Credit OIE Report
Over the past eight months we’ve seen a resurgence of HPAI H5 activity around the world, with H5N8 spreading from Asia to North America and Europe, the emergence of local reassortments (H5N2, H5N3 & H5N1 N/A) with H5N8, and a major uptick in H5N1 activity in Africa and Eastern Europe.
Not only has Egypt reported the largest, and longest, outbreak of H5N1 in humans - countries that have not reported the virus in years (i.e. Nigeria, Burkina Faso, Turkey, Russia, Bulgaria, Romania, Hungary, etc.) have reported outbreaks either in poultry, or wild birds.
While it could be argued that the HPAI H5 viruses like H5N8 and H5N2 are spreading quickly because they are somehow better adapted for carriage in wild or migratory birds, exactly why H5N1 has taken off after several years of relative quiescence is harder to deduce.
Today the OIE has posted a notification that Iran has detected H5N1 for the first time since 2012, in the village of Nogardan in Mazandaran province, where it killed a small number of chickens. While not in itself a particularly earthshaking story, it is another indication that H5N1 continues to spread in the region.
Source of the outbreak(s) or origin of infection
- Unknown or inconclusive
1 - The event was reported according to Iran passive surveillance in place. 2 - A post-outbreak investigation is ongoing to trace the source of infection, and to detect a probable spread and circulation of the virus. 3 - Active surveillance is ongoing.
- Control of wildlife reservoirs
- Stamping out
- Movement control inside the country
- Disinfection / Disinfestation
- Vaccination prohibited
- No treatment of affected animals
Why HPAI H5 viruses have suddenly taken flight over the winter of 2014-15 remains a mystery, but we’ve not seen this level of bird flu activity since the great H5N1 diaspora of 2005-2006 (see H5N8: A Case Of Deja Flu?).
Summer is historically the `off season’ for avian flu viruses, so one can’t help but wonder what kind of fall lies ahead.