rapid risk assessment on incursion of hpai h5n8 into housed or … · 1 day ago · wild bird...

Rapid risk assessment on incursion of

HPAI H5N8 into housed or not housed

poultry flocks and captive birds

29 January 2021

Situation as at 26 January 2021

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Contents

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

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

Hazard Identification ......................................................................................................................... 10

Previous outbreaks of HPAI H5N8: ................................................................................................... 12

Current Situation ............................................................................................................................... 12

Risk Question .................................................................................................................................... 16

Risk Levels ..................................................................................................................................... 16

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

Exposure Assessment........................................................................................................................ 22

Domestic poultry ........................................................................................................................... 24

Captive birds ................................................................................................................................. 25

Ratites ........................................................................................................................................... 25

Game birds .................................................................................................................................... 26

Consequence assessment ................................................................................................................. 26

Conclusions ....................................................................................................................................... 28

Assumptions and Uncertainties ........................................................................................................ 30

References ........................................................................................................................................ 30

Annex 1 ............................................................................................................................................. 32

Annex 2 ............................................................................................................................................. 42

Annex 3 ............................................................................................................................................. 43

Annex 4 ............................................................................................................................................. 46

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Summary

This is an update of a rapid risk assessment undertaken on 26 November 2020 in

response to findings of HPAI H5N8 in poultry (on 02 November 2020) and wild birds

(09 November 2020). Since then, there have been further findings of HPAI H5N8 in

poultry, captive birds and wild birds in the UK, HPAI H5N1 in one backyard flock as

well as HPAI H5N1, H5N2 and H5N5 in wild birds. All updates made on 26 January

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

3 November 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. To 26 January, HPAI H5N8 has been detected at 12 poultry premises in

England with three outbreaks in captive birds; 1 poultry premises in Scotland; 2

poultry premises in Northern Ireland, with one outbreak of HPAI H5N1 confirmed in

poultry in England. To 26 January 2021 the last infected premises detected in GB

was in Devon, SW England, on 29 December 2020, while that in Northern Ireland in

County Antrim was detected on 11 January 2021. Wales reported an outbreak of

HPAI H5N8 on 27 January 2021 at a game rearing establishment.

4. There have been numerous reports of HPAI H5N8 in a range of wild bird

species, including migratory birds, resident birds and bridging species (including

gulls and a few corvids, namely Eurasian magpies) in Europe and UK. The arrival of

wild waterfowl to overwinter in the UK has by and large ended, and numbers are

expected to have peaked in December and January, depending on the species and

also the weather conditions in Continental Europe. Large populations of migratory

water fowl are still present in the UK. These birds will remain here till March/April and

will start departing in numbers from early/mid-March.

5. As of 26 January 2021 there were 299 wild bird positive findings of H5 in

England, Wales, and Scotland across 41 counties, and 25 different species. Of

there, 274 tested were subtyped as H5N8, 10 H5N1, 6 H5N5 and 9 H5Nx. 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.

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6. As a result of the ongoing infection pressure, the risk of AI H5N8 incursion in

wild birds is maintained at VERY HIGH.

7. There has been a pattern of spread consistent with previous disease epidemics

in which wild bird transmission was a primary factor. There is substantive evidence

that spread of H5 HPAI to GB by migrating wild waterfowl has happened on

numerous occasions since 2006.

8. Given the large poultry population and the proportion which are outdoor and in

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

exposure of poultry across the whole GB sill to be MEDIUM (where stringent

biosecurity is applied) and still to be HIGH (where biosecurity is sub-optimal). An

Avian Influenza Prevention Zone (AIPZ) is in place, and personnel should be taking

additional biosecurity measures.

9. Housing free range poultry could reduce the likelihood of infection incursion, by

reducing both the direct/indirect contact of free range poultry with wild waterfowl and

contact with the contamination in the environment. 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 equally or more effective (preventing wild bird contact and improving

biosecurity measures and education).

10. However, 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 affecting spread) or by other

items that are taken into or enter the housing. 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.

11. 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.

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Introduction

Across Northern Europe and 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. The OIE

Reference Laboratory at Weybridge has confirmed this strain is different to the HPAI

H5N8 virus circulating in East Europe earlier this year and different to the virus

circulating in 2016/2017.

Outbreaks and cases (wild birds) reported in the lead up to the first reports of HPAI

H5N8 in the UK on 09 November 2020 are shown in Table 1. 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.

Since then, there have been further findings of HPAI H5N8 in poultry, captive birds

and wild birds in the UK, HPAI H5N1 in one backyard flock as well as HPAI H5N1,

H5N2 and H5N5 in wild birds.

Table 1: Outbreaks and cases of HPAI H5N8 in Central Asia, Middle East and

Europe to early November 2020.

Date Country Details

August Central Russia, Kazakhstan Multiple poultry farms and wild bird

cases

September Russia (Caspian Sea);

Kazakhstan, Israel

Multiple poultry farms and wild bird

cases

10/10/2020 Russia (West near Belarus) Poultry – 28,000

16/10/2020 EU (Netherlands) Eurasian wigeon (live)

Two migration pathways contribute 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 not clear boundaries between these

migration routes and the birds will have mixed between them to some degree on the

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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 19 January

2021 are presented in Table 2.

Table 2: Current outbreaks of HPAI H5Nx in domestic poultry and captive birds

and cases in wild birds (from 19 to 26 January 2021), according to official

reporting sources. Note that this is a rapidly changing picture and new disease

reports are being made as we draft this risk assessment. (Annex 3 lists the wild bird

species involved in these reports).

Country

H5 H5N3 H5N5 H5N8

Total Wild/Captive

Birds

Wild/Captive

Birds Poultry

Wild/Captive

Birds Poultry

Wild/Captive

Birds

Belgium 1 1

Czech

Republic 1 1

Denmark 1 15 16

Finland 1 1

France 102 1 103

Germany 2 5 3 3 13

Ireland 1 3 4

Italy 1 1

Norway 3 3

Poland 2 1 3

Romania 2 2

Spain 1 1

Sweden 1 2 3

Ukraine 1 1

Total 3 3 1 6 108 32 153

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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 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 the epizootic of 2016/2017, many EU MSs put in place a

housing order. The orders may cover just certain sectors of commercial poultry and

certain high risk areas.

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.

The EU has recently warned that secondary spread between establishments keeping

anseriforme species is observed (PAFF, 2020, and communication from Cion).

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,

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

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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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 whether there

is evidence to help make decisions around mandatory housing. Any prevention order

would only be put in place in an area not already under restriction for a notifiable

avian disease.

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.

(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—

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(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 H5N8 HPAI subtype

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

H5N5.

Virus has been isolated from outbreaks and wild birds in the EU during the current

epizootic, and 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) has undertaken sequence analysis.

Diagnostic evaluation utilised frontline molecular assays and whole genome

sequencing techniques to define the genetic composition of the causative agent.

Importantly, despite various virus subtypes and genotypes, the haemagglutinin gene

is highly conserved (amongst these strains to date in the 2020/21 epidemic) and this

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factor critically underpins fundamental virus properties such as infectivity and

transmissibility.

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

viruses (reported by the lab 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 (and therefore distinct from the

strain that caused widespread outbreaks in the EU in the first part of this year).

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 cluster together whilst the H5N5 and H5N8 viruses appear to be more

closely related with H5N5 viruses sitting at different points within the main

Autumn/Winter 2020 cluster. All Autumn/Winter 2020 detected viruses cluster

together within clade 2.3.4.4B, but 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 2016-2017, 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.

On the other hand, the three H5N1 viruses are almost identical and 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 (6/8)

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, H5N2, H5N5, and H5N8. The detection of four 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 change by genetic reassortment in wild birds is not

unexpected, and further genetic variation at genome level may be expected as the

epidemic progresses.

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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

This year to date, there is a lack of evidence for whether some species of wild

waterfowl do not show clinical signs on infection with this virus strain and whether

the virus can continue to circulate 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).

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Map 1: Current outbreaks and wild bird cases of H5N8 HPAI (as of 26 January

2021).

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

Therefore, this new epizootic is following a similar pattern of transmission in wild

birds and spill-over into domestic poultry as 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, if not for many months, if the virus continues to circulate in migratory and then

in non-migratory waterfowl in Europe.

There are three emerging trends apparent in Continental Europe. The first trend of

note is that the rate of new wild bird case reports has fallen, and the total number of

wild bird cases has levelled off in December although may be slightly increasing

again in the last month. Thus, each European country only reported a handful of wild

birds cases in the week beginning 19 January 2021 (Table 2). To 26 January 2021,

this year there have been 93 wild bird cases of 844 in total since October; of which

38 were reported to OIE on 22 January. At this stage in the 2016/17 epizootic there

had been 625 wild bird cases, with cases rising to over 1,000 by mid-February 2017

in the second peak. There is, however, a suggestion of a second rise in wild bird

cases in early January this year; but it is too early to tell if this is a true second peak,

as was observed at the end of January 2017 in the 2016/17 H5N8 epizootic. ADNS

(data to 17/1/21) for EU MSs, plotted weekly by the EU Ref laboratory (IZSVe,

2021), show wild bird cases dropping off to very low numbers at the end of 2020

compared to the peak of ~150 per week in November 2020.

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However, the second week of January saw this jump to ~35 wild bird cases per week

falling to ~18 in the third week. Care needs to be taken in interpretation of wild bird

data in relation to the risk to poultry because surveillance activity may have reduced

in some countries over Christmas period. Wild bird cases and submissions appear to

be reducing in the UK, with associated lower infection pressure, but there will be a

lag effect with virus in the environment as the virus decays after wild bird

amplification. Although we have seen a definite reduction in the rate of new cases in

the UK, this cannot be solely attributed to the decrease in wild bird cases in

Continental Europe. The reduction in new cases in wild birds in the UK will ultimately

translate into lowering the infection pressure in the environment. The trends in wild

birds in both Europe and the UK are in a positive direction given normal infection

dynamics in wild birds.

The second trend in Europe is that overall the number of outbreaks reported in

poultry after appearing to increase slightly, particularly in Germany and Poland, is

now reducing. The exception is France, which has reported a large increase in

numbers as H5N8 spreads though the duck industry in the south-west (Table 2). The

situation in south-west France should not be used as an indicator for the UK

because it is not due to primary cases from wild birds, but due to secondary spread

in a challenging sector.

The third development is that outbreaks are now being reported in south-east

Europe, with Hungary, Slovakia and Romania now reporting HPAI. Until recently, this

epizootic has mainly been an outbreak of north-western Europe, although Italy and

Slovenia have been affected. This represents diffusion of the virus over a wider area

as local populations of wild birds become infected through localised movements.

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Risk Question

What is 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?

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

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 Joint Nature

Conservation Councils (JNCC), 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.

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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)

In terms of migration, the wild waterfowl will have been arriving in GB from Northern

Europe since August / September and numbers generally peak in December to

January. 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 will start again in March to May.

Expert opinion from the JNCC and BTO suggests that Eurasian wigeon, a species of

migratory duck, are most abundant in Netherlands and GB with some testing positive

for HPAI H5N8 in Germany, the Netherlands and the UK. Wigeon start arriving in the

UK from September with numbers building through October to December.

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Furthermore cases of live trapped or positive shot wild birds in Netherlands and Italy

suggests that “healthy” wild birds are carrying infection.

Figure 2. The combination of wild bird assemblages and poultry density as a

risk map, which informs the poultry survey, targeting the high risk areas.

See Annex 2 for estimated numbers of wild birds entering GB in comparison to the

Netherlands and Italy in any year (Flutest project 2014). It can be seen from these

data that for most migratory species, fewer birds arrive here than to the Netherlands

in any one year; nevertheless, there are still significant numbers. Although these

data are some years old, at present, we are seeing a usual seasonal flow of

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migratory birds, and this is not currently affected by any cold weather conditions in

Europe.

The frequency of peak occurrence of waterbird species by month and by county are

available on the Wetland Bird Survey website http://app.bto.org/webs-reporting/. For

example, the monthly frequency of the common teal and the Eurasian wigeon (the

two highest risk species according to Flutest) are shown here, based on the 2018/19

survey:

http://app.bto.org/webs-reporting/

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Given the daily reports of HPAI H5N8 in wild birds in Belgium, Denmark, Germany,

Ireland, Italy and Netherlands that were seen in October/November, the increasing

numbers of wild birds being found dead in Europe and the total populations involved,

and, more recently, the cases in Sweden, Norway, Romania, Hungary, Slovakia and

Slovenia, it is likely that there are still birds which are not showing clinical signs and

are able to migrate to the UK, although at this stage in late January this is less likely.

There is evidence that sedentary birds present in GB have been infected may still be

infectious with ongoing transmission and a source of virus circulation in other birds

within GB.

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 26 January 2021, there were 299 wild bird

positive findings of H5 in England, Wales, and Scotland across 41 counties, and 25

different species. 274 tested were subtyped as H5N8, 10 H5N1, 6 H5N5 and 9

H5Nx. 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, with mute

swans, greylag geese and Canada geese representing the majority of detections.

This is in contrast to 2016, when initial detections were found primarily in tufted

ducks, swans and gulls.

The Barnacle geese over-wintering in the Netherlands are different populations from

the GB populations, and probably come through the Baltic from Norway/western

Siberia, while the Barnacle geese that winter in Scotland either come from

Greenland (via Iceland) or from Svalbard (via north Norway). There, avian influenza

is rarely detected and represent a different migration flyway. In autumn, Greylag

geese mainly move south from Scandinavia, or in southern GB are resident bird

populations. Eurasian wigeon are migratory ducks from breeding areas in northern

Russia and Eastern Europe.

Although there is considerable uncertainty around the transmission of HPAI H5N8

from migratory to local sedentary species, HPAI H5N8-positive findings in GB are in

both migratory birds and resident birds (mallards, Canada geese, mute swans)

suggesting that significant local transmission of virus is occurring. These are detailed

in Annex 4.

A qualitative estimate of the numbers of migrating higher risk species of waterbirds

arriving in GB from various areas of Europe, Asia and Africa in autumn/winter is

shown in Table 3 by species (Gale et al. 2014).

21

However, the key message is that these birds have now arrived in the UK in these

numbers and we are now detecting both further spread within these populations

wintering within the UK and also increasingly spill-over event to our indigenous

sedentary populations as shown in Annex 4. Thus, the dynamic is shifting which

correlates to more sporadic wild bird cases which overall reduces infection pressure

in the environment and therefore reducing risk to poultry. In summary, the

indigenous birds provide an ongoing background risk after multiple primary

introductions via migratory waterfowl.

Table 3. Qualitative estimation of number of higher risk species of waterbirds

migrating from different regions of the world to GB, the Netherlands and Italy

(per year) (n). This is based on numbers of birds in Annex 2. Negligible numbers

are excluded (Gale et al. 2014)

Species Western

Europe

Eastern

Europe

Asia West

Africa

East and

Southern

Africa

Bewick’s swan L L VL

Whooper swan L VL VL

Mute swan M VL

Greater white-fronted goose VL VL VL

Greylag goose VL

Red-breasted goose VL

Eurasian wigeon H M M L

Common teal H L L L

Mallard M L L VL

Northern pintail M L L L VL

Garganey VL VL VL VL VL

Northern shoveler L VL L VL

Common pochard L L L VL

Tufted duck M L L

Black-headed gull H L L

Number of individual birds in each qualitative category: >1,000,000 Very high (VH); 100,001 -

1,000,000 High (H); 10,001 – 100,000 Medium (M); 1,001 – 10,000 Low (L); 1 - 1,000 Very Low

(VL); 0 Negligible (excluded)

Based on the numbers of wild bird cases in north-western Europe to date this

season compared to the 2016/17 outbreak, it is concluded that the wild bird infection

pressure is higher and there is evidence that sedentary wild bird species in the UK

are now infected (see Annex 4).

22

Bridging species include several sedentary indigenous birds, such as gulls and

corvids. Many gulls but also a few corvids (namely Eurasian magpies), have tested

positive for HPAI H5N8 on the Continent and in the UK. As bridging species, gulls

are known to have long daily flight patterns between feeding sites, such as open

farmland or rubbish tips, and their night roosts such as reservoirs and gravel pits.

They are likely to have a role in fomite transmission from areas where there is

environmental contamination. Fomite transmission via multiple pathways is

particularly important in the current situation, considering the environment is high risk

across the country.

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

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

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

waterfowl. LOW 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.

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

23

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

these measures mean.

Contact with live infected wild birds, particularly waterfowl:

Wild birds will forage for food away from their assemblages and geese in particular

may move up to 7km on a daily basis. As more migratory birds arrive and if the

weather worsens over winter, they may also move away from the coast and be

observed inland. In addition, gulls which can act as a bridging species, fly tens of km

a day to feed, returning in the evening to their over-night sites.

Housing birds will reduce direct contact with wild waterfowl. 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 in the near environment

and how attractive the site is to such 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.

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

temperatures, at least to 55 days at 4oC (Ian Brown, APHA, Pers. Comm.). This

means the environment could remain contaminated for several weeks or more.

Preliminary APHA data indicate that the current H5N8 HPAI virus could have

extended survival properties, compared to the 2016 H5N8 virus, but further work is

ongoing.

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.

Although in the 2016/2017 season, the (few) 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.

24

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

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.

25

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

populations according to the 2018 poultry register:

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

Note: 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.

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.

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

26

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 are 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 still to be MEDIUM (where stringent

biosecurity is applied) to HIGH (where there are biosecurity breaches) (LOW

uncertainty). Twenty infected premises have been identified across England,

Scotland, Northern Ireland and, most recently, an infected premises with game birds

in Wales. Furthermore, HPAI H5N8 (and other subtype combinations) has been

confirmed in many wild birds in England, Scotland, Wales and Northern Ireland.

However, it is important to emphasise both the role of wild ducks and geese visiting

poultry premises, and the bridging species flying over or visiting sites. 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.

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

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

27

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.

The area of any prevention order which included housing could be done under a

Ministerial Order, at a national, regional or county level or at a smaller area level. In

terms of delineating these areas, the interactive map available at

https://defra.maps.arcgis.com/apps/webappviewer/index.html?id=8cb1883eda5547c

6b91b5d5e6aeba90d uses the risk-based poultry survey model, which already takes

into account the areas of high wild waterfowl populations (Figure 1) and a “foraging

distance” for waterfowl. Consideration should also be paid to the different poultry

populations which could be housed without compromising welfare. A national order

or even a regional order would be of significant consequence to the poultry sector

where the risk reduction is not considered to be significant. That consequence is

around the possible increase in risk of the other pathways which could bring avian

disease into contact with the poultry, through increasing the level of contact with

workers and increasing transmissibility of viruses between the birds when they are in

close contact with one another. This could also increase the risk of mutation of LPAI

viruses into HPAI viruses as seen with previous outbreaks in Europe for H7 viruses.

https://defra.maps.arcgis.com/apps/webappviewer/index.html?id=8cb1883eda5547c6b91b5d5e6aeba90dhttps://defra.maps.arcgis.com/apps/webappviewer/index.html?id=8cb1883eda5547c6b91b5d5e6aeba90d

28

Options for the area of any prevention order are therefore considered as

follows:

Sector National Regional County level Small 10/10

km2 zones

Chickens Not

considered

appropriate

based on the

variable risk

level for any

species

Not

considered

appropriate

based on the

variable risk

level for any

species

Possible and easiest

to mandate but not all

premises at same risk

level

Preferred but

difficult to

operate

Turkeys

Ducks

Geese Not considered

appropriate for these

species

Not considered

appropriate for

these species

Gamebirds

Ratites

Captive birds Recommendation around separation of

birds and preventing wild waterfowl

access

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, there have been twelve outbreaks of HPAI H5N8 in poultry confirmed on

premises in England, and one outbreak confirmed on a premises in Scotland. There

have also been three cases of HPAI H5N8 in captive birds in England, and one case

of H5N1 in backyard chickens, in England. In addition, there have been two

outbreaks in poultry confirmed in Northern Ireland. On 27 January H5N8 was

confirmed at a game rearing establishment near Amlwch, Isle of Anglesey, Wales.

Housing should only be applicable to those species where the welfare of the birds is

not compromised.

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.

At this stage at the end of January few migrating waterfowl are expected to enter the

UK from Europe even if the weather were to deteriorate significantly in the coming

weeks. Even if a few more birds did fly over, this would not necessarily increase the

estimated risk areas alluded to in this document, given the VERY HIGH level already

29

assessed for wild birds. The migration season for wild waterfowl to overwinter in the

UK has by and large ended, and numbers are expected to have peaked in

December and January, depending on the species and the weather conditions in

Continental Europe. A large population of migratory water fowl are still present,

however, and will not be leaving the UK until March/April. Furthermore, there is

evidence of spread to sedentary birds in the UK.

If the HPAI H5N8 virus circulates in native sedentary wild waterfowl and becomes

established, as happened with HPAI H5N1 in 2005-2008, then housing could not be

applied for such a long period. In the current demographic, sedentary species are

now largely those testing positive. The survival of the virus in the environment during

winter means the risk will not decrease for a period of weeks at the earliest. The

higher survival rate of the 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. Higher

environmental temperatures, together with increasing sunlight intensities will reduce

environmental levels of H5N8 and the associated risks.

As discussed above, a second peak occurred at this time of year in the 2016/17

H5N8 epizootic. Monitoring weekly changes over the next few weeks is therefore

important with regard to trends (up or down) in infection risk based upon number of

poultry incursions and level of detections in wild birds both in the UK and on the

continent.

If the risk has not changed and no new outbreaks or cases have been detected in

GB, despite passive surveillance and testing of wild birds found dead, the prevention

order should be reviewed after the peak migratory wild waterfowl occurrence is past,

i.e. at end of January. However, an outbreak of HPAI H5N8 was confirmed in GB on

28 January 2021.

The following conditions could 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 if time has lapsed since the last reported case and 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. These could form part of the “exit strategy”

although other factors including the uncertainties listed below need to be considered.

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

30

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

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.

• The patterns of movement of gulls are more complex than waterfowl. They prefer to

roost around land tips and reservoirs, therefore these should not be ignored as

potential sites of concern for proximity to poultry farms.

• 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) J.efsa.2017.4991

EFSA (2017a) So.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.

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

31

PAFF (2020) 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.pdfhttps://ec.europa.eu/food/sites/food/files/animals/docs/reg-com_ahw_20201020_pres_hpai_efsa.pdf

32

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

33

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

34

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

35

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 Eurpe the Middle East and North Africa.

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

36

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

37


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

38


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

39


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

40


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

41


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.

42

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

43

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)

Pink-footed Goose (Anser brachyrhynchus)

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)


44

Country Wild bird species affected

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)




Peregrine Falcon (Falco peregrinus)

Whooper Swan (Cygnus cygnus)

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)

Eurasian Wigeon (Mareca penelope)


Greylag Goose (Anser anse

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