ACMSF minutes: 1 December 2005

Meeting held at Trinity House, Tower Hill, London EC1


Professor B Reilly

Dr D Brown
Mrs V Buller
Professor M Gasson
Professor T Humphrey
Professor P Hunter
Mr A Kyriakides
Mr P McMullin
Mr P Mepham
Professor S O'Brien
Professor L Piddock
Mr R Rees
Professor P Williams

Mr P Gayford (DEFRA)
Dr S Neil (DARDNI)

Dr L Foster (Administrative Secretary)
Dr P Cook (Scientific Secretary)
Mrs E Stretton
Ms S Butler

Others : Members of the public - see Annex I

Chair's introduction, apologies for absence and declarations of interest
1.1 The Chair welcomed ACMSF Members and members of the public to the 58th meeting of the Committee.

1.2 The Chair asked Members to identify any items for discussion under any other business at the end of the meeting. Dr Cook indicated he wished to raise an item relating to recently published guidance on bottle-feeding for infants. The Chair informed members that he wished to raise an item relating to the appointment of a Deputy Chair to the Committee.

1.3 The Chair informed Members of two changes to the agenda. Information paper ACM/771 had been withdrawn and would be made available at the March 2006 meeting. An alternative information paper (ACM/776) on Campylobacter and poultry had been provided.

Apologies for absence
2.1 Apologies for absence were received from Mr John Bassett, Ms Sue Davies, Dr Kay Hadley, Dr Judith Hilton, Ms Eva Lewis, and Dr Quentin Sandifer.

2.2 The Chair informed Members that Dr Cook would be acting as the FSA Assessor in the absence of Dr Hilton.

Declarations of interests
3.1 The Chair reminded the Committee of the need to declare any conflicts of interests relating to items on the agenda. Mr McMullin reported that, in connection with agenda items 7 and 11, his company provided veterinary services to primary producers. Professor Humphrey reported that, in connection with agenda item 10, he had provided South Wales Police with advice on storage of foodstuffs.

Minutes of the 57th meeting and matters arising
4.1 Members approved ACM/MIN/57 as a correct record of the previous meeting, subject to the deletion of the word 'phage' in paragraph 13.2. The Secretariat was asked to arrange for these final minutes to be posted on the Committee's website.
Action : Secretariat

Matters arising
5.1 The Chair drew attention to the Secretariat information paper ACM/763 detailing matters arising from previous meetings. Mr Mepham queried whether additional information requested from the Health Protection Agency (HPA) on the origin of foods associated with outbreaks of foodborne disease had been circulated to the ad hoc Group on imported foods. Dr Foster confirmed that a line listing of relevant outbreaks was provided to Group members, shortly after the ad hoc Group meeting in October. Dr Brown declared an interest as an employee of HPA. He commented that HPA's current data set did not allow a detailed assessment of the origin of foods.

5.2 Professor Humphrey declared an interest as an ex-employee of the Public Health Laboratory Service. He reiterated previous concerns relating to the impact of cuts in funding on the timeliness and quality of data from HPA. With the support of the Committee, he suggested that senior HPA officials should be invited to discuss this issue with the Committee.

5.3 Summing up, the Chair requested that the FSA invite HPA to address this funding issue directly with the Committee.
Action : Secretariat

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

Ad hoc Group on Imported Foods - final report
6.1 At the Chair's invitation, Mr Philip Mepham introduced paper ACM/764. He explained that since the last report of this ad hoc Group to the Committee in December 2003, the work of the Group had focussed on two areas. These were foods of non-animal origin and bush meat. He outlined previously reported conclusions reached by the Group relating to foods of non-animal origin. These were that:

1) More information was needed in order to decide whether sufficient was being done to manage the microbiological safety of foods of a non-animal origin entering the market.

2) The systematic approach to surveying and capturing information on foodborne diseases in other countries could lead to improved safety of imported foods. This additional safeguard was dependent upon such information being used to identify potential risks that could then be effectively communicated to all of those involved in managing the safety of imported food. This should not be restricted to foods of animal origin.

3) Further consideration was needed on the role of traceability systems given their importance for effectively identifying and controlling microbial hazards and as part of this, gaining a clearer understanding of the risk posed from imported foods. Members acknowledged that traceability controls had recently come into force, thus their effectiveness was as yet unknown. This requirement would facilitate development of improved investigation techniques.

4) Due to the limited reporting of provenance data, few reported outbreaks have been attributed to imported foods. Effort was needed to collate more detailed information in order to establish the origin of foods implicated in outbreaks.

5) Further information was needed to assess the risk associated with the microbiological safety of imported food under the forthcoming legislative framework.

6) There was a need to monitor developments in co-ordination of import controls, as it was critical to the effective management of the safety of imported food.

6.2 Key recommendations arising from the work of the Group were that:

1) The ACMSF should keep a watching brief on foods of non-animal origin and that the Committee request an annual update from HPA on trends in outbreaks and food vehicles linked to imported foods.

2) Local authorities and other bodies involved in monitoring and management of outbreaks of foodborne disease should also investigate the origin of food and ingredients implicated in outbreaks, recognising that recently implemented traceability legislation may have a role in the development of improved investigation techniques.

6.3 Mr Mepham summarised the outcome of the Group's deliberations following its consideration of an Agency-funded review of the microbiological risks of illegal imported bush meat, information on controls in place to prevent illegal imports, and research currently in progress on species identification of seized meat. This work was being carried out in light of comments made at the June 2005 ACMSF meeting.

6.4 The Group concluded that:

1) The risk of foodborne illness from consumption of bush meat appeared to be very low, and the risk of foodborne illness from cross contamination was also minimal.

2) Normal cooking would probably destroy any viruses and bacteria present, although there was no data available to verify this.

3) There was a lack of quantitative data relating to the microbiological risks associated with bush meat.

6.5 In the light of these conclusions, the Group recommended that consideration should be given to the provision of funding to extend research currently in progress on DNA species identification. Such work should be preceded by a pilot study to assess the feasibility of the methodology to detect viruses in seized meat. Consideration should also be given to archiving any extracted DNA samples for future research.

6.6 The Committee welcomed the report on bush meat acknowledging that different viral infections occurred in different animals. Members supported extension of the research on DNA speciation commenting that modification of the extraction to examine both RNA and DNA viruses was technically achievable.

6.7 Members requested three modifications to paper ACM/764. These were to:

  • move the text outlined in Annex C, paragraph 10 to form part of the recommendations outlined in the front of the report
  • extend paragraph 9a) to also examine endemic disease in third countries that exported food to the UK
  • amend the first sentence of paragraph 9c) to read 'FSA consider'in order to include examination of viral DNA and RNA where possible in seized meat'
  • Action: Secretariat

6.8 Subject to these amendments to paper ACM/764, the Committee agreed that the ad hoc Group on Imported Foods had completed its activities and could therefore stand down.

Ad hoc Group on botulism in cattle (ACM/765)
7.1 At the Chair's invitation Professor Peter Williams presented paper ACM/765, which considered the potential risk to human health from botulism or suspected botulism in cattle, particularly in relation to the spreading of poultry litter on agricultural land.

7.2 Professor Williams outlined the scope of work undertaken by the Group over a period of 12 months and the nature of documentary and verbal evidence considered. Key areas subjected to examination were the molecular biology and structure of Clostridium botulinum, its toxins and process of delivery of the toxin from a food source to the neuromuscular junction; epidemiology and diagnosis of botulism in cattle, poultry waste, management of on farm botulism outbreaks in the UK, risk to public health, and public health advice.

7.3 Key recommendations and issues arising from the deliberations of the Group were that:

1) After absorption by affected animals it was unlikely that toxin produced by C.botulinum would be responsible for causing re-intoxication following consumption of meat from the affected cattle.

2) While clinical diagnosis was satisfactory for identification and clinical management of single cases and large outbreaks of botulism, it did not provide an adequate basis for implementation of food safety precautions such as exclusion of animal products from the food chain. Therefore, as part of outbreak investigations, the mouse bioassay should be applied to gastrointestinal samples to aid diagnosis and assess risk.

3) Work should be undertaken to understand the diagnostic and clinical significance of finding botulinum toxins in the gastrointestinal tract of cattle.

4) In view of concerns over the use of live mice for bioassays, consideration should be given to the development of other highly sensitive tests which did not use animals.

5) Samples collected during clinical investigations should be archived to assist method development.

5) DARNDI and VLA messages on use and disposal of poultry litter should be reinforced. Therefore FSA should work closely with the poultry industry to encourage good practice in litter management and disposal.

6) UK veterinary authorities should continue to encourage cattle farmers to report suspected cases of botulism in cattle.

7) FSA biosecurity messages to broiler farmers should be expanded to highlight the risks of disease transmission through deficient carcase removal practices.

8) There should be no requirement to restrict sales of milk from clinically healthy cattle from farms where there have been clinically suspected cases of botulism in cattle.

9) There should be no requirement to restrict the slaughter of healthy cattle from herds where cases of confirmed or suspected botulism have occurred, but meat and milk from clinically affected animals should not enter the food chain due to concern that this may pose a risk to consumers.

10) Laboratory evidence suggested that recent UK outbreaks were associated with toxin types C and D. However the risk to human health from the food chain should be re-assessed if other toxin types emerged.

7.4 Subject to minor editorial amendment to the document, the Committee agreed that the draft report would be submitted for public consultation, with a view to the report being finalised by the Committee in the first half of 2006. Members agreed to provide the Secretariat with editorial amendments prior to the report being issued for consultation. Mr Gayford agreed to provide specific comments relating to issues in Scotland.
Action: Members/Mr Gayford/Secretariat

7.5 Summing up, the Chair highlighted the key recommendation of the report, which proposed a change in current practice on the voluntary restriction of milk and meat from healthy cattle from affected herds. He also proposed that the draft report should be presented to a workshop on Clostridium botulinum and biowaste that was due to take place on 12 December. Lastly, he recorded his thanks on behalf of the Committee to the ad hoc Group and Secretariat for their efforts to prepare the report for this meeting.
Action: Secretariat

Hepatitis E (ACM/766)
8.1 At the Chair's invitation Dr David Brown introduced paper ACM/766. He explained that that Hepatitis E was a systemic infection that had been common in pigs for 20 years in the UK. During the past 10 years there had been reports from other countries of cases in humans associated with consumption of raw or undercooked meat (muscle) or offal from pigs and other mammals. He outlined recent published cases not associated with travel, noting that consumption of raw or undercooked meat and offal might be a risk factor for Hepatitis E in Japan. He explained that recent evidence indicated that only a small number of non-travel associated cases in humans had been identified in the UK to date, and that the risk of acquiring Hepatitis E through the food chain in the UK was likely to be low. The virus found in humans was similar to the virus found in pigs. He added that effective cooking would destroy any virus present in meat, and thus should prevent foodborne transmission. Lastly, he explained that better understanding of the burden of infection and transmission routes was needed in order to assess the risk to the food chain and to consumers.

8.2 The Committee discussed cooking advice for meat noting that terms such as 'effective cooking' and 'proper cooking' were difficult to interpret. Dr Cook explained that due to reductions in the levels of Trichinella occurring in pig populations in the European Union, current FSA advice that whole cuts such as meat joints did not need to be cooked all the way through had been expanded to include pork. Searing the outside of these products would destroy pathogens normally present on the surface. This advice did not apply to offal.

8.3 Members considered that searing the outside of meat joints would not be sufficient to destroy viruses such as Hepatitis E if they were present in muscle tissue. The Committee concluded that the FSA needed to review its advice on cooking of pork, and recommended that all pork and pig products (including liver) should be cooked all the way through.

8.4 Dr Brown explained that there was no direct evidence linking food as a route of transmission for UK reported cases. However there was evidence of such a link in other parts of the world where routes of transmission were established. He added that current understanding of the burden of disease was limited. There was no direct epidemiological data available to identify likely routes of transmission in the UK due to poor sensitivity of tests. Therefore most UK cases of Hepatitis E were not detected due to under reporting as this virus was not routinely tested for. Recent enhanced surveillance systems included testing of Hepatitis E, and these had resulted in an increase in the number of recognised cases. He was not aware of any cases in the UK associated with pregnant women (the group most susceptible to severe disease).

8.5 Members discussed the aetiology of the virus. Hepatitis E was an RNA type virus and therefore mutated quickly. Thus several types of virus could exist within the pig population making it difficult to assess links between human cases and cases originating from pigs.

8.6 The Chair thanked Dr Brown for his update. Summing up he requested that the FSA revisit its advice on cooking of meat, recommending that all pig products including liver should be cooked thoroughly. He recognised that more information was needed to increase understanding of the epidemiology of disease in humans and the presence of the Hepatitis E virus in pig populations and pig meat products. Lastly, he requested that the ACMSF revisit this issue in March 2006.
Action: FSA/Secretariat

E. coli O157 update (ACM/767)
9.1 At the Chair's invitation, Dr Cook (FSA) introduced paper ACM/767, updating Members on the recent outbreak of E.coli O157 in South Wales. He informed Members that this was the most serious outbreak of this nature that had occurred since the formation of the Food Standards Agency. He noted that some of the figures published in the paper had been updated. To date 172 cases of E. coli O157 had been linked with the outbreak, of which 133 had been microbiologically confirmed. Members were informed that the National Assembly for Wales had set up a Group to consider Terms of Reference for the Enquiry Committee. The FSA intended to consider lessons learned from the incident, and the outcome of a Review conducted by the Chief Medical Officer of Wales. An update would be provided to the ACMSF in due course. Lastly, Dr Cook emphasised that, as investigations into the cause of the outbreak were ongoing and might lead to legal proceedings, the release of information about this incident was restricted.

9.2 Members noted that the pattern of cases recorded in this outbreak had been observed previously. Professor O'Brien commented that as current cases being identified were secondary in nature, there might be lessons to be learned relating to controlling the spread of secondary infections within communities.

9.3 The Chair thanked Dr Cook for his update. He requested that this issue be retained as a standing item on the agenda and that the ACMSF should consider lessons learned from the outcome of the investigation at a future meeting.
Action: Secretariat

Avian flu update (ACM/768)
10.1 At the Chair's invitation Dr David Brown introduced paper ACM/768. He explained that, in 2003, the ACMSF reviewed a risk assessment that considered the risk to human health from acquiring avian influenza through the food chain. This assessment concluded that the risk of acquiring avian influenza through the food chain was low, and that there was no direct evidence to support this route of infection. In November a group of influenza virologists and epidemiologists, chaired by Dr David Brown, met to review new information and to consider the potential future risk to the UK from avian influenza. In summary the review group concluded that:

  • Following review of the existing 2003 ACMSF risk assessment and new information on human susceptibility to avian influenza, presence of avian influenza in eggs from affected birds, and ducks, no change was required to existing ACMSF advice;
  • Individuals involved in food handling and preparation might be exposed to the virus but the risk of this was low;
  • Additional risks in the event of high pathogenicity avian influenza circulating in the EU were low;
  • However a more detailed review of import control measures for poultry meat and eggs was required.

10.2 Members discussed the membership of the review Group. Although veterinary experts had been consulted in the preparation of paper ACM/768, Dr Brown agreed that veterinary expertise needed to be represented on the Group. Mr Gayford indicated that DEFRA wished be involved in further deliberations of the Group.

10.3 Members reviewed FSA advice for cooking of eggs noting that the advice to cook eggs properly was targeted to protect all consumers.

10.4 Mr McMullin confirmed that UK traceability controls would ensure early identification of avian influenza affected chickens.

10.5 The Chair thanked Dr Brown for his update. He noted that the Committee endorsed the conclusions reached by the review Group. The Committee also agreed that the existing risk assessment carried out in 2003 remained valid, noting that with regard to risks in the event of Avian Influenza circulating elsewhere in the European Union, a more detailed review of import control measures for poultry meat and eggs was required. Finally, he suggested that the Committee establish a Working Group to include DEFRA and veterinary experts to carry these forward and to keep a watching brief on developments.
Action: Chair/Secretariat

Committee sub-groups
11.1 The Chair informed Members that there was only one item to report other than those already covered in the agenda as the ad hoc Group on cooking of burgers had not met since the last ACMSF meeting. He added that the Working Group on Surveillance was due to convene that afternoon (1 December 2005). A full report of its activities would be provided at the March 2006 meeting.
Action: Secretariat

Newly-emerging pathogens
11.2 At the Chair'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.

Dates of future meetings (ACM/769)
The Chair brought to Members' attention paper ACM/769, which listed the dates for meetings scheduled for 2006.

Any other business
The Chair informed Members that, in line with procedures adopted by other Advisory Committees, he had invited Professor O'Brien to act as Deputy Chair of the ACMSF. The Committee unanimously supported this appointment.

12.2 Dr Cook informed Members that new Department of Health and FSA guidance on preparing infant formula had been recently published on the Agency's web site.

12.3 Mr McMullin drew Members' attention to information papers ACM/772 and ACM/773 commenting that a summary outlining the interaction between regulatory issues might be of interest to the Committee. The Chair agreed to discuss this issue with the Secretariat.
Action: Chair/Secretariat

Public questions and answers
The Chair 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.

Mr Steve Nash (HUSH) referred to discussions that had taken place at the September ACMSF meeting relating to the labelling requirements for Salmonella in minced meat (ACM/MIN/57, paragraphs 8.1 and 8.2 refer), and queried whether wider discussions on labelling had taken place. Dr Cook confirmed that he would seek a response from FSA officials.
Action: FSA

Mr Nash outlined issues relating to the labelling of cheeses made from raw milk, explaining that a recent communication from Brussels had upheld the view that cheeses made from raw milk must be labelled. This was also the view of the ACMSF and the E.coli O157 Task Force. Dr Cook explained that the FSA was aware of these developments. This issue was currently being reviewed, and stakeholders would be informed of any developments in due course. The Chair added that the ACMSF wished to remind the FSA that the Committee's recommendation to label cheeses made from raw milk had not changed.

As recorded at the previous meeting, Mr Alan Proctor referred to the FSA's intention to repeat the MAP in milk survey once interventions intended to reduce MAP in milk had been identified and put in place. He queried when this would occur. Dr Cook advised that there were no timescales currently available but reiterated the FSA's intention to carry out a further milk survey.

Mr Proctor also queried whether the use of poultry manure or poultry litter as animal feed was permitted. Mr Gayford agreed to provide a written response for circulation to Members at the next meeting.
Action: Mr Gayford

Mr Long (Vega Research) referred to the epidemiology of Johne's disease in cattle, noting that veterinary experts needed to consider the incidence of this disease in cattle. Mr Gayford explained that DEFRA was planning to carry out a two-year survey to examine Johne's disease in dairy cattle, which would commence in 2006. He added that the ACMSF had previously considered a DWI Report examining risk factors for Crohn's disease.

Mr Long also commented on the use of poultry manure as compost for growing mushrooms, querying whether such compost was subjected to pasteurisation as part of general precautionary measures to protect consumers. Mr Gayford agreed to provide a written response on this issue for circulation to Members at the next meeting.
Action: Mr Gayford

Other issues raised by Mr Long included the impact of the FSA's salt reduction target on butchering practices, and the impact of intensive cattle and poultry farming on the incidence of zoonotic disease. The Chair explained that the ACMSF had addressed microbiological risks associated with the result on salt in foods at a previous meeting.

Dr Barbara Lund (IFST) supported previous discussions on imported foods highlighting the need for information on foodborne disease from third countries exporting ready to eat foods into the UK. In response to her query relating to mycotoxins, Dr Cook explained that these substances were addressed by other Committees that provided advice to the FSA, and did not therefore fall within the remit of the ACMSF.

Mr Tom Miller (Food and Regulatory Affairs Consortium) queried the presence of the avian influenza virus in poultry or game muscle served rare, such as duck, and the impact of such cooking practices on the development of advice on eating these foods. The Chair explained that this issue would be considered by the Working Group on Avian Influenza, reiterating that avian influenza was not present in the UK food chain.

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