Chief Veterinary Officer, Exotic Diseases & Trade, Dept of Agriculture, Fisheries & Forestry
The management of new and emerging diseases poses many difficulties for animal health authorities because decisions need to be taken when there is often a distinct lack of knowledge. BSE poses additional problems including the fact that it can take many years to manifest itself in a clinical manner, can cause death in humans and puts a cloud on the safety of a wide range of products from cattle. Australian approaches to BSE prevention and management from 1988 to the present and future direction are summary of how Australia has adopted a multi-disciplinary approach and, arguably has introduced measures more stringent than those in other parts of the world. The National Health Medical Research Council (NHMRC) has indicated that the risk of “mad cow disease” has been reduced because of an early response by Australia. However additional measures need to be introduced in the light of new knowledge.
The management of new and emerging diseases is difficult due to the many unknowns in these situations, including public health consequences. Nevertheless animal health authorities must make decisions on the basis of professional experience and qualitative judgement of risk. Australia has performed extremely well in dealing with a range of incidents such as Hendra virus, lyssavirus, Menangle virus, Japanese encephalitis and a range of new marine organisms. Australia is well recognised for its competency in this area.
BSE poses additional problems. These include a lack of knowledge of the science of prion particles, difficulty in quantifying public health risk, trade impacts, lack of consumer confidence in scientific advice, publicity and the need to adjust management systems to accommodate to the changing understanding of the disease. Further the fact that BSE takes many years to manifest itself in a clinical manner and tests to detect pre-clinical cases are not available means that authorities have to anticipate and deal with possible events many years down the track.
Australia’s responses to BSE can be considered over three time periods – 1988-1996, 1996-2000, 2000- present time.
When Australia became more aware of the BSE situation, prohibitions were placed on the importation of cattle and genetic material in 1988. This action supplemented very conservative quarantine policies that had been in place for a number of years, for example only allowing the importation of animal feedstuffs from New Zealand and introducing measures to prevent scrapie entering the country. Live animals were progressively refused entry into Australia from countries where BSE occurred, for example Switzerland, France and Ireland.
In 1992 OIE introduced refinements into its Code Chapter on BSE including surveillance and monitoring. Australia met and often exceeded OIE standards, awareness of the nature of BSE and other spongiform encephalopathies increased, pathologists were trained in BSE diagnosis and BSE was made a notifiable disease. This awareness and interest in part contributed to the diagnosis of a spongiform encephalopathy in a cheetah (the first such recorded in the world) imported from the UK to a zoo in Western Australia.
In 1996 the UK Government announced the possible association of BSE with a variant CJD in humans. This resulted in voluntary restrictions on the UK’s part of exports of a range of its cattle and cattle products. The Australian Chief Veterinary Officer called together an urgent meeting of health authorities to determine collectively the range of additional measures that would be necessary to protect human health, animal health and trade in the light of developments in Europe and the scientific knowledge available at the time.
Measures included additional import restriction, the introduction of ruminant feedstuffs bans and enhanced monitoring and surveillance. Most importantly a scientific committee Chaired by Professor Colin Masters of the Australian CJD Registry was established to advise the BSE committee jointly Chaired by the Australian Chief Veterinary Officer and Australian Chief Medical Officer. Commonwealth, State and Territory agricultural Ministers agreed to the range of measures instituted. As a result of these activities the European Union accorded Australia with a Geographical BSE Risk rating of 1 – which meant in its view it was highly unlikely BSE existed in its clinical or pre-clinical form.
An independent commission into the UK BSE incident published its report in 2000 (the Phillips Inquiry). Although Australia had introduced a number of arrangements which were mentioned in the Phillips Report, there were still a number of lessons others could learn from the UK experience. In the year 2000 the European Union applied additional measures particularly in regards to the banning of a range of proteins in animal feedstuffs.
A National Health and Medical Research Council (NHMRC) committee was established to review the science and make recommendations to Government on human and animal health risks. Matters the NHMRC has and is examining include vaccines, blood, feedstuffs, therapeutic agents, surgical materials, fertilisers, waste disposal and food products.
Agricultural Ministers established a National Management Group to examine procedures in primary industries, identify gaps and make recommendations to Ministers on any additional measures that should be applied. In addition Ministers extended the range of animal feeds included in the ruminant feedban, agreed to enhance compliance and audit activities and supported the development of rapid testing methodologies. BSE will be on the Council of Australian Government Ministers agenda in June.
There are a great number of activities taking place on the international front. These include research work, development of international standards for purposes of trade and introduction of legislation for example in the European Union. The Office International des Epizooties, World Health Organisation and Food and Agricultural Organisation will hold a joint expert international consultation in June 2001 to examine risk and risk management procedures. It is likely that subsequent to this meeting a number of countries will carry out their own BSE risk analysis.
Australia has had in place systems to minimise the likelihood of BSE entering or becoming established in Australia for many years. This has been done on the basis of risk and it has included a range of protective measures including quarantine, animal feed restrictions, surveillance/monitoring, scientific review, audit of management systems, emergency management and training of pathologists. A multi-disciplinary approach has been taken, there has been full support by Ministers, and legislation introduced where appropriate.
Australia’s approach to BSE has been as good if not better than most like countries. The NHMRC has said that “risk of ‘mad cow’ disease has been reduced by an early response in Australia”.
However, given a lack of a full understanding of BSE there are no grounds for complacency and therefore Australia must continue to monitor the situation and introduce appropriate measures in the light of new information to maintain our freedom. In particular Agriculture Fisheries Forestry Australia (AFFA) will continue to provide information to NHMRC for its assessment and advice.