Volume 6: Human Health, 1989-96
8. Development of guidance on occupational risks from BSE and other TSEs
1988
Development of guidance on occupational risks after the emergence of BSE

Development of guidance on occupational risks after the emergence of BSE

8.26 During 1988 three sets of occupational guidance on BSE were produced: one set was aimed at handlers of BSE-affected cattle and the other two were issued by the CVL for internal use.

Concern for handlers and HSE guidance

8.27 During early 1988, HSE Agricultural Inspectorate was alerted to the risks to hauliers of attacks from BSE-affected cattle. In March 1988, Mr A M Jones (HM Principal Agricultural Inspector) minuted Mr J R Russell (Area Director, HSE) reporting that MAFF had recently contacted him regarding 'a potential serious health risk to persons required to handle cattle suffering from [BSE]'. ¹ He stated:

It was claimed, at my meeting, one haulier had already been badly mauled by such an animal - full details of this incident or its whereabouts are not known. Hauliers have expressed an opinion that because of the unpredictable behavioural pattern of BSE cattle they are being exposed to additional risk to their own health and safety.

8.28 Mr Jones recommended that further discussions should be held between 'ourselves' and MAFF Veterinary Service to 'promulgate a suitable Code of Practice for their handling'.

8.29 On 20 May 1988, having consulted MAFF on an earlier draft, HSE issued a circular entitled 'Bovine Spongiform Encephalopathy (BSE)' to Area Directors and Inspectors. The circular set out to alert Inspectors on the likely risks to handlers arising from changes in the behaviour of affected animals. ² On health and safety it stressed:

There is no evidence that cattle have become diseased by contact with animals of other species nor that any other species have been diseased by contact with live cattle or products from cattle.

There is some risk of physical injury when handling affected animals e.g. loading/unloading during transport to an abattoir and in this respect hauliers may be at particular risk. ³

Dr Pickles alerts HSE to the Southwood Working Party's concerns

8.30 In vol. 4: The Southwood Working Party, 1988-89 we discuss the first meeting of that Working Party, on 20 June 1988. One of the matters covered was the occupational health risks associated with BSE. ⁴ It was agreed that Dr Pickles should make enquiries into the health and safety aspects of BSE. ⁵ Accordingly, on 24 June 1988 she wrote to Dr Gompertz enclosing some background material prepared for the Working Party. ⁶ This included a list of questions, tabled by Sir Richard Southwood, and the answers that had been supplied. One of these asked:

15. What are the theoretical routes to man of parts/products of cattle, especially dairy cattle, before and after slaughter? ⁷

8.31 The answer (which had been provided by Dr Pickles herself) listed some of the potential occupational routes of transmission:

- surface contact with outer-hide: cowhands, vets, slaughtermen, tanners, leather workers

- surface contact with udders/milk: cowhands/dairymen

- surface contact with blood, flesh, brain: slaughtermen, butchers, cooks

- aerosol inhalation of blood: slaughtermen?

- inoculation of blood: vets during needlestick injuries

- surface contact with saliva, semen, placenta, blood and amniotic fluid during calving: cowhands, vets

- surface contact with misc. products: workers in various industries e.g. rendering, some pharmaceuticals

- laboratory workers exposed to fetal calf serum. ⁸

8.32 Dr Pickles suggested to Dr Gompertz:

The HSE interest could be two-fold, firstly in assessing whether occupational exposure to BSE has led to human disease, and this might be the only way we could ever know if the agent is pathogenic to humans, and secondly in reducing occupational risks.

. . .

There is also the issue about what protection if any is needed for those who have to continue to handle infected brain. The virologists examining brains take precautions (although I do not know if this is up to CJD standards). What precautions should be recommended for them, or others handling material from known affected cattle? ⁹

8.33 As a result, a meeting was called some weeks later (9 September 1988). We discuss this below.

CVL lead on guidance for veterinary laboratory workers

8.34 In the meantime, following enquiries about the potential risks involved in handling material from suspect BSE cases, MAFF had been giving consideration to the safety of its own staff. In July 1988, Mr Sweasey circulated guidelines for handling BSE material in the laboratory among the Superintending Veterinary Investigation Officers (SVIOs, MAFF). The guidelines, entitled 'Safe working procedures', were for use by MAFF staff at Veterinary Investigation Centres (VICs). They advised on necessary safety procedures when handling instruments, brain removal, storage, incineration, disinfection, protective clothing, fixation and accidental contamination when handling BSE material. ¹⁰

8.35 Also in July 1988, Dr Cawthorne (Head of the Veterinary Investigation Section, SVS, MAFF) sent an internal minute to all the SVIOs attaching guidance entitled 'Health and Safety at Work'. ¹¹ This gave advice in respect of both the 'physical' and 'infectious' risks whether in the field or in the laboratory. On physical risks it advised:

No action should be taken that will present a risk of injury. As behavioural changes will vary from case to case, as will handling facilities on farms, each case should be assessed on its merits. In determining action to be taken Ministry Staff should remember they have a responsibility towards farm staff as well as themselves, just as the farmer and his employees have responsibilities to avoid placing themselves or MAFF employees at risk.

. . .

Safety considerations do not end once the animal is dead as procedures for removal, transportation, incineration can all present physical risks if not conducted with care and forethought.

8.36 On infectious risks, the guidance stated that, while MAFF's view was that BSE did not present a risk to humans, their actions to date in disposing of the carcasses of suspect cattle were intended to reassure the public and ensure that confidence in beef/dairy products was maintained. ¹² It advised that thick rubber gloves be worn at all times when injecting suspects, waterproof clothing be worn if blood spillage was anticipated and no food or drink be consumed after handling. It also advised that all equipment used for stunning, injection or decapitation of suspects be stored and transported in robust containers prior to disposal or sterilisation; that bovine heads transported to VICs be double-wrapped in plastic bags; and that protective clothing be worn when handling nervous tissue, spleen, placenta and uterine fluid. On caesarean section it stated:

Many farmers appear keen to retain cows that are close to calving in the hope that they can at least salvage a calf from the cow. Deterioration is often rapid immediately prior to calving and requests may be received to allow the calf to [be] delivered by caesarean section at or before slaughter.

Despite the absence of a known risk to humans, given that the placenta of sheep infected with scrapie is known to be infectious, caesarean sections are contraindicated. ¹³

8.37 This advice was followed up in November that year by CVL guidelines entitled 'BSE and Scrapie - Guidelines on Some Safety Aspects - CVL'. ¹⁴ These were also for internal use. The guidelines advised that the BSE agent, which had not been listed by the ACDP in their Categorisation of Pathogens (1984), should be treated on a par with the Kuru and CJD agents, ie, Hazard Group 2 pathogens.

HSE's initial consideration of the Southwood Working Party's concerns

8.38 Following Dr Pickles's letter of 24 June 1988, Dr Gompertz and other officials from HSE met with her (9 September 1988). On 12 September 1988, in a minute to others in HSE, Dr Gompertz set out the views they had reached, describing these as 'tentative opinions of an ad hoc meeting'. He said that it had been agreed that there was no need to inform slaughterhouse men, butchers, or those in the animal feed industry about BSE as a hypothetical hazard to man. Hygiene precautions aimed at preventing other zoonoses were sufficient for the time being. He added that just as HIV infections had encouraged those at risk occupationally to improve their normal standards of work hygiene, BSE could be used as a stimulus to do the same with those handling animal carcasses, tissues and products. He emphasised that this should be done under the general umbrella of zoonoses and BSE should not be mentioned at this time. ¹⁵

8.39 Dr Gompertz also asked for views on whether an HSE/Local authority campaign, based on the prevention of zoonoses generally, should be initiated on these lines to improve hygiene standards in slaughterhouses, the meat rendering industry, animal feedstuff manufacturers and veterinary pathology laboratories and among producers of biological pharmaceuticals. ¹⁶

8.40 The suggestion did not meet with universal approval. Others at HSE responded that there were clear differences between the initiative based on BSE and the AIDS campaign. For instance, Dr Cottam (Microbiology Unit, HSE) said that AIDS presented a real risk to man of an incurable disease by a known route of exposure. In his opinion, BSE was not likely to be of significant risk to man. Also, there was generally insufficient information on the incidence of occupationally acquired zoonoses to initiate a campaign that would have the same impact as the one on AIDS. ¹⁷ He advised:

Different standards and approaches to safe working are required for such diverse activities as slaughterhouses/meat renderers and the producers of biological pharmaceuticals. Also different 'hygiene precautions' are required for different zoonoses.

8.41 In September 1988, HSE's Medical Division issued an internal memo informing others in the HSE about the latest developments. This stated:

There has recently been publicity about a new disease, BSE, which has been found in cattle in the UK. It is currently thought that this disease which only affects cattle, represents a cross species infection by the scrapie agent of sheep. There has also been speculation that a similar species transfer could occur leading to infection in humans.

Investigations carried out so far suggest that infection in cattle could have resulted from the practice of feeding concentrated animal protein obtained from offal (including brains) which contained the scrapie agent. On present evidence there is no indication that infection would be transmitted to humans in the same way.

Medical Division have opened discussion with representatives of the DoH and MAFF in respect of any possible occupational implications. It was agreed that there is no immediate need to inform slaughterhouse men, butchers, or those in the animal feed industry, about BSE as a hypothetical hazard to man . . . It was felt that just as HIV infection has encouraged all at risk occupationally to improve their normal standards of work hygiene, HSE could use BSE as a stimulus to do the same with those handling animal carcases, tissues and products. However, this should be done under the general umbrella of zoonoses and BSE, should not, at this time, be singled out . . . ¹⁸

8.42 The memo noted that CVL had produced guidelines for those in the MAFF veterinary service conducting post-mortem examinations on infected cattle, and that 'any others carrying out similar work should be encouraged to seek advice from CVL'. ¹⁹

8.43 Some weeks later (on 7 November 1988) Ms Maureen Holkham of HSE's Education NIG wrote to Mr Garstang of HSE's Medical Division about the reactions of the Health Services, Education and Food NIGs to Dr Gompertz's minute of 12 September 1988:

Within some higher education establishments, experimental and teaching work using a variety of animal species is extensive and the (unknowing) use of animals infected with zoonotic agents (including BSE) presents a foreseeable risk to health. However, the level of control exercised over incoming animal stock and the general environment probably helps to limit routes of infection. The NIG is aware of only one incident to zoonotic infection in this sector, namely an outbreak of Q-fever at Bristol University in 1981 (15 people infected in animal house and veterinary school laboratories following post-mortem examination of sheep).

Because of the low incidence of infection, the Education NIG could not advocate that a high priority be given to a hygiene standards campaign. Obviously, other NIGs may have different experience, and if an HSE campaign is sanctioned, we would like to keep an overview. ²⁰

8.44 Mr Garstang passed this on to Dr Gompertz on 24 November 1988, advising that although the Health Services, Education and Food NIGs acknowledged a foreseeable risk to health from BSE within their sectors, there was minimal evidence of zoonotic infection within the Factory Inspectorates area of work. There was little evidence to support the need for a campaign to improve hygiene standards. ²¹

8.45 Although it does not appear to have been referred to the Education NIG, a school safety issue concerning the dissection of bovine eyeballs had arisen separately. This is reviewed in the Chapter 9: Bovine Eyeball Dissection.

Further involvement of Dr Pickles and the Southwood Working Party

8.46 On 15 November 1988, Dr Pickles wrote to Dr Gompertz updating him on the Southwood Working Party's progress. ²² She said that the Report was likely to state that HSE had been alerted to the possibility of occupational exposure and had been asked to take any steps thought appropriate. The Southwood Working Party also wished to draw particular attention to those who handled placenta, which was considered a particularly potent source of infection.

8.47 In the meantime, HSE promoted general improvement in work hygiene standards in response to occupational queries about BSE. ²³

Sir Richard Southwood raises health and safety aspects of calving and lambing

8.48 On 24 November 1988, at a meeting with Ministers and the CMO, Sir Richard Southwood raised his concern about health and safety aspects of handling animals. ²⁴ Mrs Shirley Stagg (Principal Private Secretary to the Minister) sent Mr Cruickshank (Under Secretary, MAFF) a minute of the meeting which noted:

Sir Richard was concerned about health and safety aspects of handling animals when slaughter took place on the farm or when handling calving (the placenta of animals was considerably infected). If people were handling animals and had lesions in their skin then they could become infected with material from the animal. Current HSE regulations were not adequate to deal with this. Mr Meldrum was concerned that to introduce new precautions would escalate the issue unnecessarily when we were saying there was no hazard to man from BSE or indeed from scrapie. Sir Donald [Acheson] pointed out that there was doubtless a code of practice for people handling infected animals at CVL. Mr Thompson thought that it should be possible to produce a sensible code of practice governing the slaughter of animals on farm. He was however concerned about precautions for calving and lambing. Sir Richard thought that the point could readily be dealt with by warning people about handling animals if they had lesions in their skin. This could be a very general warning and need not be alarmist. It could possibly be incorporated in HSE rules. ²⁵

8.49 At the Southwood Working Party's next meeting, on 16 December 1988, the members agreed that HSE's current line was appropriate. This was not to provide specific advice about BSE but to advise those generally coming into contact with livestock on the risks from 'zoonoses'. ²⁶