Qinghai H5N1 Confirmed in Japan
Recombinomics Commentary
January 23, 2007
The test results showed that the strain found on the Kiyotake farm was at least a 99-percent match in terms of DNA sequencing with the H5N1 strain confirmed in China in May 2005
Several thousand migratory birds have been killed by avian flu at Qinghai Lake, China's largest lake, in the western part of the country.
The above comments confirm the Qinghai strain of H5N1 in the initial outbreak in Japan this year. This confirmation was not a surprise because Qinghai had been confirmed in South Korea at the end of 2006, and the outbreaks were following the same pattern that was reported in 2003/2004 when H5N1 was reported in South Korea, followed by similar outbreaks in Japan. Moreover, the sequences in Korea and Japan in 2003/2004 were precursors to the Qinghai strain, which was first reported at Qinghai Lake in May, 2005, folowed by migration to Siberia and Mongolia. Whooper swans migrate from Mongolia to South Korea.
Although the Fujian strain was widespread in live markets in southern China in 2005/2006, the surveillance found only one reported Qinghai sequence (in a Guinea fowl in Shantou). However, the failure to find significant Qinghai infections in southern China, did not signal that the Qinghai strain was being replaced by the Fujian strain.
The Qinghai strain spread westward after migrating to southern Siberia and Mongolia in the summer of 2005. All subsequent reports of H5N1 in Europe, the Middle East, and Africa were the Qinghai strain. Therefore detection of the Qinghai strain this season in South Korea and Japan was not surprising.
Similarly, the H5N1 outbreaks in Egypt have also been the Qinghai strain. The sequences this season have the genetic background defined by last years isolates, but have added new polymorphisms, some of which have been identified in Shantou geese.
Release of the Qinghai sequences in South Korea and Japan as well as the sequences from last season in Europe and the Middle East would be useful.
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