On Monday I reported (see MOA: Large Poultry Die Off In Heilongjiang - H7N9 Confirmed (HPAI Suspected) on what appeared - based on reported avian mortality - to be the farthest north outbreak of HPAI H7N9 to date, on a breeder farm only a few miles from the Russian border.
Today the OIE has confirmed HPAI H7N9, in the following announcement:
Since it emerged in 2013, we've seen a good deal of speculation as to when H7N9 would finally follow its HPAI H5 cousins and break out of Mainland China and begin to spread internationally (see FAO Warns On H7N9 In China).
For most of that time, the assumption was that Southeast Asia - most likely Vietnam, which shares a porous border with China - would be the first to encounter the virus (see Vietnam Wary Of H7N9).But with the emergence of HPAI H7N9 in January, and its steady northward push over the past 5 months, Russia now finds the virus confirmed within 100 miles of its territory, and that increases its chances of spreading even further via the Asian migratory bird flyways.
While these flyways are predominately north-south corridors, their overlapping allows for a degree of lateral (east-west) movement of avian viruses as well – often via shared nesting areas and ponds.
Which explains how HPAI H5N1, HPAI H5N8, and H5N6 have all managed to expand their geographic range both east (to Korea, Japan, and North America) and west (to Europe, the Middle East, and Africa) in recent years.It remains to be seen whether H7N9 has adapted well enough to migratory birds to follow suit, but this abrupt geographic expansion warrants close attention.