Morbidity and Mortality Weekly Report 31: 589592.Google Scholar
Morgan, D, Allaby, M, Crook, S, Casemore, D, Healing, TD, Soltanpoor, N, Hill, S and Hooper, W (1995). Waterborne cryptosporidiosis associated with a borehole supply. Communicable Disease Report CDR Review 5 (7): R93R97.Google ScholarPubMed
Morgan, UM, Monis, P, Xiao, L, Limor, J, Sulaiman, IM, Raidal, S, O·Donoghue, P, Gasser, R, Murray, A, Fayer, R, Blagburn, BL, Lal, AA and Thompson, RCA (2001). Molecular and phylogenetic characterisation of Cryptosporidium from birds. International Journal of Parasitology 31: 289296.CrossRefGoogle ScholarPubMed
Naciri, M, Lefay, MP and Mancassola, R (2000). Role of Cryptosporidium parvum as a pathogen in neonatal diarrhea complex in suckling and dairy calves in France. Veterinary Parasitology 85: 245257.CrossRefGoogle Scholar
Nichols, G and Thom, BT (1985). Food poisoning caused by Cryptosporidium: a load of tripe. Communicable Disease Report 85: 3.Google Scholar
Nime, FA, Burek, JD, Page, DL, Holscher, MA and Yardley, JH (1976). Acute enterocolitis in a human being infected with the protozoan Cryptosporidium. Gastroenterology 70: 592598.CrossRefGoogle Scholar
O·Donoghue, PJ (1995). Cryptosporidium and cryptosporidiosis in man and animals. International Journal for Parasitology 25: 139195.CrossRefGoogle Scholar
Orlandi, PA, Chu, DMT, Bier, JW and Jackson, GJ (2002). Parasites and the food supply. Food Technology 56: 7281.Google Scholar
Ortega, YR, Roxas, CR, Gilman, RH, Miller, NJ, Cabrera, LTaquiri, C and Sterling, CR (1997). Isolation of Cryptosporidium parvum and Cyclospora cayetanensis from vegetables collected in markets of an endemic region in Peru. American Journal of Tropical Medicine and Hygiene 57: 683686.CrossRefGoogle ScholarPubMed
Panciera, RJ, Thomassen, RW and Garner, FM (1971). Cryptosporidial infection in a calf. Veterinary Parasitology 8: 479484.Google Scholar
Peng, MM, Xiao, L, Freeman, AR, Arrowood, MJ, Escalante, AA, Weltman, AC, Ong, CSL, MacKenzie, WR, Lal, AA and Beard, CB (1997). Genetic polymorphism among Cryptosporidium parvum isolates: evidence of two distinct human transmission cycles. Emerging Infectious Diseases 3: 567573.CrossRefGoogle ScholarPubMed
Preiser, G, Preiser, L and Madeo, L (2003). An outbreak of cryptosporidiosis among veterinary science students who work with calves. Journal of American College Health 51: 213215.CrossRefGoogle ScholarPubMed
Quiroz, ES, Bern, C, MacArthur, JR, Xiao, L, Fletcher, M, Arrowood, MJ, Shay, DK, Levy, ME, Glass, RI and Lal, A (2000). An outbreak of cryptosporidiosis linked to a foodhandler. Journal of Infectious Disease 181: 695700.CrossRefGoogle ScholarPubMed
Richardson, AJ, Frankenberg, RA, Buck, AC, Selkon, JB, Colbourne, JS, Parsons, JW and Mayon-White, RT (1991). An outbreak of waterborne cryptosporidiosis in Swindon and Oxfordshire. Epidemiology and Infection 107: 485495.CrossRefGoogle ScholarPubMed
Robertson, LJ and Gjerde, B (2000). Isolation and enumeration of Giardia cysts, Cryptosporidium oocysts, and Ascaris eggs from fruit and vegetables. Journal of Food Protection 63: 775778.CrossRefGoogle Scholar
Robertson, LJ and Gjerde, B (2001a) Factors affecting recovery efficiency in isolation of Cryptosporidium oocysts and Giardia cysts from vegetables for standard method development. Journal of Food Protection 64: 17991805.CrossRefGoogle ScholarPubMed
Robertson, LJ and Gjerde, BK (2001b). Occurrence of parasites on fruits and vegetables in Norway. Journal of Food Protection 64: 17931798.CrossRefGoogle ScholarPubMed
Robertson, LJ, Campbell, AT and Smith, HV (1992). Survival of Cryptosporidium parvum oocysts under various environmental pressures. Applied and Environmental Microbiology 58: 34943500.CrossRefGoogle ScholarPubMed
Robertson, LJ, Johannessen, GS, Gjerde, BK and Loncarevic, S (2002). Microbiological analysis of seed sprouts in Norway. International Journal of Food Microbiology 75: 119126.CrossRefGoogle ScholarPubMed
Rochelle, PA, Marshall, MM, Mead, JR, Johnson, AM, Korich, DG, Rosen, JS and de Leon, R (2002). Comparison of in vitro cell culture and a mouse assay for measuring infectivity of Cryptosporidium parvum. Applied and Environmental Microbiology 68: 38093817.CrossRefGoogle Scholar
Rose, JB, Huffman, DE and Gennaccaro, A (2002). Risk and control of waterborne cryptosporidiosis. FEMS Microbiology Letters 26: 113123.CrossRefGoogle ScholarPubMed
Sayers, GM, Dillion, MC, Connolly, E, Thornton, L, Hyland, E, Loughman, E, O·Mahony, MA and Butler, KM (1996). Cryptosporidiosis in children who visited an open farm. Communicable Disease Report 6: 140144.Google ScholarPubMed
Schets, FM, van den Berg, HHJL, Verschoor, F, Engels, GB, Lodder, WJ, van Pelt-Heerschap, HML, van der Giessen, JWB, de Roda Husman, AM and van der Poel, WHM (2003) Detection of Cryptosporidium and Giardia in Portuguese oysters (Crassostrea gigas) grown in the Oosterschelde, the Netherlands. In: Duffy, G (editor). Conference proceedings, Cryptosporidium parvum in Food and Water held at Grand Hotel Malahide, Dublin January 29th 2003. Dublin: Teagasc, National Food Centre p. 21.Google Scholar
Scott, CA, Smith, HV and Gibbs, HA (1994). Excretion of Cryptosporidium parvum oocysts by a herd of beef suckler cows. Veterinary Record 134: 172.CrossRefGoogle ScholarPubMed
Scott, CA, Smith, HV, Mtambo, MMA and Gibbs, HA (1995). An epidemiological study of Cryptosporidium parvum in two herds of adult beef cattle. Veterinary Parasitology 57: 277288.CrossRefGoogle ScholarPubMed
Sharpe, AN, Hearn, EM and Kovacs-Nolan, J (2000). Comparison of membrane filtration rates and hydrophobic grid membrane filter coliform and Escherichia coli counts in food suspensions using paddle-type and pulsifier sample preparation procedures. Journal of Food Protection 63: 126130.CrossRefGoogle ScholarPubMed
Slifko, TR, Friedman, D, Rose, JB and Jakubowski, W (1997). An in vitro method for detecting infectious Cryptosporidium oocysts with cell culture. Applied and Environmental Microbiology 63: 36693675.CrossRefGoogle Scholar
Slifko, TR, Coulliette, A, Huffman, DE and Rose, JB (2000). Impact of purification procedures on the viability and infectivity of Cryptosporidium parvum oocysts. Water Science and Technology 41: 2329.CrossRefGoogle Scholar
Slavin, D (1955). Cryptosporidium meleagridis (sp. nov.). Journal of Comparative Pathology 65: 262.CrossRefGoogle ScholarPubMed
Smith, HV, Girdwood, RW, Patterson, WJ, Hardie, R, Green, LA, Benton, C, Tulloch, W, Sharp, JC and Forbes, GI (1988). Waterborne outbreak of cryptosporidiosis. Lancet 2: 86268627.Google ScholarPubMed
Spano, F, Putigani, L, McLauchlin, J, Casemore, DP and Crisanti, A (1997). PCR-RFLP analysis of the Cryptosporidium oocysts wall protein (COWP) gene discriminates between C. wrairi and C. parvum isolates of human and animal origin. Microbiology Letters 150: 209217.CrossRefGoogle Scholar
Sterling, CR, Seegar, K and Sinclair, NA (1986). Cryptosporidium as a causative agent of traveller's diarrhea. Journal of Infectious Diseases 153: 380381.CrossRefGoogle Scholar
Stinear, T, Matusan, A, Hines, K and Sandery, M (1996). Detection of a single viable Cryptosporidium parvum oocyst in environmental water concentrates by reverse transcription-PCR. Applied and Environmental Microbiology 62: 33853390.CrossRefGoogle ScholarPubMed
Svoboda, IF, Read, IA, Kemp, JS, Wright, SE, Coop, RL, Mawdsley, JL, Bargett, RD, Merry, RJ, Pain, BF, Theodorou, MK, Bukhari, Z and Smith, HV (1997). Cryptosporidium on cattle farms. In: Cryptosporidium in water: the challenge to policy makers and water managers. Symposium of the Chartered Institute of Water and Environmental Management, Glasgow, pp.320.Google Scholar
Tyzzer, EE (1910). An extracellular coccidium, Cryptosporidium muris (Gen. et. sp. nov.) of the gastric glands of the common mouse. Journal of Medical Research 23: 487.Google ScholarPubMed
Tyzzer, EE (1912). Cryptosporidium parvum (sp. nov.), a coccidium found in the small intestine of the common mouse. Archiv für Protistenkunde 26: 394412.Google Scholar
Tzipori, S, Angus, KW, Campbell, I and Clerihew, LW (1981). Diarrhea due to Cryptosporidium infection in artificially reared lambs. Journal of Clinical Microbiology 14: 100105.CrossRefGoogle ScholarPubMed
Upton, SJ, Tilley, M and Brillhart, DB (1994). Comparative development of Cryptosporidium parvum (Apicomplexa) in 11 continuous host cell lines. FEMS Microbiology Letters 118: 233236.CrossRefGoogle ScholarPubMed
Upton, SJ, Tilley, M and Brillhart, DB (1995). Effects of select medium supplements on in vitro development of Cryptosporidium parvum in HCT-8 cells. Journal of Clinical Microbiology 33: 371375.CrossRefGoogle ScholarPubMed
Vetterling, JM, Jervis, HR, Merrill, TG and Sprinz, H (1971). Cryptosporidium wrairi sp. n. from the guinea pig Cavia porcellus, with an emendation of the genus. Journal of Protozoology 18: 243247.CrossRefGoogle Scholar
Villacorta, I, Ares-Mazas, E and Lorenzo, MJ (1991). Cryptosporidium parvum in cattle, sheep and pigs in Galicia (N.W. Spain). Veterinary Parasitology 38: 249252.CrossRefGoogle Scholar
Warnes, SW and Keevil, CW (2003). Survival of Cryptosporidium parvum in faecal wastes and salad crops. In: Duffy, G (editor). Conference proceedings, Cryptosporidium parvum in Food and Water, held at Grand Hotel Malahide, Dublin January 29th 2003. Dublin: Teagasc, National Food Centre, p.15.Google Scholar
WHO (1986) Cryptosporidiosis surveillance. Weekly Epidemiology Record 59: 7273. http://www.who.int/ ctd/dracun/whodocs2.htm.Google Scholar
Yu, JR, Choi, SD and Kim, YW (2000). In vitro infection of Cryptosporidium parvum to four different cell lines. Korean Journal of Parasitology 38: 5964.CrossRefGoogle ScholarPubMed
Zorana, M, Sofija, KR and Kulisic, Z (2002). Cryptosporidium infection in weaners, bull calves and postparturient cows in the Belgrade area. Acta Veterinaria 52: 3742.CrossRefGoogle Scholar