rapid risk assessment on incursion of hpai (predominantly ... · improving biosecurity measures and...

Rapid risk assessment on incursion of

HPAI (predominantly H5N8) into

housed or not housed poultry flocks

and captive birds

01 March 2021

Situation as at 01 March 2021

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Contents

Summary ......................................................................................................................... 4

Introduction ..................................................................................................................... 6

Hazard Identification ........................................................................................................11

Previous outbreaks of HPAI H5N8: ......................................................................................13

Current Situation..............................................................................................................13

Risk Question...................................................................................................................15

Risk Levels ...................................................................................................................15

Entry Assessment .........................................................................................................16

Exposure Assessment........................................................................................................18

Domestic poultry ..........................................................................................................20

Captive birds ................................................................................................................21

Ratites ........................................................................................................................22

Game birds ..................................................................................................................22

Consequence assessment ..................................................................................................23

Conclusions .....................................................................................................................23

Assumptions and Uncertainties ..........................................................................................25

References ......................................................................................................................25

Annex 1 ..........................................................................................................................26

Annex 2 ..........................................................................................................................36

Annex 3 ..........................................................................................................................37

Annex 4 ..........................................................................................................................40

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Summary

This is an update of a rapid risk assessment last updated on 26 January 2021. It was

first produced on 09 November 2020 in response to findings of highly pathogenic

avian influenza (HPAI) H5N8 in poultry (on 02 November 2020) and wild birds (09

November 2020). All updates made on 01 March 2021 are shown in red for ease of

reference.

1. In October 2020 the risk of AI H5N8 incursion through migratory wild waterfowl

was increased to MEDIUM on the basis of outbreaks in north-west Europe.

2. The report of HPAI H5N8 in a broiler-breeder rearing unit flock in Cheshire (AIV

2020/02) on Monday 2 November was the first confirmed event of HPAI H5N8 in GB

since 2017. Two wild geese tested positive for HPAI H5N8 in south-west England on

09November 2020. The risk of AI H5N8 incursion through movements of migratory

wild waterfowl was increased to HIGH on 6 November 2020 and then to VERY HIGH

in early December.

3. When this risk assessment was last updated on 26 January 2021, HPAI H5N8

had been detected at 15 premises in England (poultry and captive birds); 1 poultry

premises in Scotland; 2 poultry premises in Northern Ireland, with one outbreak of

HPAI H5N1 confirmed in poultry in England. There had been 299 wild bird findings of

HPAI H5 in England, Wales, and Scotland in a range of wild bird species, including

migratory birds, resident birds and bridging species (9 in Northern Ireland). The

majority of these were HPAI H5N8. Numbers of wild waterfowl to overwinter in the

UK peaked in January 2021. Therefore, as a result of ongoing infection pressure the

risk of AI H5N8 incursion in wild birds was maintained at VERY HIGH in January

2021, and the risk of exposure of poultry across the whole GB was assessed to be

MEDIUM (where stringent biosecurity is applied) and HIGH (where biosecurity is

sub-optimal).

4. The total number of positive wild birds detected in addition to the detection of

multiple H5 HPAI subtypes in the same epidemic event is unparalleled in the UK. As

of 01 March, there have been 310 wild bird findings of HPAI H5 in wild birds, with no

new positive samples identified since 01 February. Of these, most were reported in

England with only a few in Scotland, Wales, and Northern Ireland. Of the wild bird

samples that have tested positive to date, these have mainly been in indigenous bird

species; of 310, 177 cases were reported in mute swans.

5. Wild bird infection pressure is decreasing. The migratory wild waterfowl

population is significantly reduced, and the frequency of wild bird cases is reduced.

Bridging species still play a role in fomite spread, but this is also decreasing as

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environmental contamination decreases. Therefore, the risk of AI H5N8 incursion in

wild birds has been reduced to MEDIUM (from VERY HIGH).

6. As of 01 March, the total number of HPAI outbreaks in poultry and/or captive

birds in the UK to 01 March, is 22. HPAI H5N8 has been identified in poultry in

England (14), Northern Ireland (2), Scotland (1), game birds in Wales (1), and

captive birds in England (2). HPAI H5N1 has been identified in poultry and game

birds in England (1) and Scotland (1). The most recent of these, where HPAI H5N1

was reported on 11 February, was in Scotland in a game bird rearing and breeding

premises. Given a decreasing wild bird infection pressure, decreasing environmental

contamination, we consider the risk of exposure of poultry across the whole GB to be

MEDIUM. (Risk level is reduced from HIGH, where biosecurity is sub-optimal, to

MEDIUM, where stringent biosecurity is applied.) A medium risk level covers a wider

spread of risk than at high or low, so for locations where biosecurity is suboptimal the

risk level will be higher within the medium band than where biosecurity is good.

7. An Avian Influenza Prevention Zone (AIPZ) is in place, and personnel should

be taking additional biosecurity measures. An AIPZ was declared in England, Wales

and Scotland, with additional housing measures that came into force from 14

December 2020. This means all bird keepers in GB (whether they have pet birds,

commercial flocks or just a few birds in a backyard flock) are required by law to take

a range of biosecurity precautions, including housing their birds (except in very

specific circumstances). Any legal requirements to house and take biosecurity

measures should be kept under review and adapted as needed to reflect emerging

evidence, including levels of compliance with housing and biosecurity measures and

the disease picture across Europe. Under some circumstances, it will not be possible

to house poultry, captive birds and breeding game birds, whether for practical or

welfare reasons relating to their husbandry needs, and so housing will not be

universally achieved.

8. An EFSA analysis of the 2016/2017 HPAI H5N8 epidemic concluded that

housing birds gave a two-fold reduction in risk of virus incursion into poultry houses.

However, other measures were also effective (preventing wild bird contact and

improving biosecurity measures and education). In order to be effective, housing

must be accompanied by thorough biosecurity measures to prevent the disease from

being introduced to the poultry through contaminated fomites (e.g. human

behaviours producing spread) or by other items that are taken into or enter the

housing.

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Introduction

Across Northern Europe, Russia, and the Middle East since September 2020, HPAI

H5N8 infection has been detected in multiple species of wild bird, sometimes prior to

the detection of the same virus in various types of domestic poultry. In August and

September, cases in wild birds and outbreaks in poultry were reported in Russia and

Kazakhstan; as well as in Israel in September. The first report in Europe was on 16

October in a Eurasian wigeon in the Netherlands.

In early November a rapid risk assessment was undertaken to address the risk of

incursion of H5N8 HPAI into housed and non-housed birds (domestic poultry and

captive birds) from contact with migratory wild waterfowl from Europe during the

2020/2021 winter season. This was reviewed on 26 November 2020 and on 26

January 2021.

Two migration pathways contributed to infected wild waterfowl flying out of central

Russia/Kazakhstan. The first is the Black Sea Mediterranean pathway which

contributed to reported cases in the Middle East (Israel) as birds fly to Africa in

October. European countries along this route would include those in Central and

South-eastern Europe. The second is the East Atlantic route which contributed to

cases in the North European countries, particularly Scandinavia, Germany,

Denmark, Poland, Ireland and GB. There are no clear boundaries between these

migration routes and birds using each will mix in the shared breeding grounds.

Multiple waterfowl species may be found at the same breeding ground sites and at

the same wintering sites. The numbers of HPAI H5Nx cases in wild birds and captive

birds reported in Europe in the week commencing 01 March 2021 are presented in

Table 1.

Table 1: Current outbreaks of HPAI H5Nx in domestic poultry and captive birds

and cases in wild birds (26 January to 19 February), according to official

reporting sources. (Annex 3 lists the wild bird species involved in these reports).

Country

H5 H5N1 H5N3 H5N4 H5N5 H5N8

Total

Poultry

Wild/

Captive

Birds

Wild/

Captive

Birds

Wild/

Captive

Birds

Wild/

Captive

Birds

Poultry

Wild/

Captive

Birds

Poultry

Wild/

Captive

Birds

Austria

2

4 6

Belgium

1

1

2

7

Country


Total

Poultry

Wild/

Captive

Birds

Wild/

Captive

Birds

Wild/

Captive

Birds

Wild/

Captive

Birds

Poultry

Wild/

Captive

Birds

Poultry

Wild/

Captive

Birds

Bulgaria 4

4

Czech

Republic

4

4

Denmark

1

1 36 38

Finland

2 2 4

France

1

11 1 13

Germany

3 1

4 10 48 66

Hungary

3

3

Ireland

4 4

Italy

1 1

Latvia

4 4

Luxembourg

4

4

Netherlands

1

1

Norway

3 3

Poland

1 12 3 16

Romania

3

3

Russia

1 1 2

Spain

1 1

Sweden

1

1 2

Switzerland

2

2

8

Country


Total

Poultry

Wild/

Captive

Birds

Wild/

Captive

Birds

Wild/

Captive

Birds

Wild/

Captive

Birds

Poultry

Wild/

Captive

Birds

Poultry

Wild/

Captive

Birds

Ukraine

3

3

Total 4 1 1 5 3 1 11 51 109 186

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An Avian Influenza Prevention Zone (AIPZ) has been declared in England, Scotland

and Wales (effective from 5pm on the 11 November 2020) with the requirement for

additional housing measures in force from 14 December 2020. This means all bird

keepers (whether they have pet birds, commercial flocks or just a few birds in a

backyard flock) are required by law to take a range of biosecurity precautions,

including housing their birds (except in very specific circumstances). Elsewhere, a

housing order has been put in place in the Netherlands, southern Norway and in the

north German state of Schleswig-Holstein. In Italy, a housing order for poultry was

established in high risk areas in October 2020; this was expanded nationwide at the

end of November. In Denmark, from November 2020, birds (excluding ducks and

geese) should be kept inside, although if area is less than 40m2 need only be

“protected from entry of wild birds”. The Hungarian CVO has enforced “closed

keeping of birds”. Ireland introduced housing measures for poultry and captive birds

on 21st December 2020 (PAFF, 2021). The orders may cover just certain sectors of

commercial poultry and certain high risk areas. In the epizootic of 2016/2017, many

EU MSs put in place a housing order.

The effectiveness of a housing order is difficult to assess. In 2016/2017 it is possible

there would have been a higher number of outbreaks without an order in place;

however, in France, Germany and Hungary, countries with the highest number of

outbreaks and with housing orders in place, there was secondary spread, indicating

poor biosecurity in some sectors, rather than primary contact with wild birds per se.

Last year, the EU warned that secondary spread between establishments keeping

anseriforme species was observed (PAFF, 2020).

EFSA carried out a comprehensive review of the outbreaks of HPAI H5N8 in

2016/17 to assess the risk of introduction into poultry from migratory and residential

wild birds (EFSA, 2017). The opinion concluded that once virus is introduced to a

wild bird population, a critical population size is required before virus amplification

and further wild bird-associated geographical spread of the virus can take place.

Therefore, there is an increased likelihood of incursion into poultry farms most

closely located to large gatherings of wild birds (including but not exclusively

waterfowl) of target species1 during the migration season. Once the migratory birds

leave (from March onwards usually) the risk of incursion usually reduces but in cases

in which non-migratory birds are still testing positive, there will be a continual, albeit

lower, risk.

The opinion also concluded that the relative risk reduction for entry is three fold by

preventing access to water bodies, that housing gives a further two fold reduction,

1 The list of target species is available in Annex II Part 2 of Commission Decision 2010/367/EU on the implementation by Member States of surveillance programmes for avian influenza in poultry and wild birds.

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and by applying routine biosecurity there is a further four fold reduction in risk while

high biosecurity is a 44 fold reduction in risk.

The opinion recommends that the following biosecurity measures for housed birds

which should be applied are: separating from wild birds; separate waterfowl from

gallinaceous poultry; provide potable drinking water; implement a hygiene lock for

each poultry house and provide biosecurity training to all personnel. For non-housed

birds, it was recommended to restrict access to birds for people and provide

biosecurity training to personnel as the most feasible and sustainable measures. At

all times, feed must be provided indoors only, wild bird access should be restricted;

and contacts with other poultry premises limited. Feed and water could be provided

under a roof or a horizontal fabric for non-housed birds. The opinion used expert

knowledge elicitation to gather evidence on the biosecurity measures and a lack of

biosecurity awareness in the staff on sites was commonly reported.

A further supporting document to EFSA opinions on the risk of introduction of HPAI

into poultry farms in general (EFSA, 2017a) was a systematic review of previous

outbreaks to identify risk factors and concluded that the main risk factor for

introduction is contact with wild birds or fomites contaminated with wild bird faeces.

Other important risk factors were poultry species (waterfowl and turkeys are higher

risk); production system, where outdoor systems are higher risk than indoor; and

presence of biosecurity flaws.

This rapid risk assessment is aimed at providing advice around the most appropriate

form of prevention zone order for the different sectors and establishing a body of

evidence to help make decisions around mandatory housing.

Under article 6(1) of the Avian Influenza and Influenza of Avian Origin in Mammals

(England) (No 2) Order 2006 (“the Order”), the Avian Influenza and Influenza of

Avian Origin in Mammals (Scotland) Order 2006 and the Avian Influenza and

Influenza of Avian Origin in Mammals (Wales) (No 2) Order 2006, the Secretary of

State must carry out a risk assessment in order the declare an Avian Influenza

Prevention Zone.

Measures to reduce the risk of transmission of avian influenza

6.—(1) If, after carrying out a risk assessment, the Secretary of State considers such action necessary to reduce the risk of transmission of avian influenza to poultry or other captive birds from wild birds or from any other source, he must—

(a) declare an avian influenza prevention zone in all or part of England/Scotland/Wales; or

(b) serve or require an inspector to serve a notice on the occupier of any premises where poultry, other captive birds or any categories of poultry or captive birds specified in the notice are kept.

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(2) A declaration or notice under paragraph (1) must impose such measures as the Secretary of

State considers necessary to reduce the risk of transmission of avian influenza.

(3) When deciding the measures to impose under paragraph (2), the Secretary of State must consider whether measures are necessary—

(i) to prevent direct or indirect contact which wild birds might otherwise have with poultry and other captive birds;

(ii) to reduce the risk of feed and water provided to poultry and other captive birds being contaminated with avian influenza virus; and

(iii) to reduce the risk of the spread of avian influenza between premises.

(4) The power of the Secretary of State to impose measures by declaration or notice under this article includes the power—

(a) to require poultry and other captive birds to be housed or otherwise kept separate from

wild birds;

(b) to require poultry or other captive birds or categories of such birds specified in the

declaration or notice to be housed or otherwise kept separate from other poultry and captive

birds;

(c) to require that poultry and other captive birds are provided with feed and water to which

wild birds have no access;

(d) to require keepers of poultry and other captive birds and others who come into contact

with such birds to cleanse and disinfect their footwear and take such other biosecurity

measures as a veterinary inspector or an inspector under the direction of a veterinary

inspector may require;

(e) to ban or limit the collection of poultry or other captive birds at any fair, market, show,

exhibition, race or other gathering;

(f) to ban or limit the use of birds of the orders Anseriformes (including ducks, geese and

swans) and Charadriiformes (including gulls, murres, terns, avocets, puffins, woodcock,

oystercatchers, sandpipers, plovers, surfbirds, snipes and skimmers) as decoys during bird

hunting.

Hazard Identification

The hazard identified is the avian influenza virus, predominantly HPAI H5N8, but

other virus subtypes have been detected including H5N1, H5N2, H5N3 and H5N5.

Viral material has been detected, and where viable samples submitted, virus has

been isolated from poultry report cases (outbreaks) and wild birds in the UK during

the current epizootic, at the World Animal Health Organisation (OIE) and Food and

Agriculture Organisation (FAO) International Reference Laboratory (IRL) for Avian

Influenza (AI) at the Animal and Plant Health Agency (APHA). The IRL have utilised

frontline molecular assays and whole genome sequencing techniques to define the

genetic composition of the causative agent.

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The virus from the GB outbreaks maps across the whole genome with the H5N8

viruses (reported by the laboratory as part of an international collaboration) found

elsewhere in Europe (multiple countries), Middle East and Central Asia (including

Russian Federation and Kazakhstan) during the last 6 months.

Importantly, despite the detection of numerous different H5Nx isolates, the

haemagglutinin (HA) gene is highly conserved (amongst isolates characterised from

the 2020/21 epidemic to date) and all H5 HAs detected cluster within the same

clade, designated as clade 2.3.4.4b. This is important as the composition of

haemagglutinin gene underpins fundamental virus properties such as infectivity and

transmissibility. Certainly, the topology of the phylogenetic tree for the HA gene

indicates that all UK report case isolates detected during Autumn/Winter 2020/2021

(including 17 H5N8 and 1 H5N1) cluster within clade 2.3.4.4b alongside all European

isolates for which sequence is available. These viruses also cluster with H5N8,

H5N5 and H5N1 HPAI viruses from the across the EU, and Russia, again within

clade 2.3.4.4b. Interestingly, the H5N1 viruses from the UK and EU cluster together

whilst the UK H5N5 and H5N8 viruses group together on the HA phylogenetic tree

as a main Autumn/Winter 2020 cluster. All Autumn/Winter 2020 detected viruses

cluster separately from the H5N8 viruses responsible for the outbreaks in Europe in

late 2019- early 2020. Specifically, the HA gene appears to descend from the HPAI

H5N8 viruses which caused the previous epidemic wave that caused outbreaks

across the Eurasian and African continent in 2017-2018, and is highly related to the

H5N8 viruses which have been circulating in Egypt since 2017 with the closest

genetic linkage being an isolate detected in Iraq in May 2020.

In contrast, the genetic signatures of the three H5N1 viruses are almost identical and

cluster together across all genes. These isolates are postulated to result from

multiple reassortment events with LPAI viruses circulating in wild birds in Eurasia,

from which they have acquired six (PB2, PB1, PA, NP, NA and NS) out of eight gene

segments. Whether this reassortment event has occurred in Europe or Asia is an

issue that cannot be assessed from the data available to date.

Wild bird cases in England, Wales, and Scotland have tested positive for HPAI

H5N1, H5N5, and H5N8. The detection of three H5 HPAI subtypes in the same

epidemic event is unparalleled in the UK or indeed at European level. All these

viruses are genetically closely related through their haemagglutinin gene, which is

the key viral gene influencing pathogenesis, host range, transmission, and host

immunity. Continued virus evolution by either genetic shift (reassortment) or genetic

drift (accumulation of mutations in a single genome segment) in wild birds is not

unexpected, although to date evidence for either process is minimal.

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Previous outbreaks of HPAI H5N8:

In 2014/2015 several outbreaks of H5N8 HPAI were detected in poultry in Europe

(Germany, Italy, Netherlands and GB) all in housed birds and were attributed to

indirect contact with infected wild waterfowl. In the Netherlands, there were four

separate incursions and two were linked premises. In Germany, there were just two

separate introductions and, in both Italy and GB (England), only single premises

were affected. No direct links were found between the different countries. Wild

waterfowl testing positive for H5N8 HPAI were only detected in Netherlands and

Germany, in Eurasian wigeon and teal, after the outbreaks had been notified. No

significant wild bird mortality was observed in 2014/2015.

In the HPAI H5N8 2016/2017 epizootic, virus spread rapidly in migratory and non-

migratory wild waterfowl in Europe causing mortalities in these birds. This was

strikingly different to previous years and indicated a change in the virus pathogenicity

for certain species of bird. By the end of the season most EU countries, as well as

Europe, the Middle East and parts of southern and west Africa had reported cases of

this virus.

Current Situation

There is currently a lack of evidence for whether some species of wild waterfowl are

asymptomatically infected with this virus strain and whether the virus can continue to

circulate silently or with minimal clinical disease in non-migratory, sedentary birds.

However, considering the number of birds found dead in non-breeding sites across

Europe (in the hundreds) compared to the total number of birds in these sites (likely

to be in the many thousands), it is feasible that the virus is circulating widely with low

mortality (see Map 1).

This pattern of geographical distribution follows that seen for the epizootic of H5N1

HPAI in 2005/2008 in Europe, and in H5N8 HPAI in 2016/2017 in Europe. In those

years, spread occurred along a similar route of migratory wild waterfowl causing wild

bird die-offs in North and Central Europe (see maps 2 and 3). Therefore, the

2020/2021 epizootic is following a similar pattern of transmission in wild birds and

spill-over into domestic poultry as was observed with HPAI H5N8 in 2016-2017, and

H5N1 HPAI in 2005 – 2008 and it can be expected that the current H5N8 HPAI

epizootic will continue to cause issues with the poultry sector for several months to

come, as the virus continues to circulate in both migratory and non-migratory

waterfowl in Europe.

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Map 1: Current outbreaks and wild bird cases of H5N8 HPAI (as of 19

February). OIE ongoing outbreak data is only available until 19 February.

Map 2: Outbreaks and wild bird cases of HPAI H5N8 in Europe in 2016-2017

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Map 3: Outbreaks and wild bird cases of H5N1 HPAI in Europe, North Africa

and the Middle East in 2005-2008

Risk Question

What is the risk of incursion of HPAI (predominantly H5N8, but other virus subtypes have

been detected including H5N1, H5N2, H5N3 and H5N5) into housed and non-housed birds

(domestic poultry and captive birds) from contact with wild birds (resident species and

migratory wild waterfowl) during the 2020/2021 winter season?

Risk Levels For the purpose of this risk assessment, the following EFSA-derived definitions will

be used:

Negligible So rare that it does not merit to be considered

Very low Very rare but cannot be excluded

Low Rare but does occur

Medium Occurs regularly

High Occurs very often

Very high Events occur almost certainly

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Entry Assessment

The wild waterfowl population in GB is relatively well understood. Several NGOs

conduct regular surveys for the wild waterfowl at known wintering and breeding sites

across GB. In particular, the British Trust for Ornithology (BTO), the Royal Society

for the Protection of Birds (RSPB) and the Wildfowl and Wetlands Trust (WWT) carry

out counts of wild birds. Their evidence shows the sites of the largest waterbird

aggregations in GB (see Figure 1). The Wash is one of the premier sites for

wintering waterbirds in GB with over 300,000 birds counted each year, while other

top ten sites include the Somerset levels, the Dee estuary, the Humber estuary and

the Ribble, Alt and Mersey estuaries, but there is a variation of at least 10% from one

year to the next, attributed to the winter weather conditions. There are 53 sites with

at least 20,000 birds wintering year after year across GB.

Figure 1. Wild bird assemblage abundance in GB, derived from 109 species

considered most relevant for the transmission of AI to poultry flocks. (From

Hill et al. (2019) Scientific Reports 9:19973)

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In terms of migration, wild waterfowl arrive in GB from Northern Europe from August

and numbers generally peak in December to January. Annexe 2 gives estimated

numbers of wild birds entering the UK during this period (Flutest project, 2014).

While some species, such as swans, will be site loyal from one year to the next,

others will be less so, and there will be mixing between species in the large

aggregation sites.

Outward migration has already started and, as this year appears typical of an

‘average’ spring season, it is most likely that a substantial proportion of the migratory

birds will have left the UK by the end of March if the warm weather continues here

and there is no extreme cold weather event in continental Europe. In this respect,

the UK may differ from northern European member states in that the winter

populations of some species here will vanish, or diminish considerably, as a

consequence of eastwards migration to breeding sites. In contrast, substantial

populations of these same birds will continue for some weeks in European countries

at traditional aggregation sites along the North Sea and Baltic coasts which form part

of the eastwards flyway, representing winter migrants leaving European sites slightly

later, as well as migrants from the UK and western areas joining them at stop-over

sites. At this point in the outbreak, reports of cases in wild birds and outbreaks in

poultry in Europe are likely to continue for longer than in UK, given a higher ongoing

infection pressure in northern and central Europe.

There is evidence that resident birds (species which breed here and can be relatively

sedentary) have also been infected, may continue to circulate viruses and

consequently act as an ultimate source of infection to livestock. However, changes

in their behaviour may also reduce this risk, as birds make regional or

neighbourhood scale movements from moderate aggregations on larger waters into

smaller groups at their breeding sites on small waterbodies. This change in

population structure and contact behaviour ought to reduce the circulation of virus

(as was experienced in 2016/17).

There is a system for wild bird surveillance in GB, whereby found dead birds from

target species are reported either by wardens at reserves and wetland sites, or by

the public for testing at the NRL. As of 01 March 2021, there were 310 wild bird

positive findings of H5 in England (276), Wales (6), Scotland (19) and Northern

Ireland (9). 284 submissions tested were subtyped as H5N8, ten submissions were

H5N1, six submissions were H5N5, one submission was H5N3 and nine

submissions were H5Nx (as unidentifiable H5 subtypes). The total number of

positive wild birds detected, in addition to the detection of multiple H5 HPAI subtypes

in the same epidemic event, is unparalleled in the UK. HPAI H5N8 virus has been

identified in a range of wild bird species (both migratory and resident birds), with

18

mute swans, greylag geese and Canada geese representing the majority of

detections. These species are listed in Annex 4.

Bridging species include several resident populations, such as various gulls (e.g.

Herring gull) and corvids (e.g. Eurasian magpie), with some testing positive for HPAI

H5N8 both here and on the Continent (Annex 3 & 4). These species are

distinguished by their propensity to scavenge potentially infected carcases, habit of

aggregating into large groups in winter (gulls often night roost in very large

aggregations on waterbodies along with wildfowl; corvids in substantial mixed

species assemblages in trees) as well as their boldness and habit of exploiting farms

for forage. Corvids and especially gulls are also mobile and may cover significant

distances every day between their night roosts, widely separated foraging locations

and loafing sites. As well as representing a potential source of infection (when

diseased), they may also have a role in fomite transmission from areas where there

is environmental contamination. At this stage in the outbreak, bridging species still

play a role in fomite spread, but this is reducing as environmental contamination

decreases.

We therefore consider the likelihood of there being infected wild waterfowl present in

GB is MEDIUM as a country-wide assessment. However, there will be regional

variation, based on the proximity to aggregation sites for non-breeding wild waterfowl

(MEDIUM uncertainty).

Exposure Assessment

There are multiple pathways for the exposure of poultry to notifiable avian diseases

(Defra, 2018).

These include:

• Contact with infected poultry such as live birds, hatching eggs and day old

chicks of poultry

• Contact with live infected wild birds, particularly waterfowl

• Contact with poultry products and by-products of infected poultry,

• Contact with contaminated feed, water, bedding, equipment, vermin or

clothing / footwear of people in contact with infected birds or contaminated

environment.

19

Biosecurity advice which poultry keepers should practise at all times of the year are

focussed on these pathways as there is a constant low risk of incursion from any

notifiable avian disease being introduced into poultry because LPAI viruses circulate

constantly in wild waterfowl. The EFSA report from 2017 used a combination of

systematic review of all poultry outbreaks and expert knowledge elicitation from

members of the poultry sectors. What was clearly stated in the expert knowledge

elicitation was the need to not only implement biosecurity measures which are

feasible and sustainable but also the importance of training poultry workers in what

these measures mean.

Contact with live infected wild birds, particularly waterfowl:

Housing birds will reduce direct contact with wild waterfowl (both residual migrants

and resident species). It will not prevent any of the other pathways through which

disease may enter a poultry premises. Other biosecurity measures will be more

important. The likelihood of contact with wild waterfowl will be dependent on the

number of such species nearby and how attractive the premises are to birds. The

presence within the poultry premises of a pond or open feed bins are two well-known

factors which make direct contact with wild waterfowl more likely for poultry with

access to the outside environment, as well as encouraging bridging species to

regularly visit premises.

Expert opinion is that the virus will retain infectivity in the environment at low

temperatures, at least to 21 days at 4oC and 8.4 days at 20°C. Initial data indicate

that the current H5N8 HPAI virus has extended survival properties when compared

to the 2016 H5N8 virus that had survival properties of 14 days at 4°C and 6 days at

20°C. Ultimately, this suggests that the 2020/21 isolate lasts 50% longer at 4°C and

40% longer at 20°C than the H5N8 characterised in 2016/17. As higher

temperatures, sunlight intensity and day length reduce virus survival, it is probably

too early to say that there has been much environmental decay. Without further

bouts of cold weather, environmental decay will be starting.

As the most likely contact of poultry kept outdoors with wild waterfowl will be in those

areas where there are high concentrations of these species, the likelihood of direct

contact with wild waterfowl or indirect contact with their faeces would be greater for

those poultry establishments in close proximity to, or with sites attractive to, wild

waterfowl. Therefore, where there are no large aggregations of wild waterfowl, the

risk is lower for this particular pathway, but there are still other pathways which could

lead to the introduction of any notifiable avian disease. It is worth reiterating that H7

LPAI viruses which circulate in wild waterfowl, when introduced into housed layer

hens, have been known to mutate into HPAI which is a more disruptive infection to

control, due to the increased size in control zones.

20

Although in the 2016/2017 season, the outbreaks in commercial poultry

establishments in GB were all housed birds, since not all poultry premises

throughout GB were tested, it is not possible to say whether outdoor flocks were

exposed and did not exhibit clinical signs.

Incursion through imported live animals or products:

For the other pathways, contact with other live birds (i.e. trade in poultry, hatching

eggs, day old chicks) will be dependent on the business itself and the commercial

activities. Contact with products or by-products from infected birds will be dependent

on the activities of people entering the premises and bringing such products with

them and it should be noted that swill feeding is not legal. These will not be

addressed in detail for this assessment. However, housing birds will not impact on

this risk.

Contact with contaminated feed, water, bedding, equipment, vermin or clothing /

footwear of people in contact with infected birds or contaminated environment:

Contamination of feed, bedding and water by wild birds can be prevented by

sourcing such products from safe sources and keeping such items in containers

which no wild birds can access. The site can be made less attractive to wild

waterfowl by preventing access to any ponds on site or excluding ponds and pools of

standing water from the range and making sure feeding areas are protected.

Contact with contaminated equipment, footwear and clothing can be prevented by

making sure all personnel in contact with the birds use disinfectants appropriately.

This will be particularly important where birds are housed, as contact with the birds is

more frequent, as feed, bedding and water must be brought into the houses and

birds must be checked for welfare issues or eggs collected from inside the houses.

Visitors to the farm should also be recorded for security and to help tracing

exercises. Other biosecurity practices should be employed to ensure wild birds are

separated from flocks such as feeding birds indoors or under cover, discouraging

wild birds from landing, removing wild bird contamination and draining watercourses,

removing feeders and water stations from the range, ensuring good building

maintenance and regular inspections for signs of wild bird/rodent access. Vermin

control is strongly recommended because rodents act as fomite spreaders.

Above all, the EFSA opinion recommended ensuring all personnel are trained in, and

practise, good biosecurity, regardless of whether birds are housed or not.

Domestic poultry

The GB poultry sector is complex and seasonally variable. There is a requirement for

all poultry keepers in England, Scotland and Wales with more than 50 birds to be

21

registered with the British Poultry Register. For fewer than 50 birds it is voluntary.

Therefore, any data available will not necessarily include the backyard or smallholder

community. In comparison to data available in 2013, the outdoor chicken sector has

decreased from 62% of total holdings to 30% in 2018.

The poultry sector can be designated in the following way with the various

populations according to the 2018 poultry register. The “outdoor” label is only an

estimate and the NCP Salmonella survey estimates the free range population to be

55% of the layer birds and 18% of turkeys.

Poultry Type Number of

Birds

As proportion

of total

population

Number of

holdings

As proportion of

total poultry

holdings

Total Chickens 270986618 85.45% 10125 51.98%

Outdoor

Chickens 33500062 10.56% 5879 30.18%

Layers 47186064 14.88% 5454 28.00%

Broilers 166134899 52.39% 1663 8.54%

Total Turkeys 8462070 2.67% 1069 5.49%

Outdoor

turkeys 1642191 0.52% 443 2.27%

Total ducks 4108083 1.30% 1364 7.00%

Outdoor ducks 981325 0.31% 878 4.51%

Total geese 146332 0.05% 187 0.96%

Outdoor geese 116826 0.04% 125 0.64%

Total CDGT 283703103 89.46% 12745 65.43%

Total Pheasant 23918729 7.54% 4733 24.30%

Total Partridge 9512172 3.00% 2001 10.27%

Total Poultry 317134004 19479

Captive birds

Captive birds, such as those held in collections, zoos or approved bodies are already

semi-housed and should be kept separate from wild waterfowl. For some, this will be

difficult to prevent access to their water environment (penguins, pelicans, flamingos

etc), but it is unlikely it will be possible to house indoors, so every effort should be

made to prevent wild waterfowl access. There were outbreaks in captive birds in

Europe (in zoos) in 2016/2017 and a derogation exists in EU legislation which means

birds may not have to be destroyed, unless they are in contact with the infected

collection.

22

Ratites

Ratites, such as ostriches, cannot be housed on a long term basis. Outbreaks of

closely related H5N8 HPAIV have been reported in commercial ostriches in South

Africa since 2017. Ratites are therefore susceptible to some strains of HPAIV at least

and there has been a case in Germany of an emu showing clinical signs in a zoo and

therefore these birds should also be considered susceptible.

Game birds

The majority of game birds have already been released for the shooting season and

therefore are considered wild birds and outside the scope of a prevention order

around housing. Some will still be kept in pens and could not be housed due to

welfare issues, therefore the pens themselves would need to be netted where

possible to ensure the birds cannot escape and forage locally. Game bird keepers

should use the guidance

https://www.gfa.org.uk/user_files/uploads/Bird_Flu_and_Gamebirds.pdf

Captive birds used as decoys would be at risk of increased contact with wild

waterfowl. If they remain at one place for the duration of the fowling season, then

they will not come into contact with domestic poultry; however, if the birds are moved

around to other sites or spend any time at a premises where domestic poultry are

kept, this is an increased risk for the poultry. It is illegal to release by hand captive

birds for the purpose of being shot immediately after their liberation, under Part 1,

Section 8 of the Wildlife and Countryside Act, 1981.

Given the large poultry population and the proportion which would be outdoor and in

the regions close to the large aggregations of wild waterfowl, we consider the risk of

exposure of poultry across the whole GB to be MEDIUM (MEDIUM uncertainty). A

medium risk level covers a wider spread of risk than at high or low, so for locations

where biosecurity is suboptimal the risk level will be higher within the medium band

than where biosecurity is good. Twenty-two infected premises have been identified

across England, Scotland, Northern Ireland and Wales. Furthermore, HPAI H5N8

(and other subtype combinations) has been confirmed in many wild birds in England,

Scotland, Wales and Northern Ireland. An AIPZ is in place, and personnel should be

taking additional biosecurity measures. The pathways which lead to disease

incursion are not prevented by housing per se, but housing birds is a risk reduction

measure.

https://www.gfa.org.uk/user_files/uploads/Bird_Flu_and_Gamebirds.pdf

23

Consequence assessment

Any outbreak of notifiable avian disease has a significant impact on GB poultry

industry, through the trade and economic impacts on the producer and the sector.

This is the same for any notifiable avian influenza virus. Average costs to

government may be between £2 and £4 million per outbreak, depending on the

number of birds involved and time taken to complete secondary C&D and return to

disease free status.

Housing birds which are not used to housing can cause welfare issues. Making sure

their environment is enriched (e.g. with toys), that they have plenty of room to move,

access to feed and water, clean bedding and the ability to display natural behaviours

are all welfare priorities. For ducks, their bedding must be changed regularly as they

will mess it quickly and they need access to water so they can clean their feathers. If

the birds become stressed, they may be more prone to infections or other

behaviours which impact on welfare. Certain species cannot be housed for welfare

reasons or because they are already considered wild: geese, ratites and gamebirds.

GB is required to deliver surveillance for H5 and H7 LPAI incursions in poultry

(including H5 and H7 HPAI in Anseriformes) under Council Directive 2005/94/EC

and Commission Decision 2010/367/EU. An option for Risk Based Surveillance is

available and has been applied in GB since 2012. The output of the model used for

the risk based targeting of surveillance in poultry identified 2231 10km grid squares

where wild waterfowl and registered poultry flocks are co-located as identified from

2016 “Sam” (APHA’s registration database) and British Trust for Ornithology data.

For these grid squares, a risk score >0 could be assigned and then ranked into 6

bands of equal numbers of grid squares (approximately 373 in each rank) – where

Rank 1 represents the lowest and rank 6 the highest risk. The remaining areas of GB

where no poultry premises were registered have been assigned a “zero risk” score

even though non-commercial poultry may be resident and wild waterfowl abundant.

The actual risk of AI incursion therefore will not be “zero” in these areas.

Conclusions

Housing should only be applied in conjunction with other biosecurity measures, but it

should be noted that it will not be effective if used as a single measure. The trigger

for such an order should be associated with a primary case in wild waterfowl or high

confidence that a poultry outbreak is related to contact with wild birds.

In the current outbreak to 01 March 2021, there have been fourteen outbreaks of

HPAI H5N8 in poultry confirmed on premises in England; one outbreak confirmed on

24

a premises in Scotland; one outbreak confirmed in game birds in Wales, and two

outbreaks confirmed in Northern Ireland. There have also been two reports of HPAI

H5N8 in captive birds in England, one report of H5N1 in backyard chickens, in

England; and one report of H5N1 in gamebirds in Scotland (which was the most

recent of these reported on 11 February).

In GB the sensitivity of our wild bird avian influenza surveillance has been increased

to ensure collection and analyses of any number of targeted species of wild birds

(essentially ducks, geese, swans, gulls and birds of prey) known to carry risk of

infection with AI viruses. Single dead birds of target species where possible will be

collected and tested.

The HPAI H5N8 virus is circulating and established in resident wild waterfowl, as

happened with HPAI H5N1 in 2005-2008, and sedentary wild waterfowl species have

been the majority of wild bird-positive cases. Given the time of year, the higher

survival rate of this particular H5N8 virus in the environment during winter means the

risk of environmental transmission remains, and hence, the continued risk of

secondary spread into indigenous UK wild bird species and naïve non-indigenous

species. Higher environmental temperatures, together with increasing sunlight

intensities are likely to be starting to reduce environmental levels of H5N8 and the

associated risks.

At the beginning of March, migrating waterfowl are leaving the UK with most having

left the UK by the end of March, should current weather conditions continue.

Resident birds will now play a more important role in any residual spread of virus.

Bridging species will play a less important role in onward spread of virus given the

decrease in environmental contamination.

The following conditions will be used to inform when the risk levels will be reduced.

Firstly, the time of year and if our migrant non-breeding waterfowl have left GB;

secondly the period of time that has lapsed since the last reported case, and, if there

is a significant reduction in infection pressure from the Continent; thirdly if the

temperature has started to increase with higher sunlight levels, then the

environmental contamination and transmission would be reduced.

As the housing order has been applied, an exit strategy is now required and this

should also be based both on a risk assessment and other epidemic considerations.

However, an expectation of no wild bird cases could be disproportionate i.e. one

case per week when surveillance sensitivity has been maximised will not correlate

with a very high wild bird risk. The housing order was introduced on the basis of

numerous wild bird cases and several poultry outbreaks and the same criteria in

25

reverse could be used as an exit strategy in addition to using the three scientific

conditions above to inform the risk assessment.

Assumptions and Uncertainties

• The wild bird counts for this year are not known and we are using an annual

assessment based on previous years.

• Other wild waterfowl species (although this assessment considers the most

abundant) may also be important for the transmission of this virus.

• Gulls as both a source of direct infection, or a vector of environmental contamination

remain a potential threat, though considerable uncertainty is produced by their

mobility as well as their behaviour (scavenging infected carcases, aggregating with

wildfowl, exploiting farms for forage)

• The evidence for the economic benefits and dis-benefits of housing birds is not part

of this assessment.

• The 2016/2017 epidemic allowed experts to analyse the likely risk factors leading to

an incursion of avian influenza and while housing birds was assessed as giving a

twofold reduction, other factors such as preventing access to wild birds (three fold)

and improving biosecurity (four fold) are also significant.

• While housing may prevent direct contact with wild waterfowl, it could increase

indirect contact with contaminated environment and the birds may be under stress,

leading to more disease transmission and greater likelihood of viral mutation. Regular

contact with wild birds and their LPAI viruses may produce an environmental

“vaccine” protection against HPAI viruses.

References Defra (2018)

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_da

ta/file/759784/ai-rationale-hras-nov2018.pdf

EFSA (2017) https://www.efsa.europa.eu/en/efsajournal/pub/4991

EFSA (2017a) https://efsa.onlinelibrary.wiley.com/doi/abs/10.2903/sp.efsa.2017.EN-1282

Gale, P. et al. (2014) entry of H5N1 highly pathogenic avian influenza virus into Europe

through migratory wild birds: A qualitative release assessment at the species level. Journal

of Applied Microbiology 116, 1405-1417.

PAFF (2020) https://ec.europa.eu/food/sites/food/files/animals/docs/reg-

com_ahw_20201020_pres_hpai_efsa.pdf

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/759784/ai-rationale-hras-nov2018.pdf

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/759784/ai-rationale-hras-nov2018.pdf

https://www.efsa.europa.eu/en/efsajournal/pub/4991

https://efsa.onlinelibrary.wiley.com/doi/abs/10.2903/sp.efsa.2017.EN-1282

https://ec.europa.eu/food/sites/food/files/animals/docs/reg-com_ahw_20201020_pres_hpai_efsa.pdf

https://ec.europa.eu/food/sites/food/files/animals/docs/reg-com_ahw_20201020_pres_hpai_efsa.pdf

26

Annex 1

Data on migratory waterfowl in Scotland

Wintering sites in

Scotland

Origin HPAI priority

for Scotland

Bewick’s Swan Does not tend to winter

in Scotland. Previously

flew through Scotland

from Netherlands to

Ireland, but less so

now

Western Siberia Very low

Whooper Swan Caerlaverock, grazes

in fields so could

contact poultry

Iceland Very low*

Mute Swan Generally sedentary Very low

Greylag Goose Wintering flocks in

Scotland, but sites in

extreme north and

north-west of Scotland

are occupied by a

resident population.

Greylags feed

exclusively on

agricultural land and

could contact poultry

Non-resident UK

Greylags originate

from Iceland.

Wintering populations

in northern Germany,

Denmark,

Netherlands more

likely to fly to England

in cold weather

Very low

Barnacle Goose Winter in Caerlaverock

(Solway )and also west

coast and islands

South-west Solway

wintering populations

are from Spitzbergen,

while north-west are

from Greenland

Low

Pink-footed Goose Grazes in fields so

could contact poultry,

Loch of Strathbeg

(Aberdeenshire) is

wintering site for 20%

of world population.

Winters around east

coast, central belt and

Solway (Caerlaverock)

breeding grounds in

Spitsbergen, Iceland

and Greenland. UK

birds are from

Greenland, Iceland.

Very low

27

Wintering sites in

Scotland


for Scotland

Bean Goose Rare in UK in general,

site in south-west

Scotland

Northern Eurasia,

Siberia, also eastern

population wintering

in south-east Asia

Very low

Greenland white-

fronted goose

(flavirostris)

West coast of Scotland Greenland Very low

Eurasian white-

fronted goose

(albifrons)

Rare in Scotland Northern Russia and

eastern population

wintering in South-

east Asia

Very low

Lesser white-fronted

Goose

Very rare vagrant Very low

Light-bellied brent

goose (hrota)

East Scotland, Solway,

central belt

Spitzbergen Very low

Light-bellied brent

goose (hrota)

West coast (and

Ireland)

Greenland Very low

Dark-bellied brent

Goose (bernicla)

Common in southern

England, but not in

Scotland

Northern Russia and

eastern population

wintering in South-

east Asia

Very low

Red-breasted Goose Very rare vagrant Very low

Eider Large wintering

population in Scotland,

all round coast, albeit

with 8 sites with counts

exceeding 1,500 birds.

Although, highly

gregarious, not likely to

come in contact with

poultry as sea duck

rarely found away from

coast due to

dependence on

mussels. Very rare

Low

28

Wintering sites in

Scotland


for Scotland

inland, no need for

freshwater

Goosander Largely freshwater

catches salmon and

trout, unlikely to come

in contact with poultry

Goldeneye Diving duck, unlikely to


poultry

Birds from northern

Europe winter in

Scotland

Very low

Eurasian Wigeon Grazes on grass, so

opportunity to come in

contact with poultry.

Although an estuarine

bird, loss of eelgrass

has resulted in switch

to inland grass in

flooded marshy areas.

Largest wintering sites

in England not

Scotland

Some breed in

Scotland, many from

Eurasia

Medium

Common Teal Could come in contact

with poultry. England

has largest numbers

with Loch Leven

having smaller

numbers

Wintering population

drawn from complete

breeding range –

Iceland, northern

Europe, the Baltic

States, and a large

area of the Russian

Federation.

Medium

Northern Pintail

Mallard Main sites are in

England but widely

distributed. Could

come into contact with

poultry

Medium

Gadwall

Tufted Duck Diving duck, unlikely to


Large wintering

population in GB

Low

29

Wintering sites in

Scotland


for Scotland

poultry. British

breeding birds

generally sedentary

during winter. Main site

in Scotland is Loch

Leven.

generally from

eastern parts of

European range

Pochard Diving duck, unlikely to


poultry. Low site fidelity

suggest highly mobile.

Loch Leven is principal

moulting site from end

of June

Wintering birds

originate mainly from

Baltic (62% from

Latvia) and Russia

Low

Greater Scaup Main sites are Solway

Firth, Loch Ryan,

Morray and the

Islands. Diving ducks

feed on mussels,

mainly coastal in

winter, unlikely to

contact poultry

Icelandic birds winter

in north-western

Scotland, those on

east coast from

Fennoscandian and

Russian populations

Low

References

Owen, M. (1980) Wild geese of the World. Batsford

Ogilvie, M.A. (1978) Wild geese. T&AD Poyser

Cramp, S. (1977) Handbook of the Birds of Europe the Middle East and North Africa.

The birds of the Western Palearctic. Volume 1, Ostrich to ducks.

30

Data on migratory waterfowl in England/Wales

The focus is on those birds coming to England/Wales via the Baltic coast

Species Wintering sites in

England

Origin HPAI priority for

England/Wales

Bewick’s Swan Some 9,000 birds

winter in Britain

(mainly England

including south-east

England and central

England) and Ireland

Single population for

north-western Siberia

Medium –

because of small

numbers which

always fly

through the Baltic

Whooper Swan 16,000 birds in Britain

and Ireland, mainly

Scotland. Some sites

in eastern, northern

England such as

Welney WWT in

Norfolk.

Mainly from Iceland.

Very few of the

Russian and Fenno-

Scandinavian

breeding population

come as far as

England even in cold

weather, normally

winter in the Baltic

Very low –

because not from

Baltic

Mute Swan Generally sedentary

in Britain, Ireland and

importantly in the Low

Countries

Very low because

does not migrate

from Low

Countries, hence

Mute Swan cases

in NL are not a

concern

Graylag Goose Wintering flocks in

Scotland, but sites in

extreme north and

north-west of Scotland

are occupied by a

resident population.

Greylags feed

exclusively on

agricultural land and

could contact poultry

Non-resident UK

Greylags originate

from Iceland.


in northern Germany,

Denmark,

Netherlands more

likely to fly to England

in cold weather

Very low

Barnacle Goose Mainly winter in

Scotland and northern

Ireland. Wild birds are

rare in England,


are from Spitzbergen,

while north-west are

from Greenland. A

Very low

31


England


England/Wales

although there are

feral flocks

small number of

Russian birds which

winter in the

Netherlands could

come over to south-

east England in

severe weather.

Pink-footed Goose Grazes in fields so

could contact poultry.

Mainly East Anglia

and Lancashire.

UK birds are from

Greenland, Iceland

while Spitzbergen

breeding population

winters in Denmark,

West Germany and

the Low countries,

with a few reaching

Britain in severe

winters.

Low risk due to

small numbers

coming from

Denmark,

Germany in

severe winters,

presumably

south-east or

east coast of

England.

Bean Goose Rare in UK in general,

small numbers

wintering at sites in

East Anglia but not

many

Northern Eurasia,

Siberia, Finland

100,000 pairs breed

in western Siberia

Very low because

of low numbers in

England.

Greenland white-

fronted goose

(flavirostris)

Rare winter visitors to

England, a few winter

in Wales

Greenland Negligible

Eurasian white-

fronted goose

(albifrons)

Baltic-North Sea

group winters in the

Netherlands, Belgium,

England and Wales. In

England winters in the

selected sites in the

south (Severn

Estuary, Kent, East

Anglia)

Breeds in northern

Russia, Novoya

Zemlya and Kanin

Peninsula

Medium, comes

through the Baltic

to England each

year but not a

common bird.

Lesser white-fronted

Goose

Very rare vagrant, one

or two birds in

England each year,

most winter in the

Balkans

North Scandinavia,

western Siberia

Negligible

32


England


England/Wales

Light-bellied brent

goose (hrota)

Very small numbers in

England/Wales, more

in Ireland

Spitzbergen and

Greenland

Negligible

Dark-bellied brent

Goose (bernicla)

Common in coastal

sites and marshes in

southern England. Not

common inland or on

lakes.

Northern Russia and

eastern population

wintering in South-

east Asia

Medium risk of

H5N8 entry and

highly gregarious,

but unlikely to

contact poultry

because coastal.

Red-breasted

Goose

Very rare vagrant Very low

Shelduck Many resident in

England but some

migrate to moult in

tidal mud flats in north

Germany in July

Breeding population

returns back from

moult migration to

breeding range in

Britain

October/November

Medium risk of

entry of H5N8 but

generally

coastal/estuarine

bird.

Eider Winter around south

and east coast of

England although less

common than in

Scotland. Although,

highly gregarious, not

likely to come in

contact with poultry as

sea duck rarely found

away from coast due

to dependence on

mussels. Very rare

inland, no need for

freshwater

Relatively small

movements, rarely

over 200 km.

Very low

Goosander Largely freshwater

catches salmon and

trout, unlikely to come

in contact with poultry.

Winters in sites across

UK although

uncommon and many

Males summer moult

in north Scandinavia.

Breeders in Russia

and Fenno-

Scandinavia migrate

west to Baltic and

yeyond to

Very low

33


England


England/Wales

from breeding sites in

Scotland.

Netherlands and

Britain.

Goldeneye Diving duck, unlikely

to come in contact

with poultry with

wintering sites across

England.

Birds from northern

Europe, Russia winter

in the Baltic,

Denmark,

Netherlands and

Britain.

Low

Eurasian Wigeon Grazes on grass, so

opportunity to come in

contact with poultry.

Although an estuarine

bird, loss of eelgrass

has resulted in switch

to inland grass in

flooded marshy areas.

Bird is gregarious with

large wintering sites

across much of central

England.

Some 200,000 pairs

breed in western

Russia and 80,000

pairs in Finland.

Migrate through the

Baltic to winter in west

and south-west

Europe including

Germany,

Netherlands, France,

Britain and Ireland.

High

Common Teal Graze on grass and

could come in contact

with poultry. England

has large numbers

with wintering sites

across England. Bird

is gregarious.

Breeding birds from

north Russia,

Scandinavia, Baltic

States, north Poland,

north Germany and

Denmark fly south-

west in the autumn to

wintering grounds in

the Netherlands and

Britain. Winter

distribution between

Netherlands, England,

Wales and Ireland

greatly dependent on

weather; cold spells

cause immediate

westward movement.

High

34


England


England/Wales

Northern Pintail Scattered sites across

England.


in Britain (no risk) but

some from north-west

Russian, Finland and

Baltic States fly west

to winter in

Netherlands and

Britain, with

movement from the

Netherlands to Britain

in hard weather.

Low due to

smaller numbers

than other ducks

Mallard Many are resident in

UK. Many sites are in

England and widely

distributed. Could

come into contact with

poultry


in Britain (no risk) but

some from north-west

Russian, Finland,

Baltic States and

northern Germany fly

west to winter from

Denmark to north

France and in Britain.

Medium but

reduce to low

because bird is

not gregarious

Gadwall Many resident in

England and also

wintering sites mainly

in England.

Breeders in Germany,

Poland, and west

central Russia winter

in the Netherlands

and Britain.

Medium

Shoveler Many wintering sites

across England. Filter

feeder so restricted to

water unlikely to feed

in fields. Bird is

gregarious.

Breeders from Fenno-

Scandinavia and

Russia migrate west

and south-west to

Netherlands, Britain

and Ireland.

Medium because

although water-

feeder could

infect other

gregarious

waterfowl species

which feed in

fields.

Tufted Duck Diving duck, unlikely

to come in contact

with poultry although

highly gregarious.

British breeding birds

generally sedentary

during winter, and

Large wintering

population in GB

generally from

eastern parts of

European range,

Medium risk of

entry because

although diving

duck could infect

other gregarious

waterfowl species

35


England


England/Wales

many wintering sites

across England.

Russia and

Scandinavia.

which feed in

fields.

Pochard Resident population

but also many

wintering sites across

England and Wales.

Diving duck, unlikely

to come in contact

with poultry but highly

gregarious and may

infected other species.

Low site fidelity

suggest highly mobile.

Wintering birds

originate mainly from

Baltic (62% from

Latvia) and Russia

Medium risk of

entry because

although diving

duck could infect

other gregarious

waterfowl species

which feed in

fields..

Greater Scaup Mainly marine with a

few coming to inlake

lakes. Diving ducks

feed on mussels,

mainly coastal in

winter, unlikely to

contact poultry

Birds on east coast of

England from

Fennoscandian and

Russian populations

Low because

although highly

gregarious less

likely to contact

freshwater ducks.

References

Owen, M. (1980) Wild geese of the World. Batsford

Ogilvie, M.A. (1978) Wild geese. T&AD Poyser

Cramp, S. (1977) Handbook of the Birds of Eurpe the Middle East and North Africa.

The birds of the Western Palearctic. Volume 1, Ostrich to ducks.

36

Annex 2

Numbers of migratory birds (per year) entering GB, the Netherlands and Italy

calculated as the difference between totals of monthly counts (maximum -

minimum), taken from Flutest project work underpinning Gale et al. (2014).

HRS Bird Species GB, Wetland

Bird Survey

data of Austin

et al. 2008

The Netherlands (Hustings et al. 2008)

Italy, peak national

count in January

between 1990 and

2005. Atkinson et al.

(2006)

Bewick’s Swan Cygnus

columbianus

3,775 13,000 0

Whooper Swan Cygnus

cygnus

7,428 2,000 0

Mute Swan Cygnus olor 11,542 5,000 3,248

Greater White-fronted

Goose (European race)

Anser albifrons albifrons

1,341 600,000 11,049

Greylag Goose Anser

anser

72,980 150,000 5,392

Red-breasted Goose

Branta ruficollis

4 7 4

Eurasian Wigeon Anas

penelope

324,097 600,000 123,936

Common Teal Anas

crecca

126,498 50,000 97,529

Mallard Anas

platyrhynchos

97,872 180,000 208,000

Northern Pintail Anas

acuta

25,344 20,000 12,781

Garganey Anas

querquedula

38 (May) + 47

(Aug)*

80 (Apr) + 110

(Aug)*

223

Northern Shoveler Anas

clypeata

11,200 10,000 22,811

Common Pochard

Aythya ferina

24,160 45,000 42,189

Tufted Duck Aythya

fuligula

46,429 150,000 7,725

Black-headed Gull

Larus ridibundus

150,555 150,000 217,468

*Spring and autumn migration

37

Annex 3

Species list for cases in wild birds (as of 7 am on 25/01/2021), according to

OIE.

Country Wild bird species affected

Belgium Canada Goose (Branta canadensis)

Common Wood Pigeon (Columba palumbus)

Egyptian Goose (Alopochen aegyptiaca)

Eurasian Curlew (Numenius arquata)

Eurasian Magpie (Pica pica)

European Herring Gull (Larus argentatus)

Great Crested Grebe (Podiceps cristatus)

Greater White-fronted Goose (Anser albifrons)

Greylag Goose (Anser anser)

Mute Swan (Cygnus olor)

Pink-footed Goose (Anser brachyrhynchus)

Czech Republic Mute Swan (Cygnus olor)

Denmark Barnacle Goose (Branta leucopsis)

Black-headed Gull (Chroicocephalus ridibundus)

Brant Goose (Branta bernicla)

Common Buzzard (Buteo buteo)

Common Eider (Somateria mollissima)

Common Pheasant (Phasianus colchicus)


Eurasian Sparrowhawk (Accipiter nisus)


Gadwall (Mareca strepera)



Mallard (Anas platyrhynchos)


Northern Gannet (Morus bassanus)

Northern Goshawk (Accipiter gentilis)

Peregrine Falcon (Falco peregrinus)


Taiga Bean Goose (Anser fabalis)

White-tailed Eagle (Haliaeetus albicilla)

Whooper Swan (Cygnus cygnus)

Finland Common Pheasant (Phasianus colchicus)

France Black-headed Gull (Chroicocephalus ridibundus)

Brant Goose (Branta bernicla)

38



Common Shelduck (Tadorna tadorna)




Red Knot (Calidris canutus)

Germany Accipitridae (unidentified) (Accipitridae (incognita))

Anatidae (unidentified) (Anatidae (incognita))

Anserinae (unidentified) (Anserinae (incognita))

Ardeidae (unidentified) (Ardeidae (incognita))

Charadriidae (unidentified) (Charadriidae (incognita))


Crane (unidentified) (Grus (incognita))

Gull (unidentified) (Larus (incognita))

Haematopodidae (unidentified) (Haematopodidae (incognita))

Laniidae (unidentified) (Laniidae (incognita))

Passeridae (unidentified) (Passeridae (incognita))

Rallidae (unidentified) (Rallidae (incognita))

Strigidae (unidentified) (Strigidae (incognita))

Swan (unidentified) (Cygnus (incognita))

Hungary Great Egret (Ardea alba)

Ireland Barnacle Goose (Branta leucopsis)






Italy Common Buzzard (Buteo buteo)

Eurasian Teal (Anas crecca)

Eurasian Wigeon (Mareca penelope)



Lithuania Mute Swan (Cygnus olor)

Netherlands Barnacle Goose (Branta leucopsis)



Eurasian Teal (Anas crecca)




Indian Peafowl (Pavo cristatus)


39


Muscovy Duck (Cairina moschata)


Phasianidae (unidentified) (Phasianidae (incognita))

Short-eared Owl (Asio flammeus)


Norway Barnacle Goose (Branta leucopsis)



Great Black-backed Gull (Larus marinus)

Mew Gull (Larus canus)



Poland Greylag Goose (Anser anser)




Romania Whooper Swan (Cygnus cygnus)

Russia Anatidae (unidentified) (Anatidae (incognita))

Common Pochard (Aythya ferina)



Tufted Duck (Aythya fuligula)

Slovakia Muscovy Duck (Cairina moschata)



Spain Greylag Goose (Anser anser)


Sweden Barnacle Goose (Branta leucopsis)

Eurasian Eagle-Owl (Bubo bubo)


40

Annex 4

UK wild bird detections by species indicting whether populations are largely

sedentary or migratory

Country & species H5N1 H5N5 H5N8 H5N3 H5Nx Grand Total Status

England 10 1 258 7 276

Black Swan 11 11 Sedentary

Brent Goose 6 6 Migrant

Buzzard 3 1 4 Sedentary

Canada Goose 1 24 25 Sedentary

Great White Egret 1 1 Sedentary

Grey Heron 1 1 Sedentary

Greylag goose 8 2 10 Sedentary

Herring Gull 2 2 Sedentary

Kestrel 1 1 Sedentary

Lesser Black Backed Gull 1

1 Sedentary

Lesser Black headed Gull 1

1 Sedentary

Mixed Avian 1 1 -

Mute Swan 8 1 155 1 165 Sedentary

Peregrine Falcon 2 2 Sedentary

Pink footed goose 2 2 Migratory

Shelduck 1

1

Partial migrant

but mainly

sedentary at this

time of year

Sparrow Hawk 1 1 Sedentary

Unspecified 1 1 -

Unspecified Goose 1 1 -

Unspecified Swan 11 11 -

Whooper Swan 21 2 23 Migratory

Wigeon 1

1

Migratory

Common Buzzard 1 2 3 Sedentary

Red Kite 1 1 Sedentary

Wales 5 1 6

41

Country & species H5N1 H5N5 H5N8 H5N3 H5Nx Grand Total Status

Little Grebe 1 1 Sedentary

Mute Swan 5

5 Sedentary

Scotland 17 2 19

Greylag goose 1 1 Migratory

Mute Swan 7 7 Sedentary

Unspecified Swan 4 4

Whooper Swan 4 4 Migratory

Knot 1 1 Migratory

Red Knot 1 1 2 Migratory

Northern Ireland 9

Peregrine Falcon 1 1 Sedentary

Unspecified Swan 6 6 -

Whooper Swan 2 2 Migratory

Grand Total 10 6 284 1 9 310

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