Other microbiological food safety research

The purpose of a Risk Profile is to provide contextual and background information relevant to a food/hazard combination so that risk managers can make decisions and, if necessary, take further action. Risk Profiles include elements of a qualitative risk assessment, as well as providing information relevant to risk management. Risk profiling may result in a range of activities e.g. immediate risk management action, a decision to conduct a quantitative risk assessment, or a programme to gather more data, ranking of a particular food safety issue.

Bacillus cereus is a spore-forming bacterium that occurs naturally in many kinds of foods and can cause illness in humans. It can form spores that are resistant to heating and dehydration and can therefore survive cooking and dry storage.

This Risk Profile (RP) considers Bacillus cereus in dairy products intended to be consumed as whole foods, including milk (raw, processed, concentrated, powder), cream, butter, yoghurt, cheese, ice cream and foods where dairy is the main ingredient (e.g. custard). The purpose of the RP is to critically review available information to answer risk management questions related to the ways of contamination and levels and behaviour of B.cereus in dairy products.

The purpose of a Risk Profile is to provide information relevant to a food/hazard combination
so that risk managers can make decisions and, if necessary, take further action. Risk Profiles
include elements of a qualitative risk assessment, as well as providing information relevant to
risk management.

This report defines the baseline of levels of contamination of sulphite-reducing clostridia (SRC) in New Zealand nutritional dairy powders. It also evaluates whether or not routine testing of dairy powders for SRCs in New Zealand, and setting of microbiological criteria, are required for regulatory assurances.

The Clostridium botulinum types involved in infant botulism belong to Group I and produce
type A, B and to a lesser extent type F toxins. When spores of the organism are ingested by
infants (who have an incomplete intestinal microflora) they may become established and
grow.

Clostridium botulinum and related organisms are anaerobic bacteria that can grow in food and produce an extremely potent neurotoxin (BoNT) causing a food poisoning syndrome known as botulism. Internationally BoNT-producing organisms are of particular concern to seafood producers because one group of these organisms (Type E) naturally occurs in the marine environment and can grow and produce toxins at refrigerated temperatures. The aim of this research was to determine the prevalence of BoNT-producing organisms in the New Zealand marine environment.

The Ministry for Primary Industries (MPI) commissioned a review of the scientific literature on high pressure processing (HPP) to address validation expectations for HPP as a control measure for the inactivation of food borne bacterial pathogens. The review collates information from the scientific literature, outlines the impact of product and process variables on pathogen inactivation by HPP, and provides direction on how these should be addressed during validation work.

A report to determine what scientific evidence was available to support sous vide cooking of meat, poultry, seafood, and eggs.

This report describes the results of a microbiological survey to determine compliance with E. coli, Salmonella, and CPS microbiological limits as specified in the Food Standards Code.

The purpose of this Risk Profile is to critically review available information and determine if the risk to human health from V. parahaemolyticus had changed since 2003.
Keywords: Risk Profile, Vibrio, parahaemolyticus, bivalve, molluscan, shellfish

The purpose of this Risk Profile is to critically review available information and determine the risk to human health from V. vulfificus in bivalve molluscan shellfish.

Keywords: Risk Profile, Vibrio, vulfificus, bivalve, molluscan, shellfish

An infrequent cause of disease in New Zealand, but has a high associated case fatality rate. It is a marine organism (grows in 6% NaCl) that can grow both in the presence and absence of air.

A marine Vibrio normally associated with food poisonings involving seafood consumption. It is a major cause of food poisoning in Asian countries. Certain strains (Kanagawa phenomenon-positive, KP+) are primarily involved with human disease.

NZFSA commissioned Cawthron Research Institute to conduct a microbiological survey to determine the levels of total and pathogenic Vibrio parahaemolyticus (Vp) and Vibrio vulnificus (Vv) in Pacific oysters (Crassostrea gigas) collected from commercial growing areas in the North Island of New Zealand.

The species is divided into serotypes on the basis of the O antigen. Cholera is typically associated with O1, but serotype O139 has also been the cause of many cases of cholera in Asia.

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.

In the five year period (2002 to 2006) reviewed, the annual notification rate for yersiniosis in New Zealand increased over the four years 2003 to 2006 but remained lower than it was in 2002. A number of District Health Boards (DHBs) (West Coast, South Canterbury, Capital and Coast) had consistently higher notification rates than the overall New Zealand notification rate. Children aged less than 5 years experienced the highest rates of yersiniosis and there was a small increase in the notification rate for the 60 years and over age group.

In New Zealand, cases of human illness and laboratory detection of either organism are notified to ESR and Y. enterocolitica is more commonly reported than Y. pseudotuberculosis. A seasonal pattern is apparent from the data, with more cases reported in the months of October, November and January (Pirie, 2008). A large proportion of cases are believed to be attributable to food. This datasheet focuses on Y. enterocolitica.

The purpose of a Risk Profile is to provide contextual and background information relevant to a food/hazard combination so that risk managers can make decisions and, if necessary, take further action. Risk Profiles include elements of a qualitative risk assessment, as well as providing information relevant to risk management. Risk profiling may result in a range of activities e.g. immediate risk management action, a decision to conduct a quantitative risk assessment, or a programme to gather more data, ranking of a particular food safety issue.

Toxoplasma gondii is an obligate intracellular parasite that occasionally causes serious illness in immunocompromised individuals and unborn babies. It is estimated that one third of all humans have been exposed to T. gondii, but most instances of toxoplasmosis are mild or asymptomatic.

Growth and toxin production is best in the presence of oxygen but can grow anaerobically. It is not regarded as a good competitor with other bacteria. Infected food handlers are a significant cause of food poisonings.

This genus includes four species; S. dysenteriae, S. flexneri, S. boydii and S. sonnei, which are able to cause bacillary dysentery. They are very similar to Escherichia coli and are serologically cross reactive, but have remained separate species for clinical reasons.

Cryptosporidium parvum and Cryptosporidium hominis are intracellular protozoan parasites that may produce gastrointestinal symptoms when ingested by humans. Up until 2002, C. parvum was named C. parvum genotype 2 (cattle genotype) and C. hominis was named C. parvum genotype 1 (the human genotype). They are now recognised as different species based on genetic distinctions.

The purpose of a Risk Profile is to provide contextual and background information relevant to a food/hazard combination so that risk managers can make decisions and, if necessary, take further action. Risk Profiles include elements of a qualitative risk assessment, as well as providing information relevant to risk management. Risk profiling may result in a range of activities e.g. immediate risk management action, a decision to conduct a quantitative risk assessment, or a programme to gather more data, ranking of a particular food safety issue.

There are two pathogenic species of the Cryptosporidium parasite that infect humans; C.
parvum and C. hominis. C. parvum can also infect bovines. When excreted by the host, the
environmental form of Cryptosporidium is the oocyst, which contains four sporozoites, and is
a very resilient organism that can withstand many environmental stresses including
chlorination.

This paper is part of the New Zealand Food Safety Authority’s scientific evaluation of foodborne hazards. The focus is the bacterium Mycobacterium avium subspecies paratuberculosis (MAP), which has been reported as a possible food contaminant, particularly in dairy products.

This is one of two species of the “tubercle bacilli” (the other is M. tuberculosis) that are able to cause tuberculosis. Unlike M. tuberculosis, M. bovis infects cattle and other animals, and so the disease can be spread to humans via contaminated milk and
meat.

Enterobacter sakazakii was recently reclassified into eight distinct taxa of a new genus Cronobacter (Iversen et al., 2008). All have been linked retrospectively to clinical cases in adults and infants (FAO/WHO, 2008). To avoid confusion the organism will be referred to here as Cronobacter spp.

Arcobacter is a member of the Epsilobacteria group, which also includes Campylobacter and Helicobacter spp. It is distinguished from Campylobacter by being able to grow in the presence of oxygen (aerotolerant) and at 15ºC.

The purpose of a Risk Profile is to provide contextual and background information relevant to a food/hazard combination so that risk managers can make decisions and, if necessary, take further action. Risk Profiles include elements of a qualitative risk assessment, as well as providing information relevant to risk management. Risk profiling may result in a range of activities e.g. immediate risk management action, a decision to conduct a quantitative risk assessment, or a programme to gather more data. Risk Profiles also provide information for ranking of food safety issues.

Toxoplasma gondii is a protozoan parasite that infects warm blooded animals.

MPI Technical Paper No. 2015/33. This Risk Profile considers Toxoplasma gondii in red meat and meat products. This is an update of a Risk Profile “Toxoplasma gondii in red meat and meat products” published in 2008 (Lake et al., 2008).

Twenty three of the thirty establishments visited can readily meet the presentation requirements and accept the need for the changes.

The study evaluated the impacts of alternative post mortem inspection regimes for tuberculosis in cattle presented for slaughter in New Zealand relative to current practices. A retrospective analysis of slaughterhouse post mortem data collected from M. bovis infected animals was conducted and then a model which accurately simulated the current observed lesion prevalence was developed. It was found that approximately 50% of tissues could be dropped from the examination with only a 2% loss of sensitivity. A group of “operationally relevant” tissues could be dropped with only a 1% loss of sensitivity.

keywords: Bovine tuberculosis, lymph nodes, post mortem examination

The production of sheep and lamb meat is a significant part of the economy of New Zealand. Technological advances over many years have enhanced the efficiency, productivity and hygiene of sheep meat production, none more so than the introduction of inverted dressing (Longdell, 1992) where the de-pelting operation starts at the cleaner end of the carcass, and the pelt is moved downwards towards the rear, more contaminated, end.

This document describes a scientific evaluation of the likely contribution of routine post
mortem examination of selected lymph nodes of cattle slaughtered in New Zealand to
food safety and to food suitability. Currently all carcass lymph nodes are required to be
examined by intensive examination while the mesenteric lymph nodes are examined by
viewing and palpation. In addition to questions over food safety aspects, there is scientific consensus that intensive routine examination of lymph nodes is likely to increase crosscontamination of some tissues.

The current bovine post mortem procedures in New Zealand for the examination of the gall bladder, pericardium, penis and reticulum were scientifically evaluated as to their contribution to food safety. A risk profiling approach demonstrated that the following changes to current procedures would not affect food safety outcomes: no examination of the gall bladder, examination of the pericardium included within viewing of the heart, examination of the penis when saved as for human consumption by viewing and examination of the reticulum by viewing during examination of the gastro-intestinal tract.

The Meat Industry Association stated in its 2005 presentation to the NZFSA Verification Agency that one of the strategic goals of the meat Industry in Towards 2006 is…..” To be at the forefront of international food safety.” This goal is thoroughly supported by NZFSA and is unarguably an approach that will assist New Zealand in maintaining its deserved reputation as the world’s largest exporter of sheep-meat of the highest quality

This project describes a scientific evaluation of the likely contribution of routine post mortem examination of tissues of the bovine carcass and viscera.

New Zealand produces a range of ready-to-eat dried meat products where food safety often relies on a cook or fermentation step. However, some dried products use water activity, pH or added ingredients to ensure food safety. There is little documented proof to support validation of the food safety aspects of the drying process. This review determines if any existing models can be used to validate this process and provide guidance or a predictive model for the inactivation of pathogens of concern.

Update of a report made in 2011, with surveillance data for the 2013 year and updated estimates.

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.

Evaluation of viable but not culturable (VNC) state of various foodborne pathogens.

Expert elicitation-derived estimates of foodborne proportions of enteric illnesses