#15,582
The global uptick in HPAI (Highly Pathogenic Avian Influenza) - which began in August in Western Siberia after 3 years of relative quiescence, continues to expand both in Asia (mostly Japan & South Korea), the UK, and much of Europe.
In Europe, the UK, and Russia the primary culprit is the recent arrival of a new variant of HPAI H5N8 that has been described as being `genetically distinct' from recently circulating strains in the region (see Pre-Print: Novel Incursion of a HPAI H5N8 Virus in the Netherlands, October 2020).
We've also seen some other scattered HPAI subtypes (H5N5, H5N1) caused by reassortment of this H5N8 variant with local LPAI viruses. As we've discussed often, Clade 2.3.4.4 H5 viruses have demonstrated a highly promiscuous nature, and occasionally spin off reassortments.
DEFRA's last update on avian flu activity in Europe - published 6 days ago - listed only 5 European nations reporting outbreaks; (UK, Ireland, Denmark, Netherlands & Germany).
Today's update lists 10; (UK, Ireland, Denmark, Netherlands, Germany, France, Belgium, Croatia, Sweden, and Italy). But overnight there are media reports from several other countries, including Slovenia and Poland, of outbreaks and/or detections of avian flu.
I've posted some selected excerpts from today's DEFRA report below, but you'll want to follow the link to read it in its entirety.
Updated Outbreak Assessment #6Highly pathogenic avian influenza (HPAI) in the UK,and Europe
24 November 2020
Ref: VITT/1200 HPAI in the UK and Europe Disease Report
Since our last report on 17 November, in the United Kingdom there has been one new outbreak of HPAI H5N8 in poultry, three new reports of HPAI H5N8 in wild birds, and one new outbreak of HPAI H5N8 in captive birds. Elsewhere in Europe, H5N8 has been reported: in poultry in Croatia, Denmark, France (Corsica), Germany and Sweden; in wild birds in Belgium, Denmark, Germany, Ireland and the Netherlands; and in captive birds in the Netherlands. HPAI H5 has been reported in wild birds in Denmark and Italy; and HPAI H5N5 in captive birds in Germany, and wild birds in the Netherlands.
Situation Assessment
In the United Kingdom, since our last report on 17 November, there have been new reports of HPAI H5N8 in poultry, wild birds and captive birds.
Following confirmation of HPAI H5N8 in captive birds, on 20 November 2020 at a wetland centre near Stroud in Gloucestershire, a 3km Captive Bird (Monitoring) Controlled Zone has been put in place around the site.
There has been one new outbreak of HPAI H5N8 in poultry. HPAI H5N8 as confirmed on 23 November in poultry and captive birds at a premises near Melton Mowbray, Leicestershire: at a theme park containing multiple species, including domestic and exotic birds.
A 3km and 10km Temporary Control Zone has been put in place around the premises. In England, in Lincolnshire (near Boston), HPAI H5N8 was reported in a Eurasian Wigeon, three Brent geese, a Shelduck, a Canada goose and two Greylag geese.
In a nature park in Lancashire HPAI H5N8 was confirmed in an unspecified wild bird. In Northern Ireland, near Lough Beg (on the border between County Londonderry and Country Antrim), a Mute swan tested positive for HPAI H5N8. Lough Beg is a stopping point for migratory birds.
HPAI H5N8 in Western Europe
In Belgium, on 20 November, there were three reports of HPAI H5N8 along the north coast in West Flanders; in a European herring gull, a Eurasian Curlew, and a number of captive birds described as mute swans.
On 21 November, Croatia reported one outbreak of HPAI H5N8 in domestic poultry. Increased mortality had been observed on a large commercial premises with approximately 70,000 turkeys. The farm is in Delovi in the county of Koprivnica- Križevci.
Implementation of disease control measures according to the Directive 2005/94/EC have been put in place, and epidemiological investigations are ongoing.
Since our last report on 17 November, Denmark has reported one outbreak of HPAI H5N8 in poultry on a commercial poultry farm, containing approximately 25,000 birds. There have also been 20 reports of HPAI H5N8 in wild birds, and two reports of HPAI H5 in wild birds. While most reports continue to be from Jutland, there were a small number from Sjaelland (Zealand). Eleven of these reports related to dead barnacle geese. Other species included a brent goose, common buzzards, peregrine falcons, a curlew and a herring gull.
France has reported one outbreak of HPAI H5N8 (as reported to the OIE) in poultry. This was in the pet department of a garden centre. This was in the French department of Haute-Corse, in the northern part of the island of Corsica (in total, there were 575 specimens of various species (poultry and ornamental birds). The birds were culled on 15 November, and the garden centre's pet facility is now closed. Epidemiological investigations are ongoing.
Since our last report on 17 November, in Germany there have been 70 further reports of HPAI H5N8 in wild birds. While the majority of outbreaks continue to be in the north, and primarily in South Jutland, isolated cases have been identified further south, through Prignitz (in north-west Brandenburg – in a bean goose), Berlin (the federal state, southwest of the city – a greylag goose), and as far south as Nordsachsen (North Saxony – a mallard duck). There have also been three reports of HPAI H5N5 in wild birds.
Also in Germany, three outbreaks of HPAI H5N8 were reported in poultry. One was a premises of 1339 birds (fattening geese, hens and ducks). The second was a premises of 660 birds (laying hens and fattening geese). The third was a smaller, non-commercial premises of 43 birds (layer hens and turkeys). It is reported on ADNS that following a risk assessment (and in accordance with Council Directive 2005/94/EC) restriction zones for this premises have not been put in place.
Ireland has reported two cases of HPAI H5N8 in wild birds. One was in a mute swan in the north-east (in County Monaghan), and the other a curlew in County Mayo, in Ireland’s north-west.
Italy reported two cases of HPAI H5 in wild birds on 21 November. One was in the province of Venice, where a common teal was shot in a hunting area. The other was in Rovigo province, again in hunted wild birds (wigeons and mallards). The same virus was detected: HPAI H5 viruses belonging to the 2.3.4.4 B clade. The HA sequence surrounding the cleavage site is highly related to that of HPAI currently circulating in Northern Europe. Identification of the NA subtype and characterization of the full genome is in process
Since our last report on 17 November, there have been six further HPAI H5N8 cases reported in wild birds in the Netherlands. Species included mute swans, barnacle geese, and several buzzards. There were four reports of HPAI H5N8 in captive birds (with no details regarding species on ADNS). There was also one report of HPAI H5N5 in wild birds – in a reed (or bean) goose.
Sweden has reported one outbreak of HPAI in poultry on 18 November. This was in a premises containing 5,100 turkeys. On the premises there were two populated sheds, and only the shed containing 1,800 birds displayed symptoms. All birds on the premises were culled.
(SNIP)
Conclusion
As a consequence of the H5N8 HPAI poultry outbreaks in the UK, and in Germany and the Netherlands; as well as the increasing HPAI H5N8 cases in wild birds in the UK, Belgium, Denmark, Germany, Ireland, Italy, the Netherlands and Sweden this week, and the known migration routes on to the UK from these countries: the risk of HPAI incursion in wild birds in the UK is HIGH. The overall risk of infection of poultry in the UK is MEDIUM; although it should be noted that the risk of introduction to individual premises, depends upon the level of biosecurity implemented on farm to prevent direct or indirect contact with wild birds
While the Avian flu action so far has been limited mostly to Europe, the migratory flyways (see map below) that connect Siberia to Western Europe also extend into the Mediterranean, the Middle East, and even Africa. During the 2016-2017 record-setting European avian epizootic, HPAI H5N8 also made its deepest inroads into Africa, and even crossed the Equator into South Africa.
Yesterday the African Union (AU) issued an alert due to the increased bird flu activity in Europe, warning that a fresh round of HPAI could be winging its ways towards the African continent as well.
Highly Pathogenic Avian Influenza (HPAI) H5N8 – Notification
Date/Time: 24 November 2020
Incident/Event title/Name: Highly Pathogenic Avian Influenza (HPAI) H5N8
Notification*: Alert Warning Activation Execution
From AUC Technical Offices: AU-IBAR, AU-PANVAC and Africa CDC
To: AU Member States
1. Situation
Summary: As of 22 November 2020, a highly pathogenic avian influenza (HPAI) H5N8 outbreak in wild birds and poultry has been reported in 12 countries, mainly in western Europe. The virus has been carried across from Southern Russia to Kazakhstan, and now Eastern Europe through migratory birds heading back to their winter feeding grounds primarily in Africa. As these are migratory birds, and even poultry flocks or products, coming into Africa from the affected regions could be carrying the virus, this poses a threat to poultry flock health, farmer livelihoods, and food security on the continent. And while this particular virus has not caused illness in humans to date, the likelihood of a spill-over event that could impact human health should not be ignored.
Background: The HPAI H5N8 virus of concern is of the H5 2.3.4.4.b. clade that has been circulating across Eurasia and into Africa since 2016. The first report regarding this current outbreak came from southern Russian in late July. To date, 12 countries have been impacted: Belgium, Croatia, Denmark, France, Germany, Ireland, Israel, Kazakhstan, Netherlands, Russia, Sweden, and the UK. The species most commonly affected have been wild and domestic fowl (e.g. domestic ducks, geese, chickens, swans).
While the original virus has reassorted with other wild bird influenza viruses to form new strains of H5N5 and H5N1 HPAI virus, no evidence of spillover of this clade into human populations has been detected. However, direct transmission from an infected bird or through another infected animal reservoir, while rare, is possible.
According to World Organisation for Animal Health (OIE) reports, several African countries have reported previous HPAI H5 or H7 outbreaks over the past 5 years. Specifically, all five AU regions and at least 15 AU Member States have been impacted (Table 1). Nigeria and South Africa are the only two countries reporting ongoing H5 outbreaks this year.
While this year's outbreak hasn't reached anywhere near the levels we saw in 2016-2017, it is gaining momentum, and is well worth our attention.
