ACMSF Minutes: 3 October 2013


Professor Sarah O’Brien

Dr Bob Adak
Dr Gary Barker
Mr John Bassett
Dr Roy Betts
Mrs Vivianne Buller
Mrs Rosie Glazebrook
Professor Rick Holliman
Ms Jenny Hopwood
Professor David McDowell
Dr Sally Millership
Mrs Jenny Morris
Mr David Nuttall

Departmental representatives:
Mr Stephen Wyllie (Defra)
Ms Liz Redmond (FSA)
Ms Ruth Parry (DH)

Dr Paul Cook (Scientific Secretary)
Ms Geraldine Hoad (Administrative Secretary)
Dr Sophie Rollinson
Mr Adekunle Adeoye
Miss Sarah Butler

Members of the Public:
Elizabeth Andoh-Kesson, British Retail Consortium
Katherine Domingo, Food Alert Ltd
Anita Drago, apetito Ltd
Kaarin Goodburn, Chilled Food Association
Angus Knight, Leatherhead Food International
Melanie Patterson, Life Technologies
Karen Sims, Waitrose
David Tompkins, WRAP
Elizabeth Williamson, Sainsburys
Nicola Wilson, Westward Labs

1. Chair’s introduction

1.1 The Chair welcomed ACMSF Members and members of the public to the Committee’s 81st meeting.

2. Apologies for absence

2.1 Apologies for absence were received from Professor John Coia, Mr Paul McMullin (who had provided written comments) and Mrs Joy Dobbs (SSRC ex-officio Member).

3. Declarations of interest

3.1 The Chair reminded Members of the need to declare any conflicts of interest relating to items on the agenda. The Chair declared an interest in relation to agenda item 8 as she had been involved in the Animal Health and Veterinary Laboratories Agency (AHVLA) risk assessment on abattoir inspection which was cited in the European Food Safety Authority (EFSA) scientific opinion on the public health hazards to be covered by inspection of meat (bovine animals). The Defra representative declared an interest in relation to agenda item 9 as he had been the official responsible for negotiating the EU rules on animal by-products which permitted use of animal waste in composts and digestates.

4. Minutes of the 80th meeting (ACM/MIN/80)

4.1 The Secretariat was asked to correct the final bullet on page 4 to clarify that Coxiella burnetii appears less infectious via the oral route, rather than more infectious. The Secretariat was also asked to amend page 6 paragraph 7.2 to say that “Livers were collected from final clearance flocks in slaughterhouses to increase the probability that they were contaminated with campylobacters.” Page 11 paragraph 9.2 was also amended to replace the word ‘disease’ with ‘organism’. Subject to these comments the minutes were accepted as an accurate record of the last meeting and the Secretariat was asked to publish them on the ACMSF website.
Action: Secretariat

5. Matters arising (ACM/1119)

5.1 Ms Hoad drew Members’ attention to the summary of actions taken on matters arising from previous meetings. All matters had been actioned.

6. Raw, rare and low temperature cooked foods (ACM/1120)

6.1 Dr Roy Betts was invited to present paper ACM/1120 reporting on the work of the Ad Hoc Group on Raw, Rare and Low Temperature Cooked Foods. Dr Betts explained that the group had met eight times over 15 months and reminded members of the terms of reference for the group and the scope of their work.

6.2 Dr Betts explained that there was no agreed definition of low temperature cooking and the group had therefore developed their own definition. He noted that FSA defines an adequate cook as application of 70°C for 2 minutes or an equivalent time/temperature to destroy pathogens. Equivalent processes for lower temperatures have been defined using standard calculations. For temperatures between 55°C and 59°C published information indicates that, if applied for a sufficient time, these temperatures should reduce any vegetative organisms present to safe levels but more data is needed to define safe cooking times between these temperatures. At temperatures below 55°C consideration needs to be given to growth of Clostridium perfringens as some data suggests it is able to grow at 52°C. Low temperature cooking raises several issues which could conflict with current regulations and advice such as the possibility that foods will be cooked at a lower temperature than that currently recommended for hot-holding of foods (63°C) and the possibility that meats could remain pink in the middle when safely cooked at low temperatures. These issues require some further consideration.

6.3 In relation to consumption of raw meats the group had considered that there would always be an associated increased microbiological risk but the foodborne illness outbreak data reviewed did not show any evidence of outbreaks associated with raw meat dishes in the UK. This could be due to the low volumes consumed and under-reporting of illness. Human illness due to inadequate cooking of meats had however been reported in UK outbreak data. In relation to meats served rare there were several processes that could increase the risk of internal contamination such as mincing of the meat. The cooking advice given in the 2007 ACMSF burgers report was considered by the group to still be relevant although the group also discussed the ‘sear and shave’ method for preparation of burgers and further work on this approach was recommended to fully understand the risks.

6.4 Dr Betts directed members to the groups’ recommendations in the paper and the Chair invited members to comment on:

  • the content and scope of the paper
  • the appropriateness and priority of the recommendations
  • the risks to consumers associated with use of low temperature cooking and foods of animal origin served raw or rare
  • the data gaps/research needs identified and the significance of these
  • any further work the Committee may wish to do on this topic or areas they may wish to explore in more detail e.g. fish/seafood, viruses, protozoa.

6.5 Members suggested that inclusion of a glossary would be a helpful addition to the paper. Some of the limitations around the ability of outbreak data to detect the impact of illness due to consumption of raw or rare foods (such as under-reporting of cases) were highlighted and it was suggested that these caveats could be clarified in the relevant section of the paper.

6.6 There was discussion on the perception that existed in some areas that using ‘higher quality’ meat meant there was less likely to be any microbiological contamination present. It was noted that some VTEC outbreaks linked to undercooked burgers are reported and these are often linked to ‘high end’ premises. It was suggested that there is a view amongst some food businesses that high value meat can be equated with ‘high quality’ and this is taken to mean that the product is safe, this view does not take account of the various points in the food chain where microbiological contamination can occur such as transport from the abattoir to the point of processing. Dr Betts clarified that the evidence examined by the group did not detail what was considered ‘high quality’ meat. Some members of the group were not comfortable with the ‘sear and shave’ technique suggested for burger production and suggested it was not practical for production of large volumes. The group recommended that this technique should be further investigated in terms of its ability to control the potential risks. Other Committee members did not share these concerns if the final product was treated as any other ready-to-eat food. It was noted that many burgers are made from meat trimmings rather than whole cuts of meat and these have a very different microbial profile and commercial value.

6.7 It was noted that when working with models to calculate z values at low temperatures, in addition to parameter uncertainty there would be model uncertainty as the models had not been validated for use at these lower temperatures. It was also suggested that at lower temperatures there were important considerations in terms of bacterial population dynamics. A Member agreed to draft some text on this point for the paper.

6.8 The Committee discussed risk assessment formats and their previous agreement to use a structured framework for risk assessments and why it was not used in this case. The Chair noted that when the group were given the brief for discussions on raw, rare and low temperature cooked foods the Committee may not have been clear about the type of output expected and whether the report would turn into a formal risk assessment or a discussion around the important issues. The direction of the draft document was now clearer but it was noted that it would be a significant amount of work to populate a formal risk assessment framework with this information. The Chair asked if the Committee wished a risk assessment to be carried out at this time. It was noted that in many instances there was insufficient data to populate a risk assessment. The discussions of the group had helped in clearly identifying where this data was lacking and could be considered a first step in the risk assessment process. It was agreed in this case not to populate a risk assessment framework.

6.9 In discussing the prioritisation of recommendations made in the paper Members agreed the priority should be further work on establishing and using z values for common organisms for low temperatures cooking. It was noted that these had already been established for E.coli in the burgers report. In terms of extending the considerations of the group to commodities other than meat it was agreed the Committee should take the learning and recommendations from this report and may revisit the issue of low temperature cooking of other foods, and the impacts of this form of cooking on other agents of food borne illness (such as protozoa), in the future.

6.10 The Chair summarised that members were content with the scope of the report and the data gaps identified and had prioritised further work on time temperature profiles for common organisms. The Chair asked for the amendments identified to be made to the paper and for the final version to be submitted to the FSA.
Action: Secretariat and Members

7. Update on viruses in the food chain (ACM/1121)

7.1 Prof Sarah O’Brien presented the draft report from the foodborne viral infections subgroup. Prof O’Brien clarified that the report was not intended as a full risk assessment but was an update on ‘state of the art’ with respect to foodborne viruses. The report was presented as a near final draft and a few sections were awaiting finalisation. As the report had been circulated to members at short notice it was noted that detailed comments were not expected, the intention of the discussion was to agree a process for finalising a draft for public consultation.

7.2 Prof O’Brien reminded members of the terms of reference for the group and outlined the main sections of the report and the data considered, this included the characteristics of the main viruses of concern (norovirus, Hepatitis E and A), detection of viruses in food, burden of disease, risk factors for infection, outbreak and surveillance data, investigation of foodborne virus outbreaks, contamination of foods via an infected handler and contamination of fresh produce and of shellfish. In relation to outbreaks it was highlighted that the groups understanding was that food businesses should alert their Local Authority as soon as they become aware of a potential outbreak of foodborne virus associated illness. However, it is not clear that this is always the case.

7.3 The report makes 44 recommendations and Prof O’Brien requested that Members provide their views on the priority of recommendations in relation to short, medium and long term priorities. Comments on the draft report were requested by 18th October. It was noted that comments would be incorporated into the report which would be subject to a public consultation. The aim was to issue the consultation in November and to have post-consultation draft at the January 2014 ACMSF meeting.

7.4 Members noted that the report represented a large and significant body of work and therefore it was important to consider it in more detail. It was noted that the terms of reference included agreement of a framework for outlining the key criteria for assessing the foodborne risks. Prof O’Brien agreed that that the report should be more explicit in saying that table 2 was important in that regard.
Action: Members and Secretariat

8. Mycobacterium bovis and the possible health risks associated with meat (ACM/1122)

8.1 Prof David McDowell chaired this item. Members were asked to review the risk classification for the human health risk associated with consumption of meat from animals with evidence of M. bovis infection. This had been considered by the Committee in 2012 and agreed as very low risk. The background to previous ACMSF risk assessments on this issue was summarised and the recent EFSA opinion on meat inspection (bovines), which classified the risk from M. bovis and meat as negligible, was referenced. It was noted that enhanced human surveillance for M. bovis in the UK has been maintained and there is a continuing absence of evidence of human infection from meat despite the increase in M. bovis in cattle.

8.2 Members queried whether meat, in the context of this risk assessment, included muscle and the other parts of the carcase. There was also discussion on the definitions of risk classification terms, the difference between very low and negligible and how consumers might perceive these terms. Members queried what difference it made in practice if the risk classification was changed from very low to negligible and whether this would lead to a relaxing of controls. The FSA departmental representative explained that changing the risk classification did not necessarily mean there would be any change in policy or existing controls. The current controls in the UK derived from EU-wide legislation, and the EFSA opinion would be used to inform an EC review on meat inspection procedures. The request to the Committee to review the classification was more an issue of risk communication and trying to be consistent in the way that risks were represented using the terminology agreed by ACMSF.

8.3 Members agreed that it would be worthwhile to restructure the assessment using the M. bovis and raw milk risk assessment framework and to document the associated uncertainties before the Committee reconsidered the risk classification. FSA requested the opportunity to seek the Committees’ view on the risk assessment question prior to undertaking any redrafting of the document and agreed to clarify the scope of the assessment with respect to meat and other organs.
Action: Secretariat

9. ACMSF response to WRAP’s revised compost and anaerobic digestate risk assessments (ACM/1123)

9.1 Dr Roy Betts introduced paper ACM/1123 reminding the Committee of their previous discussions and comments on WRAPs risk assessments. A subgroup of ACMSF members had met in September to consider the revised WRAP reports which incorporated changes in response to ACMSF’s previous comments and also to consider new work procured by WRAP as a result of ACMSF comments.

9.2 Dr Betts highlighted the main comments the group had made on the revised reports, these included:

  • Concerns on the over-precision in some of the risk estimates which implied a greater level of confidence in the results than was perhaps warranted.
  • A need for greater transparency on how the range of pathogens had been selected for inclusion in the assessment.
  • A lack of operational data on the rates of compliance achieved in practice. It was noted that some of the material may by-pass the pasteurisation step and the group were not confident in the data on the degree of by-pass and the level of compliance with the pasteurisation process. This remained one of the biggest areas of uncertainty due to the lack of data and the reliance on estimates.
  • Concerns over consumer acceptability on the use of meat and animal by-products as compost material.
  • New work had been procured by WRAP to address previous ACMSF concerns over Clostridium botulinum. The group found this work very helpful and it showed that there was no significant accumulation of C. botulinum spores in receiving soils following application of composts and digestates. However, with respect to C. botulinum toxins the group felt the results were equivocal and didn’t provide clear evidence that toxin(s) wasn’t produced during the anaerobic digestion process. WRAP had confirmed that a further study on this was being procured.
  • In general the group welcomed the changes made to reports and felt the additional work and amendments addressed most of the ACMSF’s previous comments. The group were generally satisfied that the microbiological risks arising from the production and use of PAS compliant composts were acceptably low, based on the evidence provided by WRAP to date and assuming full compliance with the statutory requirements.
  • It was not possible to come to a conclusion on the risks from C. botulinum types C and D as this would require consideration of the further work being procured by WRAP before a firm view could be reached.

9.3 The Chair thanked the group for looking at the reports and recognised this was a large undertaking given the length of the documents. Comments from Committee members were invited.

9.4 A Member of the WRAP subgroup noted that the risk to operators from spreading digestates and composts had been briefly considered by the group however, at the time of the discussions information on the recent respiratory tract infections in Scotland caused by Legionella longbechii, associated with compost was not available. The Defra representative queried whether the comments on by-pass related only to composts as digestates were a sealed system where by-pass should not be possible. Dr Betts noted that the comments applied to both systems as he understood that digestate could be fed into the system and come out again before it had undergone the full process, there was also a time requirement which if shortened could result in by-pass. There was some discussion on whether this constituted by-pass or non-compliance. It was noted that the group were concerned that it was not clear if non-compliance was rare or not and how it was enforced. Dr Betts concluded that the group were happy with the way the assessments had been carried out assuming full compliance with the required processes, however the level of compliance achieved was a risk management consideration which was outside the Committee’s remit.

9.3 The Committee agreed they were content with the subgroups comments and the Chair asked for these to be fed back to WRAP.
Action: Secretariat

10. Committee sub-groups

10.1 Dr Roy Betts reported that the ACMSF Surveillance Working Group had been asked to consider a preliminary report of an FSA microbiological survey of Listeria contamination of sliced meats in Small and Medium Enterprises (SMEs). Members had provided comments directly to the FSA and the full survey report was expected to be presented at the January ACMSF meeting.

10.2 Prof David McDowell updated the Committee on the first meeting of the Antimicrobial Resistance (AMR) Working Group. The Committee’s discussions were summarised in paper ACM/1124. Prof McDowell explained that the group had considered the outstanding recommendations from the ACMSF 1999 report on AMR. There were two main areas they felt had not been dealt with adequately. These were gaps in knowledge in relation to AMR in commensal organisms and the risks from imported foods. Prof McDowell explained that in addition to considering previously identified gaps in the evidence base the group would consider new gaps and gaps that had re-opened as a result of bacterial evolution.

10.3 In relation to commensal organisms it was noted that there had been a tendency to focus on pathogens with AMR genes. However resistance genes could pass from commensals to pathogens and vice versa and therefore there remained a need for an understanding of resistance in commensal organisms. It was noted that the means available for analysing and tracking AMR and the amount of data available on resistance genes had changed significantly in recent years and it was now possible to look at the epidemiology of a gene and track genes of interest. There was therefore a need to re-enforce the importance of this recommendation and the ability to now deal with it more effectively.

10.4 It was noted that the relative importance of imported foods in contributing to AMR remained unknown, but it was clear that conditions in different countries and application of different production systems resulted in different pressures on organisms which had a range of effects on AMR. There were also economic aspects that should be considered. The group considered this remained an area of concern where there were insufficient data and knowledge gaps that needed to be addressed. The group’s concerns extended to AMR in imported feedstuffs.

10.5 The group had also reviewed two recent European Medicines Agency (EMA) opinions on colistin and tigecycline antibiotics. They agreed with the EMA advice in relation to colistin and noted that tigecycline was not currently licensed for use in veterinary medicine and providing that this restriction remained, resistance should not pose a significant concern in UK produced food products.

10.6 The group reviewed a published paper which had attempted a quantitative assessment of human deaths and hospital admissions in European countries (including the UK) resulting from the presence of third generation cephalosporin-resistant E. coli in poultry. The paper had extrapolated information on the number of human infections with cephalosporin-resistant E. coli that could be associated with poultry consumption from the Netherlands and used this to derive an estimate in relation to UK deaths and hospitalisations. The group considered that the circumstances in the UK in terms of cephalosporin use were very different from the Netherlands and therefore the extrapolation was not justified as the surrounding uncertainties had not been made clear. However it was acknowledged that quantitative risk assessments were generally helpful in providing data to inform consideration of AMR issues.

11. Dates of future meetings (ACM/1125)

11.1 Members were asked to note the dates of the 2014 meetings on 30 January, 26 June and 2 October.

12. Any Other Business

12.1 The Chair explained that a letter had been sent to Committee Members notifying them of changes to senior posts in the FSA and the departure of the Chief Scientist, Andrew Wadge. In the interim, before appointment of a new Chief Scientific Advisor, challenge on science and science governance would be provided by the Chief Scientist’s support team and the Analytical Research Division.

12.2 A member suggested it may be interesting for the Committee to receive a presentation on the findings from the recently reported research on domestic kitchen practices at a future meeting.
Action: Secretariat

12.3 The ACMSF consumer members advised the Committee that she also sat on the FSA Consumer Advisory Panel (CAP) and it might be useful to include an update on the work of the CAP in the information paper on other advisory committees provided to ACMSF members at each meeting.
Action: Secretariat

Public Questions and Answers

13.1 The Chair drew formal proceedings to a close and invited questions and comments from the public in relation to ACMSF and risk assessment. There were no questions.