Campylobacter research
Primary production
NZFSA set up a caecal sampling programme under the Campylobacter in Poultry Risk Management Strategy 2006-2009 to provide an initial baseline survey of the prevalence of Campylobacter in all New Zealand broiler flocks at each cut. The programme also was expected to provide information to assist with 1) risk management decisions and 2) the NZ risk model for Campylobacter in broiler chicken. Sampling has been occurring for two years.
Final Report on a Contract Research Project Conducted by Massey University for NZ Food Safety Authority - March 2011
This report is part of a project investigating on-farm risk factors for Campylobacter contamination of poultry flocks in New Zealand. It is intended to contribute to the identification of such factors that offer opportunities for risk management. The preparation of this report will be followed by farm visits during early 2007.
This report describes the results from a survey of broiler farms in New Zealand intended to capture detailed information relevant to biosecurity practices. A total of 60 of the approximately 160 broiler farms in New Zealand were visited.
A survey of finished animal feed to determine the prevalence of several important zoonotic foodborne pathogens.
NZFSA commissioned a science project by ESR to indicate whether overall garments worn by farmers entering sheds housing Campylobacter positive broiler chicken flocks could be
contaminated with the pathogen. A further aspect of the study was to determine if debris shaken loose from overalls could transfer infection to other sheds.
The Science Group of NZFSA commissioned ESR to investigate on-farm factors in New
Zealand that potentially affect the infection of broilers with Campylobacter. The resulting
report contained an international literature review as well as an overview of broiler farming in
New Zealand.
Processing
Campylobacteriosis is the most frequently reported bacterial foodborne illness in New Zealand and a major route of infection with Campylobacter spp. is contaminated food consumption. A recent attribution study conducted in the Manawatu district of New Zealand has identified poultry meat as a primary exposure pathway of campylobacteriosis (Mullner et al., 2009).
The poultry industry and supermarkets in New Zealand have recently introduced leak-proof packaging for retail sale of whole birds and a proportion of packs of portions. This is intended to eliminate the risk of leaking drip fluid from these products contaminating the retail environment, and provided the products are properly handled by consumers, provides the potential for preventing cross contamination in the home. This study had the aim of providing basic data on the amount of drip retained within this type of packaging, and the numbers of Campylobacter spp. in the liquid.
- Scientific interpretive summary - Chlorine and poultry [DOCX, 14 KB]
Chlorine has a long history of use for the microbial disinfection of potable waters and use in
water for food processing. However, in addition to its biocidal activity, chlorine is known to
form disinfection by-products (DBPs) of public health concern during the chlorination
process.
The Ministry for Primary Industries (MPI) has a current regulatory Campylobacter testing programme within the National Microbiological Database (NMD) for poultry (currently defined as broiler chicken) which provides information for MPI and the poultry industry. In particular, the Campylobacter testing programme:
Prepared for New Zealand Food Safety Authority under project mfsc/08/03/06 “Longitudinal mapping of Campylobacter on poultry carcasses” as part of overall contract for scientific services by Dr Susan Paulin Institute of Environmental Science & Research Limited. January 2011
Since April 2007, a testing programme has been in place at New Zealand poultry primary
processing plants to determine the Campylobacter spp. status of birds entering primary
processing, and carcasses at the end of processing. The end of processing testing includes
rinsing of carcasses taken after the immersion chiller, plating of a rinse subsample, and
counting of Campylobacter colonies, if present.
The aim of this work was to determine how the numbers of Campylobacter, quantified by the NMD sampling procedure, related to actual bacterial counts present on the carcass of birds obtained from four New Zealand poultry processors. Birds were collected at positions on the production line that were likely to optimise the chances of obtaining quantifiable numbers of Campylobacter from rinsates and macerated and/or homogenised skin samples.
The Ministry of Agriculture and Forestry (MAF) now incorporates the New Zealand Food
Safety Authority (NZFSA). MAF invites public comment on this discussion document which
outlines proposals to amend the Animal Products (National Microbiological Database
Specifications) Notice 2011 including parts of Schedule 1.
This study was conducted in order to quantify the distribution of Campylobacter on various sites of the poultry carcass, and to determine whether any differences existed in the relative distribution of Campylobacter on chicken between two New Zealand poultry processors (defined as Processor A and Processor B).
The Ministry for Primary Industries (MPI) has a current E.coli and Campylobacter testing
programme for meat chickens which provides information to:
• Verify the effectiveness of the industry’s control measures for these organisms during
slaughter and dressing,
• Enable MPI to explore whether these control measures impact on human food-borne
illness rates, and
• Identify and review risk management options under MPI’s relevant pathogen
strategies.
Describes the risk of foodborne illness in New Zealand associated with Campylobacter Jejuni/Coli in Poultry (Whole and Pieces)
This risk profile concerns Campylobacter in offal (liver and kidney). In New Zealand, the prevalence of Campylobacter in offal in general is high. External contamination of poultry livers in one study was 100%, while internal contamination was 90%. Sheep liver has a contamination prevalence of approximately 38.9% to 66.9%. Bovine and porcine offals appear to be less commonly contaminated (<10%).
In recent times New Zealand has experienced high human campylobacteriosis notification rates. A Campylobacter Risk Management Strategy was put in place in 2006 to reduce this high disease burden.
Since April 2007, a testing programme has been in place at New Zealand’s poultry primary processing plants to determine the Campylobacter spp. status of carcasses at the end of processing. This testing includes rinsing of carcasses taken after the immersion chiller, plating of a rinse subsample, and counting of Campylobacter colonies, if present.
This survey was undertaken to improve NZFSA’s understanding of the effectiveness of rinsates to remove Campylobacter from poultry carcasses. The rinsate method described in the National Microbiological Database (NMD) was of particular interest.
Consumers
Literature review of evidence around the aetiology of human campylobacteriosis in New Zealand, including evidence around foodbourne transmission.
The Acute Gastrointestinal Illness (AGI) Study is a set of three linked surveys, with the
following objectives:
• To determine the magnitude and distribution of self reported AGI in the New Zealand
population;
• To estimate the burden of disease associated with AGI;
• To describe and estimate the magnitude of under-ascertainment of AGI at each stage
in the national communicable disease surveillance process; and,
• To identify modifiable factors affecting under-ascertainment that, if altered, could
reduce case loss throughout the AGI component of the surveillance system.
This report describes the work conducted by ESR on the project “Campylobacter in food and the environment: Examining the link with public health”. The project, which began in July 2007, is a collaboration between ESR and scientists at the Ministry of Agriculture and Forestry (MAF), Ministry for the Environment (MfE), the National Institute for Water and Atmospheric Science (NIWA) and Massey University. It is funded through the Foundation for Research, Science and Technology (FRST) under the Cross Departmental Research Pool (CDRP) portfolio.
One hundred and seventy-five samples of diced or minced retail chicken meat were tested
for the prevalence and concentration of Campylobacter spp. to measure the impact of
introducing the mandatory Campylobacter performance target (CPT) to primary broiler
chicken processing on Campylobacter spp. levels in retail uncooked chicken meats. Samples were obtained from retail outlets in Auckland, Hamilton, Wellington, Christchurch and Dunedin using the protocol of the 2003–2004 survey. Data generated on the prevalence and concentration of Campylobacter spp. in the chicken meat samples were compared with those from the survey conducted in 2003–2004.
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.
A significant proportion of foodborne illness is thought to be caused by unsafe food handling practices in the home. Data on the food handling practices of New Zealanders is limited. This project was initiated to provide more, and better targeted information on domestic handling of meat and poultry in New Zealand. The information is needed to support risk assessment by the New Zealand Food Safety Authority, particularly the development of quantitative risk models to assess potential interventions.
Campylobacteriosis is the most frequently reported gastrointestinal illness in New Zealand, with greater than 50% of cases being attributed to consumption of chicken (Eberhart-Phillips et al., 1997). A recent commentary by Baker and colleagues (2006) on the rates of Campylobacter infection in New Zealand has suggested that all fresh poultry should be temporarily withdrawn from the food supply and replaced with frozen or processed alternatives.
The main objective of this work was to identify means that could be employed to minimise
risk and reduce the burden of campylobacteriosis in the New Zealand population by reducing the numbers of Campylobacter on fresh poultry meat. An assessment was to be made of the effectiveness of temperature controls by freezing or chilling in the reduction of
Campylobacter numbers achieved under standard industry practice, and under potential new chilling regimes.
Recent NZFSA-funded studies showed a strong correlation between Campylobacter jejuni
populations isolated from fresh broiler chickens and those isolated from human clinical
cases in New Zealand. This work was conducted between March 2005 and Feb 2008 in the Manawatu, Christchurch and Auckland, and supported previous studies indicating that broiler chickens were the primary food source responsible for human campylobacteriosis in this country. This led to the national control policy targeting broiler poultry in New Zealand.
Source attribution of human campylobacteriosis in a sentinel area (Manawatu).
The NZFSA Science Group contracted ESR to conduct experiments on the effect of freezing,
storage and thawing on survivability of Campylobacter jejuni under simulated domestic and
commercial conditions. The experiments used skin-on product as the scientific literature has
indicated that the impact of freezing, storage and thawing on Campylobacter on skin-off
product is likely to be less.
Report of a microbiological survey of foodborne pathogens in pre-packaged (bagged) fresh-cut ready-to-eat leafy salads.
Report on the microbiological quality of hydroponically grown vegetables from throughout New Zealand.
This project was initiated to quantify the reduction of two Campylobacter jejuni strains,
STu48 and ST474, following commercial freezing (-30°C), commercial frozen storage (-
21°C) for two weeks and domestic storage (-18°C) for a further eight weeks. Significant but
variable reductions in C. jejuni numbers were observed over time for both strains, with
reductions most rapid during the 14 days of commercial frozen storage.
Domestic food practices in New Zealand:
Quantifying the reduction of Campylobacter Jejuni on skin-on chicken breasts frozen and stored for up to 10 weeks at -12°C
A report to determine what scientific evidence was available to support sous vide cooking of meat, poultry, seafood, and eggs.
Sources
An examination of the suitability of various source attribtion models, taking account of temporal variation, of campylobacteriosis.
Results of multilocus sequence typing and source attribution modelling of campylobacterisolates in the Manawatu culture bank 2009–10.
The molecular epidemiology of human campylobacteriosis was studied in the Manawatu (Quantifying the proportion of human campylobacteriosis attributable to consumption of poultry meat in New Zealand: a Manawatu case study).
This report provides an update of the relative contribution of different reservoirs to the burden of human campylobacteriosis in the Manawatu sentinel site. It summarises the results of multilocus sequence typing of isolates stored in the culture bank of Campylobacter jejuni samples from poultry and humans in the Manawatu sentinel site, and the epidemiological data linked to the human cases.
This report proportionally attributes human cases of campylobacteriosis to reservoir sources in the Manawatu over the period January to December 2015. Modelling attributed ~50% (45–70%) of the human cases to poultry and 37% (25–50%) to ruminants, predominantly cattle. Urban cases are more associated with poultry strains and rural with ruminant. These proportions refer only to the animal reservoirs associated with strains and do not examine the pathway of exposure to Campylobacter, e.g. direct animal contact, meat from the reservoir animal, other foods, drinking or recreational, water, etc. While the predominant poultry strain (accounting for 31% of isolates) was the antimicrobial-resistant sequence type ST-6964, it was detected from only four human cases and still does not appear to present additional risks to public health.
This report provides an overview of campylobacteriosis in New Zealand and describes some of the work undertaken to inform decision making.
Other
This organism causes the most commonly reported gastrointestinal disease in New Zealand. The two species Campylobacter jejuni and C. coli are most often associated with disease. It grows best in reduced oxygen atmospheres and only at temperatures
exceeding room temperature.
NZFSA’s Campylobacter risk Management Strategy is progressing well, with only a few areas threatening to affect the timetable. This update covers the work that is being done on possible effective interventions at all steps along the farm-to-fork food chain. NZFSA’s approach is in line with that being taken internationally to address the problem of the presence of Campylobacter in poultry, and aims to produce the greatest reductions in bacteria numbers as early as possible in the food chain (that is, as close to the farm as is practical and effective), as well as make further reductions at as many other points as are also practical and effective.
The Ministry for Primary Industries (MPI), is the government organisation responsible for
New Zealand’s Food Safety System. The New Zealand Food Safety System extends from
‘farm to fork’, allowing consumers in New Zealand and around the world to buy and consume our products with confidence that they are safe and suitable.
The Campylobacter Risk Management Strategy 2017-2020 sets out MPI’s goal, approach and objectives.
This report describes the development of a quantitative risk model to investigate Campylobacter spp. contamination in the processing and consumption stages of the New Zealand poultry food chain. It covers work during the period 2003-2006.
Evaluation of viable but not culturable (VNC) state of various foodborne pathogens.
Evidence from disease notifications, case investigations, outbreak investigations and epidemiological studies of human enteric diseases is increasingly used as a source of data for risk assessments and source attribution. However, its application is often restricted by the strength of the evidence presented and its interpretation. Geographical variations in disease incidence have long been described in New Zealand but their aetiologies have not been identified. A range of reports have described variation in the present system of public health investigation and the management of identified cases of human enteric diseases.
For regulators to make the best use of food safety resources, they need to identify, assess and compare the risks posed by various contaminant/food combinations and prioritise opportunities for reducing risks through targeted food control initiatives. Reliable estimates of both the incidence of foodborne illness and its financial impact are essential for informing policy decisions in food safety. The previous (2005) New Zealand estimates of the cost of foodborne disease had a number of uncertainties and data limitations.
A scientific project was commissioned to determine whether New Zealand strains of foodborne pathogens can enter the VNC state.
Report prepared for NZ Food Safety authority, November 2010, concerning the economic cost of campylobacteriosis, salmonellosis, norovirus, yersiniosis, STEC, listeriosis
This risk profile was commissioned to address the following risk management questions:
• What are the potential public health and food safety risks associated with the
emergence of Campylobacter ST 6964 in New Zealand?
• What are the significant data gaps which, if filled, would allow a more comprehensive
assessment of public health risks attributable to the emergence of Campylobacter ST
6964 and its associated antimicrobial resistance in New Zealand?
A report summarising transmission routes for campylobacteriosis in New Zealand (food and environmental).