E.coli (STEC) research
STEC science programme
The STEC science programme is intended to identify reservoirs and sources of E. coli, quantify any human health risk, and to identify, implement, and evaluate effective control measures.
Research projects and reports
The following projects and reports for shiga toxin-producing E.coli include attribution, baseline food and environmental surveys, growth and inactivation kinetics, and control measures.
This document reports on a recent survey for pYV-positive Y. enterocolitica (YeP+) on retail raw pork using a new rapid and sensitive method developed at ESR to both detect (presence/absence) and enumerate (by most probable number method) this pathogen.
There is variability in the methods used by clinical laboratories in New Zealand to isolate and
identify the pathogens (Campylobacter spp., Listeria monocytogenes, Salmonella spp.,
Yersinia enterocolitica or Y. pseudotuberculosis, and verocytotoxigenic E. coli
(VTEC)/shigatoxin-producing E. coli (STEC)) being investigated in this study, but the
methods do not appear to have changed significantly over the last five years.
Report on the microbiological safety of fresh produce in New Zealand.
Escherichia coli (E. coli) is a normal inhabitant of the intestines and is necessary for nutrition and intestinal health. It is the most common facultative anaerobic bacterium in the faeces of warm-blooded animals and humans.
Report of a microbiological survey of foodborne pathogens in pre-packaged (bagged) fresh-cut ready-to-eat leafy salads.
Report of a microbiological survey of ready-to-eat, intact and fresh-cut vegetables and fruits.
Report on the microbiological quality of hydroponically grown vegetables from throughout New Zealand.
Following on from the PFGE report of isolates to the end of 2008 (PFGE Typing of Meat
Isolates of E. coli O157:H7 in New Zealand; ESR, March 2009), this report describes the
results of PFGE analysis of an additional 55 E. coli O157:H7 isolates from meat received by ESR to 1 October 2009, and includes nine isolates associated with the
AgResearch/AsureQuality “Investigating E. coli O157:H7 False Positives” project.
The data collected from these E. coli O157:H7 isolates contribute to a growing library of New Zealand PAGE profiles which facilitates future outbreak investigations and source attribution studies.
From March to September 2006, 25 isolates were uploaded to the PulseNet USA E. coli O157:H7 pulsed field gel electrophoresis (PFGE) database with the XbaI:BlnI pattern EXHX01.0074:EXHA26.0569. Although this pattern is relatively common in the US database, this number of isolates suggests a potential common source outbreak. USDA-FSIS found E. coli O157:H7 isolates from two meat-processing plants with two similar XbaI:BlnI patterns (EXHX01.0074:EXHA26.0569 and EXHX01.1401:EXHA26.0569). One common link between these meat-processing plants is that both sourced some of their meat from New Zealand.
The molecular typing by PFGE has now been completed on all E. coli O157:H7 isolates
from young calves, bovine, veal, prime beef, and human cases included in the 2006 PFGE
Emergency Response typing project as well as prime beef and veal isolates submitted to
ESR up to July 24th 2008. The PulseNet Aotearoa (New Zealand) E. coli database contains
723 NZ E. coli O157:H7 isolates, including 411 human, 189 meat, 118 animal, and 4
A survey of finished animal feed to determine the prevalence of several important zoonotic foodborne pathogens.
A new enrichment broth was introduced in the New Zealand red meat surveillance
programme for Escherichia coli O157:H7 in 2008. Modified TSB with novobiocin and
casamino acids (mTSB+NCA) replaced Modified EC (mEC) broth as the enrichment
media and the sample size to enrichment broth volume was changed from 125g per
1.125L to 375g per 1L.
An independent single laboratory study was performed by AsureQuality Auckland Laboratory to revalidate Escherichia coli O157:H7 screen kits following method amendments to the sample size and enrichment procedures in the New Zealand Food Safety Authority (NZFSA) E. coli O157:H7 monitoring programme for red meat.
A report to determine what scientific evidence was available to support sous vide cooking of meat, poultry, seafood, and eggs.
This document updates the 2007 Risk Profile considering STEC in raw milk. The purpose of this update is to critically review new information to answer the following risk management question: Has the public health risk from STEC in raw milk consumed in New Zealand changed since the 2007 Risk Profile?