ACMSF 52nd minutes: 24 June 2004

Held at Aviation House, 125 Kingsway, London WC2B 6NH.

Present

Chairman
Professor W Reilly

Members
Mr J Bassett
Dr D Brown
Ms S Davies
Professor M Gasson
Dr K Hadley
Professor P Hunter
Mr A Kyriakides
Ms E Lewis
Mr P McMullin
Mr P Mepham
Dr S O'Brien
Mr B Peirce
Mr D Piccaver
Professor L Piddock
Professor P Williams

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

Secretariat
Dr L Foster (Administrative Secretary)
Dr P Cook (Scientific Secretary)
Mrs E Stretton
Miss C Wilkes

Others
Mr I Damon (FSA): agenda item 6
Ms G Hoad (FSA): agenda item 7
Members of the public – see Annex I

1. Chairman's introduction

1.1 The Chairman welcomed ACMSF Members, those making presentations and members of the public to the 52nd meeting of the Committee.

1.2 The Chairman paid tribute to the former Chairman, Professor Douglas Georgala, recognising that under Professor Georgala's Chairmanship, the Committee had been successful in its contribution to food safety.

1.3 The Chairman extended a particular welcome to the following new Members of the Committee; Professor Peter Williams, Professor Laura Piddock, Mr Paul McMullin and Mr John Bassett. He informed the Committee that Dr Katherine Hadley, Professor Paul Hunter and Dr Quentin Sandifer had been re-appointed for further terms.

1.4 The Chairman also welcomed Dr Lucy Foster who replaced Mr Colin Mylchreest as the Administrative Secretary to the Committee.

1.5 He explained the format of the meeting and dealt with a number of house keeping matters.

2 Apologies for absence

2.1 Apologies for absence were received from Professor Tom Humphrey. Apologies were also received from the following Departmental Assessors: Dr L Doherty (NIDHSSPS) and Dr G McIlroy (NIDARD), for whom Dr Neill was deputising.

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. Mr Bassett reported, in connection with agenda item 8, that he was involved in some of the risk assessment work reported to the ad hoc Group on Infant Botulism.

4 Minutes of the 51st meeting (ACM/MIN/51)

4.1 Members approved ACM/MIN/51 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/688 detailing matters arising from previous meetings.

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

6 Presentation on the Agency's new draft strategic plan (ACM/689)

6.1 At the invitation of the Chairman, Mr Ikpeme Damon from the Food Standards Agency's Strategic Development Unit gave a presentation on the Agency's draft Strategic Plan (paper reference ACM/689). Mr Damon reviewed the current Strategic Plan (21001-2006), and outlined the Agency's performance against the Plan's targets. He described the process and time-scale surrounding development of the new draft Strategic Plan, and reviewed future possible influencing factors for the Agency, as identified by a horizon-scanning workshop.

Mechanisms for the Plan's delivery were also summarised. Key aims of the new Plan focussed on food safety, eating for health and choice. Members were informed that the Plan was currently out for public consultation, which ended on 25 June. The Agency had also met with stakeholders during the consultation period. The Agency's Board would re-consider the Strategic Plan in September, with anticipated publication in Autumn 2004.

6.2 In the ensuing discussion of the presentation, a number of comments were made, including:

  • a numerical target had not been set for continued further reduction of foodborne illness, as the Agency was working to develop a more sophisticated approach to measuring foodborne illness. This included monitoring the severity of illness, rather than just the number of cases.
  • prior approval of food premises would be discussed by the FSA Board later in the year.
  • views from the consultation exercise would be used to develop a model for enforcement. A new approach would consider issues arising from EU enlargement.
  • the Plan made no reference to non-UK sourced foods.
  • impact of globalisation of food processing and freedom of choice on achievability of food labelling.

6.3 The Chairman reminded the Committee that copies of the consultation package had been circulated to Members in April for comment by 25 June. Comments which had already been received by the Secretariat would be forwarded to the Agency. However, Members were able to submit any further comments by Wednesday 30 June. The Chairman thanked Mr Damon for his presentation.

7 Botulism in cattle (ACM/690)

7.1 At the Chairman's invitation, Ms Hoad (FSA) introduced paper ACM/690 on food chain issues linked to botulism in cattle.

7.2 Ms Hoad explained that from 1997-2002 an average of four botulism incidents linked to cattle occurred each year. This rose to 20 cases in 2003. The Veterinary Laboratories Agency (VLA) had written to the Veterinary Record highlighting the problem, and recommended several actions to reduce the risk of the disease. Ms Hoad described the symptoms which cattle with botulinum presented and explained the basis for clinical diagnosis of the disease. She commented that it was difficult to obtain positive confirmation of the disease as the concentration of toxin in the blood of affected cows was usually below the limit of detection.

7.3 Ms Hoad described sources of botulism in animals and summarised associated hazards in relation to entry into the food chain. Circumstantial evidence suggested that litter from deep litter broiler houses containing carcases of dead birds was the source of the disease in many of the recent outbreaks, the litter having been spread onto land on which cattle were grazing or on adjacent fields. The numbers of cattle involved was variable, involving anywhere between a single case to up to 80% of the herd. Cases have occurred in England and Wales and in Scotland and Northern Ireland. The Republic of Ireland and Northern Ireland were also reporting an increase in the number of suspected cases.

7.4 Procedures for management of risk, following a suspected outbreak were outlined. Members were informed that the Food Standards Agency was adopting a precautionary approach to protect the food chain. Following identification of an outbreak, milk and meat from affected herds were not allowed to enter the food chain for a period of 14 days from the last clinical case or 17 days from removal of the source of contamination.

7.5 In summing up, Ms Hoad explained the Agency sought the Committee's views on the food chain issues linked to botulism or suspected botulism in cattle.

7.6 Among the points made in the discussion of the paper were that:

  • there was an assumption that the strains of botulism types C and D were not active in humans. As the route of transmission had not fully been identified, there could be a risk that types C and D were active at some level in humans. Citing that there had not been any recorded cases in humans was insufficient evidence that humans could not succumb to these strains.
  • mouse bioassay tests in Northern Ireland indicated that the toxins could be found in blood, therefore there was a risk such toxins may also be present in milk although below the limit of detection. The LD50 of the toxin should be taken into consideration.
  • Members questioned the susceptibility of cattle, relative to mice and primates and whether there had been any recorded cases in humans from this source in developing countries.
  • poultry litter used as a fertiliser should be deep ploughed to reduce exposure to spores or toxin.
  • the spreading of poultry litter containing carcases or parts of carcases was an offence, and that Officers of Defra were under an obligation to report evidence of such cases.
  • there was a need to clarify the relative risk of botulinum in cattle from the spreading of poultry litter on land; The increase in environmental load of spores from this practice and the consequences of ingestion of both the C. botulinum spores and pre-formed toxin. There was some uncertainly regarding the natural history and epidemiology of C. botulinum in cattle. In particular, whether disease was always due to pre-formed toxin or whether it could arise from ingested spores. Further work was required in this area.
  • with regard to suspected outbreaks, the voluntary restriction of non-movement of cattle was well adhered to. Measures in place were found to be effective.
  • 7.7 The Chairman thanked Ms Hoad for her presentation. He explained that the Committee had raised several issues, which at the current time could not be answered. Therefore he proposed that an ad hoc group to explore these issues should be set up. The Chairman informed Members he would work with the Secretariat to identify potential membership, and requested that the group update the full Committee on its progress in December. The remit of the ad hoc group would be to address the implications of spreading poultry litter in terms of the risk to human health. Levels of toxin and its occurrence in blood and in milk after processing would be considered within this remit.
    Action : Secretariat

    8 Committee sub-groups (ACM/696)

    8.1 The Chairman invited the Chairs of each ad hoc and working group to provide a brief summary of progress. An information paper (ACM/696) had been provided detailing the terms of reference and the membership of each group.

    Ad Hoc Group on Infant Botulism

    8.2 At the Chairman's invitation, Dr O'Brien provided an overview of the epidemiology of infant botulism in the UK. Environmental sources and incidence of infection were also outlined. In the USA, Japan, Argentina and Italy, some cases had been linked to honey. 90% of world-wide reported cases occurred in the USA, with an average of 3 cases per 100,000 births. Since 1978, six UK confirmed cases of infant botulism had been reported. The most recent case occurred in 2001. All of these cases occurred in infants less than 6 months of age. Four cases were linked to type B toxin, one case was linked to type A toxin and a further case was linked to B and F toxins.

    8.3 Dr O'Brien outlined the terms of reference of the group. She said that the Group had met three times to date, twice since the ACMSF meeting in March. The Group had received presentations from three highly diverse infant food manufacturing companies, which included information relating to the product development, processing and food safety systems in operation. An expert on infant botulism provided information on the clinical and diagnostic epidemiology of C.botulinum. The Group was currently examining the advice to new manufacturers including the advice provided by Local Authorities.

    A literature review was in progress to revisit published evidence examining the relationship between infant botulism and Sudden Infant Death Syndrome. A further meeting was scheduled to take place in September, to assess evidence provided by independent food manufacturing experts and some of the Environmental Health Officers currently providing advice to weaning food manufacturers. Any advice presented to the ACMSF would also need to take account of the home-production of chilled and frozen baby foods.

    8.4 Ms Lewis commented that the remit of the Group could be widened to include dried rice and infant formula. The Chairman suggested examining whether any additional input was required by the Group when Dr O'Brien presented the outcome of the Group's work to the full Committee.
    Ad Hoc Group on Sewage Sludge

    8.5 At the Chairman's invitation, in the absence of a current Chair for the Ad Hoc Group on Sewage Sludge, due to the end of Dr Tim Wyatt's term of office, Mr Kyriakides provided a brief oral summary of the work of the Group's work.

    8.6 Mr Kyriakides reported that the Group had not met since it last reported to the Committee. Historically, the Group was convened to peer review the microbiological risk assessment of the disposal of sewage sludge via spreading on agricultural land. Comments and suggested wording on the UKWIR Report on pathogens in biosolids (microbiological risk assessment) had been provided by the Group. Two further risk assessments were considered by the Group, relating to catering waste (for Defra); and animal manure and abattoir waste (for the Food Standards Agency).

    8.7 Dr Hilton commented that she understood that comments from the Group on animal manure were being fed into Agency guidance, which was currently being finalised. She was under the impression that the Agency would not be responding formally back to the Group on these comments. The Secretariat agreed to check whether there were any outstanding issues for this Group.
    Action : Secretariat

    Imported Foods

    8.8 At the Chairman's invitation, Ms Davies explained that the Ad Hoc Group on Imported Foods was set up as one of three horizon scanning ad hoc groups, which the ACMSF agreed should report over a short period. The Group had not met since reporting to the full ACMSF in December 2003. The Group considered that further work was required in the areas of microbiological safety of food of non-animal origin entering the UK market; role of traceability systems; and formation of a systematic approach to monitoring information on foodborne disease in different countries. The Group also agreed the ACMSF should keep a watching brief on illegal imports.

    8.9 Ms Davies announced to the Committee, that due to other commitments, she wished to step down as Chair to this Group. The Chairman explained that some work remained which required further consideration. He informed Members he would discuss mechanisms for taking this work forward and identification of a new Chair for this Group, with the Secretariat.
    Action : Chairman and Secretariat

    Newly-emerging pathogens

    8.10 At the Chairman's invitation, Professor Hunter explained that one meeting of this Group had taken place. Groups already existed in the UK and in Europe to look at the issue of newly-emerging pathogens. Therefore a virtual Group had been set up to provide immediate advice on any emerging developments. An electronic message board facilitated discussion of issues without the need to formally convene.

    8.11 Professor Hunter explained that the message board was almost ready for use. An outstanding issue relating to the message board rules had now been resolved. However, some responses from Members confirming that they were content with the resolution of this issue were still outstanding. Mr Gayford asked if he could act as an assessor for Defra on this Group. Other members also indicated an interest in having access to the board.

    8.12 The Chairman agreed that the Committee should audit the outcome of the message board over the next 12 months. Professor Hunter indicated that he was content for Members, other than those of the Ad Hoc Group to have access to the board. Mr Kyriakides suggested that members of the Group who had not indicated their consent to sign up to the message board rules, should write to the Secretariat by 1 July. Other Members of the Committee who wished to have access should also inform the Secretariat of this.
    Action : Members and Secretariat

    8.13 Dr Hilton informed Members that there was some outstanding business between the Food Standards Agency and the Health Protection Agency (HPA) relating to how to assess zoonotic risk, as an agreed forum for discussing food issues within a set timeframe was lacking. The Food Standards Agency had written to the HPA with regard to this issue.

    Surveillance Working Group

    8.14 In Professor Humphrey's absence, the Chairman read out the statement provided by Professor Humphrey summarising the work of the Surveillance Working Group. The Group was set up to provide the Food Standards Agency with advice on the structure of surveys, methods used and interpretation of results. It also played a role in identifying potential contractors. To date the Group had been involved in the retail chicken survey, the survey of UK produced eggs and the planned survey of imported eggs.

    8.15 The Chairman thanked all the Chairs for their contributions. He informed the Committee that a review of the ad hoc and working Groups would become a standing agenda item at future ACMSF meetings.
    Action : Secretariat

    9 Undiagnosed encephalitis in ruminants

    9.1 At the Chairman's invitation, Dr Brown updated the ACMSF on a recent human health risk assessment carried out by an Expert Group chaired by the HPA, of which he was a member. He explained that this Group was convened following a case of polioencephalitis in a heifer, which had recently received coverage in the press.

    9.2 Dr Brown informed the Committee that, at the meeting held on 21 June, experts reviewed information about the original case in a heifer, another related case in a bull and 20 cases in sheep, which had occurred over a 10-year period. He added that the disease was diagnosed through the appearance of brain lesions. Recent laboratory investigations from the original case in a heifer identified an enterovirus as the most likely cause of infection, which the Group concluded was unlikely to pose a threat to human health.

    Enteroviruses did not usually cross between species, and none of the affected animals had entered the food chain. Further, if an affected animal did manage to enter the food chain, cooking or pasteurisation would inactivate enteroviruses. Further investigations were needed to collate all the clinical and pathological findings, as the virus had only been identified in one case to date and therefore it was difficult to complete a full risk assessment. Further work was also required to examine the clinical and pathological differences between the cattle and the sheep cases.

    9.3 Mr Gayford, who was also present at the risk assessment meeting, added that the Expert Group had been informed of another 7 cattle cases, with similar neuropathological changes which had been submitted under BSE Orders between 2000 and 2003 and were negative for BSE.

    9.4 In the ensuing discussion, a number of comments were made, including:

    • what proportion of non-BSE suspected cases were further investigated. Mr Gayford advised Members that this was not known. Members also queried whether additional cases had been identified as part of BSE investigations.
    • The route of transmission for viruses causing encephalitis was complex including faecal-oral or through vectors such as ticks or mosquitoes. Dr Brown informed the Committee that it was clear from the clinical data that there was more than one cause of this illness as cattle and sheep each had their own species-specific viruses that caused encephalitis.

    9.5 The Chairman reminded Members that the remit of the ACMSF was to assess the risk of the disease to the food chain. In summing up, he explained that, at the present time, the data so far represented incomplete investigation and knowledge of a collection of cases of encephalitis and encephalomyelitis in two different species, and that these were likely to be due to a range of viruses. The existing HPA expert risk assessment group was best placed to continue evaluation of the risk to human health, including risks through the food chain. Dr Brown agreed to keep the Committee fully briefed on developments in this area as they arose. The Chairman thanked Dr Brown for his report.
    Action : Dr Brown and Secretariat

    10 Chronic sequelae of foodborne infections

    10.1 At the Chairman's invitation, Dr O'Brien explained that the original aim of this work was to derive an estimate for the severity of chronic sequelae as a result of foodborne illness. However, this was proving difficult due to the limited nature of the information available in the literature. This had arisen because of a lack of standard case definitions of chronic sequelae, variable periods of follow-up, poor response rates and a bias towards patients with severe symptoms. There was also a lack of good demographic and microbiological data. She added that where data was available, it appeared that between 6 and 30% of foodborne cases developed chronic sequelae, depending on case definitions and length of follow-up.

    She highlighted two studies, one from Sweden and a study emanating from the infectious intestinal diseases study in England. Professor Hunter added that there was a third study to be published in the Journal of Clinical Infectious Disease, which would be available in August. Professor Hunter also declared that he may have a conflict of interest in relation to this item resulting from his involvement in legal cases involving people who became ill whilst travelling abroad.

    10.2 The Chairman concluded that this work had shown that it was difficult to quantify the information available and therefore to derive an estimate for the severity of chronic sequelae. He thanked Dr O'Brien for her report.

    11 Dates of future meetings

    11.1 The Chairman brought to Members' attention paper ACM/692 which listed the dates for further ACMSF meetings in 2004 and the dates for the meetings in 2005.

    12 Any other business

    12.1 The Chairman informed the Committee that the Second Report on Campylobacter had been published for consultation on 19 May, and that a copy of the consultation package had been circulated to members. Any Members who wished to comment as private individuals were welcome to submit their comments to the Secretariat by 13 August. If necessary, following the close of the consultation period, the Campylobacter Working Group would be re-convened to consider the responses. Any amendments to the Report would be presented to the September ACMSF meeting for adoption.

    12.2 The Chairman reminded Members that the consultation on the Guidance on the safety and shelf-life of vacuum and modified atmosphere packed chilled foods with respect to psychrotophic C. botulinum had also been circulated in May. Comments should be submitted to the Secretariat.

    12.3 Mr Kyriakides enquired of Members whether there was any information available on the microbiological safety controls for comminuted meat products such as doner kebabs. Mr Mepham said that surveys carried out by Local Authorities on doner kebabs had not indicated any microbiological problems associated with these products. Mr Kyriakides commented that possibly those with a cultural knowledge of the handling of this traditional product would be able to avoid hazards, whilst others might not be aware of the traditional practices that maintained food safety. Mr Bassett added that he was aware that there had been some cases of foodborne illness related to doner kebabs in New Zealand.

    The Chairman requested that the Food Standards Agency provide a briefing paper outlining the processes used in preparing these products for consumption, and risks to human health. Dr Hilton commented that in the UK, the most recent outbreaks associated with kebab shops had been associated with the lettuce rather than the meat. Members were requested to forward any relevant information to the Secretariat.
    Action: Secretariat

    12.4 Ms Lewis requested that the ACMSF receive an update on developments relating to E. coli-related foodborne disease, in particular with regards to the position of organic foods. The Chairman declared an interest as he had chaired the E. coli Task Force. He asked the Food Standards Agency to prepare a briefing paper updating Members on implementation of the Task Force's recommendations. He added that the Scottish Executive had written a report on the recommendations of the Task Force and he understood that the HPA had some data on organic foods which may be of relevance.
    Action : Secretariat

    12.5 Mr Piccaver made an observation that the information paper on the results of the LACORS/HPA study of external packaging of raw meat and offal from retail premises (ACM/693) made no mention of where the packaging for these products had been stored. The Chairman requested that the Secretariat clarify this point with the HPA.
    Action : Secretariat

    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 statements.

    13.2 Mr Long (VEGA Research) commented that the public had difficulty in hearing the meeting. The Chairman agreed to explore options to improve the sound quality for the next meeting.
    Action : Secretariat

    13.3 Mr Long commented that the BSE Inquiry had examined various animal products fed to dairy cows, including dried poultry manure. He wasn't sure whether dried poultry manure and broiler litter was permitted to be fed to cows as a result of the BSE regulations. He registered his surprise that farmers were permitted to spread these substances on the land. He also asked if there was any evidence linking botulism to badgers. He queried the setting and evaluation of the Food Standards Agency's target of a 20% reduction in foodborne illness by 2006. He also highlighted terrorism in relation to micro-organisms.

    13.4 Mr Gayford confirmed that dried poultry manure and broiler litter were not allowed to be fed to ruminants. Published Defra information advised that poultry litter should not be used as fertiliser on grazing land. It should be disposed of by either incineration, deep ploughing or burial.

    13.5 Mr McMullin commented that botulism had been identified in wildlife as a natural phenomenon, mainly in wildfowl. He was unaware of any reports of badgers succumbing to botulism.

    13.6 Dr Hilton explained that in 2001 when the 20% reduction for foodborne illness had been set, this was considered a reasonable target to set. However the Agency was currently considering more sophisticated ways of measuring the impact of foodborne disease, taking account also of its severity.

    13.7 The Chairman advised that the subject of terrorism and microbiology fell outside the Committee's remit.

    13.8 Dr Lund commented that cases of type C botulism had been reported in Germany, the Netherlands and the USA. She added that type B botulism was rare in cattle, but known to affect humans and horses. Type A botulism had been attributed to mascapone cheese (via milk). She added that more information relating to type C botulism was required.

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