Overview

Purpose and scope

This guidance supports the public health management of avian influenza (AI) and other zoonotic influenza (ZI) in Scotland.

The guidance is structured as a guide to applying a range of UKHSA guidance on AI and ZI in Scotland. This approach has been chosen to allow rapid updates to the guidance for this evolving threat. It signposts and adapts the UKHSA guidance for application in the Scottish context.

It is designed to support the development of local arrangements and assist in response, while maintaining a reasonable expectation that agreed health protection principles and national policy are supported and implemented to good effect in line with the Public Health etc. (Scotland) Act 2008.

This includes exercising functions in a manner that encourages equal opportunities and in observance of equal opportunities requirements.

This guidance does not replace individual expert clinical judgment or local response arrangements.

Employers should be advised to consider the specific conditions of each individual place of work and comply with all applicable legislation, including the Health and Safety at Work etc. Act 1974.

Out of scope

The guidance does not cover the clinical management of avian influenza.

Intended audience

This guidance is for use by health protection teams (HPTs) and other professionals involved in the public health management of avian influenza or zoonotic influenza.

How to use this guidance

This guidance is to be used to interpret and apply the current UKHSA guidance for the public health management of AI/ZI in the Scottish context.

Management should be broadly consistent across the UK, however, UKHSA guidance has been written with users in England as the target audience and is not always directly applicable in Scotland.

This guidance aims to provide a guide to where principles are the same, and to provide support for any interpretation required.

UKHSA guidance and resources

Summaries of the key UKHSA guidance resources.

  • Covers H5 AI/ZI only.
  • Provides case definitions of infected birds and other animals.
  • Classifies the human exposure risk into high and low risk categories and recommends health protection measures for these exposure categories.
  • Provides advice on personal protective equipment (PPE), diagnostic testing and antiviral prophylaxis.

View the guidance for the management of people exposed to birds or other animals infected with influenza A(H5).

  • Covers AI/ZI of all subtypes (not just H5).
  • Provides guidance on assessing and managing human health risks during AI incidents.
  • Outlines roles of various agencies in managing AI/ZI incidents, including:
    • Department for Environment, Food and Rural Affairs (Defra),
    • Animal and Plant Health Agency (APHA)
    • UKHSA
  • Describes procedures for alerting and managing AI incidents and emphasizing collaboration among local authorities, the NHS, and other stakeholders.
  • Provides algorithms for assessing and managing individuals exposed to AI, including guidance on PPE usage and post-exposure prophylaxis.

View the guidance for the management of the human health risk of avian influenza of poultry and wild birds.

  • Provides case definition for possible human cases.
  • Recommends public health actions for HPTs for isolation, hospital transfers, and clinical assessment for public health management.
  • Includes information regarding notification of positive results.

View the guidance for the investigation and management of possible human cases of avian influenza amongst contacts associated with avian influenza incidents.

  • Provides case definition for possible cases.
  • Details information on notification of results of testing.
  • Gives recommendations for the management of contacts of presumptive positive or confirmed human cases of avian influenza who were exposed when the case was symptomatic or 1 day before symptom onset.

View the guidance for the investigation and initial clinical management of possible human cases of avian influenza with potential to cause severe human disease.

  • Gives information according to a decision tree to determine if testing is necessary.
  • Provides guidance on obtaining samples for testing and their transfer to the public health laboratory.
  • Details how notifications and reporting of positive and negative results must be made.

View the protocols for laboratory investigations for suspected avian Influenza A(H7) and A(H5) human infections.

For the full UKHSA collection, go to the UKHSA avian influenza: guidance, data and analysis.

Responsible organisations

Organisational roles and responsibilities for AI/ZI are set out in the guidelines on the roles and responsibilities of agencies involved in the investigation and management of zoonotic disease in Scotland.

The UKHSA guidance refers to some organisational roles and responsibilities which are different for Scotland.

What applies in Scotland

The following organisational roles and responsibilities apply in Scotland. 

Scottish Government Animal Health and Welfare plays a central role in AI/ZI incident management.

They provide strategic oversight, policy enforcement, and public communication.

They work in close partnership with APHA Scotland, local authorities, and the poultry industry to control AI outbreaks, protect animal health, and minimize the impact on Scotland’s poultry sector. 

Find out more about Scottish Government Animal Health and Welfare.

APHA Field Services Scotland undertake regular surveillance and monitoring of wild birds and commercial or backyard flocks.

They carry out on-site investigations at affected premises and implementation of control measures in birds and animal populations.

Find our more about APHA Field Services.

NHS health protection teams (HPTs) undertake the roles and responsibilities of local and regional UKHSA health protection teams.

They are responsible for leading the public health management of avian influenza in their board area.

Contact a health protection team.

Public Health Scotland undertake the national role of UKHSA.

We do this in partnership with Antimicrobial Resistance and Healthcare Associated Infection (ARHAI) Scotland, Scottish Government and other national agencies.

Find out more about PHS.

Edinburgh Specialist Virology Centre and West of Scotland Specialist Virology Centre provide specialist advice and laboratory testing (including subtyping) in Scotland.

UKHSA reference laboratories in Colindale provide further typing support.

Refer to point 3 (testing) in the avian influenza incidents section on testing in Scotland for more information. 

Find out more about the Edinburgh Specialist Virology Centre and West of Scotland Specialist Virology Centre.

Background

What is avian influenza?

Throughout this guide, where not referring to a particular subtype, the term HxNx is used.

Avian influenza is an infectious disease of birds caused by the influenza A virus.

Birds are the hosts for most avian influenza viruses and a variety of influenza subtypes can be found in birds, particularly in waterfowl and shore birds.

Domestic poultry are especially vulnerable, and the virus can rapidly cause epidemics in flocks.

The AI viruses are categorized into subtypes based on two surface proteins:

  • hemagglutinin (HA)
  • neuraminidase (NA)

HA protein enables the virus to bind to and enter host cells and the NA enzyme facilitates the release of new virus particles from infected cells, allowing the infection to spread.

There are 18 known HA subtypes and 11 known NA subtypes, leading to various combinations such as H5N1 or H7N9. ​The specific combination of HA and NA proteins determines the virus subtype, influencing its properties, including host range, transmissibility, and pathogenicity.

Avian influenza (AI) viruses principally affect birds, but some may be associated with infection in mammals, including humans. These are known as zoonotic influenzas (ZI).

Highly pathogenic avian influenza (HPAI)

Avian influenza viruses are classed as highly pathogenic avian influenza (HPAI) or low pathogenicity avian influenza (LPAI) according to their ability to cause severe disease and death in chickens. 

This classification does not relate to pathogenicity in humans – zoonotic infections in people have been reported from both HPAI and LPAI.

HPAI is primarily associated with specific subtypes of the influenza A virus that have caused significant outbreaks in bird populations and, in some cases, have infected humans.

Notable HPAI subtypes

H5 Subtypes
    • H5N1: First identified in 1996, H5N1 has led to severe outbreaks in poultry and has infected humans, resulting in high mortality rates. ​
    • H5N6: Emerging in recent years, H5N6 has caused infections in both birds and humans, particularly in Asia. ​
    • H5N8: Detected in multiple continents, H5N8 has primarily affected bird populations but has also been reported in mammals. ​
    • H5N5: This subtype has been identified in wild birds and poses a risk to poultry. ​
    • H5N9: Recently detected in the United States, H5N9 has raised concerns due to its potential to infect humans.
H7 Subtypes
    • H7N9: First reported in China in 2013, H7N9 has caused human infections with a high case-fatality rate. ​
    • H7N7: Known to infect both birds and humans, H7N7 has been associated with outbreaks in poultry and occasional human cases. ​
    • H7N8: Recently detected in Australia, H7N8 has led to outbreaks in poultry farms.

High consequence infectious disease

Certain subtypes of AI are considered as high consequence infectious disease (HCID).

HCIDs are acute infectious diseases that typically have:

  • a high case fatality rate
  • limited treatment
  • limited preventative options

Airborne HCIDs are those that are spread by respiratory droplets or aerosol transmission, in addition to contact routes of transmission.

All HCIDs require a heightened level of response for patient care, infection prevention and control, and public health management.

See the guidance section on HCID management for more details. 

Some subtypes of AI (H7N9, H5N1, H5N6 and H7N7) in the UK are classed as airborne high consequence infectious diseases (HCIDs).

Current epidemiology

H5N1 outbreak

From 2021, a particular HPAI of subtype H5N1 has caused a global outbreak affecting many bird species. This has resulted in unprecedented losses in wild and farmed bird populations and, on occasion, spill-over to mammals.

Importantly, this H5N1 is of clade 2.3.4.4b, which is different to the H5N1 clade (2.1.2.1c) that continues to circulate in the Far East.

Infections in mammals

As of April 2025, H5 subtypes (mainly H5N1 but also H5N5) have been detected from at least 70 species of mammal across almost every continent. Most of these mammals are thought to have predated on infected bird carcasses without mammal-to-mammal transmission.

Guidance for H5 subtypes is informed by an annual risk assessment of the H5 subtype circulating in Europe. Other risk assessments, such as by the Human Animal Infections and Risk Surveillance (HAIRS) group, are also used to inform the risks of avian influenza from exposure from mammalian sources.

Infections in dairy cows

Since May 2024 there has been an outbreak of H5N1 2.3.4.4b in dairy cows on dairy farms across the USA. This is predominantly of a particular genotype – B3.13 – though some recent bovine cases have been associated with genotype D1.1, neither of which have yet been observed in the UK.

Whilst the source of infection is from birds, transmission between cows appears to be predominantly mechanical – from udder-to-udder via the milking process – while between-farm transmission is suggested to occur via the movement of animals, vehicles and other fomites.

Infections in humans

Avian influenza

There have been a number of human cases of varying severity across the globe from a variety of AIs including from H5 subtypes (H5N1, H5N2, H5N6, H5N8), H7, H9 and H10 subtypes (H7N3, H7N9, H9N2, H10N3) as well as cases previously reported from other subtypes (H3N8).

Zoonotic influenza

ZI variants of swine origin (H1N1v, H1N2v) are sporadically identified in humans. Most human cases associated with the H5N1 clade 2.3.4.4b (circulating in the UK and currently in the USA) have been mild, with no evidence of person-to-person transmission.

Epidemiology updates

For the latest updates on avian or zoonotic influenza epidemiology, consult these resources:

Notification

In humans

Influenza virus of all types, including those caused by a new sub-type, is a notifiable infection under the Public Health etc. (Scotland) Act 2008.

Read guidance for clinicians on when to suspect influenza A(H5) in patients who are symptomatic and who have been exposed.

If the patient is considered to meet the clinical case definition, the clinician or microbiologist should follow the 'laboratory investigations for suspected avian influenza A(H5) and A(H7) human infections in Scotland flowchart'.

HPTs should immediately notify PHS of all possible cases and test results, when available:

In animals

For the purposes of the Public Health etc. (Scotland) Act 2008, laboratory directors should consider all avian or zoonotic influenza as an urgent notification.

In Scotland, APHA are required to inform the HPT concerned at various points in the investigation process for avian influenza on a premises:

  • at the point of suspicion of disease in a flock
  • at the point of samples being collected
  • on receipt of the test result

This early communication by APHA Scotland to the relevant HPT is deemed very valuable.

It allows HPTs to advise a suspected IP, in advance of a positive result, of what to expect regarding public health follow-up and possible next steps.

Public health management of avian influenza incidents

When HPAI affects a bird flock in Scotland, to contain the spread it is government policy – through the Avian Influenza and Influenza of Avian Origin in Mammals (Scotland) Order 2006 – to cull all poultry on that premises.

This is known as an avian influenza incident (AI incident).

The public health management role during an AI incident includes:

  1. identification and assessment of exposed people
  2. follow-up of exposed people
  3. testing
  4. isolation, treatment of cases and contact tracing
  5. communication
  6. incident management

The public health actions are detailed in UKHSA guidance on the investigation and management of possible human cases of avian influenza amongst contacts associated with avian influenza incidents

Scotland specific processes to be followed for public health management of AI incidents are explained in the investigation and clinical management flowchart.

1. Identification and assessment of exposed people

Following the identification of an AI incident, initial risk assessment to identify all individuals who may have been exposed and assess the nature of the exposure is required.

Risk assessment

Details of the information required as part of the risk assessment are shown in table 2 of UKHSA management of the human health risk of avian influenza of poultry and wild birds: guidance for health protection teams.

Risk assessment is based on:

  • the confirmed or suspected HxNx strain of AI/ZI
  • the level of exposure
  • type of contact
  • presence of symptoms
  • any use of personal protective equipment

Exposed people can include:

  • farmers, farmworkers or smallholders on premises with an AI incident
  • those coming into contact with infected wild birds, including those contracted to collect samples from deceased wild birds as part of avian influenza surveillance
  • those exposed to infected wild or domestic mammals, including those who collect dead wild birds or mammals on behalf of APHA for surveillance purposes and are likely to be wearing PPE
  • APHA staff or subcontractors attending an IP as part of investigation, culling and disinfection processes, who are likely to be wearing PPE

Of note, people employed by APHA directly or as sub-contractors working on infected premises with H5 (but not collecting wild birds) will be monitored by APHA for use of PPE and passive follow up.

The quality of PPE available to staff from the poultry culling and cleaning & disinfection (C&D) companies can vary, as can adherence to the PPE required. Be aware that there may have been breaches even when a person states that PPE has been worn.  

Appropriate PPE for persons collecting wild birds as part of a surveillance programme are advised to wear full PPE but will need to be contacted by the HPT to assess risk and potential breaches of PPE.

For wild bird carcass collection, the suite of recommended PPE should be worn.

Personal protective equipment

For working with suspected or confirmed infected poultry, the appropriate PPE is set out by the Health and Safety Executive (HSE) and consists of:

  • disposable or polycotton coverall with head coverage of CE type 5 and 6 that offer protection against dusts, splashes, and liquid sprays (with, as appropriate, safe disposal or cleaning after use)
  • disposable gloves of lightweight nitrile or vinyl or heavy-duty rubber (not latex) gloves that can be disinfected
  • rubber or polyurethane boots that can be cleaned and disinfected
  • FFP3 respirator with exhalation valve
  • close fitting goggles or other equipment that gives at least the same level of protection

2. Follow-up of exposed people

Approach

For any exposed person there is a 10-day follow up period.

There are two approaches:

  • standard approach – 10-day passive follow up
  • strict approach – active follow up daily for 10 days and offer of antivirals

For certain scenarios (for example, in cases of a lower risk level of exposure), a standard approach may be deemed by the HPT to be more appropriate than a strict approach (see note 1 in the human zoonotic influenza incident management tool).

HPTs may find it helpful to make early contact with owners of suspected infected premises so that they are prepared for the follow up process should the premises test positive.

Protocol

APHA have a protocol for sending a line list of contracted and sub-contracted staff attending premises to HPTs. They will also have occupational health provision for follow-up of staff wearing full PPE without a breach.

Wild birds that are detected as infected with avian influenza are typically those tested as part of a surveillance scheme for the detection of avian influenza in wild bird populations.

On the receipt of a positive result in a wild bird, APHA will send the HPT details of the person(s) collecting and submitting the carcass or samples for testing.

Individuals contracted to collect samples or carcasses on behalf of APHA would be expected to be wearing full PPE. However, depending on the circumstance, this may not always happen.

Therefore, HPTs are advised to ascertain whether those involved in collection of the carcass or samples were wearing full PPE.

  • Those that were wearing full PPE are considered low risk and receive passive follow-up for 10 days.
  • Those that were not wearing full PPE or suffered a breach are considered high risk and require active follow up for 10-days and the offer of antivirals.

Prioritisation

Because commercial flocks are tested as a priority over wild bird surveillance, capacity for testing may mean that there may be occasions when a wild bird notification is received after the 10 day follow up period.

Health protections teams are not required to follow up individuals after the 10 day period, although a risk assessment and a call to those falling just outwith this period to perform a wellness check, and communicate messages around PPE, is helpful, particularly when there is member of the public involved.

Antiviral treatment outside this 10-day post exposure period is unlikely to be necessary.

Exposed individuals

The APHA vets and farm staff are usually the initial exposed individuals on a premises.

Subsequent processes usually involve teams of poultry culling and cleansing and disinfection (C&D) staff from poultry worker companies subcontracted by APHA.

  • Culling and C&D staff are often itinerant workers, with language barriers.
  • They are often working sequentially at premises across large geographical areas, very often across the UK.
  • When there are a number of outbreaks across Scotland, there can be challenges in follow-up of these individuals.
  • Automatic messaging in HPZone could be useful.
  • An email follow-up system as opposed to daily phone calls is recommended.

On occasion, culling and C&D staff sometimes self-present at A&E. HPTs are advised to work with the employing agencies of these staff to guide them to liaise with the local HPT for arrangements regarding appropriate triage and treatment rather than presenting directly.

3. Testing

HPTs should immediately notify PHS of all possible case and test results, when available, by:

Individuals that are identified as requiring diagnostic testing (based on clinical symptoms and/or exposure history) should have samples collected and tested at the appropriate lab.

In Scotland, samples must be sent to one of the following two labs:  

  • Specialist Virology Centre (SVC), Edinburgh Royal Infirmary
  • West of Scotland Specialist Virology Centre (WoSSVC), Glasgow Royal Infirmary.

Both SVC and WoSSVC can perform influenza A testing (including H5 or H7 subtyping).  

Additionally, sequencing can be performed at WoSSVC. If sequencing cannot be performed by WoSSVC (for example, due to assay failure), samples will be sent to the Respiratory Virus Unit (RVU) at Colindale.

Follow the laboratory Investigations for suspected Avian Influenza A(H5) and A(H7) Human Infections in Scotland flowchart for more information on testing.

Testing in remote and rural areas

NHS boards covering remote locations, particularly islands, where transportation of swabs is likely to take longer, may wish to prepare alternative protocols for local interim testing for flu A while waiting for results from SVC or WoSSVC.

This approach allows provisional results to be used as part of a wider risk assessment for patient management.

Such protocols should bear in mind that local assays (including those validated for H subtypes) are likely to be of lower sensitivity than those from SVC or WoSSVC.

As such, confirmatory testing should always be performed by SVC or WoSSVC labs before standing down any public health action, including isolation and contact tracing.

Any local testing should be performed at appropriate containment level as per advice from the Advisory Committee on Dangerous Pathogens (ACDP):

  • CL3 for samples collected in viral transport medium (VTM)
  • CL2 following local risk assessment for samples collected in molecular sampling solution (MSS)

4. Isolation and treatment of cases, and contact tracing

Exposed individual who are asymptomatic or show no symptoms

Individuals exposed to a confirmed AI incident in birds in the UK are not required to be tested or self-isolate unless they experience symptoms. In the case of asymptomatic individuals undergoing testing (for example those who are swabbed as part of UKHSA’s enhanced surveillance programme of workers on IPs, currently carried out in England only), isolation is not necessary prior to laboratory results being available. 

Exposed individual who are symptomatic

An individual exposed to a confirmed AI incident in birds in the UK who becomes unwell should be tested, asked to self-isolate until results are available and, where clinical symptoms warrant, hospitalised (with appropriate isolation of patient and PPE for, staff and patient).

HCID management

High Consequence Infectious Disease (HCID) management is required for those with appropriate travel and/or exposure history or case confirmation with certain subtypes (e.g. H5N1, H5N6, H7N7, H7N9).

Close contacts

Close contacts of presumptive or confirmed positive human cases should be offered chemoprophylaxis and undergo active follow-up for 10 days after last exposure.

Antiviral chemoprophylaxis should be offered to these individuals as soon as possible (ideally within 48 hours) with an oseltamivir treatment dose course (75mg twice daily for 5 days).

Antiviral post-exposure prophylaxis, follow-up or self-isolation of contacts of exposed individuals is not normally initiated until the receipt of presumptive positive or confirmed laboratory results for the case, in accordance with UKHSA guidance.

Confirmed positive cases

On confirmation of a positive laboratory result, all HxNx (excludes circulating human influenza strains such as pmd09 H1N1 etc) cases should be isolated and treatment with antivirals started immediately.

Contact tracing and testing of contacts should also ensue without delay.

The case should be managed as appropriate according to the risk associated with the HxNx subtype, in discussion with the duty infectious disease consultant.

In the case of individuals with suspected AI of a subtype and clade known to cause severe disease in humans (this would include returning travellers in close contact with poultry in live bird markets, exposure in a laboratory setting, exposure to a UK mammal with ZI, or from a confirmed AI incident in birds in the UK, contingent on risk assessment) the guidance for the investigation and management of possible human cases of avian influenza with potential to cause severe human disease should be followed (see the laboratory investigation pathway for suspected human infections).

5. Communications

Public communications as necessary (regionally, or nationally following prior discussion with PHS).

For more information refer to the management of public health incidents: guidance on the roles and responsibilities of NHS led incident management teams.​

6. Incident management

A local IMT should be established to manage any presumptive or confirmed cases.

A confirmed case may constitute an incident requiring a national response due to the potential public health impact occurring across regional boundaries and the need for national co-ordination.

For more information refer to the management of public health incidents: guidance on the roles and responsibilities of NHS led incident management teams.​

Public health management of sporadically exposed individuals

APHA carries out year-round avian influenza surveillance of dead wild birds submitted through public reports and warden patrols.

The purpose of the surveillance and testing of wild birds is to capture information on the location and strains of avian influenza that might be prevalent in Great Britain. This data then helps government to build up a picture of the current risks and shapes the response to this risk.

Scottish Government provides guidance for the general public on what to do if a dead bird or animal is found.

Public health management of imported cases

Other than domestic exposure, people may become infected with AI when travelling abroad. This may involve strains not recently circulating in the UK or Europe.

The public health management of human cases and contacts includes the:

  • management of clinical cases (which may be mild to severe, depending on the subtype and clade concerned as well as patient factors)
  • prevention of spread to other people

For more information on the management of imported cases and their travel contacts, refer to the UKHSA guidance on investigation and initial clinical management of possible human cases of avian influenza with potential to cause severe human disease.

HCID pathways

General principles

Some subtypes of AI (H7N9, H5N1, H5N6 and H7N7) in the UK are classed as airborne high consequence infectious diseases (HCIDs).

In Scotland, in situations in which a case is to be managed as an HCID, general principles for the management of HCIDs should be followed.

These include:

  1. informing HPTs early on of a possible case
  2. managing the possible case in such a way as to prevent transmission to people and birds or animals while tests are being conducted.
  3. contact tracing and communication as necessary to prevent onward transmission.
  4. following the IPC guidance in the NIPCM guidance for avian influenza

Use of PPE

ARHAI Scotland published the HCID addendum in April 2025 which contains guidance on the use of the new UK HCID assessment PPE ensemble required to be worn by healthcare workers caring for a suspected or confirmed HCID regardless of the transmission route.

NHS boards in Scotland have until April 2026 to implement the new ensemble and once transition is complete, healthcare workers should follow the guidance within the HCID addendum for PPE.

Until the transition is complete, historical PPE guidance within the NIPCM guidance for avian influenza will remain available for use.

Next steps

Potential steps, underpinned by risk assessment, would likely include:

  • an initial request for the patient to self-isolate
  • notification of the possible case to an infectious diseases physician who discusses with the Imported Fevers Service and conducts a risk assessment
  • discussion of the risk assessment result is with the Consultant Public Health or Consultant Public Health Medicine (CPH/CPHM) and a decision made on whether the patient needs to be admitted
  • alerting the Scottish Ambulance Service early on in the process
  • notification of the patient to the receiving heath board should be made in advance of a patient being moved
  • the formation of a problem assessment group (PAG) as soon as possible to ascertain:
    • key people
    • risk assessment of the situation
    • options for patient
    • sample transport and plans for coordination
    • clinical care
    • contact tracing
    • communications
  • consideration of the likely impact of actions on other services, which should be taken into account in making final decisions to minimise harm

Additional resources

Human zoonotic influenza incident management tool

This decision tool is for the management of possible cases of avian influenza in persons exposed to confirmed detections of avian influenza in avian species.

Refer to the UKHSA investigation and initial clinical management of possible human cases of avian influenza with potential to cause severe human disease for:

  • cases not associated with exposure to avian incidents
  • severe human cases of any origin

Download the print version of the management tool

Accessible text versions

  • Start: Animal and Plant Health Agency (APHA)/ Scottish Government Animal Health and Welfare (SGAHW) notified of suspected case of zoonotic influenza in an animal.
    • Action: Proceed to Step 1.
  • Step 1: Restrictions imposed on site.
    • Action: Proceed to Step 2.
  • Step 2: APHA vet officer conducts clinical investigation.
    • Decision: Is zoonotic influenza (ZI) ruled out?
      • Option A: ZI ruled out through clinical investigation.
        • Action: Restrictions are lifted.
        • End: Process complete.
      • Option B: ZI not ruled out through clinical investigation.
        • Action: Samples are sent to Weybridge for testing.
        • Action: Proceed to Step 3.
  • Step 3: Laboratory testing at Weybridge.
    • Decision: Are lab results negative or positive?
      • Option A: Negative lab results.
        • Action: Restrictions are lifted.
        • End: Process complete.
      • Option B: Positive lab results.
        • Action: Proceed to Step 4.
  • Step 4: Positive lab results confirmed.
    • Action 4a: SGAHW declare infected premises.
    • Action 4b: Cull of infected population is considered/initiated.
    • Action 4c: Subtype confirmed.
    • Action 4d: Proceed to step 5.
  • Step 5: Public health actions from local health protection team triggered.
    • Action: Proceed to flowchart 2.
  • Start: Health Protection Teams (HPTs) conduct initial risk assessment to identify exposure risk.
    • Action: Refer to page 12 of relevant guidance.
    • Action: Consider Incident Management Team (IMT) for large outbreaks or novel high-risk situations.
    • Decision: Is exposure risk low or high?
      • Option A: Low exposure risk.
        • Action: Follow standard approach [see note 1]. Passive follow-up of potentially exposed individuals (no antivirals prescribed).
        • Action: Proceed to Step 1.
      • Option B: High exposure risk.
        • Action: Follow strict approach [see note 2]. Active follow-up of potentially exposed individuals (prescribe antivirals).
      • Specific follow-up for APHA staff.
        • Action: Passive follow-up for APHA staff who attended the incident.
        • Action: Proceed to Step 1.
  • Step 1: Testing after risk assessment.
    • Action: Test symptomatic exposed individuals.
    • Action: Refer to the Zoonotic Influenza (ZI) testing pathway for Scotland.
    • Decision: Are lab test results negative or positive?
      • Option A: ZI ruled out by negative lab test.
        • Action: Process ends.
        • End: No further action required.
      • Option B: Human ZI confirmed by positive lab test.
        • Action: Proceed to Step 2.
  • Step 2: Notification and management of confirmed case.

Note 1: Standard approach

  • Limiting the number of people exposed to the infected animal population to a reasonable minimum.
  • All individuals in contact with animals on infected premises should follow PPE requirements detailed in section 3.3: Managing the human health risk of avian influenza in poultry and wild birds.
  • Withholding prophylaxis with neuraminidase inhibitors (or discontinuing use if already started as part of a strict approach) provided there have been:
    • no human deaths
    • no serious human illness
    • no sustained person-to-person transmission (as confirmed by laboratory tests) confirmed to be linked to that subtype
    • no large numbers of humans affected by common clinical syndrome suspected or confirmed to be linked to that subtype
  • Passive follow-up of persons exposed (provision of information and advised to contact HPT if feeling unwell).

Note 2: Strict approach

  • Limiting the number of people exposed to the infected animal population to an absolute minimum.
  • All individuals in contact with animals on infected premises should follow PPE requirements detailed in section 3.3: Managing the human health risk of avian influenza in poultry and wild birds.
  • Commencing prophylaxis with neuraminidase inhibitors for people already exposed (who have been in close contact with infected animals or contaminated materials from an infected premise) as soon as possible.
  • Advising people who are likely to be exposed as responders to commence prophylaxis in advance of commencement of duties.
  • Active follow-up of persons exposed and/or their close or family contacts, dependent on expert epidemiological and virological advice.
  • Start: Health protection team notified of a suspected human zoonotic influenza case. (Note: This may be triggered by a confirmed animal zoonotic influenza case, per APHA process.)
  • Phase: Pre-assessment actions. Refer to UKHSA guidance on the investigation and initial clinical management of possible human cases of avian influenza with potential to cause severe human disease.
    • Action 1: Isolate the patient in a single-occupancy room.
    • Action 2: Minimize patient contact with staff and other patients.
    • Action 3: Require all staff in contact with the patient to wear correctly fitted FFP3 masks, gowns, gloves, and eye protection, as per the National Infection Prevention and Control Manual (NIPCM).
    • Action 4: Record all essential patient contacts.
    • Action 5: Ensure the patient wears a surgical mask when outside the room, unless patient care (e.g., oxygen therapy) is hindered.
    • Action 6: Start oseltamivir treatment immediately if the patient meets the case definition for zoonotic influenza (ZI).
    • Next: Proceed to Step 1.
  • Step 1: Review clinical criteria.
    • Decision: Does the patient present with any of the following symptoms? Refer to the UKHSA case definition for possible cases: clinical criteria.
      • High temperature at or above 38°C (fever).
      • Acute respiratory symptoms (e.g., cough, hoarseness, nasal discharge or congestion, shortness of breath, sore throat, wheezing, or sneezing).
      • Other severe or life-threatening illness suggestive of an infectious process.
      • Option A: No, the patient does not present with these symptoms.
        • Action: Zoonotic influenza is ruled out on clinical grounds.
        • End: Process ends (no further action required).
      • Option B: Yes, the patient presents with one or more of these symptoms.
        • Action: Zoonotic influenza cannot be ruled out on clinical grounds.
        • Next: Proceed to Step 2.
  • Step 2: Review epidemiological criteria.
    • Decision: In the 10 days prior to symptom onset, has the patient been in close contact (within 1 meter) with any of the following? Refer to the UKHSA list of countries with a known occurrence of high consequence infectious disease and the UKHSA case definition for possible cases: exposure criteria:
      • Live, dying, or dead domestic poultry or wild birds (including live bird markets) in an area affected by zoonotic influenza.
      • Animal case(s) of confirmed zoonotic influenza infection.
      • Human case(s) of confirmed zoonotic influenza infection.
      • Human case(s) of unexplained illness resulting in death from zoonotic influenza-affected areas.
      • Human case(s) of severe unexplained respiratory illness from affected areas.
      • Option A: No, the patient has not had such contact.
        • Action: Zoonotic influenza is ruled out on epidemiological grounds.
        • End: Process ends (no further action required).
      • Option B: Yes, the patient has had such contact.
        • Action: Zoonotic influenza cannot be ruled out on epidemiological grounds.
        • Next: Proceed to Step 3.
  • Step 3: Manage as a possible human case of zoonotic influenza.
    • Actions for Healthcare Professionals:
      • Refer to the NIPCM A-Z pathogens for avian influenza guidance.
      • Ensure isolation and infection prevention control measures for airborne transmission.
      • Confirm all staff in contact with the patient wear correctly fitted FFP3 masks, gowns, gloves, and eye protection.
      • Restrict visitors and maintain a list of all patient contacts.
      • Discuss the case with the local health board’s infectious disease or microbiology specialist, who may consult the Imported Fever Service if needed.
      • If the specialist agrees, collect samples for testing per the Avian Influenza (AI) specific diagnostic pathway (see linked pathway).
      • Continue managing the patient based on clinical needs.
      • Start oseltamivir treatment if not already initiated, alongside other clinically appropriate therapies.
      • Treat linen as infectious and dispose of waste as clinical waste.
    • Actions for Health Protection Teams (HPTs):
      • During working hours, notify the Public Health Scotland (PHS) Influenza Team via phs.respiratory@phs.scot
      • Outside working hours, contact the on-call PHS consultant (refer to the SHPIR for on call rota).
      • Consider convening an incident management team (IMT) for complex cases.
    • Next: Proceed to Step 4.
  • Step 4: Conduct laboratory testing.
    • Action: Send samples for testing according to the Scottish Zoonotic Influenza testing pathway.
    • Decision: What are the lab test results?
      • Option A: Negative results (influenza A negative, influenza A positive but subtyped as Seasonal H3N2/(H1N1)pdm09, or influenza B positive).
        • Action: Report negative results to the local HPT and PHS Influenza Team via phs.respiratory@phs.scot
        • End: Process ends (no further action required).
      • Option B: Positive results (H5 or H7 detected, or influenza A detected but unsubtypeable with relevant exposure for non-H5/H7 zoonotic influenza).
        • Next: Proceed to Step 5.
  • Step 5: Manage as a presumptive positive human case of zoonotic influenza.
    • Actions for clinical diagnostic testing lab:
      • Immediately notify the following of H5/H7 detection or unsubtypeable influenza A with relevant exposures:
    • Actions for health protectionteams:
    • Next: Proceed to Step 6.
  • Step 6: Manage contacts of confirmed case.
    • Action 1: Conduct active follow-up for 10 days post-exposure and provide preventive antiviral treatment (chemoprophylaxis) for:
      • household contacts (more than 15 minutes of face-to-face contact)
      • healthcare workers and hospital visitors who did not wear PPE during contact
      • other close contacts (defined by IMT based on risk assessment)
    • Action 2: Conduct passive follow-up for 10 days post-exposure for:
      • healthcare workers who wore PPE during contact
    • Action 3: IMT to provide advice based on risk assessment and local situation on:
      • Follow-up of air-travel contacts and provision of preventive antiviral treatment (two seats around the index case and all on-board crew).
      • Exclusion of healthcare workers from work.
      • Self-isolation requirements.
  • End: Process ends (follow UKHSA guidance for further management of confirmed cases).

Laboratory investigation pathway for suspected human infections

Download print version

Accessible text version

Decide whether testing is indicated

Follow the investigation and management algorithms for avian influenza virus.

If the patient is considered to be a possible case, the local clinician or microbiologist should contact the duty virologist at:

  • Edinburgh Specialist Virology Centre (SVC)
  • West of Scotland Specialist Virology Centre (WoSSVC)
SVC contact details

In hours (9am to 5pm, Monday to Friday)
0131 536 3373 (choose option 2)

Out of hours
0131 536 1000  (ask for on call virologist)

Email
loth.virologyadvice@nhs.scot

WoSSVC contact details

In hours (9am to 5pm, Monday to Friday)
0141 201 8721

Out of hours
141 211 4000 (ask for on call virologist)

Email
west.ssvc2@nhs.scot

If testing indicated

If the duty virologist agrees that testing is indicated, the local clinician or microbiologist must also notify the local health protection team.

HPTs should immediately notify PHS of all possible case and test results, when available:

Taking samples

The following samples should be taken.

  1. An upper respiratory tract sample (combined nose and throat viral swabs, or nasopharyngeal aspirate).
  2. If obtainable, a lower respiratory tract sample (sputum, or an endotracheal tube aspirate if intubated).
  3. Conjunctival swab (if presenting with conjunctivitis)

Appropriate personal protective equipment and infection prevention and control measures should be used when obtaining diagnostic samples. 

Where possible, samples should be collected in molecular sampling solution (MSS) which inactivates the virus and samples may be handled at CL2 following local risk assessment.

If samples are not in MSS the:

  • WOSSVC or SVC must be contacted for advice
  • samples must be handled at CL3

Where there is an agreed clinical need, a respiratory viral screen should be undertaken locally to prevent delay in treatment of other infections.

If this has been performed, please advise the SVC or WoSSVC to avoid unnecessary repeat testing. 

See also additional considerations for NHS island boards.

All samples meeting the definition of a possible case should be referred for avian influenza testing regardless of the local result.

Sample transfer to SVC/WoSSVC

Once the decision to test has been agreed, the SVC or WoSSVC will liaise with the referring hospital or laboratory, who will arrange transportation of the sample to the SVC or WoSSVC using locally agreed pathways.

Shipment to the initial testing laboratory is by category B transport.

Testing

Influenza A virus testing to be performed at WoSSVC or SVC.

  • Samples are screened for influenza A virus. Positives will be further investigated.
  • Samples that are influenza A virus positive and are negative for H1 and H3 will be tested for H5 and H7
Testing and reporting results

The SVC or WoSSVC duty virologist communicates the result to the referring laboratory.

The referring laboratory is responsible for communicating the result to the HPTs.

All presumptive positive results should be confirmed in writing and by phone.

The local HPT should inform PHS and other relevant parties within their health board of any positive results.

Influenza A is detected but H1 or H3 and avian H5 and H7 subtypes are not detected (influenza A un-subtypable) in a person with exposure to confirmed AI and/or geographical risk.

Strong influenza A positive samples (for example, ct is less than 25) that cannot be subtyped, will be sequenced at the WoSSVC.

  • If sequencing cannot be performed by WoSSVC (for example, due to assay failure), samples are to be sent to the Respiratory Viral Unit, Colindale.
  • If positive for zoonotic flu subtype after sequencing, the actions as for a presumptive positive should be followed.

If samples are:

  • negative for influenza A

or

  • positive for influenza:
    • A(H3N2)
    • A(H1N1)pdm09

The SVC or WoSSVC duty virologist informs the referring laboratory of the results.

The referring laboratory is responsible for communicating this to HPTs.

All results should be confirmed in writing and by phone.

Local HPT should inform PHS respiratory by email.

Templates for HPTs

The following templates have been developed for health protection teams to modify for their use.

Information sheets

These are editable Word documents for you to add your specific details to.

Text for email follow up to contacts

We have provided some suggested text to be used when following up on initial phone conversations with contacts of avian influenza.

We are grateful to NHS Grampian for providing these resources.

Workplace guidance

The Health and Safety Executive provides the following related guidance.

Guidance development method

Guidance development process

The guidance development process followed the agreed development method, health protection guidance: method for guidance development.

Guidance development group (GDG)

A multidisciplinary Guidance Development Group (GDG) exists to produce and update this guidance as necessary.

The GDG had representation from:

  • NHS board HPTs
  • APHA
  • PHS Zoonoses Emerging Infections and Border Health Team
  • PHS Respiratory Team
  • PHS Public Health Microbiology Team
  • Reference laboratories
  • Department of Health and Social Care
  • Scottish Government, Animal Health and Welfare
  • Antimicrobial Resistant and Healthcare Associated Infections
  • Nature Scot
  • PHS Guidance Team

The development process is led by a core team having representation from the Zoonoses Emerging Infections and Border Health, Respiratory and Guidance teams.

The GDG identifies areas where processes and pathways differ from the UKHSA guidance and agree the relevant wording and processes for Scotland, engaging with their stakeholder groups where required.

Regular meetings and communication with the GDG allow discussion around the content and amendments to be agreed on.

Algorithms are developed for human health risk, investigation and clinical management and testing pathways specific for Scotland.

Consultation

The UKHSA guidance and the Scottish documents with algorithms are circulated for consultation with a wide range of stakeholders following any updates. consultation responses are reviewed by the GDG, and the guidance is updated accordingly.

The most recent consultation took place in January 2025 and was open for around 2 weeks.

Approval and review

This guidance has been approved by PHS and SHPN.

In line with agreed approaches, guidance is regularly reviewed within six months of publication.

Variations in the review and approval process

The most recent January 2025 revision did not fully follow PHS agreed guidance development approach.

The key variation was that no assessment of the external guidance or evidence base were undertaken. This variation will be addressed in a future update of this guidance. 

Feedback on this guidance

Comments on how to improve this guidance are welcome and can be sent to PHS Guidance Team at phs.guidance@phs.scot

Equality impact assessment

An equality impact assessment (EQIA) was undertaken to consider any unintended or differential impact or risks arising from implementing the recommendations in the guidance.

For example, how the guidance might:

  • affect children differently to adults
  • be different for people living with different levels of deprivation

Where variable impacts were identified by the GDG or the consultation, the GDG considered the rationale for these and adapted the guidance to mitigate or minimise unfair differences.

Download the EQIA

Glossary

ACDP   

Advisory Committee on Dangerous Pathogens

APHA

Animal and Plant Health Agency

ARHAI 

Antimicrobial Resistance and Healthcare Associated Infection

C&D

cleaning and disinfection

CPH

Consultant Public Health

CPHM

Consultant Public Health Medicine

DEFRA

Department of Environment, Food and Rural Affairs

HAIRS

Human Animal Infections and Risk Surveillance

HCID

high consequence infectious diseases

HPAI

highly pathogenic avian influenza

HPT

health protection team

HSE

Health and Safety Executive

HxNx   

avian influenza of any subtype defined by the Haemagglutinin and Neuraminidase proteins expressed

ILI

influenza-like illness

IMT

incident management team

IP 

infected premises

IPC

infection prevention and control

IPCT

infection prevention and control team

LPAI 

low pathogenic avian influenza

NIPCM

National Infection Prevention and Control Manual

SG AHW

Scottish Government Animal Health and Welfare

PAG

problem assessment group

PHS

Public Health Scotland

PPE

personal protective equipment

SAS

Scottish Ambulance Service

SVC

Specialist Virology Centre

UKHSA

UK Health Security Agency

WoSSVC

West of Scotland Specialist Virology Centre

Last updated: 11 June 2025

Version history

11 June 2025 - Version 1.0

First publication