ACMSF minutes: 25 March 2010

Meeting held in Aviation House, 125 Kingsway, London WC2B 6NH

Present

Chair:
Prof S O’Brien

Members:
Dr D Brown
Mrs V Buller
Prof J Coia
Mrs R Glazebrook
Dr R Holliman
Prof T Humphrey
Prof P Hunter
Mr A Kyriakides
Dr S Millership

Assessors:
Ms L Redmond (FSA)
Mr S Wyllie (Defra)

Officials in Attendance:
Mr David Alexander (FSA)
Dr Joanne Aish (FSA)
Miss Louise Knowles (FSA)
Miss Robyn Ackerman (FSA)

Secretariat:
Ms G Hoad (Scientific Secretary)
Dr D Cutts (Administrative Secretary)
Mr A Adeoye
Ms S Butler

Invited experts and contractors:
Dr David Tompkins (WRAP)
Dr Paul Gale (VLA)
Dr Phillip Longhurst (Cranfield University)
Dr Iain Gillespie (HPA)
Dr Piers Mook (HPA)
Dr Ricardo de la Rua-Domenech (Defra)
Mr Jose Gomez-Luengo ( Meat Hygiene Service)
Dr Dean Burfoot (Campden BRI)
Dr Linda Everis (Campden BRI)

Others:
Sally Barber , British Retail Consortium
Roy Betts, Campden BRI
Fiona Brookes, Northern Foods
Keneth Chinyama, Food and Drink Federation
Bridgette Clarke, Bakkavor
Jane Duddle, Waitrose
Jenny Hopwood, Marks & Spencer
Intisar Khan, Dairy Crest
Samantha Kirk, Tesco Stores
Barbara Lund, IFR
Tom Miller, National Consumer Federation
Heather Paine, Chilled Food Association
Rick Pendrous, Food Manufacture Magazine
David Robinson
Michael Wood, Norpath Scientific

1. Chair’s Introduction

1.1 The Chair welcomed ACMSF Members and members of the public to the 72nd meeting of the Committee. The Chair introduced Ms Geraldine Hoad who was standing in for Dr Paul Cook as Scientific Secretary and Dr Darren Cutts who was standing in as Administrative Secretary. She also welcomed Mr David Alexander (FSA), Dr David Tompkins (WRAP), Dr Paul Gale (VLA), Dr Phillip Longhurst (Cranfield University) who would be presenting agenda item 6 , Miss Louise Knowles (FSA), who would be introducing agenda item 8, Dr Iain Gilliepie and Dr Piers Mook (HPA) who would be presenting agenda item 9a, Miss Robyn Ackerman (FSA) who will be presenting agenda item 9b, Dr Ricardo de la Rua-Domenech (Defra) and Mr Jose Gomez-Luengo (Meat Hygiene Service) who would assist in presenting agenda item 10, Dr Joanne Aish (FSA), Dr Dean Burfoot and Dr Linda Everis (Campden BRI) who would be presenting agenda item 11.

2. Apologies for absence

2.1 Apologies for absence had been received from Mr J Bassett, Mr P McMullin, Dr Paul Cook, Mrs Jenny Morris and Prof Peter Williams.

3. Declarations of interest

3.1 The Chair reminded Members of the need to declare any conflicts of interest relating to items on the agenda, both at the beginning of the meeting and subsequently if the need arose during discussions. Prof Coia declared he provided consultancy advice to Tesco. Prof O’Brien declared an interest as she was involved in work to be discussed under agenda item 9a.

4. Minutes of the 71st meeting

4.1 Members approved ACM/MIN/71 as a correct record of the previous meeting.

5. Matters arising

5.1 The Secretariat had produced a summary of action taken on matters arising from previous meetings (ACM/975). The Chair stated that it would be beneficial to revisit the paper on Openness at the December ACMSF meeting to consider the Secretariat’s investigation into the practicalities of making subgroup meetings open.

6. Waste and Resources Action Programme (WRAP): Risk assessments on the use of source segregated composts in agriculture

6.1 Members were reminded that the Committee had previously given consideration to this item at the September 2009 ACMSF meeting. David Alexander (FSA) requested that the Committee assessed the risk assessments, presented and carried out under the WRAP Confidence in Compost Programme, in terms of microbiological food safety. The risk assessments considered the use of composting and biogas treatment to dispose of waste containing meat and the use of source-segregated composts in UK agriculture.

6.2 Dr David Tomkins (WRAP) gave an introduction on WRAP describing the company as a “not for profit” organisation, backed by government funding, that helps stakeholders reduce waste by the development of sustainable products. It was highlighted that over 2.5 million tonnes of compost were produced in the UK each year with approximately 1 million tonnes made from feedstocks that did not include waste food. Approximately ¼ million tonnes was made from feedstocks that did include some waste food with the majority used for arable crops. It was added that the compost industry was heavily regulated with 55% of the industry either compliant or working towards attaining BSI PAS100 specification for composted materials. To provide reassurance that the assumptions used in a 2002 catering waste risk assessments were still valid three different risk assessments had been performed. They covered garden wastes, waste food and “other” wastes.

6.3 Dr Paul Gale (VLA) provided an update of the VLA’s 2002 risk assessment which estimated risks to grazing livestock from food-borne pathogens. Exotic viruses, endemic bacteria, spore-forming bacteria, protozoa, avian influenza virus, MRSA, scrapie, porcine circoviruses and porcine parvoviruses were considered in the assessment. The model was updated to include data on illegally imported meat into GB, which was estimated to be 11,875 (4,398 - 28,626 CI) tonnes a year. These meats introduced risks from foot and mouth, classical swine fever, swine vesicular disease and African swine fever. Other key data included, a Campylobacter count in fresh chickens at retail of 85,000, a total E. coli O157 loading on sheep meat and beef of 1.2X1012 per year. The amount of raw meat discarded was judged to be 3.3% for poultry, 2.1% pig meat, 1.7% beef and 3.2% lamb. The amount of food waste produced in the UK was 6.7 million tonnes per year of which all was assumed to be composted. In general the updated risk assessment was considered more precautionary than that performed in 2002.

6.4 Results showed that due to composting one would expect to see one case of classical swine fever virus in pigs in 1528 years, one case of African swine fever virus in 102,491 years, one case of FMD in 1.7 million years and one case of swine vesicular disease virus in 47 million years. Therefore risks from exotic viruses from imported meat were low, and were reduced significantly by the composting process. For the faecal bacteria, salmonellas, E. coli O157 and campylobacters it was concluded that the risks to humans from faecal pathogens through the consumption of vegetable crops treated with food-waste compost was remote. Further, the risk to humans from C. botulinum spores on fresh vegetables from soil or compost-amended soil was also low due to spores being unlikely to germinate in aerobic composting conditions.

6.5 Dr Philip Longhurst (Cranfield University) presented data on a model that considered and prioritised combinations of source to pathway to receptor exposure risks. Waste scenarios included green waste, food waste and shellfish waste. Hazards included persistent toxic elements, phytotoxins, marine biotoxins and pathogens. Humans and animals were assumed to be exposed to these hazards through ready to eat crops, combinable crops, harvested forage and grazed forage. The model used the worst case scenario to ensure all were protected and assumed that the compost met the requirements of the PAS100 standards. An example of model use was provided for E. coli O157 highlighting parameters such as decay of the pathogen, uptake and transfer to crops, washing the crop, re-growth of pathogen during storage and the amount of pathogen to which an adult or child would be exposed. Results from the model showed that after screening all risk pathways, E. coli O157 was identified as the highest risk. However, the outcome was still very low in terms of risk with the result below that of a theoretical safe dose.

6.6 In the ensuing discussion the Committee considered that:

  • There appeared to be an emphasis on modelling bacteria that would naturally be killed by composting rather than the more resistant forms of pathogen such as spores. Dr Gale added that the model did look at botulism and TSEs as potential issues and it was suggested that Clostridium spp. could be considered but noted that looking at one thermo resistant spore did give a feel for what would happen with other similar pathogens.
  • Clarification was required regarding the by-pass route in the composting process for the two models presented. There appeared to be a by-pass route for segregated waste stream but not for the others. Further, for the Cranfield Model it was not clear why 1000 cfu/g was used for E. coli in the study as a worst case scenario. In response, Dr Gale stated that the models were looking at different scenarios and were trying to answer different questions hence the different by-pass routes. Dr Longhurst added that the Cranfield Model assessed a compost product at the PAS100 standard and therefore used the standards required for that product. By-pass would have already taken place and would not affect the output of the model.
  • The models did not appear to consider a worst case scenario as suggested, with models primarily looking at animal health rather than human. In response Mr Steve Wyllie (Defra) informed Members that the remit of the research project was to focus on issues which were of high importance at that time, mainly exotic animal diseases such as FMD. Further, there was a need to consider a wider range of pathogens such as Hepatitis-E in pig waste and Cryptosporidium spp. and Giardia spp. from cattle. Assumptions used regarding the washing of vegetables were also not correct. For example, lettuce may be sold whole rather than the “bagged” scenario used in the model. Moulds which were detrimental for immune-compromised patients were also not considered. A Member asked whether the views of consumers were considered in relation to the acceptability of food waste being used as compost. This was particularly relevant if compost derived from meat was used on food crops. Dr Longhurst explained that although such a study did not form part of this work, studies had been performed and were available separately.

6.7 In summing up the Chair noted that the papers for the item were substantial with a large number of questions raised. Given the short notice between circulating the papers and the meeting taking place, it was proposed that the risk assessments be considered by selected Members outside of the meeting who would then report back at a future meeting. It was agreed that Mr Kyriakides, Mr Bassett, Prof Coia, Dr Holliman, Prof Hunter and Mrs Buller would give further consideration to the documents.

Action: Members named above/Secretariat

7. Listeria monocytogenes

(a) Redefining the population at risk

7.1 Dr Iain Gillespie (HPA) presented an update on the incidence of listeriosis in England and Wales. Non-pregnancy related incidence of listeriosis was shown to have increased since 2001 in those over 60 who present with bacteraemia in the absence of CNS infection. The increase could not be explained by variables such as gender, regional differences, recognised outbreaks, emerging L. monocytogenes subtypes, underlying conditions or socioeconomics. There were no differences observed between bacteraemia and CNS cases of listeriosis in terms of gender, season or infection subtype. However, underlying conditions were shown to be a factor. Malignancy in digestive organs was linked with bacteraemia and alcohol-related conditions were more likely to be related to CNS cases. Risks of listeriosis in relation to co-morbidity were presented showing that higher risks were associated with neoplasms, in particular cancers of the eye, brain, CNS and lymphoid tissues. Endocrine, nutritional and metabolic diseases, circulatory system and musculoskeletal system diseases were also associated with high risks. Incidence of listeriosis was also found to be higher in those most deprived. Of these cases, most were associated with a particular national chain of convenience store and the use of local food retailers. With increasing deprivation it was shown that cases were more likely to be in non-white British groups who were more likely not to eat outside of the home.

7.2 Cases of L. monocytogenes in the over 60s were investigated showing that those infected were more likely to eat cold cooked beef, processed pork, cold cook seafood and dairy products. They were less likely to consume other types of pork and seafood, sandwiches and fresh vegetables. For pregnancy associated disease, although there was no observable change over time in non-ethnic groups, since 2005 there had been an increase in listeriosis in those considered of ethnic minority origin on the basis of surname. These people were considered more likely to consume pate, cabbage or dill and shop in local food retailers. Dr Gillespie concluded that current UK food safety advice was delivered passively and targeted preferentially to pregnant women. This research was said to show a clear need to actively target advice to a wider range of vulnerable groups.

7.3 In the ensuing discussion the Committee noted that:

  • There was evidence that some of those people described as ethnic minorities had come to the UK to give birth but had been exposed to listeriosis outside of the UK and that this should be given consideration in the future. Dr Gillespie responded that most cases described in the review were found to be resident in the UK. However, as the incubation period was approximately 90 days it was difficult to identify the source of infection. In addition neither ethnic-minority groups nor non-ethnic minority groups were more likely to eat foods brought in from overseas which may be considered a risk.
  • It was unclear whether the behaviours described in the non-pregnant cases were age specific and what the total number of associations considered was in addition to those presented. Dr Gillespie stated that, although desirable, the remit of the project did not allow for detailed analysis of age related associations other than those over and under 60 years of age. Regarding exposure associations, approximately 40 were considered which were consolidated from a larger data set which again was limited by the terms of the project. Clarification was also requested as to whether the risks associated with supermarket chains had been the same chains for all cases. In response it was noted that there was a strong association with one major supermarket chain with links to food purchasing habits and deprivation. However, it was important to note that data were not available to investigate the results further.
  • Although risk management, rather than advising people generally, it was likely to be more beneficial to advise those with underlying conditions of the factors that would make them more susceptible to listeriosis although it was acknowledged that more research was needed to identify specific risks associated with certain conditions. In general there was a consensus that advice should be targeted. Finally it was asked whether there was a way of using the association data obtained in the study to determine causation. It was stated that this work went beyond the scope of this project. However, this would be discussed during the presentation by the FSA’s Social Science Research Committee.

(b) Report of the Social Science Research Committee (SSRC) Working group

7.4 Miss Robyn Ackerman (FSA) introduced the paper on the SSRC working group assessment of L. monocytogenes and the food storage and food handling practices of the over 60s. The SSRC recommended that a thorough literature review on new research should be commissioned to aid the group in further deliberations. In addition it was recommended that a social survey be performed to provide accurate baseline data on knowledge of food safety and food handling in the over 60’s (option i), allowing follow up on specific groups of people (option ii). This would be a high priority should the FSA wish to consider the causes of future changes to listeriosis in the over 60s. Also recommended were a household based study of those over 60 who have had listeriosis to establish socio-demographic characteristics (option iii) and an exploration of dissemination of current advice (option iv), these would be a priority if considering current food related practices. Finally, there was a recommendation to develop a better understanding of the retail environment such as pack sizes (option v) although this was not considered a high priority.

7.5 Miss Ackerman added that a number of questions in connection with food safety behaviours had been added to the FSA’s Food Issue Survey (FIS), which investigates approximately 3000 adults measuring attitudes, knowledge and behaviours on food issues. The first results from the FIS are expected at the end of 2010. Further to this the FSA’s Social Science Research Unit was developing a study to investigate food safety behaviours in the home which would focus on vulnerable groups. This was expected to report in October 2010. The Committee was asked to consider what they believed the priorities for the Agency were in terms of the recommendations provided by the SSRC and whether it was appropriate to use the recommendations in the planning and prioritisation of FSA research.

7.6 A Member opened discussion stating that there were two risks to consider in this assessment, firstly the risks associated with behaviours and the other the underlying vulnerabilities. Behaviours were considered to be the primary factor to investigate and Members agreed that options (i) and (ii) would be a priority in terms of determining exposure routes. Members also considered that along with identifying exposure routes, it was also important to find a way of connecting to the group the advice is aimed at, option (iv). There was also a need to further define the population at risk, obtaining data to refine associations would help target those at risk.

7.7 Members considered that option (v) was also important as exposure to listeriosis from supermarket products had been highlighted and as such there was an argument to examine particular foodstuffs for Listeria, particularly those that are stored after opening. A Member asked whether the FIS picked up shopping trends with age and possible changing habits. Miss Ackerman responded that some data were included in the survey, for example, how people shop, the use of a shopping lists, frequency of shopping. However, there was flexibility in the survey to accommodate further questions if necessary.

7.8 In summary it was agreed that the Committee required more data to inform and assess the high risk associations before any advice could be developed. For example, the current data did not allow for those cases of listeriosis in the over 60s to be linked to specific exposure routes. It was agreed that there was not enough evidence which would alter the advice provided by the FSA website. However it would be beneficial to ensure that the CMOs are aware of the issues and that health professionals were informed.

8. ACMSF Subgroups

8.1 Prof Tom Humphrey, Chair of the Ad Hoc Group on Vulnerable Groups (AGVG) and the Surveillance Working Group (SWG) reported that the AGVG had met in December 2009 and the SWG in March 2010. The AGVG discussed a position paper on Toxoplasmosis in food which will be further discussed at a meeting in May 2010. This paper will be presented to the ACMSF later in the year. The SWG considered a UK wide survey on the microbiological contamination of fresh red meats and a UK wide survey on ready to cook meats and pate at retail. Both surveys have been signed off by the group and the FSA plans to publish the reports later this year. The group has also put together a paper on isolating Campylobacter in food which will be presented to the ACMSF at a future meeting.

9. FSA/BBSRC/Defra Campylobacter Workshop

9.1 Ms Gerry Hoad (FSA) presented a report on the joint FSA/Defra/BBSRC Campylobacter workshop that had taken place in October 2009. Four sessions were held at the meeting entitled, understanding the organism, Campylobacter in poultry, the farm and slaughter house environment and Campylobacter in humans. The priorities highlighted at the workshop included the development of an increased understanding of Campylobacter in real life and possible interventions, an understanding of Campylobacter from bacterium to the bird to human, a focus on routes to reduce levels of Campylobacter in chicken and the development of on farm tests. A five year strategy document will be produced as a result of the output of the meeting. This will highlight the priorities for research and will be published by the FSA in April 2010 and will aid the FSA in working towards having a Campylobacter risk management programme.

10. Foodborne viral infections

10.1 Miss Louise Knowles introduced the item reminding members that ACMSF set up a working group on Foodborne Viral Infections which published a report in 1998 on the sources of transmission of foodborne illnesses and prevention and control measures. The ACMSF reviewed the item again in 2007 in response to new developments and outbreaks of foodborne viral infections. Members were also informed that results from the Second Infectious Intestinal Disease (IID2) study would be available later in 2010.

10.2 Dr David Brown gave a presentation on the key developments in foodborne viruses over the last ten years stating that since the last ACMSF review in 1998, risk assessments had been carried out into Norovirus (2004) and Influenza A and Hepatitis E (2007–2008). Viruses were highlighted as being much simpler organisms than bacteria with important differences in epidemiology as they could only replicate in the cells of the host species. Viruses also tended to be highly infectious with typically 1 to 100 infectious particles required for infection. Hepatitis and Norovirus were described as causing the greatest burden of viral foodborne disease in the UK with Norovirus observed throughout the age groups. It was estimated that there were 100,000 incidences of foodborne viruses per year of which 70% were link to Norovirus. Five phylogenetic Norovirus groups had been identified with 22 genotypes. With reference to human susceptibility and resistance to Norovirus, secretor status was determined to be a factor with those with secretor negative status not susceptible to Norovirus. Norovirus also had the ability to persist in the human population by two mechanisms, receptor switching and antigenic variation. The role of Norovirus typing in disease outbreaks was described highlighting that cases from food handlers had been linked food consumers. However, problems occurred when multiple Norovirus genotypes were identified in an outbreak such as from produce affected by sewage.

10.3 The Committee was informed that most occurrences of indigenous Hepatitis E infection in England and Wales appeared in elderly males, peaking at around 70 years with strains predominantly from Genotype 3. There were currently seroprevalence studies underway to determine the true incidence and burden of infection in the UK. However, it was suggested that there could be as many as 65,000 unidentified cases in the UK. In summary, Dr Brown concluded that priority areas for risk management were Norovirus and Hepititis A in bivalve molluscs, fresh fruit and food preparation. More data were required on quantification such as the prevalence, infectious doses in food and contamination route.

10.4 Opening the discussion a Member stated that the data reported on viruses appeared to be from outbreaks and it would be beneficial to have surveillance to look at other foods which may be missed as a potential risk as small outbreaks may go unreported. The Chair added that in light of the information presented it would be beneficial to hold a review of foodborne viral infections. In response a member noted that the IID2 results would be reported later in 2010 and that it would be useful to convene the group after this data was published. Additionally it was felt that any review should consider that for enteric viruses, it was hard to distinguish between foodborne infection and infection from other routes. Focusing on foodborne infections may miss the bigger picture as non-foodborne infection was likely to occur more and would impact heavily on the observable epidemiology.

10.5 The Chair concluded that a subgroup would be formed to review foodborne viral infections and Dr David Brown was invited to Chair the group. Mr Kyriakides also agreed to be a member. Committee members who wished to form part of the subgroup were asked to contact the secretariat. It was considered important that food remained the foremost issue for discussion by the subgroup as this was the remit of the ACMSF. However, it was important to ensure that the Terms of Reference covered all aspects which impacted on food. The Terms of Reference of the subgroup would be agreed by the ACMSF at a future meeting.

Action: Secretariat/Members

11. Biltong

11.1 Dr Joanne Aish (FSA) introduced the item stating that due to a number of incidents involving the production of biltong in the UK the FSA felt that more information was required on the microbiological hazards in order to provide manufacturers and local authorities with practical advice on safe manufacturing practices. Campden BRI was commissioned to perform a literature review of available data on biltong plus similar dried products, and in particular jerky.

11.2 Dr Dean Burfoot (Campden BRI) gave an overview of the available literature on biltong and jerky. Biltong was described as being an uncooked, marinated (acid and salt), low temperature air dried product formed from strips of meat. The product was typically marinated for 18 to 24 hours at 4oC and dried at 35oC at 30% humidity for 6 days. Final product had a moisture content of between 20 to 30%. Biltong was described as being microbiologically stable when it had a water activity below 0.7aw with a linear relationship observed between moisture content and added salt for microbiological stability. Typically the product had a 6% salt content and 25% moisture content. Production of Jerky was shown to follow a similar process. However, reformed meat was used which was heated, effectively cooking the product before drying. Recommendations from USDA required that the meat was heated to 71oC in moist heat or marinade and dried to 0.85 aw. If 71oC could not be guaranteed, post-dry heat was the required at 135oC for 10 minutes.

11.3 Dr Linda Everis (Campden BRI) described the microbiology of biltong and highlighted typical cfu values for viruses, bacteria, yeast and moulds. Research was reviewed that demonstrated that the effect of different production factors such as salting, marinating, drying and temperature were not inhibitory to certain pathogens, however, in combination they were found to be by the hurdle effect. Reduction in pathogens in processing (marinating and drying) was shown in Salmonella (2 to 3 log), E. coli (2 to 3 log), L. monocytogenes (2 to 4.5 log) and S. aureus (1 to 6 log). Reduction increased further with a drier product. Certain pathogens were also shown to have long survival times in biltong with S. Newport lasting for up to 24 months, S. Dublin 6 months and S. aureus 64 days. For jerky only two surveys were reported with neither showing the presence of E. coli O157 or S. aureus but Salmonella was found in 0.3% samples and Listeria in 0.5% of samples. Again, marinating and drying were effective in reducing pathogens. Research showed that when the processes described by the USDA were followed, Salmonella, E. coli and L. monocytogenes were not observed in the final product.

11.4 Mr Burfoot concluded that there was currently no legal definition of, or specific production guidance, for biltong although there was a range of guidance on jerky mainly from the US and New Zealand and a prescriptive definition from the USDA.

11.5 Responding to the comment that there was no legal definition for biltong a Member noted that biltong would still fall under the normal UK food safety requirements in terms of enteric pathogens. It was highlighted that there were other similar products which do not have a designed standard, such as salami and Parma ham, so it was important not to demonise biltong when it may have similar risks to those which are more widely known. It was also highlighted that major producers were more likely to have a product quality management process such as a HACCP plan whereas the greatest concern would be with the small producers who do not have such plans.

11.6 A Member asked whether the biltong product re-absorbed moisture after the drying process. Mr Burfoot responded that there was no literature on this. However, work at Campden had found that storing the product in different environments did affect the distribution of moisture throughout the product. This suggested the need to provide advice on the packaging for the storage of the product and the time for which it should be consumed after opening.

11.7 Members agreed that the documents provided information for the FSA to write advice and guidance on the production of jerky. However, there was no similar evidence provided for the safe production of biltong. The protocols also described in the documents were particular to the South African environment and were therefore not directly applicable to the UK. The Chair summarised that there was currently insufficient evidence for the FSA to provide advice to food producers and local authorities on the production of biltong. More experimental evidence was required on the effect of processing techniques before risks could be assessed. There was also a need for clarification on outbreaks said to be associated with biltong to ensure that the epidemiology about the source of infection was accurately modelled and source identified.

12. M.bovis: possible health risks from meat and milk

12.1 Ms Hoad introduced the item stating that the Committee had previously assessed the health risks to consumers of meat from animals with evidence of M. bovis infection in 2001 and 2003. Those assessments focussed on the risks to human health from meat and concluded that the risk, if any, from the consumption of meat was very low. In 2002 ACMSF also considered that there were no concerns in relation to milk and dairy products as legislation and controls adequately covered exposure pathways at that time. In October 2009 the FSA Board requested that the Agency review potential risk to consumers from meat and dairy products from cattle with evidence of M. bovis infection as a result of an increased occurrence of M. bovis in the UK cattle population. The Board requires reassurance that current control measures are adequate to protect human health.

12.2 It was highlighted that the number of human M. bovis infections per year averages around 30 cases with the trend being stable with a slight decline since 1994. Most human cases are in those born before 1960 suggesting a reactivation of an old infection. The HPA considered that given the small number of human cases, there was no evidence for the bovine epidemic spilling over into the human population. Members were informed that active on farm bovine TB testing was supplemented by routine meat inspection of non-reactor cattle at commercial slaughter and a series of new control measures introduced in 2004 (EC Reg 854/2004) which covered both ante-mortem and post-mortem inspection. Further to this a gamma interferon blood test for cattle was adopted in legislation in 2006 to enhance sensitivity of bovine TB testing.

12.3 The Committee was informed that regulation 853/2004 now requires that raw milk should come from animals belonging to a herd that is officially TB free (OTF). If OTF status was lost then milk from reactor cattle was not allowed to enter the food chain and milk from non-reactors had to be pasteurised. Additionally, for cattle in England and Wales producing raw milk for human consumption, Defra require that the herd is annually tested for TB. Scotland currently bans the sale of all raw drinking milk and cream. The FSA is currently funding a project expected to end in autumn 2010 which is investigating the survival of M. bovis in raw milk. As milk and dairy products had not been previously assessed in detail by the ACMSF, the Committee was asked whether it necessary to set up a working group to assess potential risks from milk or milk products.

12.4 A Member opened the discussion highlighting that most cases of TB in humans were currently from those born prior to 1960 and that cases were more likely in UK immigrants. Therefore, evidence for primary infection in the UK under current regulation and treatment of products was considered low. Members agreed adding that they were not clear what the FSA required of the Committee since there was no new evidence that would change the current assessment.

12.5 On regulatory changes, a Member asked what had happened to previous ACMSF advice on animals with visual lesions in lymph nodes not going into the food chain. Jose Gomez-Luengo (MHS) responded that the UK had now adopted EU controls to bring it into line with the rest of the EU and that although the UK legislation was implemented in 2006, the recommendation was actually taken forward from 2002. In addition, if an animal was a TB suspect, a more detailed study would be performed to ensure infected meat did not go into the food chain.

12.6 Regarding the risks from milk the Committee considered that the high level of pasteurisation of milk in the UK ensured that the risk of becoming infected with tuberculosis from milk remained low. Members added that the pasteurisation process been designed to protect against Mycobacterium bovis and as such it was difficult to see why milk was considered a risk. The Committee, which advises that raw milk should not be made available for public sale, saw no reason to change its existing position on raw milk. Members raised concern that there was a discrepancy in the advice in the different countries of the UK with some allowing and others banning the use of raw milk.

12.7 The Chair concluded that current evidence had not shown a need to change the existing risk assessment and so there was no need to establish a subgroup to examine further the risks from raw milk at this time as was suggested by the paper. However, further consideration could be given to this once results from the FSA project on cheese made from raw milk were known. These results are due towards the end of 2010.

13. Dates of Future Meetings

13.1 Members were reminded that the remaining ACMSF meetings for 2010 would be held on the: 3rd June 2010, 23rd September 2010 and 2nd December 2010. For 2011 meeting were timetabled for: 24th March 2011, 2nd June 2011, 22nd September 2011 and 1st December 2011.

14. AOB

14.1 There was no AOB.

15. Public Questions and Answers

15.1 No questions were raised by members of the public.