ENTEROHEMORRHAGIC ESHERICHIA COLI (EHEC) AND ENVIRONMENTCOLI(EHEC) AND ENVIRONMENT

Farm animals, such as cattle, sheep, goats and potentially pigs are carriers and excretors of EHEC (Caprioli et al., 2005; Rioset al., 1999). Direct contact with animals or feed and their uncooked or partially cooked meat is the main transmission route to humans (Levineet al.1993). Currently there are additional recognized environmental sources of infection and contamination: a) biotic (e.g., flies, rodents, birds and wildlife) (Miko et al., 2009; Caprioli et al., 2005) and b) abiotic factors (e.g., pasture and water) (Ogden et al., 2002; Thranet al., 2001; Ogdenet al., 2001) (Figure 2.9.1).

2.9.1ClassificationofhumanpathogenicE.coli. nameHostHumandiseaseAnimaldiseaseZoonosesE.coliserogroup (examples) E.coliHumans,pigs, sheep,goats, cattle,dogs,and horses Choleriformenteritis(without fever),traveler’sdiarrheaEnteritisin newbornand young

–E.coliO26:H32 E. PEC)Humans,rabbits, dogs,catsand horses

Causativeagentofdiarrhea, enteritisininfantsEnteritis?E.coliO26:H11 E.coliHumans(only)Dysenterylikecolitis–E.coliO28ac,O112ac, O124,O136,O143, O144,O152,andO164 E. HEC)Humans,cattle, goatsandother ungulates Hemolytic-uremicsyndrome, hemorrhagiccolitis,thrombotic thrombocytopenicpurpura

Hemorrhagic colitis+E.coliO157:[H7],O26: H11/NM E. AEC)Humans(only)Chronicenteritiswithoutfever?–E.coliO64:H4 adherentE. EC)Humans,calves andpigsEnteritisandurinarytrack infection?–E.coliF1845+

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A Swedish study performed on carrier calves that shed Enterohemorrhagic Esherichia coli (EHEC) revealed that those kept in a cowshed during the summer remained positive for four months after detection, while calves released to graze on pasture were pathogen free. The persistence of the pathogen in cowshed calves indicates a regular re-infection (Jonssonet al., 2001).

Czajkowskaet al., (2008) looked at the survival of EHEC vs. environmentalE. coliin wastewater and activated sludge of dairy sewage treatment plants during autumn-winter (temperature∼6°C) and spring-summer (temperature∼24°C). In activated sludge,E. coliO157:H7 bacteria were not detected (by direct plating method) after 21–28 days, and in dairy wastewater and activated sludges after 21–25 days.

EnvironmentalE. coli(non-pathogenic) survived longer: 35–42 days in activated sludge and 25–28 days in wastewater with activated sludges. However, these authors recommended based on sufficiently the extended persistence of EHEC in activated sludge, a thorough required treatment including disinfection prior to utilization of sludge as a soil fertilizer.

Wildlife meat from deer, wild boar, and hare was assessed as a potential carriers ofE. coli(EHEC) by Mikoet al.(2009). Based on genetic analysis, 32.8% of high-level virulence associated genes in humans were present in experimental isolates indicating that wild animals represent a reservoir for and a potential source of human pathogenic EHEC strains.

An additional way of dispersal and transmission was observed in beef slaughter by Stopforth et al.

(2006). Preevisceration of carcasses washing prior to bung bagging during beef slaughter may allow pooling of cleanse water in the rectal area and consequent spread of potential pathogens. Surface sampling from the postwash bagging procedure revealed a 58.3% incidence rate of EHEC compared to 35 % from prewash bagging suggesting prewash as a much better practice for the control of pathogen Figure 2.9.1. E. coli(EHEC) ecology and environmental aspects

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contamination, originating from the rectal area of carcasses. Feriancet al.(2002) looked atE. coliisolates from the Danube and Moravia rivers (Slovakia) and compared these isolates to clinical ones (collected from urinary track disease). Molecular analysis of both river and clinical isolates revealed stx2gene carried on plasmid, a characteristic of enterohemorrhagic E. coli(EHEC) strains. The authors hinted at a possible health risk for bathers from direct contact with untreated river water. Finally, the Mediterranean fruit fly (Ceratitis capitata), a cosmopolitan pest of commercial and wild fruits, was artificially contaminated (through feed solution and enriched fecal material) with GFP (green fluorescence protein)-taggedE. coli.

Flies inoculated with GFP-tagged E. coli harbored the bacteria for up to 7 days after initial contamination. Flies feeding on fruits were capable of transmitting the GFP tagged E. coli to intact apples, as were female flies that laid their eggs in fruit by puncturing the skin with their ovipositors and injecting batches of eggs into the wounds. Washing of contaminated apples with tap water did not eliminate the inoculated E. coli, revealing deeper internal inoculation of these bacteria by fruit fly into the fruit’s internal tissues (Selaet al., 2005).

2.9.2 REFERENCES

Caprioli, A., Morabito, S., Brugère, H. & Oswald, E. (2005) EnterohaemorrhagicEscherichia coli: emerging issues on virulence and modes of transmission.Vet. Res.36, 289–311.

Czajkowska, D., Boszczyk-Maleszak H., Sikorska, I.R. & Sochaj, A. (2008) Studies on the survival of enterohemorrhagic and environmentalEscherichia colistrains in wastewater and in activated sludges from dairy sewage treatment plants.Pol. J. Microbiol.57, 165–171.

Ferianc, P., Harichova, J., Proksova, M., Krepsova, K., Chovanova, K. & Toth, D. (2002) The surface river water and clinical Escherichia coliisolates: Characteristics, diversity and epidemiological significance. Biologia57, 321–334.

Jonsson, M.E., Aspan, A., Eriksson, E., Vagsholm, I. (2001) Persistence of verocytotoxin producingEscherichia coli O157:H7 in calves kept on pasture and in calves kept indoors during the summer months in a Swedish dairy herd.Int. J. Food Microbiol.66, 55–61.

Levine, M.M, Ferreccio, C., Prado, V., Cayazzo, M., Abrego, P.et al.(1993) Epidemiologic studies ofEscherichia coli diarrheal infections in a low socioeconomic level peri-urban community in Santiago, Chile.Am. J. Epidemiol.138, 849–869.

McDowell, D.A. & Sheridan, J.J. (2001) Survival and growth of Vero cytotoxin-producingE. coliin the environment.

In: Duffy G., Garvey P., McDowell D. (Eds.), VerocytotoxigenicEscherichia coli, Food & Nutrition Press Inc., Trumbull, 2001, pp. 279–304.

Miko, A., Pries, K., Haby, S., Steege, K., Albrecht, N.et al.(2009) Assessment of Shiga Toxin-ProducingEscherichia coliIsolates from Wildlife Meat as Potential Pathogens for Humans.Appl. Environ. Microbiol.75, 6462–6470.

Ogden, I.D., Fenlon, D.R., Vinten, A.J.A. & Lewis, D. (2001) The fate ofEscherichia coliO157 in soil and its potential to contaminate drinking water.Int. J. Food Microbiol.66, 111–117.

Ogden, I.D., Hepburn, N.F., MacRae, M., Strachan, N.J., Fenlon, D.R.et al.(2002) Long-term survival ofEscherichia coliO157 on pasture following an outbreak associated with sheep at a scout camp.Lett. Appl. Microbiol.34, 100–104.

Rios, M., Prado, V., Trucksis, M., Arellano, C., Borie, C. et al. (1999) Clonal diversity of chilean isolates of enterohemorrhagic Escherichia coli from patients with hemolytic-uremic syndrome, asymptomatic subjects, animal reservoirs, and food products.J. Clin. Microbiol.37, 778–781.

Sela, S. Nestel, D., Pinto, R. Nemny-Lavy, E. & Bar-Joseph, M. (2005) Mediterranean fruit fly as a potential vector of bacterial pathogens.Appl. Environ. Microbiol.71, 4052–4056.

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Thran, B.H., Hussein, H.S., Hall, M.R. & Khaiboullina, S.F. (2001) Shiga toxin-producingEscherichia coliin beef heifers grazing an irrigated pasture.J. Food Prot.64, 1613–1616.

Tschape, H. & Fruth, A. (2001) Enterohemorrhagic Escherichia coli. Contrib Microbiol 8 (Emerging Bacterial Pathogens), 1–11.

Whipp, S.C., Rasmussen, M. A. & Cray, W.C.Jr. (1994) Animals as a source ofEscherichia colipathogenic for human beings.J. Am. Vet. Med. Assoc.204, 1168–1175.

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Chapter 2.10 Erysipeloid

[ERYSIPELOTHRIX RHUSIOPATHIAE]

Erysipelothrix rhusiopathiae is a rod shaped gram-positive, non-motile, non-spore forming, facultative aerobic bacterium that does not contain endotoxin. Erysipelothrix rhusiopathiae has a worldwide distribution in nature and can be found in soil and decomposing vegetation (Timofeevaet al., 1978). It is primarily considered an animal pathogen, causing a disease known as erysipelas in animals and erysipeloid in humans. Pigs are most commonly affected, but cases have been reported in other animals such as birds (mainly in turkeys and ducks), sheep, fish, and reptiles (Brooke and Riley, 1999; Mutalib et al., 1993; Mutalibet al. 1995; Anonymous, 1946). In pigs, the disease is known as“diamond skin disease.”Less frequent animal sources of transmission to humans are: lambs, horses, cattle, dogs, mice, rats and fur-bearing animals (Timofeeva and Golovacheva, 1959; Popugalio et al., 1983). The human disease called erysipeloid displays the following symptoms: inflammation with edema and hemorrhages on hand and fingers, itch without pus and fever. Occasional lymphangitis but rarely arthritis of joints and endocarditis may occur (Booet al., 2003).