title: Nationwide prevalence and risk factors for faecal carriage of Escherichia coli O157 and O26 in very young calves and adult cattle at slaughter in New Zealand.
abstract: Nationwide prevalence and risk factors for faecal carriage of Escherichia coli O157 and O26 in cattle were assessed in a 2-year cross-sectional study at four large slaughter plants in New Zealand. Recto-anal mucosal swab samples from a total of 695 young (aged 4-7 days) calves and 895 adult cattle were collected post-slaughter and screened with real-time polymerase chain reaction (PCR) for the presence of E. coli O157 and O26 [Shiga toxin-producing E. coli (STEC) and non-STEC]. Co-infection with either serogroup of E. coli (O157 or O26) was identified as a risk factor in both calves and adult cattle for being tested real-time PCR-positive for E. coli O157 or O26. As confirmed by culture isolation and molecular analysis, the overall prevalence of STEC (STEC O157 and STEC O26 combined) was significantly higher in calves [6·0% (42/695), 95% confidence interval (CI) 4·4-8·1] than in adult cattle [1·8% (16/895), 95% CI 1·1-3·0] (P < 0·001). This study is the first of its kind in New Zealand to assess the relative importance of cattle as a reservoir of STEC O157 and O26 at a national level. Epidemiological data collected will be used in the development of a risk management strategy for STEC in New Zealand.
authors.affiliation: mEpiLab,Hopkirk Research Institute,Massey University,Palmerston North,New Zealand.
authors.forename: P
authors.initials: P
authors.lastname: Jaros
authors.affiliation: AgResearch Ltd,Hopkirk Research Institute,Palmerston North,New Zealand.
authors.forename: A L
authors.initials: AL
authors.lastname: Cookson
authors.affiliation: mEpiLab,Hopkirk Research Institute,Massey University,Palmerston North,New Zealand.
authors.forename: A
authors.initials: A
authors.lastname: Reynolds
authors.affiliation: mEpiLab,Hopkirk Research Institute,Massey University,Palmerston North,New Zealand.
authors.forename: D J
authors.initials: DJ
authors.lastname: Prattley
authors.affiliation: Ministry for Primary Industries,Wellington,New Zealand.
authors.forename: D M
authors.initials: DM
authors.lastname: Campbell
authors.affiliation: Ministry for Primary Industries,Wellington,New Zealand.
authors.forename: S
authors.initials: S
authors.lastname: Hathaway
authors.affiliation: mEpiLab,Hopkirk Research Institute,Massey University,Palmerston North,New Zealand.
authors.forename: N P
authors.initials: NP
authors.lastname: French
mesh_terms: D000003:Abattoirs; D000818:Animals; D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D002417:Cattle; D003430:Cross-Sectional Studies; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology*; D005260:Female; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D015995:Prevalence; D060888:Real-Time Polymerase Chain Reaction; D012007:Rectum / Q000382:microbiology; D012307:Risk Factors; D065288:Serogroup; D054323:Shiga-Toxigenic Escherichia coli / Q000145:classification / Q000302:isolation & purification*
keywords: Emerging infections; Shiga-like toxin-producing E. coli; food safety; infectious disease epidemiology; zoonoses