Qinghai H5N1 in England is Likely
Recombinomics Commentary
February 3, 2007
The first deaths happened on Tuesday 30 January when 71 chicks died, said Defra.
A further 186 died the following day and 860 died on 1 February. Some 1,500 died on Thursday, making a total of 2,617.
The above description of turkey deaths on a farm near Lowestoft in Suffolk in England strongly suggests the H5 positive turkeys were infected with the Qinghai strain of H5N1. Last season H5N1 was reported throughout Europe, the Middle East, and Africa. All highly pathogenic H5N1 was the Qinghai strain, with the characteristic HA cleavage site of GERRRKKR or a close derivative sequence.
Qinghai H5N1 is transported and transmitted by wild birds. Although Great Britain has a surveillance program for wild birds, the detection rate has been remarkably low. In the 2006/2007 season, 2344 live birds were tested. Seven teal and four mallards were positive for low path avian influenza. There were four low path viruses identified in 661 birds shot by hunters. Among 1049 dead birds, avian influenza was found in two. Thus, the detection rate was below 0.5%, raising serious questions about the sensitivity of the testing. The results this season failed to find high avian influenza. Last season one H5N1 infected bird was identified and the surveillance failed to detect H7N3, which infected the same region last spring. Last seaon H7N3 was confirmed in one poultry worker.
These detection failures are cause for concern. Last year many countries in Europe detected H5N1. The total number of positives exceeded 700 birds, which were largely in wild birds. However, Most of these countries also failed to detect the H5N1 until January / February, 2006, although H5N1 migrated into the region in the fall of 2005.
This year, Hungary and Krosnodar have reported confirmed H5N1. Several countries in Africa, including Egypt have confirmed H5N1. The failure of other European countries to detect or report H5N1 this season is cause for concern.
H5N1 with Tamiflu resistance marker NA N294S in the Gharbiya cluster. The isolates also had HA M230I, encoded by sequences found in H5N1 in Asia. However, other Qinghai H5N1 infected birds in Egypt have M230I encoded by sequences found in H7N3 isolated from the 2006 outbreak in England suggesting dual infections and recombination in birds infected with H7N3 and H5N1, which highlight further the poor surveillance in Europe.
H5N1 continues to rapidly evolve via recombination. Monitoring this recombination has been hampered by the sequence hoarding by Weybridge in England. The vast majority of Qinghai H5N1 from the 2005/2006 outbreak in Europe and the Middle East remains sequestered in the WHO private database at Los Alamos.
The recent WHO summary of avian influenza released in December, 2006 indicates H5N1 is evolving by a mechanism of random mutations generated by an error pronce polymerase lacking a proof reading function: "As influenza A lacks a "proof-reading" mechanism for DNA repair and fails to correct small errors that occur in viral replication, constant genetic mutation is a characteristic feature of all influenza A viruses, including H5N1."
This interpretation is inconsistent with the public H5N1 sequence data. These inconsistencies would be further enhanced by the releases of the hoarded data. The time to release this data is long overdue.
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