• Antibiotic resistance in foodborne pathogens

      Duffy, Geraldine; Walsh, Ciara (Teagasc, 2005-02)
      Wide-spread antibiotic resistance among bacterial pathogens is now a serious public health issue and multi-antibiotic resistance has been reported in many foodborne pathogens including Salmonella and E. coli.
    • Control of escherichia coli 0157:H7 in beefburgers

      Bolton, Declan; Byrne, Catriona; Catarame, Terese; Sheridan, James J. (Teagasc, 2001-04)
      The inactivation of E. coli O157:H7 by heating, freezing, pulsed electric field, sodium lactate, lactic acid and citric acid, alone or in combination was investigated. The industrial process for beefburger manufacture did not significantly reduce E.coli O157:H7 numbers regardless of the burger recipe and method of tempering used. Fast freezing of the burgers (to -18°C in 30 minutes as opposed to 36 hours), pulsed electric field, sodium lactate, lactic acid and citric acid, individually and in combination, did not significantly reduce E. coli O157:H7 numbers when applied at different stages throughout the beef burger manufacturing process. Beefburger safety is therefore reliant on proper storage, handling and thermal processing in the domestic or catering kitchen. The lethal effect of thermal processing may be enhanced by the addition of sodium lactate to the burger during mixing. These results are presented and discussed.
    • Determination of the presence of pathogens and anthelmintic drugs in raw milk and raw milk cheeses from small scale producers in Ireland

      Lourenco, Antonio; Fraga-Corral, Maria; De Colli, Lorenzo; Moloney, Mary; Danaher, Martin; Jordan, Kieran; Depart of Agriculture, Food and the Marine; 15/F/690 (Elsevier, 2020-04-03)
      This aim of this study was to assess the microbiological and anthelmintic drug residue risks associated with raw milk used for cheesemaking and raw milk cheese, over an 18-month period. Samples of raw milk, milk filters, curd and cheese from nine raw milk artisan cheese producers in the south of Ireland were tested. Numbers of presumptive Bacillus cereus group, Escherichia coli, Salmonella spp., Staphylococcus aureus and Listeria monocytogenes were determined. The determination of anthelmintic drug residues, including benzimidazoles, flukicides, macrocyclic lactone (avermectin and milbemycins), levamisole and morantel was also performed. Neither L. monocytogenes, nor Salmonella spp. were detected in any of the samples tested and no anthelmintic drug residues were detected. Only one of the samples did not conform with regulatory numbers for other bacteria. This survey has shown a good microbiological and residue quality (and low risk) of the raw milk cheese and raw milk used for raw milk cheese produced in Ireland. Moreover, it has shown the importance of frequent assessment of raw milk used for cheesemaking and for raw milk cheese, as it allows the identification of potential problems facilitating resolution of these issues before they cause any public health threat.
    • A European study on animal food & biomedical aspects of E.coli 0157:H7

      Duffy, Geraldine; Garvey, Patricia; Sheridan, James J.; European Union; CT98-3935 (Teagasc, 2002-02)
      Verocytotoxin producing Escherichia coli (VTEC) and, in particular, strains of serogroup O157, have emerged as significant pathogens causing a range of severe and potentially fatal illnesses. The European Union has recognised the threat posed by E coli O157:H7 and the need to devise control strategies based on an understanding of VTEC pathogenicity, transmission, survival and growth. It acknowledges the importance of informing farmers, veterinarians, food producers and health authorities so that each of these groups can act appropriately to reduce the overall hazards posed by these organisms. To contribute to the development and dissemination of effective control strategies, the European Commission funded this Concerted Action Project 1
    • Hygiene and safety of Irish beef carcasses.

      Kerr, Marie; Sheridan, James J. (Teagasc, 2002-10)
      Investigations were carried out in a number of beef abattoirs in Ireland. Information was obtained on the hygienic status of the carcasses being produced and also on their safety, using the presence of Salmonella as an indicator. The data showed that, in general, the hygiene of the carcasses being produced was of a satisfactory quality and that faecal contamination was low, as indicated by the coliform and E. coli counts. The safety of the carcasses as indicated by the presence of Salmonella was considered to be a cause for concern. The level of contamination by this pathogen of 7.6% was considered to be high and requires investigation. The majority of the Salmonella present on carcasses was S. typhimurium DT104, which is resistant to a range of antibodies. The work was part of an EU project and some results are presented from other partners.
    • A quantitative risk assessment of E.coli 0157:H7 in Irish minced beef

      Duffy, Geraldine; O'Brien, Stephen; Carney, Eimear; Butler, Francis; Cummins, Enda; Nally, Padraig; Mahon, Denise; Henchion, Maeve; Cowan, Cathal (Teagasc, 2005-02)
      A national quantitative risk assessment was undertaken for minced beef in the Republic of Ireland. The objective was to estimate the probability of E. coli O157:H7 infection from consumption of Irish beef and to investigate the parts of the beef chain contributing most to the risk posed by this pathogen.The quantitative risk assessment was broken into 3 main modules: 1) production of boxed beef trimmings; 2) processing of trimmings and burger formation and 3) retail/domestic consumption phase. Key points in each module (beef hide, beef trimmings and beef products at retail) were validated using data derived from microbiology sampling at beef abattoirs, supermarkets and butchers’ shops in Ireland.
    • Routine diagnostic tests for food-borne pathogens

      Duffy, Geraldine; Kilbride, Brendan; Fitzmaurice, Justine; Sheridan, James J. (Teagasc, 2001-01)
      Rapid techniques were developed and applied to the determination of total viable bacteria and to the detection of food borne pathogens (Listeria monocytogenes, Salmonella, Campylobacter jejuni and E. coli O157:H7). The method developed for total viable counts is based on membrane filtration and fluorescent staining and the technique can be performed and a result obtained within 20 min. The results correlate well with the standard plate count and the technique is now being implemented in Irish food factories.
    • The survival of added escherichia coli O157:H7 in natural mineral water and its products and the development of a rapid method for enumeration of the heterotrophic bacteria in natural mineral water

      Kerr, Marie; Fitzgerald, Margaret; Sheridan, James J. (Teagasc, 2000-12)
      The consumption of natural mineral water is rapidly growing and outpacing all other beverages on a global scale. In Europe, bottled water already has a bigger market share than carbonated soft drinks. Yet there is only a limited availability of information on the microbiological safety and quality of bottled natural mineral waters sold within the European Community. As natural mineral water does not receive any bacteriocidal treatment prior to bottling, the risk of pathogen contamination is a public health concern. Pathogen contamination may occur as a result of over exploitation of natural mineral water resources i.e. over abstraction by commercial bottling companies may lead to disturbance of the water table causing contaminated surface water to be drawn down into ground water supplies (Green and Green 1994). Such contamination was implicated in an outbreak of cholera associated with the consumption of bottled natural mineral water in Portugal in 1974 (Blake et al. 1977). The transport and dissemination of E. coli and enterococci in a limestone aquifer had been demonstrated by Personné et al. (1998), confirmation that E. coli can survive the transitory period from the surface to underground water supplies, thus raising the question of E. coli O157:H7 with its low infective dose < 10 cells (Willshaw et al. 1994 and Tilden et al. 1996) surviving the transitory period from surface to a natural mineral water aquifer.
    • The virulence of E. coli 0157:H7 isolated from Irish sheep and pigs to humans

      Lenahan, Mary; Sheridan, James J.; O'Brien, Stephen (Teagasc, 2008-02)
      Investigations were carried out at five sheep and five pig export abattoirs situated in the Republic of Ireland to determine the prevalence of E. coli O157:H7 in these animals at slaughter. This is the first study for the presence of E. coli O157:H7 on sheep and pigs to be carried out in Ireland. Faeces and pre- and post-chill carcass swabs were collected from pigs over a one year period between January and December 2004. Samples were collected from sheep over a 13-month period between February 2005 and February 2006. The pig study recovered E. coli O157:H7 from 0.24 % (n=4) of 1680 porcine samples while the sheep study isolated the pathogen from 2.1 % (n=33) of 1600 ovine samples. PCR analysis of E. coli O157:H7 isolates determined that they carried the virulence genes vt1, vt2, eaeA and hlyA typically associated with clinical illness in humans. The results presented indicate that Irish sheep and pigs are reservoirs for E. coli O157:H7 which may be potentially harmful to humans.