ACMSF minutes: 15 March 2007

The 62nd meeting of the ACMSF was held at 10.30am on 15 March 2007 in Aviation House, London.

Professor S O’Brien

Mr J Bassett
Mrs V Buller
Ms S Davies
Prof. M Gasson
Mr A Kyriakides
Ms E Lewis
Dr S Millership
Mrs J Morris
Prof. L Piddock
Prof. P Williams

Mr P Gayford (Defra)
Dr J Hilton (FSA)
Dr S Neill (DARDNI)

Dr L Foster (Administrative Secretary)
Mr Ade Adeoye
Miss Sarah Butler

Ms Elizabeth Andoh-Kesson, BMPA
Mr Steve Batchford, Brakes
Mr John Charap
Dr Charmaine Clarke, Safefood, Ireland
Mr David Clarke, Assured Food Standards
Mr Andrew Curtis, Food and Drink Federation
Mr Kirsty Dinsdale, ADAS
Mr Andrew Frost, Defra
Mrs Barbara Gallani, British Retail Consortium
Ms Kaarin Goodburn, Chilled Food Association
Dr Chris Houston, Defra
Mr Sean Humber, Leigh Day & Co
Miss Fiona Lock, Defra
Mr Alan Long, VEGA
Mrs Ishbel MacKinnon, HUSH
Miss Gemma Mulholland, Defra
Mr Rick Pendrous, Food Manufacture magazine
Mr Alan Proctor, Zhitz International
Mr Steve Nash, HUSH
Mr Stephen Wyllie, Defra

Chair's introduction, apologies for absence and declarations of interest
1.1 The Chair welcomed ACMSF Members and members of the public to the 62nd meeting of the Committee. She also welcomed Dr Edward Guy (NPHS Wales) who would be presenting agenda item 6 and Dr Joanne Aish (FSA) who would be presenting agenda item 7.

1.2 The Chair informed Members that the agenda item reviewing the recommendations of the ACMSF Report on microbial antibiotic resistance in relation to food safety would be discussed at a future meeting. Two additional items on Avian influenza and the Epidemiology of Foodborne Infections Group had been added to the agenda for the meeting.

1.3 She asked Members to identify any items for discussion under any other business at the end of the meeting. None were identified.

2. Apologies for absence

2.1 Apologies for absence were received from Dr David Brown, Professor Tom Humphrey, Professor Paul Hunter, Mr Paul McMullin and Mr Robert Rees.

3. 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 Kyriakides informed Members that, in relation to agenda items 6 and 7, his employer sold cured meats, lamb and goat products.

Minutes of the 61st meeting (ACM/MIN/61) and matters arising
4.1 Members approved ACM/MIN/61 as a correct record of the previous meeting. The Secretariat was asked to arrange for final minutes to be posted on the Committee’s website.

Action: Secretariat

5. Matters arising

5.1 The Chair drew attention to the Secretariat information paper ACM/827 detailing matters arising from previous meetings. Professor Piddock formally recorded her concern that, in relation to paper ACM/838, no postgraduate studentships on microbiology had been commissioned since 2005.

Toxoplasmosis and food (ACM/828)
6.1 At the Chair’s invitation, Dr Edward Guy (NPHS Wales) presented an overview of human toxoplasmosis in the UK and other countries. He reviewed the findings of three major studies carried out in the Netherlands, Europe and the USA. He also outlined the routes of Toxoplasma gondii transmission. These were via the environment (soil, water), and the food chain from crops through insufficient washing of vegetables and from animals (consumption of raw or undercooked meat). He explained that the cat was the definitive host for this organism. Risk factors for acquiring toxoplasma infection, incidence of infection and burden of disease in the UK were also discussed and approaches to risk assessment were briefly reviewed.

6.2 In the ensuing discussion the Committee:

  • Reviewed the limitations of the three published studies presented noting that the Netherlands study assessed incidence of toxoplasmosis based on the assumption that all cases were foodborne, and did not take account of environmental sources of transmission. A European study carried out in 2000 did not gather information on consumption of salads or vegetables and one third of cases could not be attributed to any source. Members queried why there was no risk associated with the cat (definitive source of T. gondii) in the EU study and highlighted the difficulties of extrapolating conclusions from work based on cat ownership in other countries to the UK.
  • Identified several data gaps and unknowns with respect to risk factors for toxoplasmosis in the UK. These included the impact of climatic conditions on environmental incidence of the organism, and differences in socioeconomic groups and cultural aspects. Members agreed that more information to assess the prevalence of T. gondii in the food chain was needed including data on incidence and heat inactivation of the parasite to assess the risk posed by consumption of undercooked meat. Members agreed that all these factors required investigation. In addition, any commissioned work to assess the incidence of T. gondii in food would need to run in parallel with any human epidemiology studies.
  • Concluded that there was insufficient data available to recommend changing advice on whole cuts of meat.
  • Considered that any consideration given to increasing surveillance of foods would need to reflect the significance of the risk posed by this disease.
  • Noted that T. gondii cysts spread throughout meat muscle and that these cysts were inactivated by freezing at -20ºC. Therefore freezing meat prior to consumption minimised risk of infection.
  • Noted that historically there was a high risk of Toxoplasma re-activation in HIV patients although this was reduced by newer HIV treatments.
  • Noted that typing work showed that T. gondii was very similar to Cryptosporidium with types I and II being associated with different levels of pathogenicity.

6.3 The Chair thanked Dr Guy for his presentation. She concluded that, at the present time, there was insufficient data available to recommend changing cooking advice on whole cuts of meat. Therefore she suggested that the ACMSF ad hoc Group on vulnerable groups consider the risks posed by Toxoplasma in food in more detail. Defra registered an interest in being involved in these discussions.

Action: Secretariat/Professor Hunter

6.4 Lastly, Dr Hilton informed Members that the Agency had work in progress on sampling carcass meat at abattoirs which included work on Toxoplasma. She agreed to clarify whether the Microbiological Safety Food Funders Group had considered toxoplasmosis.

Action: Dr Hilton

Botulism in sheep and goats (ACM/829)
7.1 At the Chair’s invitation Dr Joanne Aish introduced paper ACM/829. She reminded Members that following comments received in response to the consultation on botulism in cattle report, the ad hoc group on botulism in cattle had agreed that the potential risk to human health from food chain issues linked to botulism or suspected botulism in sheep and goats should be considered as a separate issue.

7.2 She explained that paper ACM/829 therefore sought the Committee’s advice on whether the current recommendations for botulism in cattle lifting voluntary restrictions on meat and milk from healthy cattle from farms where there have been suspected cases of botulism could also be applied to meat and milk from healthy sheep and goats where there have been suspected cases of botulism.

7.3 Members recognised that although there may be similarities in progression and onset of the disease, the Committee would need to explore issues surrounding epidemiology, route and transmission of the disease in sheep and goats. The Committee proposed that the ad hoc group on botulism in cattle should be reconvened to examine these issues in more detail.

7.4 The Chair thanked Dr Aish for her presentation. She requested that the Secretariat reconvene the ad hoc group on botulism in cattle to examine evidence in relation to sheep and goats.

Action: Secretariat

Safe cooking of burgers
8.1 At the Chair’s invitation Professor Williams (Chair, ad hoc Group on safe cooking of burgers) presented paper ACM/830. He reminded Members that in June 2006 the Committee approved the draft report on safe cooking of burgers for public consultation. The consultation on this report took place between July and October 2006.

8.2 He explained that the group was set up to review the Chief Medical Officer’s 1998 advice on safe cooking of burgers and to report back to the ACMSF with recommendations. The group concluded that there was no evidence to support a relaxation in the advice. He added the CMO’s advice was therefore included in an Annex to the report.

8.3 A wide range of comments were received in response to the consultation which broadly fell into three categories: comments received which were supportive of the report; comments on detailed or technical issues (these were taken on board to improve the clarity and accuracy of the report); and comments relating to concerns on procedural aspects of the groups’ work and a misunderstanding relating to the recommendations about the advice. He explained that the group recognised the issues raised associated with E.coli O157 and added that the group had conducted its investigations in accordance with Nolan Principles.

8.4 The Chair thanked Professor Williams for his report. She confirmed that the Committee approved the consultation response for publication on the FSA web site and recommended the report for submission to the FSA for approval for final publication by June 2007.

Codex Food Hygiene meeting
9.1 At the Chair’s invitation Dr Cook presented paper ACM/832 which summarised the main outcomes of the 38th session of the Codex Committee on Food Hygiene (CCFH) which was held in Houston, Texas in December 2006. By way of background, he explained that historically the ACMSF was informed of the work of this Codex group which met every 12-18 months.

9.2 The Codex Committee agreed to advance three documents to the Codex Alimentarius Commission for adoption on guidelines for microbiological risk management, hygienic practice for eggs and egg products and guidelines on the application of general principles of food hygiene to the control of L. monocytogenes in ready to eat foods. The Committee also agreed to take forward new work on proposed guidelines for control of Salmonella and Campylobacter in broiler meat. Future work on noroviruses in shellfish, E.coli and fruit and vegetables was also discussed. Lastly, he reported that an FAO/WHO expert consultation on the uses of active chlorine was expected to be held in 2007.

9.3 The Chair thanked Dr Cook for his update and confirmed that these updates from the Codex Food Hygiene meetings were valuable for the ACMSF.

Committee sub-groups and EFIG

Working Group on Surveillance

10.1 In the absence of Professor Humphrey the Chair informed Members that there was nothing to report as the group had not met since the last meeting. The next meeting of the Working Group on surveillance was scheduled for 11 May. At this meeting the group would discuss the final reports of two FSA surveys on smoked fish and catering eggs.

Newly-emerging pathogens

10.2 In the absence of Professor Hunter, the Chair 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.

Vulnerable Groups

10.3 The Chair reported that the Secretariat was in the process of setting up a new Group on vulnerable groups which was scheduled to meet in April.

Avian influenza

10.4 At the Chair’s invitation Dr Hilton updated the Committee on the recent avian influenza incident which took place in February. She explained that the outbreak began at the beginning of February on a turkey farm in Norfolk. One out of 22 sheds was affected. All the birds on the farm were killed and the farm was disinfected. Required restriction zones were put in place at 3km, 10 km which encompassed SE Norfolk and NE Suffolk. At the time of this meeting these restrictions had been lifted as there was no reported spread of the virus beyond the farm premises. Originally it was thought that the most likely route of virus transmission was via wild bird introduction (gulls). However after one week it became apparent the virus strain was very similar (99.9%) to that linked to an outbreak in Hungary. Therefore it was considered unlikely that the virus had been transmitted via wild birds although there was some evidence of wild birds accessing waste products from the cutting plants. The Norfolk turkey farm also owned a factory in Hungary and this meat plant had transported meat from other parts of Hungary. She added that during the incident the FSA carried out an investigation to ensure that no turkey meat from control zones in Hungary reached the UK.

10.5 Dr Hilton reported that the investigation was still ongoing and that the source of infection had not been confirmed. Work was in progress to tease out the complications relating to the epidemiology of the disease in birds.

10.6 The Chair thanked Dr Hilton for her update. She requested that the Working Group on Avian Influenza reconvene to discuss any new information arising as a result of the incident.

Action: Secretariat

Epidemiology of Foodborne Infections Group (EFIG) (ACM/833)

11.1 At the Chair’s invitation Dr Hilton (Chair, EFIG) introduced paper ACM/833 which updated Members on the most recent meeting of the Epidemiology of Foodborne Infections Group held on 1 March 2007. She reviewed animal and human data for the second six months of 2006, and briefed Members on discussions surrounding sorbitol-fermenting VTEC O157 and highlights from the VTEC 2006 conference. Other issues considered by the Group included a presentation on a Campylobacter case control study involving around 1700 cases and over 3000 controls. A report of the EU layer flock Salmonella survey was presented followed by an update on proposals for investigation of the increase in non-PT4-Salmonella Enteritidis. Information on recent patterns of non-UK egg sourcing was also presented which showed a decrease in sourcing from Spain and increased sourcing from Germany. The group also received a presentation on RADAR, a veterinary surveillance system that brings together animal surveillance and population data. Lastly the Group considered antimicrobial resistance, specifically in relation to extended spectrum beta-lactamase (ESBL) producing E.coli.

11.2 Dr Hilton reported that the Defra Antimicrobial Resistance Committee had suggested that consideration should be given to the potential role of the food chain in transmission of ESBLs. Since the Standing Advisory Committee on Antimicrobial Resistance was about to be disbanded, EFIG had suggested that ACMSF should be invited to consider this issue.

11.3 Members welcomed the paper and noted that there were difficulties linked to detecting sorbitol-fermenting E.coli O157. Mr Gayford commented that Defra was directing its resources to look at E.coli. Professor Piddock welcomed the information on antibiotic resistance and ESBLs and reiterated that this issue should be revisited. She added that a broader look at antibiotic resistance was needed to assess whether the picture had changed since the ACMSF last considered this issue in 1999. Mr Gayford outlined Defra’s concerns in relation to ESBLs noting that enhanced surveillance had been in place since 2004 and that an increasing number of isolates had been detected in animals.

11.4 The Chair thanked Dr Hilton for her update. Summing up, she concluded that the points regarding antibiotic resistance were well made. She suggested that ACMSF consider the wider issues surrounding antibiotic resistance in the medium term once the Committee had recruited the appropriate expertise following Professor Piddock’s departure. She requested that the ad hoc group on emerging pathogens examine ESBLs in food in the first instance and report back to the Committee with recommendations.

Action: Secretariat/Professor Hunter

Date of future meetings (ACM/834) and any other business
12.1 The Chair brought to Members’ attention paper ACM/820 which listed the dates for meetings scheduled for 2007 and provisional dates for 2008. She reminded Members that all meetings were open to members of the public.

Any other business

13.1 Mr Bassett referred to paper ACM/835 and asked whether the Committee would receive any further information on outputs from the surveillance database. Dr Hilton replied that EFIG would consider the database once it contained data and that she would report back to the ACMSF.

13.2 Mr Bassett drew the Committee’s attention to paper ACM/837. Referring to paragraph 10 of this document he requested that the ACMSF receive a presentation from FSA or VLA on probabilistic risk assessment techniques in the food chain.

Action: Dr Hilton/Secretariat

Public questions and answers

14.1 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.

14.2 Mr Rick Pendrous (editor, Food Manufacture) referred to the information presented by Dr Guy on toxoplasmosis noting the lack of data available on sources of this organism in the food chain. He queried whether the ACMSF were aware of work by AFSSA on routes of toxoplasmosis in French meat herds. The Chair replied that the Committee had discussed selected data presented at the meeting and that it was aware of the work in Europe. She added that the Committee ad hoc Group on vulnerable groups would consider the French work in more detail.

14.3 Mr Alan Proctor (member of the public) commented on toxoplasmosis and raised several points relating to Crohn’s disease. He mentioned a graph depicting the increase in hospital admissions linked to Crohn’s disease since 1997. The Chair commented that Crohn’s disease was a complicated illness and that there were several potential risk factors, the most significant of which appear to be genetic. With reference to the graph mentioned by Mr Proctor, she commented that there were difficulties associated with examining one set of data in isolation as there were several contributing risk factors which needed to be considered. Dr Hilton commented that the FSA had a strategy in place considering MAP and milk which was being taken forward. She added that a recent case control study had shown that milk had a protective effect against Crohn’s disease. She also explained that research on heat sensitivity had shown that the presence of MAP in milk was more likely to be due to post pasteurisation contamination in the factory than to organisms surviving the heat treatment.

14.4 Mr Andrew Frost (Defra) commented on the toxoplasmosis information presented to the Committee noting that the European study was city based. He queried whether the current case study being undertaken by HPA and NPHS Wales would be undertaken on a national basis. Dr Guy replied that the HPA study would involve follow-up of cases nationally. The Chair added that the ad hoc group on vulnerable groups would consider culinary cultural practices as part of its examination of toxoplasmosis and the food chain.

14.5 Mr Sean Humber (HUSH) made several comments relating to the rationale behind the safe cooking of burgers report. He queried the ACMSF’s recommendation that the CMO’s advice on safe cooking of burgers had not changed as the report also recommended the use of time/temperatures equivalent to 70ºC for 2 minutes. He also referred to paragraph 78 in the report noting a recommendation for the production of guidance on use of appropriate time/temperature controls for industry and enforcement officers. He also commented on the consultation process. The Chair explained that the ACMSF dealt with risk assessment issues and that the FSA would be responsible for considering whether to develop guidance on use of appropriate time/temperature controls for industry and enforcement officers as this was a risk management issue. She reiterated that the recommended advice stated that burgers should be cooked for 70ºC for 2 minutes or equivalent which was in line with the CMO’s advice. Any process that deviated from these conditions must be shown to achieve the same reduction in E.coli O157 as would be achieved through cooking for 70ºC for 2 minutes. She acknowledged that HUSH was unhappy with the consultation process. She explained that prior to this report, several other ad hoc ACMSF reports had been subjected to public consultation and that this was usual ACMSF practice for technical reports of this nature.

14.6 Mr Nash (HUSH) raised several queries on the safe cooking of burgers report relating to guidance for manufacturers, caterers and consumers, the identity of anonymous references and the US fast food restaurant chain mentioned in the report. The Chair replied that the name of the restaurant chain was listed in Annex 2, and that use of ‘Anon’ was an accepted scientific convention when listing references for papers with unassigned authors. She added that the ACMSF recommendations in paragraph 80 fell to the FSA to consider as these related to risk management issues.

14.7 Mr Alan Long (VEGA) commented on several issues relating to use of land for food production, diseases carried by horses and young calves, silage and on farm biosecurity, silage.

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