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Risks in perspective

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THE main theme of this year’s BVA Congress – ‘Biosecurity: the big issue’ – was pertinent at the time, but seems to have become all the more so with each passing day. The congress, which emphasised the importance of biosecurity at international, national and local levels, was held from September 30 to October 1, just a few days before an outbreak of highly pathogenic avian influenza was reported on a turkey farm in the Balikesir region of Turkey. Confirmation of this outbreak, and of a further outbreak in eastern Romania (VR, October 22, 2005, vol 157, p 494), meant that, having been circulating in south-east Asia for some time, the virus responsible had found its way to the edge of the EU. The interest generated by this development has been considerable. It would have been better if it had not spread – but it would be hard to invent a better illustration of the need to maintain biosecurity or a more spectacular demonstration of the level of concern an animal disease outbreak can cause.

In this case, the concern has been heightened by fears that the virus could mutate into a form that is transmissible between humans, leading to a global influenza pandemic. For the time being, this has not happened and avian influenza remains a disease primarily affecting birds, albeit one that can infect man. Every effort must be made to stamp out the disease, and to keep it out of regions that are currently unaffected. It is also important that veterinary agencies work closely with those responsible for human health. However, amid all the media coverage in Europe over the past few weeks, it seems almost to have been forgotten that, if the virus were to mutate into a form transmissible between humans, this is most likely to happen in regions where the viral ‘load’ is greatest and where humans and poultry are in close and frequent contact. Biosecurity clearly needs to be maintained at borders, but, in this respect, there is an even stronger case for investing in animal disease control internationally and tackling emerging disease problems at source. One can never be sure if and when such a mutation might occur, but, if it does, the risk to humans is likely to be greater from travelling people than is currently the case from, say, migrating birds.

The need to remain vigilant, and to be alert to all possible avenues by which virus might be introduced, was illustrated by the reported isolation of a highly pathogenic avian influenza virus from imported wild birds in a quarantine facility in Essex last weekend. This may be an isolated incident, but it has illustrated the disease risks associated with trade in wild animals, as did the 2003 outbreak of monkeypox virus in the USA. In the current circumstances, the EU’s decision to impose a ban on the importation of wild birds into Europe seems justified.

Vigilance is necessary at every level and, as emphasised in the BVA’s briefing document on avian influenza, which is available at, crucially applies to ‘backyard’ as well as to commercial flocks. Biosecurity is equally vital and, to this end, DEFRA has recently produced a guidance leaflet, ‘Protect your birds from the risk of avian influenza (bird flu)’, for all flock owners. This is available from the avian influenza section of DEFRA’s website ( The leaflet has been mailed to veterinary surgeons and a copy is also enclosed with UK copies of this issue of The Veterinary Record. Further copies of the leaflet (product code PB11393) are available from DEFRA Publications, Admail 6000, London SW11 2XX, telephone 08459 556000, fax 020 8957 5012, e-mail: defra{at} DEFRA has also produced a leaflet aimed at larger commercial bird farms (product code PB11380) and an A3 poster outlining biosecurity steps and signs of the disease (product code PB11399), which are available from the same address. Advice on ‘assessing risks of avian influenza where poultry are kept’ has been posted on DEFRA’s website.

The BVA’s Avian Influenza Advisory Group (VR, September 17, 2005, vol 157, p 329) continues to help formulate advice on the issue and has had an input into DEFRA’s biosecurity leaflet, along with other stakeholders. At present, the group is in the process of formulating advice for members on dealing with inquiries from members of the public; working with the relevant government agencies, it is also seeking to develop advice on protective measures that might be taken by veterinary surgeons if they are presented with a suspected case. This will be posted on the BVA’s website as soon as it is finalised. The group is also seeking to clarify with DEFRA advice on drawing up contingency plans with poultry keepers.

With the help of its advisory group, the BVA has also submitted both written and oral evidence to the House of Lords Science and Technology Select Committee’s inquiry into contingency planning for the possibility of a human influenza pandemic (VR, September 17, 2005, vol 157, p 329), which is expected to report by the beginning of next year. While pointing out that the risk of a human pandemic originating in the UK was currently very low, it argued that those working closely with poultry should be vaccinated annually against human influenza to reduce the potential for viral mixing. It also argued that the Government should take steps to ensure that those working with poultry have access to antiviral therapies in the event of an outbreak of avian influenza. It is important to plan for the possibility of a human pandemic, but it is also important to keep the risks in perspective. While mutation of the virus is always a possibility, the immediate challenge is to prevent and contain infection in birds, and current efforts must be devoted to that end.

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