Just over 10 years ago, between May & June of 2005, the world watched as the H5N1 virus – which had been pretty much restricted to small outbreaks in Southeast Asia - sparked a massive die off of birds at Qinghai Lake in China (see H5N1 Influenza Continues To Circulate and Change 2006 by Webster et. al.).
Suddenly, and unexpectedly, waterfowl (brown headed gulls, cormorants, ducks, geese, etc.) had died by the thousands at Qinghai lake from the H5N1 virus.
As flu viruses mutate, new strains are continually produced that are either `biologically competitive’ and go on to spread, or are not, and quickly fade away. When one of these competitive strains diverges enough genetically from its ancestors, it is designated as being a new `clade’ of the virus. Essentially a new branch on the virus’s phylogenetic tree.
What emerged at Qinghai Lake was clade 2.2 (aka QH05) of the H5N1 virus. And over the next 18 months, this new clade managed to spread far and wide on the wings of migratory birds across Asia, and into Europe and Africa.
In 2009 researchers found evidence of another clade (2.3.2) (see 2011 EID Journal New Avian Influenza Virus (H5N1) in Wild Birds, Qinghai, China), which was detected dead birds in the same region. In short order the 2.3.2 clade began to show up in migratory birds, and poultry, from Japan to India, supplanting the old 2.2 clade in many regions.
Today we are getting some very sparse details of a new, and relatively large, die off of birds at Qinghai lake, in the form of a very brief announcement from China’s Ministry Of Agriculture.
Date: 2015-07-17 14:00
Since early July, the stone is Hai Hainan prefecture, Qinghai County Republican township of death to the public village Pallas's Gull, as of July 15, 2361 death. July 17, the National Avian Influenza Reference Laboratory detection of highly pathogenic avian influenza virus subtype H5N1 deaths expected from the disease sample Pallas's Gull submission of Qinghai Province.
At present, Qinghai veterinary departments have jointly forestry sector in accordance with the emergency plan and control technical specifications, really good job in emergency work. The investigation found no local poultry anomalies.
A Pallas's gull or great black-headed gull, is a migratory seabird that winters in the eastern Mediterranean, The Middle East, and India, and spends its summers in Russia, China, and Mongolia.
There is no word on the clade of H5N1 responsible for this die off, nor any indication that anything `new’ has occurred here. We are, however, seeing heightened HPAI H5 activity around the globe, and so events such as these are worth our attention.