Hungarian Poultry "Most Plausible" Route of Bird Flu Transmission – Report 

16/02/07 In response to the outbreak of avian influenza in Suffolk in the UK two reports have been published.

A Defra interim epidemiological report identifies two possible hypotheses for the introduction of H5N1 into the poultry premises at Suffolk:

• The report concludes that there is 'little evidence' to support the first hypothesis of transmission from a wild bird source. This draws on advice from expert ornithologists and the fact that H5N1 has not been found in the wild bird population in Europe since August 2006. In addition to this, extensive surveillance from the Infected Premises and the surrounding area has not isolated any trace of H5N1 in wild birds.

• The second hypothesis examined in the report is the spread of the virus associated with the importation of poultry products from Hungary. This is supported by the final virology results from the Veterinary Laboratories Agency (VLA) confirming that the virus strain found in poultry in Suffolk is 'essentially identical' to that which caused the outbreaks in Hungary.
 
The interim report therefore concludes that 'currently the most plausible' route of transmission is associated with the importation of poultry products via Hungary.

Fred Landeg, Deputy Chief Vet, said: 'We are still yet to reach a final conclusion and our investigation will continue to be all-embracing in respect of possible means of introduction of the virus. However, these reports set out the current state of expert thinking and explain the rationale behind the most plausible explanation for how transfer of the virus could have occurred. It should nonetheless be recognised that we may never be able to conclusively pinpoint the original source of the virus.'

The joint final report by the Food Standards Agency (FSA), Defra, HPA and MHS examined transmission via imported Hungarian turkey meat. The FSA-led part of the investigation was launched to check whether meat from a restricted zone in Hungary had been brought to the Bernard Matthews plant at Holton, Suffolk.

This followed the hypothesis that there may be a link between the Hungarian outbreaks and the avian influenza outbreak in Suffolk. If it had been discovered that meat exported from Hungary to the UK had come from inside an avian influenza restricted zone, this would have been illegal under EU law.

Its main findings are:
• there is no evidence that any meat entered the UK food chain from the restricted zones in Hungary

• from evidence gathered by the FSA investigation team it appears that all food importing and processing activities being undertaken at the Bernard Matthews factory at Holton are in line with EC law

• the outbreak of H5N1 avian influenza does not alter the FSA's advice that properly cooked poultry meat remains safe to eat

Andrew Wadge, Food Standards Agency Chief Scientist, said: 'This report shows that according to the best available evidence no turkey meat from areas previously infected with avian influenza in Hungary was received at the Bernard Matthews plant in Holton.

'It is important to remember that this investigation has always been about the illegality or otherwise of meat imported into the UK, and not about food safety. We reiterate our advice that properly cooked poultry meat does not pose a food safety risk.

The HPA’s investigation focused on establishing if there was any health threat to the workers in the processing plant, or the wider poultry farm. Their assessment concluded that the risk to the workers health was very low and, as a result, they didn’t require any antiviral treatment. The assessment also took into account a number of pieces of current information, including:

• there had been no reported human flu cases associated with the outbreak in Hungary

• any level of virus in meat would decrease during the transportation

• the processes being carried out at the plant were not deemed to be high risk

The risk to food-processing workers and other personnel working in around the Bernard Mathews food plant has been assessed by the HPA as being very low.