Advisory Committee on the Microbiological Safety of Food Ad
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ACM/1203a DRAFT Advisory Committee on the Microbiological Safety of Food Ad Hoc Group on Eggs An update on the microbiological risk from shell eggs and their products Advises the Food Standards Agency on the Microbiological Safety of Food 1 Ad Hoc ACMSF Group on eggs Membership: Prof John Coia (Chair) Dr Gary Barker Prof David McDowell David Nuttall Rosie Glazebrook Co-opted members: Prof Tom Humphrey, University of Swansea Rob Davies (Veterinary advisor and Salmonella consultant, APHA) Lesley Larkin (Veterinary advisor, APHA, and PHE epidemiologist from 2016) Chris Lane (PHE) Secretariat: Dr Manisha Upadhyay (Scientific Secretary) Sarah Butler FSA policy representative Narriman Looch 2 Terms of Reference The remit of the group is: - To assess the current level of microbiological risk to consumers (including vulnerable groups) from raw or lightly cooked shell eggs and their products. To assess how the risk with respect to Salmonella has changed since the last ACMSF report on this subject in 2001. The working group will report back regularly to the ACMSF. Scope: All commercially1 available edible shell eggs and liquid and frozen eggs including those on retail sale and from catering establishments. Shell eggs and liquid and frozen eggs produced in the UK (those from quality assurance schemes and others) Shell eggs and liquid and frozen eggs produced in the EU and those imported from third countries. Outputs: The working group will prepare an assessment of the current microbiological risk from shell eggs and liquid and frozen eggs and will also indicate whether the risk associated with Salmonella has changed since the ACMSF 2001 report. The working group will prepare a report on its findings concerning the current level of risk from shell eggs and liquid and frozen eggs and make a recommendation(s) on whether the Agency’s existing guidance on shell eggs remains appropriate. Any other relevant recommendations can be included in this report. The working group will present its report to the main ACMSF Committee for endorsement. 1 Regulation 852/2004 provides the following exemption: “the direct supply, by the producer, of small quantities of primary products to the final consumer or to local retail establishments directly supplying the final consumer” In order for this exemption to apply, the quantities involved must be small and the supply must be direct to the final consumer. Under an exemption in EU Egg Marketing Regulations, eggs in shell may be sold directly to the final consumer without any quality or weight grading. Furthermore, the direct supply of small quantities of eggs to the final consumer is also exempt from complying with the food hygiene regulations. FSA guidance suggests up to 360 eggs a week is a small quantity. 3 Contents Overall risk assessment and key recommendation Chapter 1: Introduction Background to the review 1.1 – 1.6 Salmonella Enteritidis contamination of eggs 1.7 – 1.10 A summary of the prevalence of Salmonella Enteritidis in chickens 1.11 – 1.25 and humans Changes from 2001 to present 1.26 – 1.28 Non-UK eggs 1.29 – 1.32 Egg surveys 1.33 – 1.47 Duck eggs and other eggs 1.48 – 1.49 Foodborne outbreaks linked to eggs and egg products 1.54 – 1.58 General outbreaks of foodborne disease in England and Wales 1.59 – 1.69 2009 – 2014 linked to eggs and/or egg products Foodborne disease outbreaks in England and Wales linked to egg 1.70 – 1.73 products Conclusions 1.74 – 1.86 Recommendations 1.87 – 1.91 Chapter 2: Identification of microbiological hazards associated with eggs and egg products Overview 2.1 – 2.5 Horizontal transmission leading to internal contamination of eggs 2.6 – 2.12 Background on the public health risk associated with Salmonella 2.13 – 2.16 in eggs and egg products Salmonella Enteritidis 2.17 Mechanisms of contamination of eggs with Salmonella Enteritidis 2.18 Vertical transmission of Salmonella Enteritidis 2.19 – 2.22 Horizontal transmission leading to internal contamination of eggs 2.23 with Salmonella Enteritidis Other possible egg-associated bacterial pathogens 2.24 – 2.34 Eggs from other species 2.35 – 2.40 4 Relevance of backyard chicken production 2.41 – 2.44 Microbial contamination of egg products 2.45 – 2.51 Conclusions 2.52 – 2.61 Recommendations Chapter 3: Egg industry in the UK. Consumption patterns relating to different egg types and products UK egg consumption (hens’ eggs) 3.1 – 3.2 UK egg production systems 3.3 – 3.5 Egg products 3.6 – 3.7 Consumption of eggs other than hens’ eggs in the UK Duck eggs 3.8 Quails’ eggs 3.9 Internet sales 3.10 Conclusions 3.11 – 3.17 Recommmendation 3.18 Chapter 4: Storage, handling and use of eggs Introduction 4.1 Egg production and consumption 4.2 Food safety concerns 4.3 – 4.11 Domestic use of eggs 4.12 – 4.16 Recent changes 4.17 Non-UK eggs 4.18 - 4.20 Eggs and egg products online 4.21 Small holding/backyard egg production 4.22 – 4.25 Conclusions 4.26 – 4.30 Recommendations 4.31 – 4.37 Chapter 5: Description of interventions relating to laying hens, chickens, ducks, quails and any other (a) Interventions to control Salmonella in egg production 5.1 – 5.21 Salmonella National Control programmes at primary production 5.22 – 5.29 Research on control of Salmonella in the duck egg industry 5.30 – 5.34 5 Conclusions 5.35 – 5.39 (b) Other interventions 5.40 Provision of Guidance Guidance to Food Business Operators 5.41 Guidance to Consumers 5.42 Other statutory requirements 5.43 – 5.48 Recommendation 5.50 (c) Scientific robustness of anti-Salmonella interventions Background 5.51 – 5.53 Production Control measures 5.54 Vaccination 5.55 – 5.61 Salmonella Enteritidis evolution 5.62 Uncertainty 5.63 – 5.65 Under-reporting of human Salmonella cases 5.66 – 5.69 Effect of temperature and duration of storage on the growth of 5.70 – 5.71 Salmonella within eggs Detection of Salmonella in eggs 5.72 – 5.80 Factors influencing detection of Salmonella infected flocks: Detection methods 5.81 – 5.82 Sensitivity model and within flock prevalence 5.83 – 5.85 The impact of housing and production systems 5.87 – 5.92 Environmental contamination 5.93 – 5.94 The role of non-UK eggs in Salmonella Enteritidis 5.95 – 5.100 infections/outbreaks in the UK Conclusions 5.101 – 5.110 Chapter 6: Revisiting the risk assessment model. Have all the data gaps identified in 2001 been filled? The FSA risk assessment model 6.1- 6.16 Additional considerations 6.17- 6.18 Other risk assessment models 6.19 - 6.22 Recommendation 6.23 6 Chapter 7: Role of different Salmonella Serovars in egg contamination Background 7.1- 7.11 Salmonella Enteritidis has a higher ability to infective reproductive 7.12 – 7.19 hen tissues and contaminate egg contents Conclusions 7.20 – 7.24 Recommendation 7.25 Chapter 8: Importance of surveillance and identification of emerging threats Surveillance considerations 8.1- 8.7 Molecular Epidemiology 8.8 – 8.11 Conclusions 8.12 – 8.13 Chapter 9: Recommendations Annex I: Recommendations from previous ACMSF Report Annex II: Details on surveys of Salmonella contamination in table eggs Annex III: Legislation Glossary References 7 Overall risk assessment and key recommendation The ACMSF Ad hoc Working Group on eggs was asked to assess the current level of microbiological risk to consumers (including vulnerable groups) from raw or lightly cooked shell eggs and their products, and specifically to assess how the risk with respect to Salmonella has changed since the last ACMSF report on this subject in 2001. The Group concluded that with respect to hen shell eggs, whilst a range of micro- organisms could potentially contaminate the shell surface and possibly the egg contents, the only group of organisms of significant importance in respect of contents contamination is Salmonella. This latter risk is generally limited to a subset of these bacteria, principally Salmonella Enteritidis. It was the strong view of the Working Group that there has been a major reduction in the microbiological risk from Salmonella in UK hen shell eggs since the 2001 ACMSF report. This is especially the case for those eggs produced under the Lion Code, which comprises a suite of measures including: vaccination, a cool chain from farm to retail outlets, enhanced testing for Salmonella, improved farm hygiene, better rodent control, independent auditing, date stamping on the eggs and traceability. The risk from imported eggs has also been reduced but not to the same extent. Accordingly, the group suggests that the risk level for UK hen shell eggs produced under the Lion code, or produced under demonstrably-equivalent comprehensive schemes, should be ‘VERY LOW’, whilst for other shell eggs the risk level should be considered ‘LOW’. In practical terms, the Group considered that the ‘VERY LOW’ risk level means that eggs produced under the Lion code, or produced under demonstrably equivalent comprehensive schemes, can be served raw or lightly cooked to all groups in society, including those that are more vulnerable to infection, in both domestic and commercial settings, including care homes and hospitals. The Group considered that for those eggs in the ‘LOW’ risk group (UK produced non-Lion code hen shell eggs, and non-UK hen shell eggs) that the existing advice should remain i.e. that the very young, the elderly, pregnant women, and those who are already unwell, should not consume these eggs raw or lightly cooked. Similarly, we also consider that existing advice should remain for non-hen shell eggs. Consumers and caterers must continue to be aware of the need to store eggs properly, to observe use by dates, and to avoid cross-contamination of eggs within the kitchen environment, particularly where the eggs’ contents will be consumed raw or lightly cooked.