H5N1 In Delaware
Recombinomics Commentary
November 18, 2006
The updated USDA table of detection of H5N1 in the United States identifies positive green winged teal in Sussex County, DE. Further testing is underway. However, the updated table included two more failures to isolate virus from H5N1 positive samples in New York, and raises serious questions about the methodology and resource allocation of the surveilance program.
The vast majority of the samples are from hunter killed birds, yet the only positive sample from hunter killed birds is from mute swans in MI. Detection of the Qinghai H5N1 strain in Europe was most frequent in mute swans. Similarly, a second positive sample was from environmental samples in MD, which is also the source of most H5N1 positives in the recent PNAS paper on the spread of the Fujian strain of H5N1 in China.
Live birds have yielded H5 virus (H5N1 and H5N3) in PA and MT, while all hunter killed ducks (green winged teal, mallard, northern pintail, northern shoveler) are either still being tested, or have failed H5 virus (H6N2 was isolated from an IL sample and the remaining samples were negative for virus).
The widespread detection of H5N1 in hunter killed ducks, raises questions about failures to detect H5N1 in other sources. The failure to isolate H5N1 from five locations, and the fact that the seven locations still being tested are also from hunter killed birds, raises questions about detection failures in live birds and environmental samples.
These failures in H5N1 positive birds, raise questions about repeated failures to detect H5 in dead birds, or even report H5 positive dead birds in Lakeport, CA.
The failure to isolate H5N1 from any source since August, in spite of widespread detection throughout the United States, raises serious questions about the surveillance program in the United States and Canada, which also has not announced H5N1 isoaltions for this year, and has only released one partial sequence from H5 isolated throughout Canada in 2005.
Moreover, the size of the PCR insert in the H5 detected in a dead farm goose on Prince Edward Island has been withheld, raising additional concerns about Qinghai H5N1 in North America, since the positive goose had H5N1 symptoms, and death was rapid for all four farm geese with H5N1 symptoms.
The H5 sequence contain valuable information about the acquistion of H5N1, swine, and human sequences. Sequence data from H5 in the United States and Canada should be released immediately.
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