Commentary
Another Hokkaido H5N1 Confimation Raises Migration Concerns
Recombinomics Commentary 17:48
May 5, 2008
The deadly H5N1 strain of avian influenza has been detected in a dead swan found April 24 on the Notsuke Peninsula in eastern Hokkaido, the Environment Ministry said Monday.
Another dead swan found Monday beside Lake Saroma in eastern Hokkaido was also found to be infected with bird flu virus through a preliminary examination, the Hokkaido prefectural government said.
The above comments describe a second H5N1 positive swan in Hokkaido (see satellite map). The latest outbreaks in Hokkaido and Akita are markedly north of prior outbreaks. A detailed report on the earlier outbreaks includes phylogenetic trees that include last years isolates (listed below), and includes migratory routes between Japan and Asia based on satellite tracking. These data confirm that the H5N1 in Japan in early 2007 was closely related to the H5N1 in South Korea in late 2006, which was the Uvs Lake strain of clade 2.2. The migration data link swans in northern Japan to areas due north in northeastern Siberia. Movement of H5N1 to northeastern Siberia would set the stage for transfer to species in Alaska, followed by the migration of H5N1 south into Canada and the United States.
The confirmation of H5N1 in northern Japan as well as southeastern Russia suggest that H5N1 is expanding into new areas to set the stage for a migration into North America. However, the current surveillance approaches, which are largely directed toward cloacal swabs and fecal collections which are not likely to detect the H5N1, which is highest in tracheal swabs or organs from hunter killed birds.
A/Ck/Miyazaki/S749/07
A/Ck/Miyazaki/H358/07
A/Ck/Miyazaki/K11/07
A/Mountain hawk-eagle/Kumamito/1/07
A/Ck/Okatama/T6/07
Media Links
Recombinomics Presentations
Recombinomics Publications
Recombinomics Paper at Nature Precedings