H5 Confirmed in England
Recombinomics Commentary
February 2, 2007
Vets from the Department of Environment, Food and Rural Affairs (Defra) said the birds had tested positive for H5 avian flu.
The above comments strongly suggest Qinghai H5N1 has been detected on a commercial turkey farm in England. In one shed the mortality was 80-90%, strongly suggesting the H5 was HPAI and would be the Qinghai version of H5N1.
All HPAI H5N1 west of China has been the Qinghai version (clade 2.2). This outbreak in England is the second in as many years. Last year’s low path H7N3 was also not detected prior to infections on farms in the same region. The detection failure highlights the poor surveillance / reporting worldwide, including England.
Recent sequences from birds in Egypt raised questions about the distribution of H5N1 in Europe. There was a convergence of M230I in the Nile Delta. M230I had been detected in human cases, including the sequences from the Gharbiya cluster. Birds in the region also had M230I, but most encoded the change with the sequence found in H7N3 in the outbreak in England last year. The sharing of the same coding sequence between H7N3 and H5N1 suggested dual infections and recombination were involved.
Although H5N1 has been reported in Hungary and Krasnodar, other countries in Europe have failed to detect or report H5N1, although the outbreaks in Egypt and Nigeria strongly suggested that H5N1 migrated through the region this season, just as it had last season.
These migrations lead to further recombination and evolution, as the H5N1 in the long range birds recombines with the regional H5N1 and local birds infected with other serotypes to produce more diversity.
The presence of H5 in the heart of England’s poultry growing region and on a farm owned by the largest turkey producer in Europe, is cause for concern.
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