ACMSF minutes: 22 September 2005

To be held in Aviation House, 125 Kingsway, London WC2B 6NH.

Present

Chairman:
Professor B Reilly

Members:
Mr J Bassett
Dr D Brown
Mrs V Buller
Ms S Davies
Professor M Gasson
Dr K Hadley
Professor T Humphrey
Professor P Hunter
Mr A Kyriakides
Ms E Lewis
Mr P McMullin
Mr P Mepham
Professor S O'Brien
Professor L Piddock
Mr R Rees
Professor P Williams

Assessors:
Mr P Gayford (Defra)
Dr J Hilton (FSA)
Dr S Neil (DARDNI)

Secretariat:
Dr L Foster (Administrative Secretary)
Dr P Cook (Scientific Secretary)
Mrs E Stretton
Mrs M Obeng

Others :
Mrs M Howell (FSA): agenda items 6 and 8
Dr J McLauchlin (HPA): agenda item 7
Mr I Gillespie (HPA): agenda item 7
Dr R Meldrum (NPHS, Wales): agenda item 9
Members of the public – see Annex I

1. Chairman's introduction

1.1 The Chairman welcomed ACMSF Members and members of the public to the 57th meeting of the Committee.

1.2 The Chairman also welcomed Mrs Mary Howell (FSA) who would be introducing agenda items 6 and 8. Dr Jim McLauchlin and Mr Iain Gillespie (both from the Health Protection Agency) were also welcomed, and would be presenting agenda item 7. In addition, the Chairman welcomed Dr Richard Meldrum (National Public Health Service, Wales) who would be presenting agenda item 9. The Chairman welcomed two ACMSF Members to the Committee – Mr Robert Rees and Mrs Vivianne Buller, who each provided a brief pen portrait. Lastly, he also formally welcomed Mr John Bassett to the Committee following confirmation of his previous temporary appointment.

1.3 Members were informed of the following re-appointments to the Committee: Professor Sarah O'Brien, Dr David Brown, Ms Sue Davies, Professor Mike Gasson, Professor Tom Humphrey, Mr Alec Kyriakides and Ms Eva Lewis.

1.4 The Chairman asked Members to identify any items for discussion under any other business at the end of the meeting. Professor Piddock indicated she wished to raise two items relating to the recent cuts in Health Protection Agency funding, and ESBL E.coli.

2 Apologies for absence

2.1 Apologies for absence were received from Dr Quentin Sandifer.

3 Declarations of interests

3.1 The Chairman reminded the Committee of the need to declare any conflicts of interests relating to items on the agenda. Professor Paul Hunter reported that, in connection with agenda item 6, the report on MAP risk factors was written by his team. Mr Kyriakides reported that, in connection with agenda items 8 and 9, Sainsbury's sold minced meat (agenda item 8) and poultry (agenda item 9).

4 Minutes of the 56th meeting (ACM/MIN/56)

4.1 Members approved ACM/MIN/56 as a correct record of the previous meeting. The Secretariat was asked to arrange for these final minutes to be posted on the Committee's website.
Action : Secretariat

5. Matters arising

5.1 The Chairman drew attention to the Secretariat information paper ACM/751 detailing matters arising from previous meetings. The Chairman informed members that individual actions would be kept on record until the outcome of the matter arising was known. In relation to illegally imported bush meat, Mr Mepham queried when the Committee would consider the use of seized meat to help quantify risk, exposure characterisation and animal origin. Dr Foster explained that this issue would be considered by the ad hoc Group on Imported Foods at its meeting on 4 October.
Action : Secretariat

5.2 There were no other matters arising identified by members of the Committee.

6. DWI report case control study on MAP risk factors

6.1 At the Chairman's invitation, Mrs Mary Howell (FSA) introduced paper ACM/752 explaining that despite extensive research and epidemiological studies no causal link had yet been demonstrated between Crohn's Disease and Mycobacterium avium subspp. paratuberculosis (MAP). She outlined the FSA's precautionary Strategy to reduce exposure to MAP in the milk supply. She then referred to the findings in a case control study of possible risk factors for Crohn's disease which, amongst other things, identified an unexpected positive association between meat consumption and Crohn's Disease.

6.2 Summing up, she sought the Committees' view on:

  • whether the findings in the case control study report associated with meat have any implications for current FSA advice on the consumption of meat
  • in light of the reference to a possible association between total animal protein consumption and Crohn's Disease, whether this specific point should be referred to the Scientific Advisory Committee on Nutrition (SACN).

6.3 In the ensuing discussion of the paper, Members raised the following points:

  • Members questioned whether the presentation had been discussed with the research group who undertook the study, Mrs Howell confirmed that it had not been
  • The study was well designed and conducted and the data analysis was thorough. The inclusion of the study questionnaire in the final report was welcomed. Members concluded that the findings of report did not suggest a need to change current FSA advice on consumption of meat. However the Committee requested that the FSA consider further the survival of MAP in solid foods. Action: FSA
  • It was not appropriate for the ACMSF to comment on reference to a possible association between total animal protein and Crohn's Disease. The Committee requested that the FSA seek an opinion on this matter from the Scientific Advisory Committee on Nutrition.
    Action: SACN Secretariat
  • Members queried whether the findings were nationally representative for Crohn's Disease as the study only obtained data from 5 regions. Professor Hunter informed Members that national data on Crohn's Disease was difficult to obtain due to regional variations in data collection. Patients included in the study were selected from hospital lists of patients diagnosed with Crohn's Disease.
  • MAP exposure would be greater via milk consumption than via meat consumption. Therefore, the lack of correlation shown between Crohn's disease and milk tended to argue against the association with meat being mediated via exposure to MAP. Professor Hunter confirmed that the study had shown a negative association between pasteurised milk consumption and MAP, and that this formed a key part of the work.
  • Private water supplies were not identified as a risk factor associated with Crohn's Disease. Members also noted that the causative effect of an association with meat consumption could be due to impact on the other microbiological flora of the bowel.
  • The wording for standard FSA advice for consumers on cooking of meat and meat products was reproduced in this paper. Paper ACM/754 additionally included other FSA sources of advice where the wording differed, and required amendment in order to be consistent.
    Action: Secretariat

6.4 The Chairman thanked Mrs Howell for her presentation, noting that her introductory paper intentionally only focussed on part of the studies findings, and did not attempt to cover the whole of the report.

7 Update on Listeria (ACM/753)

7.1 At the Chairman's invitation Dr McLauchlin and Mr Gillespie (HPA) presented paper ACM/753, which reviewed the changing pattern of human listeriosis in England and Wales from 2001-2004.

7.2 Dr McLauchlin outlined the history of listeriosis. Mr Gillespie presented data on sporadic cases of listeriosis over the last decade and data on non-pregnancy associated sporadic listeriosis and sites of infection in England and Wales. He explained that there had been a rise in non-pregnancy related listeriosis in the 60 years and over age group. Although common source food outbreaks of listeriosis had been identified, these constituted only a small proportion of the total number of cases. The increase could not be explained by current knowledge of the epidemiology of listeriosis. Dr McLauchlin added that the presentation of human listeriosis had changed, as now only 10% of total cases were pregnancy associated, and many cases now presented as bacteraemia without any neurological symptoms.

In response to this rise in cases of non-pregnancy related listeriosis, HPA suggested developing laboratory, epidemiological and microbiological initiatives to improve outbreak recognition and increase understanding of prevalence, levels and types of Listeria monocytogenes in high risk foods.

7.3 In the ensuing discussion of the paper, a number of points were made:

  • Listeria typing data would not indicate whether the pathogen had acquired new properties. Whilst it was possible to detect two of the virulence genes, there was no information available to assess whether the pathogen had acquired additional genetic factors. However, all strains of Listeria appeared to exhibit similar behavioural properties.
  • The rise in non-pregnancy related listeriosis in the 60 years and over age group was of concern, particularly as this sector of the population was increasing. Consideration needed to be given to the levels of Listeria in foods implicated in outbreaks, and whether some infection occurred due to repeated exposure to low levels of Listeria.
  • Advice on foods to avoid may need to be different for different age groups e.g. pregnant women and the 60 years and over age group. For example, the usual high risk foods may not be relevant. Members noted HPA were collecting epidemiological information via questionnaires administered to all cases of listeriosis, but the quality of data was constrained by the fact that many of these were elderly or seriously ill.
  • A recent 7-fold increase in bacteraemia was noted but no change in cases presenting with neurological symptoms or in bacterial serotypes had occurred. Members queried whether the rise could be an artefact, for example, due to a change in blood culture media used to culture organisms. HPA responded that over the last 6 years the proportion of deaths had remained constant and noted that the organism was not nutritionally demanding.
  • A similar rising trend in Listeria cases had been reported in Scotland, Belgium, Finland, Germany and the Netherlands in 2002. There was no significant increase in cases in Northern Ireland.

7.4 In summing up, the Chairman recognised the there were data limitations, but given the clinical importance and change in presentation of this disease, the ascertainment issue needed to be ruled out. He recommended that the FSA consider the need for provision of further research and surveillance resources (epidemiological and food) to investigate Listeria. He added that any surveillance should consider unusual foods for the presence of this pathogen. Lastly, the Chairman requested that this agenda item be marked forward for review in June 2006.
Action: FSA/Secretariat

8 Microcriteria proposals – requirements for Salmonella in minced meat (ACM/754)

8.1 At the Chairman's invitation Mrs Mary Howell (FSA) introduced paper ACM/754. She explained that new legislation on the microbiological criteria for foodstuffs comes into force on 1 January 2006. This legislation will require minced meat preparations and certain meat products to be clearly labelled at the point of sale informing the consumer of the need for thorough cooking prior to consumption. Mrs Howell outlined the proposed Salmonella criteria for these products and details of a transitional derogation for Salmonella in products designed to be cooked prior to consumption. She also summarised other labelling requirements and previous ACMSF advice to consumers on the cooking of meat and products thereof. Mrs Howell explained that the Agency was seeking the views of the ACMSF as to what appropriate information should be included in the labelling of these types of meat, as the FSA was looking to suggest wording to form part of best practice guidelines. In particular, what type of wording/information should labelling include, whether different wording would be applicable to products benefiting from the transitional derogation, whether time/temperature requirements should be considered, and whether use of symbols would be appropriate.

8.2 In considering these issues, Members agreed that:

  • This issue should preferably be considered as part of a wider discussion on labelling.
  • The 'Safer Food Better Business' guidance package for catering businesses already included pictorial information/symbols relating to cooking of meat products, based on the Agency's 4C's Campaign.
  • It was not appropriate to have different labelling for meat falling under the transitional derogation arrangements. Labelling needed to be consistent for all products.
  • It was recognised that labelling meat with time/temperature combinations was not practical as consumers tended not to use meat thermometers or probes. Such measures would be counter-productive. However manufacturers' instructions for oven temperatures and times should be followed. There were also difficulties associated with printing large amounts of information/symbols on labels designed for loose products.
  • The risks associated with the presence of other pathogens such as E.coli in meat also need to be considered.

The Chairman thanked Mrs Howell for her presentation. In summing up, he reiterated that the Committee did not support use of overly prescriptive wording and that appropriate wording should be applicable to all retailers (including those selling loose products). There was a need for consistency of labelling - wording should not be different for products falling under the derogation. In addition, target time and temperature combinations were not required or appropriate for cooking advice aimed at consumers. Finally, the Committee supported use of symbols, but only in conjunction with use of appropriate wording.

9 Update on poultry surveillance (ACM/755)

9.1 At the Chairman�s invitation, Dr Meldrum (NPHS, Wales) presented paper ACM/743, updating Members on the findings of a 2004 survey of Salmonella and Campylobacter contamination of raw poultry on retail sale in Wales and Northern Ireland.

9.2 Dr Meldrum provided an overview of the survey's objectives, sampling protocols and methodology, data on Salmonella and Campylobacter rates between 2001 and 2004, and a comparison of findings from samples taken from retailers and butchers, and fresh and frozen samples.

9.3 Members discussed the provenance of chicken samples, noting that frozen chicken was more likely to be imported for use in catering establishments. Salmonella was more likely to occur in frozen than in fresh chicken due to use of processing techniques such as water immersion chilling. Dr Meldrum reported that most samples collected for the survey were standard broilers which were widely available. Limited sample numbers precluded analysis of Kosher, Halal and free-range poultry.

9.4 Mr Kyriakides emphasised the need to take account of seasonal volumes of poultry retail sales when sampling retail premises in order to give a truly representative prevalence to assess the risk of exposure to pathogens. Professor Hunter added that when interpreting graphical seasonal data there was a need to be aware of random or chance factors occurring from month to month.

9.5 Mr Gayford welcomed the work being carried out on Salmonella speciation, noting that no Salmonella Enteritidis isolates had been reported in the 2004 figures. He highlighted the importance of identifying pathogen species and the link to species occurring in humans.

9.6 The Chairman thanked Dr Meldrum for his update.

10. Committee sub-groups

Safe Cooking of burgers

10.1 At the Chairman's invitation, Professor Williams reminded Members that this short-life ad hoc Group had been set up following an approach to the FSA by a US burger chain concerning the stringent UK time/temperature cooking requirements for burgers. The second meeting of this Group took place on 2 August.

10.2 The Group was presented with information from Mr Bassett on data modelling approaches for the safe cooking of burgers. Professor O'Brien presented a paper to the Group outlining the epidemiology of E.coli O157. She also briefed the Group on historical outbreaks occurring in the UK and the United States.

10.3 At least one further meeting of this Group would take place prior to reporting the outcome of the Group's deliberations to the full Committee at its December meeting.

Working Group on surveillance

10.4 At the Chairman's invitation, Professor Humphrey, reported that the Surveillance Working Group had been asked to comment on the draft survey protocols for the testing of non-UK eggs on retail sale and UK and non-UK eggs in catering premises for the presence of Salmonella. He suggested that the Committee consider the design of sampling programmes and sample numbers at a future meeting.
Action: Secretariat

10.5 Professor Humphrey also requested that, following receipt of comments from the Working Group, the FSA provide the Group with feed-back.

Action: FSA

Newly-emerging pathogens

10.6 At the Chairman's invitation, Professor Hunter reported that there had been limited activity via the message board as no major threats to the food supply had been identified over the period in question.

10.7 The Chairman requested that Members proactively place emerging items of interest to the Committee on this message board, via the Secretariat.

Action: Members

Botulism in cattle

10.8 The Chairman informed Members that since the last meeting, the Group and Secretariat have been working by correspondence to progress the draft report of this work. A further meeting of this Group was scheduled for early November to finalise the report. It was anticipated that the Group would present the outcome of its deliberations to the Committee at the December ACMSF meeting.

10.9 The Chairman thanked all the Chairs of the Sub Groups for their contributions.

11. Dates of future meetings (ACM/756)

11.1 The Chairman brought to Members' attention paper ACM/756 which listed the dates for remaining ACMSF meetings in 2005, and for meetings scheduled for 2006.

12. Any other business

12.1 Professor Piddock requested a response from the FSA regarding a point raised at the March meeting relating to the impact of the reduction in HPA funding on the availability of surveillance and epidemiological data. Dr Hilton replied that no change had been observed on the availability and quality of data provided by HPA since the re-organisation of laboratories. Issues relating to the late receipt of foodborne disease surveillance data had previously been identified before this took place. No further deterioration in timeliness or data quality had yet been observed. The Chairman reiterated the need for provision of adequate resources in order to carry out surveillance, and that any reduction in resources would impact adversely on the work of the Committee. He requested that the FSA ensure the Committee is provided with data from HPA in a timely manner.

Action: Secretariat

12.2 Professor Piddock informed the Committee of an increase in multi-drug resistant E.coli infections. Referring to a recent paper published by the HPA on multi-drug resistant ESBL (Extended Spectrum B-Lactamase) producing E.coli strains causing infections, she asked about the suggestion that this increase might be linked to transmission through the food chain. Dr Hilton noted that there had been an increase in acquisition of these infections in the community. However, before tackling the source of infection, it was important to establish the extent to which such pathogens were prevalent in the community as part of the normal bowel flora. Dr Hilton added that, whilst the HPA paper was clear on this, the accompanying press release linking the increase to transmission through the food chain, was misleading.

12.3 Referring to information paper ACM/759 Mr Mepham queried how the reported reduction in incidence of Campylobacter was linked to the interventions of the Foodborne Disease Strategy. He also asked what items were covered in the FSA report of the Strategy's expenditure. Dr Hilton explained that the Strategy was based on an overall target for reduction of foodborne disease, and that Campylobacter was the largest source of cases of foodborne illness. No one single part of the Strategy could be linked to the decrease in Campylobacter. However, the Food Hygiene Campaign, particularly in relation to cross-contamination messages, could have played a part in this. She added that the FSA worked in partnership with industry and Local Authorities to achieve the Strategy, and that the costings presented in the paper did not reflect expenditure incurred by these parties.

12.4 Mr Gayford informed Members of an initiative recently launched by industry on Johnes Disease and provided leaflets on this initiative for the information of Members.

13. Public questions and answers

13.1 The Chairman invited the members of the public present to ask any questions they might have on the work of the Committee, or to make any observations.

13.2 Dr Bernard Rowe discussed the availability of phage typing data for isolates, noting that in its recently published Campylobacter Report, the ACMSF had discounted phage typing of Campylobacter and recommended application of MLST typing tools to improve epidemiological understanding of Campylobacter. However, in the poultry surveillance paper, the vast majority of isolates were typable by phage typing. Professor O'Brien explained that the Report had considered the use of serotyping and phage typing to examine possible epidemiological linkages between cases and food sources. Neither of these typing methods were helpful in this respect. She added that the Health Protection Agency was now moving away from using phenotyping techniques for Campylobacter.

13.3 Alan Proctor informed the Committee that he had been campaigning for the eradication of avian TB (MAP) from the food chain since 1995. He noted that hospital admissions for Crohn�s Disease had doubled over the last 15 years, and requested that the Committee consider a recent EU report on Crohn's Disease. He also outlined a skin screening test used in cattle to eliminate animals with bovine TB from the herd, and suggested that this test could also be used to detect animals with Johnes Disease. Finally he queried whether the MAP in milk survey would be repeated.

13.4 Mr Gayford explained that the skin test could not be used to detect Johnes infected cattle, and that it would be uneconomic to remove animals carrying MAP from the herd. He added that it was not known whether milk consumption would exacerbate development of Crohn's Disease. Dr Hilton commented that that FSA was intending to repeat the MAP in milk survey once interventions intended to reduce MAP in milk had been identified and put in place.

13.5 Mr Long (Vega Research) queried why the Committee focussed its discussions on food from animal origin only, and also whether the Committee had considered issues surrounding avian flu. The Chairman explained that meeting agendas were risk-based and covered all areas of microbiological risks associated with food. He added that dealing with emerging protocols for the identification of influenza in birds or controlled culling fell outside the remit of the Committee. However, Dr David Brown was keeping a watching brief for the ACMSF on developments in relation to avian flu. Lastly, he commented that avian flu could not be transmitted through the food chain.

14. There being no further business, the Chairman thanked Members and members of the public for attending and closed the meeting.

Annex I

Members of the public attending the 22 September ACMSF Meeting

Mrs K Cheesman – Food & Drink Federation
Ms K Dinsdale – ADAS
Ms K Goodburn – Chilled Food Association
Mr A Long – VEGA
Dr B Lund – IFST
Ms A Lyon – Greggs Group Technical Centre
Mr T Marsh
Dr D McCleery – Safefood
Mr T Miller – Food Regulatory Affairs Consulting Ltd
Ms G Mulholland – DEFRA
Mr A Procter – Zhita International
Dr B Rowe
Dr P Voysey – CCFRA