3. Organizaci´ on Molecular de Pel´ıculas Delgadas Mixtas en la
3.1.5. Supporting Information: Reflection of an Anisotropic
Locating the food product responsible for human illness can be rather diffi cult for a number of reasons:
(i) only a small proportion of the human population is at risk for severe infection which requires medical attention, and thus, many infections go unreported;
(ii) an accurate recollection of all activities and foods eaten before the onset of symptoms is nearly impos-sible; and (iii) the documentation of epidemiologi-cally and genetiepidemiologi-cally related illnesses and/or contaminated food products may not be available and/or correct (CDC, 2006; Cieslack et al., 1997;
Mead et al., 1999; Rangel et al., 2005; Swaminathan et al., 2001). When attribution is possible, the CDC estimates a 2- to 3-week interval between consump-tion of contaminated food and being classifi ed as part of an E. coli outbreak (http://www.cdc.gov/ecoli/
reportingtimeline.htm). This interval includes incu-bation time, onset and progression of symptoms which require medical attention, diagnostic testing by state health authorities, and completion of the analyses required to link a patient to other isolated cases of illness, to a contaminated food product, or to an established outbreak (http://www.cdc.gov/ecoli/
reportingtimeline.htm).
PFGE, the molecular typing assay used to link human clinical and/or food isolates, is conducted by trained laboratory technicians with standardized equipment and protocols and generates distinctive DNA fragment patterns or genetic “fi ngerprints.”
Once generated, PFGE profi les are made available to other regional laboratories with access to the national supplemented with sucrose, sorbose, bile salts no. 3,
5-bromo-4-chloro-3-indolyl- -d-galactopyranoside (X-Gal), iso propyl- -d-thiogalactopyranoside (IPTG), novobiocin, and potassium tellurite. A second medium was used to confi rm the identity of suspect colonies and was composed of a phenol red base supplemented with dulcitol, l-rhamnose, d-raffi nose, or d-arabi-nose. Sorbitol-positive and -negative O157 strains were plated onto differential media consisting of MAC supplemented with sorbitol, bile salts no. 3, X-Gal, IPTG, novobiocin, and potassium tellurite.
Following incubation, the identity of suspect sorbitol-positive colonies (purple) was confi rmed using a phe-nol red base plus l-rhamnose (Possé et al., 2008).
Bacteriophages are species-specifi c viruses that, when labeled with an indicator compound (i.e., fl uo-rescent protein), can be used to detect target organ-isms among a diverse background of unrelated microfl ora. Labeled E. coli-specifi c bacteriophages infect and replicate within viable cells and can indi-cate the presence of extremely low levels of E. coli within 1 to 2 h (Goodridge et al., 1999; Tanji et al., 2004). In one study, the ability of green fl uorescent protein-labeled PP01 bacteriophage to detect E. coli O157:H7 was examined, and using an epifl uores-cence microscope, adsorption of green fl uorescent protein-PP01 to cells was observed after only 10 min (4C); maximum fl uorescence was observed after 3 h (Oda et al., 2004). Brigati et al. (2007) described the use of a recombinant phage specifi c for E. coli O157:H7, which initiates the production of N-(3-oxohexanoyl)-l-homosterine lactone (OHHL) in infected cells. Bioreporter cells carrying the Vibrio fi s-cheri lux operon were added to the reaction and emit-ted a bioluminescent signal in response to OHHL production by infected cells after as few as 4 h (Brigati et al., 2007). While these and other phage assays demonstrate potential for use in the rapid detection of E. coli O157:H7, overall sensitivity and specifi city in the presence of food components and background fl ora remain unproven. Extended enrichment proto-cols may also be necessary when using bacteriophages to detect E. coli in food samples (Goodridge et al., 1999). Additional drawbacks include bacteriophages with a very broad/narrow target host range and the eventual development of resistance by target host cells (Greer and Dilts, 1990; Loessner and Busse, 1990; McGrath et al., 2002; Summers, 2001).
Biosensors are devices associated or integrated with cellular transduction systems and include cell components and biologically or synthetically engi-neered compounds (Lazcka et al., 2007). A multitude of enzyme-, nucleic acid-, or antibody-based biosen-sor assays have been developed for use in the detec-tion of pathogens, although antibody-based assays
Allos, B. M., M. R. Moore, P. M. Griffi n, and R. V. Tauxe. 2004.
Surveillance for sporadic foodborne disease in the 21st century:
the FoodNet perspective. Clin. Infect. Dis. 38:S115–S120.
Aragon, V., K. L. Chao, and L. A. Dreyfus. 1997. Effect of cytole-thal distending toxin on F-actin assembly and cell division in Chinese hamster ovary cells. Infect. Immun. 65:3774–3780.
Arrit, F. M., J. D. Eifert, M. D. Pierson, and S. S. Sumner. 2002.
Effi cacy of antimicrobials against Campylobacter jejuni on chicken breast skin. J. Appl. Poultry Res. 11:358–366.
Arthur, T. M., T. L. Wheeler, S. D. Shackelford, J. M. Bosilevac, X. W. Nou, and M. Koohmaraie. 2005. Effects of low-dose, low-penetration electron beam irradiation of chilled beef carcass surface cuts on Escherichia coli O157:H7 and meat quality. J. Food Prot. 68:666–672.
Bacon, R. T., and J. N. Sofos. 2003. Characteristics of biological hazards in foods, p. 157–195. In R. H. Schmidt and G. E. Rodrick, Food Safety Handbook. John Wiley & Sons, Hoboken, NJ.
Bacon, R. T., J. R. Ransom, J. N. Sofos, P. A. Kendall, K. E. Belk, and G. C. Smith. 2003. Thermal inactivation of susceptible and multiantimicrobial-resistant Salmonella strains grown in the absence or presence of glucose. Appl. Environ. Microbiol.
69:4123–4128.
Barham, A. R., B. L. Barham, A. K. Johnson, D. M. Allen, J. R. Blanton, and M. F. Miller. 2002. Effects of the transporta-tion of beef cattle form feedyard to the packing plant on preva-lence levels of Escherichia coli O157 and Salmonella spp. J. Food Prot. 65:280–283.
Bari, M. L., M. I. Al–Haq, T. Kawasaki, M. Nakauma, S. Todoriki, S. Kawamoto, and K. Isshiki. 2004. Irradiation to kill Escherichia coli O157:H7 and Salmonella on ready-to-eat radish and mung bean sprouts. J. Food Prot. 67:2263–2268.
Barkocy-Gallagher, G. A., T. M. Arthur, M. Rivera–Betancourt, X. W. Nou, S. D. Shackelford, T. L. Wheeler, and M. Koohmaraie.
2003. Seasonal prevalence of Shiga toxin-producing Escherichia coli, including O157:H7 and non-O157 serotypes, and Salmonella in commercial beef processing plants. J. Food Prot. 66:1978–
1986.
Bauer, M. E., and R. A. Welch. 1996. Characterization of an RTX toxin from enterohemorrhagic Escherichia coli O157:H7. Infect.
Immun. 64:167–175.
Beatty, M. E., C. A. Bopp, J. G. Wells, K. D. Greene, N. D. Puhr, and E. D. Mintx. 2004. Enterotoxin-producing Escherichia coli O169:H41, United States. Emerg. Infect. Dis. 10:518–521.
Begue, R. E., D. I. Mehta, and U. Bleckler. 1998. Escherichia coli and the hemolytic-uremic syndrome. South. Med. J. 91:798–
804.
Bell, B. P., M. Goldoft, P. M. Griffi n, M. A. Davis, D. C. Gordon, P. I. Tarr, C. A. Bartleson, J. H. Lewis, T. J. Barrett, J. G. Wells, R. Baron, and J. Kobayashi. 1994. A multistate outbreak of Escherichia coli O157:H7 associated with bloody diarrhea and hemolytic-uremic syndrome from hamburgers—the Washington experience. JAMA 272:1349–1353.
Bell, R. G. 1997. Distribution and sources of microbial contamina-tion on beef carcasses. J. Appl. Microbiol. 82:292–300.
Bellini, E. M., W. P. Elias, T. A. T. Gomes, T. L. Tanaka, C. R. Taddei, R. Huerta, F. Navarro-Garcia, and M. B. Martinez.
2005. Antibody response against plasmid–encoded toxin (Pet) and the protein involved in intestinal colonization (Pic) in children with diarrhea produced by enteroaggregative Escherichia coli.
FEMS Immunol. Med. Microbiol. 43:259–264.
Belongia, E. A., P.-H. Chyou, R. T. Greenlee, G. Perez-Perez, W. F. Bibb, and E. O. DeVries. 2003. Diarrhea incidence and farm-related risk factors for Escherichia coli O157:H7 and Campylobacter jejuni antibodies among rural children. J. Infect.
Dis. 187:1460–1468.
CDC database (http://www.cdc.gov/pulsenet/whatis/
htm). PulseNet and FoodNet generate and manage the PFGE profi les of human clinical and food-derived isolates, respectively, and the databases are routinely compared (http://www.cdc.gov/pulsenet/whatis/htm).
The admitted limitations of PFGE analysis include extensive time requirements, variation between tech-nicians and/or human error, the generation of mea-surements that do not relate to actual phylogenetic homology, the genetic instability of bacteria, and an inability to generate profi les for all strains (Davis et al., 2003; http://www.cdc.gov/pulsenet/whatis.
htm). The limitations of PulseNet include the dissimi-lar prioritization, and a lack of fi nancial and informa-tional resources within local, state, and federal agencies (http://www.cdc.gov/pulsenet/whatis.htm).
Future improvements may include the update and streamlining of current PFGE protocols, the adoption of new subtyping technologies, and an increased number of participants and contributors with an enhanced degree of communication (http://www.cdc.
gov/pulsenet/whatis.htm).
Despite the inability of routine microbiological testing to confi rm the safety of food products and the limitations of current surveillance programs, Rangel et al. (2005) evaluated the epidemiology and incidence of E. coli O157:H7 outbreaks between 1982 and 2002 and found that the annual incidence of outbreaks remained fairly constant, while the median size of each outbreak has decreased over time. The documentation of smaller and smaller outbreaks is indicative of successful surveillance efforts that include the refi nement and standardiza-tion of laboratory techniques, improved reporting and sharing of information, and induction of more regional testing facilities which cater to a larger proportion of the national population. In addition to the surveillance of human clinical cases, the rou-tine testing of environmental and food samples has led to the recall of hundreds of millions of pounds of potentially contaminated food products, which may have led to many illnesses, hospitalizations, and deaths.
REFERENCES
Acuff, G. R. 2005. Chemical decontamination strategies for meat, p. 350–363. In J. N. Sofos, Improving the Safety of Fresh Meat.
CRC Press, Boca Raton, FL.
Alam, M. J., and L. Zurek. 2004. Association of Escherichia coli O157:H7 with housefl ies on a cattle farm. Appl. Environ.
Microbiol. 70:7578–7580.
Alexander, E. R., J. Boase., M. Davis, L. Kirchner, C. Osaki, T. Tanino, P. Samadpour, M. Goldoft, P. Bradley, B. Hinton, P. Tighe, B. Pearson, and G. R. Flores. 1995. Escherichia coli O157:H7 outbreak linked to commercially distributed dry-cured salami. JAMA 273:985–986.
G. F. Mayhew, J. Gregor, N. W. Davis, H. A. Kirkpatrick, M. A. Goeden, D. J. Rose, B. Mau, and Y. Shao. 1997. The complete genome sequence of Escherichia coli K-12. Science 227:1453–1462.
Boerlin, P., S. A. McEwen, F. Boerlin-Petzold, J. B. Wilson, R. P. Johnson, and C. L. Gyles. 1999. Associations between viru-lence factors of Shiga toxin-producing Escherichia coli and dis-ease in humans. J. Clin. Microbiol. 37:497–503.
Borczyk, A. A., N. Harnett, M. Lombos, and H. Lior. 1990. False positive identifi cation of Escherichia coli O157 by commercial latex agglutination tests. Lancet 336:946–947.
Boyce, T. G., A. G. Pemberton, J. G. Wells, and P. M. Griffi n.
1995. Screening for Escherichia coli O157:H7–a nationwide survey of clinical laboratories. J. Clin. Microbiol. 33:3275–
3277.
Brashears, M., G. Loneragan, and S. Younts–Dahl. 2005.
Controlling microbial contamination on the farm: an overview, p. 156–174. In J. N. Sofos (ed.), Improving the Safety of Fresh Meat. CRC Press, Boca Raton FL.
Bricher, J. L. 2003. Technology round-up: innovations in micro-bial interventions. Food Saf. Mag. 11:29–33.
Brigati, J. R., S. A. Ripp, C. M. Johnson, P. A. Iakova, P. Jegier, and G. S. Sayler. 2007. Bacteriophage-based bioluminescent bioreporter for the detection of Escherichia coli O157:H7.
J. Food Prot. 70:1386–1392.
Brooks, J. T., S. Y. Rowe, P. Shillam, D. M. Heltzel, S. B. Hunter, L. Slutsker, R. M. Hoekstra, and S. P. Luby. 2001. Salmonella Typhimurium infections transmitted by chlorine–pretreated clo-ver sprout seeds. Am. J. Epidemiol. 154:1020–1028.
Brunder, W., H. Schmidt, and H. Karch. 1996. KatP, a novel cata-lase-peroxidase encoded by the large plasmid of enterohaemor-rhagic Escherichia coli O157:H7. Microbiology 142:3305–
3315.
Buchanan, R. L., and M. P. Doyle. 1997. Foodborne disease sig-nifi cance of Escherichia coli O157:H7 and other enterohemor-rhagic E. coli. Food Technol. 51:69–76.
Buchanan, R. L., and S. G. Edelson. 1999. Effect of pH–depen-dent, stationary phase acid resistance on the thermal tolerance of Escherichia coli O157:H7. Food Microbiol. 16:447–
458.
Callaway, T. R., R. C. Anderson, T. S. Edrington, K. J. Genovese, T. L. Poole, R. B. Harvey, D. J. Nisbet, and K. D. Dunkley. 2005.
Probiotics, vaccines, and other interventions for pathogen con-trol in animals, p. 192–213. In J. N. Sofos (ed.), Improving the Safety of Fresh Meat. CRC Press, Boca Raton, FL.
Callaway, T. R., R. C. Anderson, T. S. Edrington, K. J. Genovese, K. M. Bischoff, T. L. Poole, Y. S. Jung, R. B. Harvey, and D. J. Nisbet. 2004. What are we doing about Escherichia coli O157:H7 in cattle? J. Anim. Sci. 82:93–99.
CDC. 1995a. Escherichia coli O157:H7 outbreak linked to com-mercially distributed dry-cured salami—Washington and California, 1994. MMWR Morb. Mortal. Wkly. Rep. 44:157–
159.
CDC. 1995b. Community outbreak of hemolytic uremic syndrome attributable to Escherichia coli O111:NM—South Australia, 1995. MMWR Morb. Mortal. Wkly. Rep.44:550–551.
CDC. 1996. Outbreak of Escherichia coli O157:H7 infection:
Georgia and Tennessee, June 1995. MMWR Morb. Mortal.
Wkly. Rep. 45:249–251.
CDC. 1997. Outbreaks of Escherichia coli O157:H7 infection and cryptosporidiosis associated with drinking unpasteurized apple cider—Connecticut and New York, October 1996. MMWR Morb. Mortal. Wkly. Rep. 46:4–8.
CDC. 2000. Outbreak of Escherichia coli O157:H7 infection asso-ciated with eating fresh cheese curds. MMWR Morbid. Mortal.
Wkly. Rep. 49:911–913.
Berger, S. A., N. A. Young, and S. C. Edberg. 1989. Relationship between infectious diseases and human blood type. Eur. J. Clin.
Microbiol. Infect. Dis. 8:681–689.
Bergwerff, A. A., and F. van Knapen. 2006. Surface plasmon reso-nance biosensors for detection of pathogenic microorganisms:
strategies to secure food and environmental safety. J. AOAC Int.
89:826–831.
Berin, M. C., A. Darfeuille-Michaud, L. J. Egan, Y. Miyamoto, and M. F. Kagnoff. 2002. Role of EHEC O157:H7 virulence factors in the activation of intestinal epithelial cell NF- and MAP kinase pathways and the upregulated expression of inter-leukin 8. Cell. Microbiol. 4:635–647.
Besser, R. E., P M. Griffi n, and L. Slutsker. 1999. Escherichia coli O157:H7 gastroenteritis and the hemolytic uremic syndrome:
an emerging infectious disease. Annu. Rev. Med. 50:355–367.
Besser, R. E., S. M. Lett, J. T. Weber, M. P. Doyle, T. J. Barrett, J. G. Wells, and P. M. Griffi n. 1993. An outbreak of diarrhea and hemolytic uremic syndrome from Escherichia coli O157:H7 in fresh-pressed apple cider. JAMA 269:2217–2220.
Beuchat, L. R. 1998. Surface decontamination of fruits and vege-tables eaten raw: a review. WHO/FSF/FOS/98.2. World Health Organization, Food Safety Unit.
Beuchat, L. R., and J. H. Ryu. 1997. Produce handling and pro-cessing practices. Emerg. Infect. Dis. 3:459–465.
Beutin, L., M. A. Montenegro, I. Orskov, F. Orskov, J. Prada, S. Zimmermann, and R. Stephan. 1989. Close association of verotoxin Shiga-like toxin production with enterohemolysin production in strains of Escherichia coli. J. Clin. Microbiol.
27:2559–2564.
Beutin, L., S. Aleksic, S. Zimmermann, and K. Gleier. 1994.
Virulence factors and phenotypical traits of verotoxigenic strains of Escherichia coli isolated from human patients in Germany.
Med. Microbiol. Immun. 183:13–21.
Bielaszewska, M., and H. Karch. 2000. Non–O157 Shiga toxin verocytotoxin-producing Escherichia coli strains: epidemiolo-gical signifi cance and microbiological diagnosis. World J. Microbiol. Biotech. 16:711–718.
Bielaszewska, M., J. Janda, K. Blahova, H. Minarikova, E. Jikova, M. A. Karmali, J. Laubova, J. Sikulova, M. A. Preston, R. Khakhria, H. Karch, H. Klazarova, and O. Nyc. 1997.
Human Escherichia coli O157:H7 infection associated with the consumption of unpasteurized goat’s milk. Epidemiol. Infect.
119:299–305.
Bilge, S. S., C. R. Clausen, W. Lau, and S. L. Moseley. 1989.
Molecular characterization of a fi mbrial adhesin, F1845, medi-ating diffuse adherence of diarrhea–associated Escherichia coli to HEp-2 cells. J. Bacteriol. 171:4281–4289.
Bilge, S. S., J. M. Apostol, Jr., K. J. Fullner, and S. L. Moseley.
1993. Transcriptional organization of the F1845 fi mbrial adhesin determinant of Escherichia coli. Mol. Microbiol.
7:993–1006.
Blanco, J. E., M. Blanco, M. P. Alonso, A. Mora, G. Dahbi, M. A. Coira, and J. Blanco. 2004. Serotypes, virulence genes, and intimin types of Shiga toxin verotoxin-producing Escherichia coli isolates from human patients: prevalence in Lugo, Spain, from 1992 through 1999. J. Clin. Microbiol. 43:311–319.
Blanco, J., M. Blanco, M. P. Alonso, J. E. Blanco, E. A. González, and J. I. Garabal. 1992. Characteristics of haemolytic Escherichia coli with particular reference to production of cyto-toxic necrotizing factor type 1 (CNF1). Res. Microbiol.
143:869–878.
Blaser, M. J., J. Cravens, B. W. Powers, F. M. Laforce, and W. L. L. Wang. 1979. Campylobacter enteritis associated with unpasteurized milk. Am. J. Med. 67:715–718.
Blattner, F. R., F. Plunkett III, C. A. Bloch, N. T. Perna, V. Burland, M. Riley, J. Collado-Vides, J. D. Glasner, C. K. Rode,
shiga toxin–producing E. coli strains in neonatal pigs. Infect.
Immun. 71:6526–6533.
DeVinney, R., M. Stein, D. Reinscheid, A. Abe, S. Ruschkowski, and B. B. Finlay. 1999. Enterohemorrhagic Escherichia coli O157:H7 produces Tir, which is translocated to the host cell membrane but is not tyrosine phosphorylated. Infect. Immun.
67:2389–2398.
DeVinney, R., J. L. Puente, A. Gauthier, D. Goosney, and B. B. Finlay. 2001. Enterohaemorrhagic and enteropathogenic Escherichia coli use a different Tir-based mechanism for pedestal formation. Mol. Microbiol. 41:1445–1458.
Diez-Gonzalez, F. 2005. The use of diet to control pathogens in animals, p. 175–191. In J. N. Sofos (ed.), Improving the Safety of Fresh Meat. CRC Press, Boca Raton, FL.
Doyle M., and V. Padhye. 1989. Escherichia coli, p. 236–282. In M. P. Doyle (ed.), Foodborne Bacterial Pathogens. Marcel Dekker Inc., New York, NY.
Doyle, M. P., and D. J. Roman. 1982. Prevalence and survival of Campylobacter jejuni in unpasteurized milk. Appl. Environ.
Microbiol. 44:1154–1158.
Duffy, L. L., F. H. Grau, and P. B. Vanderlinde. 2000. Acid resis-tance of enterohaemorrhagic and generic Escherichia coli associ-ated with foodborne disease and meat. Int. J. Food Microbiol.
60:83–89.
Elliott, S. J., L. A. Wainwright, T. K. McDaniel, K. G. Jarvis, Y. Deng, L. Lai, B. P. McNamara, M. S. Donnenberg, and J. B. Kaper. 1998. The complete sequence of the locus of entero-cyte effacement LEE from enteropathogenic Escherichia coli E2348/69. Mol. Microbiol. 28:1–4.
Elliott, S. J., S. W. Hutcheson, M. S. Dubois, J. L. Mellies, L. A. Wainwright, M. Batchelor, G. Frankel, S. Knutton, and J. B. Kaper. 1999. Identifi cation of CesT, a chaperone for the type III secretion of Tir in enteropathogenic Escherichia coli.
Mol. Microbiol. 33:1176–1189.
Entis, P., D. Y. C. Fung, M. W. Griffi ths, L. McIntre, S. Russell, and A. N. Sharpe. 2001. Rapid methods for detection, identifi cation, and enumeration, p. 89–126. In F. Pouch and K. Ito (ed.), Compendium of Methods for the Microbial Examination of Foods, 4th ed. American Public Health Association, Washington, DC.
Falkow, S. 1996. The evolution of pathogenicity in Escheri-chia coli, Shigella, and Salmonella, p. 2723–2769. In F. C. Neidhardt (ed.), Escherichia coli and Salmonella: Cellular and Molecular Biology, 2nd ed. American Society for Microbiology. Washington, DC.
Farber, J. M. 1996. An introduction to the hows and whys of molecular typing. J. Food Prot. 59:1091–1101.
Foley, D., M. Euper, F. Caporaso, and A. Prakash. 2004. Irradia-tion and chlorinaIrradia-tion effectively reduces Escherichia coli O157:H7 inoculated on cilantro (Coriandrum sativum) with-out negatively affecting quality. J. Food Prot. 67:2092–
2098.
Frankel, G., A. D. Phillips, I. Rosenshine, G. Dougan, J. B. Kaper, and S. Knutton. 1998. Enteropathogenic and enterohemorrhagic Escherichia coli: more subversive elements. Mol. Microbiol.
30:911–921.
Fratamico, P. N., L. K. Bagi, and T. Pepe. 2000. A multiplex poly-merase chain reaction assay for rapid detection and identifi ca-tion of Escherichia coli O157:H7 in foods and bovine feces.
J. Food Prot. 63:1032–1037.
Fratamico, P. M., A. Gehring, J. Karns, and J. van Kessel. 2005.
Detecting pathogens in cattle and meat, p. 24–55. In J. N. Sofos (ed.), Improving the Safety of Fresh Meat. CRC Press, Boca Raton, FL.
Friedrich, A. W., M. Bielaszewska, W. L. Zhang, M. Pulz, T. Kuczius, A. Ammon, and H. Karch. 2002. Escherichia coli CDC. 2001a. Outbreaks of Escherichia coli O157:H7 infections
among children associated with farm visits—Pennsylvania and Washington, 2000. MMWR Morb. Mortal. Wkly. Rep. 50:293–
297.
CDC. 2001b. Outbreaks of Escherichia coli O157:H7 infection associated with eating alfalfa sprouts—Michigan and Virginia.
MMWR Morb. Mortal. Wkly. Rep. 46:741–744.
CDC. 2002, Multistate outbreak of Escherichia coli O157:H7 infections associated with ground beef—United States, June–
July, 2002. MMWR Morb. Mortal. Wkly. Rep. 51:637–639.
CDC. 2006. Surveillance for foodborne-disease outbreaks—
United States, 1998–2002. MMWR Morb. Mortal. Wkly. Rep.
55:1–34.
CDC. 2007. Laboratory-confi rmed non-O157 Shiga toxin—
producing Escherichia coli—Connecticut, 2000–2005. MMWR Morb. Mortal. Wkly. Rep. 56:29–31.
Chapman, P. A., C. A. Siddon, P. M. Zadik, and L. Jewes. 1991.
An improved selection medium for the isolation of Escherichia coli O157. J. Med. Microbiol. 35:107–110.
Childs, K. D., C. A. Simpson, W. Warren–Serna, G. Bellenger, B. Centrella, R. A. Bowling, J. Ruby, J. Stefanek, D. J. Vote, T. Choat, J. A. Scanga, J. N. Sofos, G. C. Smith, and K. E. Belk.
2006. Molecular characterization of Escherichia coli O157:H7 hide contamination routes: feedlot to harvest. J. Food Prot.
69:1240–1247.
Cieslak, P. R., S. J. Noble, D. J. Maxson, L. C. Empey, O. Ravenholt, G. Legarza, J. Tuttle, M. P. Doyle, T. J. Barrett, J. G. Wells, A. M. McNamara, and P. M. Griffi n. 1997. Hamburger-associated Escherichia coli O157:H7 infection in Las Vegas: a hidden epidemic. Am. J. Public Health 87:176–180.
Code of Federal Regulations. 2001. Title 9, chapter III, Food Safety and Inspection Service, Department of Agriculture, parts 300–
592. Document 9CFR300–592. U.S. Government Printing Offi ce, Washington, DC.
Code of Federal Regulations. 2002. Title 21, chapter I, Food and Drug Administration, Department of Health and Human Services, parts 1–1299. Document 21CFR1–1299. U.S.
Government Printing Offi ce, Washington, DC.
Collinson, S. K., L. Emody, T. J. Trust, and W. W. Kay. 1992. Thin aggregative fi mbriae from diarrheagenic Escherichia coli.
J. Bacteriol. 174:4490–4495.
Cookson, S. T., and J. P. Nataro. 1996. Characterization of HEp-2 cell projection formation induced by diffusely adherent Escherichia coli. Microb. Pathog. 21:421–434.
Cords, B. R., S. L. Burnett, J. Hilgren, M. Finley, and J. Magnuson.
2005. Sanitizers: halogens, surface-active agents, and peroxides, p. 507–572. In P. M. Davidson, J. N. Sofos, and A. L. Branen (ed.), Antimicrobials in Food, 3rd ed. Taylor and Francis, Boca Raton, FL.
Cutter, C. N., W. J. Dorsa, and G. R. Siragusa. 1997. Parameters affecting the effi cacy of spray washes against Escherichia coli O157:H7 and fecal contamination on beef. J. Food Prot.
60:614–618.
Dallas, W. S., and S. Falkow. 1980. Amino acid sequence homol-ogy between cholera toxin and Escherichia coli heat–labile toxin. Nature 288:499–501.
Davidson, P. M., and M. A. Harrison. 2002. Resistance and adap-tation to food antimicrobials, sanitizers, and other process con-trols. Food Tech. 56:69–78.
Davis, M. A., D. D. Hancock, T. E. Besser, and D. R. Call. 2003.
Evaluation of pulsed-fi eld gel electrophoresis as a tool for deter-mining the degree of genetic relatedness between strains of Escherichia coli O157:H7. J. Clin. Microbiol. 41:1843–1849.
Dean-Nystrom, E. A., A. R. Melton-Celsa, J. F. L. Pohlanz, H. W. Moon, and A. D. O’Brien. 2003. Comparative pathoge-nicity of Escherichia coli O157 and intimin-negative non-O157
Guth, B. E. C., S. Ramos, A. M. F. Cerqueira, J. R. C. Andrade, and T. A. T. Gomes. 2002. Phenotypic and genotypic character-istics of Shiga toxin-producing Escherichia coli strains isolated from children in Sao Paulo, Brazil. Mem. Inst. Oswaldo Cruz 97:1085–1089.
Hadley, P. J., J. S. Holder, and M. H. Hinton. 1997. Effects of fl eece soiling and skinning method on the microbiology of sheep carcasses. Vet. Rec. 140:570–574.
Hajna, A. A. 1955. A new enrichment broth medium for gram-negative organisms of the intestinal group. Public Health Lab.
13:83–89.
Hajra, T. K., P. K. Bag, S. C. Das, S. Mukherjee, A. Khan, and T. Ramamurthy. 2007. Development of a simple latex agglutina-tion assay for detecagglutina-tion of Shiga toxin-producing Escherichia coli (STEC) by using polyclonal antibody against STEC. Clin.
Vacc. Immun. 14:600–604.
Hammes, W. P., A. Bantleon, and S. Min. 1990. Lactic acid bacte-ria in meat fermentation. FEMS Microbiol. Rev. 87:165–174.
Hao, Y. Y., and R. E. Brackett. 1993. Growth of Escherichia coli O157:H7 in modifi ed atmosphere. J. Food Prot. 56:330–332.
Hara-Kudo, Y., H. Konuma, M. Iwaki, F. Kasuga, Y. Sugita–
Konishi, Y. Itoh, and S. Kumagai. 1997. Potential hazard of rad-ish sprouts as a vehicle of Escherichia coli O157:H7. J. Food Prot. 60:1125–1127.
Hardin, M. D., G. R. Acuff, L. M. Lucia, J. S. Oman, and J. W. Savell. 1995. Comparison of methods for decontamination of beef carcass surfaces. J. Food Prot. 58:368–374.
Hartland, E. L., M. Batchelor, R. M. Delahay, C. Hale, S. Matthews, G. Dougan, S. Knutton, I. Connerton, and G. Frankel. 1999. Binding of intimin from enteropathogenic
Hartland, E. L., M. Batchelor, R. M. Delahay, C. Hale, S. Matthews, G. Dougan, S. Knutton, I. Connerton, and G. Frankel. 1999. Binding of intimin from enteropathogenic