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Occurrence of Listeria species in prepacked retail sandwiches

Published online by Cambridge University Press:  15 May 2009

I. G. Wilson
Affiliation:
Northern Ireland Public Health Laboratory, Bacteria Department, Belfast City Hospital, Lisburn Road, Belfast BT9 7AD, UK
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Summary

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A survey of 725 prepacked sandwiches was conducted examining for the presence on enrichment, and by plate count, of Listeria species. Sandwiches were found to contain Listeria sp. more frequently than their component foods. Chicken, beef and bacon fillings were associated with more frequent isolation. Salad also was associated with more frequent isolation, but the increase was not significant. On enrichment, over 15% of sandwiches contained Listeria species. L. innocua and L. monocytogenes were the only species isolated by plate count at numbers ≤ 100 cfu/g (1·5% of total samples). Potentially hazardous levels of L. monocytogenes (defined as ≤ 103 cfu/g) were found in two sandwiches examined (0·3%), indicating that although Total Viable Counts (TVCs) may often be high, the risk of listeriosis to vulnerable individuals from sandwiches is relatively low. It is importent to distinguish the risk of consuming potentially hazardous levels of a pathogen in food from the risk of contracting illiness as a result of such an event.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1996

References

1.Farber, JM, Peterkin, JI.Listeria monocytogenes, a food-borne pathogen. Microbiol Rev 1991; 55: 476511.CrossRefGoogle ScholarPubMed
2.Gilbert, RJ.Provisional microbiological guidelines for some ready-to-eat foods sampled at point of sale: notes for PHLS examiners. PHLS Microbiol Dig 1992; 9: 98–9.Google Scholar
3.Roberts, D.Listeria monocytogenes and food: the UK approach. Dairy Food Environ Sanit 1994; 14: 198, 200, 202–4.Google Scholar
4.Mills, S.Bacteriological examination of sandwiches sold from petrol filling stations. Brit Food J 1989; 91: 2836.CrossRefGoogle Scholar
5. Anonymous. Northern Ireland pre-packed sandwich survey, June–September 1990. Commun Dis Environ Health Scotland 1993; 27: 38.Google Scholar
6.Hunter, PA, Hornby, H, Green, I.Cheshire Chief Environmental Health officers Food Group. The microbiological quality of pre-packed sandwiches. Brit Food J 1990; 92: 15–8.CrossRefGoogle Scholar
7.Kerr, KG, Lacey, RW.Isolation and identification of Listeria monocytogenes. J Clin Pathol 1991; 44: 624–7.CrossRefGoogle ScholarPubMed
8.Wilson, IG.Use of the IUL Countermat automatic colony counter for spiral plated total viable counts. Appl Environ Microbiol 1995; 61: 3158–60.CrossRefGoogle ScholarPubMed
9.Wilson, IG.Occurrence of Listeria species in ready to eat foods. Epidemiol Infect 1995; 115: 519–26.CrossRefGoogle ScholarPubMed
10.Lessing, MPA, Curtis, GDW, Bowler, ICJ.Listeria ivanovii infection. J infect 1994; 29: 230–1.CrossRefGoogle ScholarPubMed
11.Menudier, A, Bosiraud, C, Nicolas, J-A.Virulence of Listeria monocytogenes serovars and Listeria spp. in experimental infection of mice. J Food Protect 1991; 54: 917–21.CrossRefGoogle ScholarPubMed
12.Harvey, J, Gilmour, A.Occurrence of Listeria species in raw milk and dairy products produced in Northern Ireland. J Appl Bacteriol 1992; 72: 119–25.CrossRefGoogle ScholarPubMed
13.Lawrence, LM, Gilmour, A.A incidence of Listeria spp. and Listeria monocytogenes in a poultry processing environment and in poultry products and their rapid confirmation by multiplex PCR. Appl Environ Microbiol 1994; 60: 4600–4.CrossRefGoogle Scholar
14.Gohil, VS, Ahmed, MA, Davies, R, Robinson, RK.A research note: incidence of Listeria spp. in retail foods in the United Arab Emirates. J Food Protect 1995; 58: 102–4.CrossRefGoogle Scholar
15. Anonymous. Lanark Blue judgement questions credibility of foods experts. Environ Health News 1995; 15 December: 2.Google Scholar