• A nationwide surveillance study on E.coli 0157:H7 and enterobacteriaceae in Irish minced beef products

      Duffy, Geraldine; Cagney, Claire; Crowley, Helen; Sheridan, James J.; Food Safety Authority of Ireland (Teagasc, 2003-04)
      A surveillance study on prevalence and numbers of E . coli O157: H7 in minced beef (unpackaged or packaged) and beefburgers (frozen, fresh and unpackaged or packaged) was carried out over a period of 12 months in the Republic of Ireland. A total of 1533 products were tested with approximately 15 products collected from each of the 26 counties every 3 months. Mince and beefburgers were collected from both supermarkets and butcher shop outlets. A standard analysis was conducted by sample enrichment, IMS extraction and plating onto SMAC agar with confirmation by PCR. The results showed that 43 retail beef products (2.8 %) contained E .coli O157:H7. The number of E .coli O157: H7 in 21 of these samples ranged from log100.51 - 4.03 cfu g-1 ( i.e. 3 to 10,700 bacteria per gram) while in the remaining 22 the pathogen was detectable by enrichment only. There was a seasonal effect observed with 33 of 43 positive samples detected in January (n = 8), April /May(n=20) and August (n=5) and the remaining 10 positive samples detected over the other 8 months. Of the beef products testing positive, 32 were purchased from supermarkets and 11 from butcher shops. E .coli O157:H7 was recovered from 2.8% (13 / 457) of fresh packaged mince and from 1.88 % (3 / 160) of fresh unpackaged burgers purchased from butcher shops. Of the 43 isolates recovered, 41 contained the virulence genes v t1, v t2, E aeA and H lyA while the remaining 2 isolates contained only one of the vtproducing genes (v t1or v t2).
    • Recovery and identification of emerging Campylobacteraceae from food

      Duffy, Geraldine; Cagney, Claire; Lynch, Orla; Downey, Gerard (Teagasc, 01/02/2007)
      The family Campylobacteraceae includes 23 different species of Campylobacter and Arcobacter.To date, clinical and epidemiological interest has focused almost exclusively on just two of these species, C. jejuni and C. coli. Current routine examination methods for both clinical and food samples look exclusively for these two species. Recent clinical research indicates that some of the other, previously ignored Campylobacter species may be linked to human infection. The focus of this research was to develop a routine procedure which would allow recovery of all 23 species of Campylobacteraceae from food samples.