Massive H5N1 Bird Flu Die-off in Tuva, Siberia
Recombinomics Commentary
June 27, 2006
The Siberian office of the Russian emergencies ministry Tuesday said the outbreak of the H5N1 strain of bird flu in the constituent Tuva Republic was intensifying.
The emergencies ministry first reported June 23 that 169 dead wild birds had been collected from the Ubsu-Nur Lake in the Ovyursky district of the Tuva Republic, and the presence of H5N1 in their blood samples had been confirmed by the Kemerovo veterinary laboratory.
Tuesday's statement said wild bird deaths were continuing, with 371 new deaths reported by Sunday afternoon. A total 1,622 birds have died since the first were found on the lake June 15.
The above report describes a massive number of H5N1 deaths in Tuva, which is in southern Russia, just to the north of Mongolia. Other reports indicate the number of dead birds is up to 3,339. The size of this outbreak is rivaling the deaths at Qinghai Lake in May, 2005 which topped 5000 dead birds primarily bar head geese. This year there is another outbreak somewhat south of Qinghai Lake near the southern border of Qinghai Province and northern border of Tibet. Over 1000 birds have died including ba headed geese and a number of other species. The recent wild bird meeting in Italy included phylogenetic trees of H5N1 from bar headed geese in China this year, indicating the isolates were most closely related to a crested Grebe from Novosibirsk or whooper swans from Mongolia.
This latest outbreak in Siberia suggests more H5N1 may be spreading worldwide this year. In 2005, there were no H5N1 reported until mid-July. The H5N1 this season may be more complex genetically because the H5N1 from Qinghai Lake on Novosibirsk evolved considerably in Europe as seen by the phylogenetic tree of over 70 isolates.
Thus, 2006 will likely see new sequences and new problems.
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Phylogenetic Trees