Guidance

Communicable disease outbreak management guidance: principles to support local health protection systems

Published 21 January 2025

Introduction

Working closely with NHS England (NHSE) and wider system partners, this guidance on the management of communicable disease outbreaks in England has been developed by:

• UK Health Security Agency (UKHSA)
• Association of Directors of Public Health (ADPH)
• Chartered Institute of Environmental Health (CIEH)
• Food Standards Agency (FSA)
• Local Government Association (LGA)   It builds on guidance first developed by Public Health England in collaboration with partner agencies in 2011. It supersedes the interim guidance published in 2023.

Purpose

This guidance provides health protection organisations in England with principles to support local health protection system responses to outbreaks of communicable disease. It aims to prevent harm related to outbreaks of communicable disease.

This guidance:

• should be considered alongside national legislation and policy and is intended to complement disease and organisation-specific guidance
• focuses on routine local level outbreak response, linking to wider outbreak management structures where relevant, including the UKHSA Incident Response Plan (IRP)
• is expected to be made operational through local system and organisation plans and align with other multiagency plans at a local level, including Local Resilience Forum and Local Health Resilience Partnership plans
• should not be considered prescriptive and does not override established and functional operating practice and arrangements at a local system level. However, local systems should be informed by this guidance with a view to developing consistent outbreak management practice over time
• is supported by an accompanying toolkit which contains resources to support further understanding and assist in the implementation of this guidance

Definition of ‘outbreak’

For the purposes of this guidance, an outbreak is defined as either:

• an incident in which at least 2 or more people affected by the same infectious disease are linked by time, place, or common exposure
• a greater than expected rate of infection compared with the usual background rate for the place and time where the outbreak has occurred

Other incidents that can be considered in a similar way to outbreaks include:

• a single case of certain rare or high-consequence diseases, including, but not limited to, diphtheria, botulism, rabies, viral haemorrhagic fever, and polio
• a suspected, anticipated, or actual event involving microbial contamination, for example food, water, and medicine or medical device contamination

Operating framework

The identification and management of outbreaks typically requires a range of capabilities and resources across several organisations. As such, effective partnership working is crucial.

Legal and policy frameworks outline the powers individual organisations have in relation to outbreak management and contribute to the definition of organisational roles and responsibilities enabling coordinated activity. As well as individual statutory responsibility and powers, several organisations also have a collective responsibility to assess, plan and respond to outbreaks as Category 1 responders under the Civil Contingencies Act 2004.

These include:

• local authorities
• emergency services
• NHS trusts and providers
• NHS England
• NHS integrated care boards (ICB) in England
• UKHSA
• port health authorities
• FSA

Roles are not limited to those with legal duties, with other organisations, such as voluntary, community, and social enterprises, playing a leading role in outbreak management in many instances.

There is a summary of the statutory responsibilities and powers of lead organisations with a role in the investigation and management of outbreaks below. 

UK Health Security Agency

In relation to outbreak management, UKHSA’s statutory powers and responsibilities include:   

• a duty to take such steps as the Secretary of State considers appropriate to protect the health of the public in England (Section 2A of the National Health Service Act 2006 (“the 2006 Act”))
• a duty to act as a Category 1 responder in respect of emergency planning and the response and resilience functions for public health (Civil Contingencies Act 2004 (CCA))
• a power to provide a microbiological service in England (paragraph 12 of Schedule 1 to the 2006 Act)
• a power to process confidential patient information without consent under Regulation 3 of the Health Service (Control of Patient Information) Regulations 2002 (as amended) for the recognition, control and prevention of communicable disease and other risks to public health

In relation to infectious disease and outbreaks, UKHSA fulfils its responsibilities through:

• the delivery of expert public health scientific expertise
• data creation, collation, sharing and analysis
• surveillance capabilities and operational response

Further information on UKHSA structures and functions can be found in Toolkit 1: UKHSA structures and functions and Annex A: statutory functions to be exercised by the UK Health Security Agency

Local authorities

Under the Local Government Act 1972, local authorities at upper tier, unitary, and lower tier levels have a statutory duty to provide a range of services to their communities. In relation to outbreak management, this includes responsibilities – with accompanying statutory powers – relating to:

• environmental health
• public health (including Part 2A orders)
• emergency preparedness and response
• housing
• food safety
• food export certificates
• water sampling

‘Environmental health responsibilities’ means providing specialist help and advice on the environmental aspects of outbreaks, including:

• providing  inspections
• collecting samples
• investigating of premises
• enforcement powers
• control orders

Local authorities also have a statutory role and powers described in The Public Health (Control of Disease) Act 1984 to appoint a Proper Officer. The Proper Officer’s powers include the receipt of notifications of notifiable disease, infection, or contamination. In most cases, local authorities appoint a Consultant in Communicable Disease/Health Protection based within UKHSA’s Health Protection Teams (HPTs) as their Proper Officers. In all instances, local authorities should be assured clear processes are in place for notification.

Further information can be found at: Understand how your council works.

Directors of Public Health

Under the Health and Social Care Act 2012, Directors of Public Health (DsPH) have responsibility for exercising the authorities’ responsibilities related to planning for, and responding to, emergencies involving a risk to public health. In practice, DsPH deliver the following in relation to outbreak management:

• advocating for the health of the population and providing system leadership and coordination
• providing expertise and advice on public health issues to local authority elected members and senior officers
• providing the local public with expert, objective advice on health matters including through direct communication and community engagement
• leading work to understand and reduce health inequalities
• working through local resilience forums and local health resilience partnerships (LHRPs) to ensure effective and tested plans are in place to protect the local population from risks to its health
• working with UKHSA and the NHS, through the integrated care partnership (ICP), to ensure arrangements are in place for infection and prevention control (IPC) within health and care settings, reducing vaccine-preventable diseases, and the commissioning of services for response to health protection hazards

Further information can be found at Directors of public health in local government: roles, responsibilities and context.

NHS England

NHS England is the national body for the NHS in England, providing strategic oversight for the NHS and directly commissioning some services. Under section 7A of the NHS Act 2006, NHS England has statutory functions conferred by the Secretary of State to make arrangements and provisions for public health functions, including the commissioning of national immunisation programmes and health services in secure and detained settings. NHS England also has responsibility for ensuring NHS funded organisations in England are prepared for dealing with emergencies in line with the Civil Contingencies Act 2004 (CCA 2004), the NHS Act 2006, the Health and Care Act 2022, and the NHS Standard Contract and assuring the quality of integrated care boards (ICBs) commissioning. For more information see the NHS Emergency Preparedness Resilience and Response Framework.

NHS England (in partnership with other commissioners where appropriate) is responsible for mobilising the clinical response to an outbreak related to its commissioned services.  For vaccination, responsibility for the planning and commissioning of services is to be delegated to ICBs in April 2026 (NHS commissioning: plans to April 2026).

Further information on commissioning arrangements can be found at What is commissioning and how is it changing?

Integrated care boards

ICBs, the statutory bodies established under the Health and Care Act 2022, are responsible for planning and commissioning health services for their local population within a designated integrated care system (ICS). They serve as the local commissioners of NHS-funded community and secondary care services. Additionally, ICBs are tasked with developing integration and collaboration across the ICP and improving population health across the system. In relation to outbreak management, this includes responsibilities for:

• sitting on their LHRP, as part of the NHS system, to prepare and plan for emergencies
• participating as a member of incident management team (IMT) meetings to inform decisions regarding the appropriate response from NHS providers and release of ICB resources
• commissioning many services relevant to outbreak response, including primary care, community, pharmacy, and ICB IPC nursing services; often having a vital role in managing service delivery and tactical coordination of NHS services during incident response
• ensuring pathways are in place for safe and timely clinical care

It is planned that, from April 2026, ICBs will take on responsibility for commissioning of vaccination services, including outbreak response.

Further information on integrated care systems can be found at What are integrated care systems?

Integrated care partnerships

ICPs are statutory committees that form part of a wider ICS. ICPs bring together a broad set of system partners, including:

• NHS organisations
• local government
• community and social enterprises

to collaborate, plan, and improve the health of local people, this includes considering health protection and health protection response. Further information can be found at Guidance on the preparation of integrated care strategies.

NHS provider organisations

Under the National Health Service Act 2006, NHS providers have a statutory responsibility to deliver a range of health services within community and secondary care settings. NHS providers will often have a role in supporting the delivery of outbreak control measures. There is a summary of relevant NHS provider organisation roles in relation to outbreaks below (note: these may vary dependant on local commissioning arrangements).

Primary care medical services (PCMS) are responsible for the providing primary care services to patients registered at their practice, including diagnosing and treating infectious diseases or referring where appropriate. GPs also have a wider role in protecting and improving the health of their local population through essential services, such as routine vaccination.

Out of hours medical services provide assessments, advice, and treatment or referral as required for urgent health problems that cannot safely wait until the next time surgeries are open.

NHS trusts and foundation trusts provide secondary care diagnosis and treatment services for infectious diseases and, where required, implement surge capacity plans to accommodate increased demand for healthcare services.

Community pharmacies can dispense medication for the prophylaxis and treatment of infectious diseases. Some pharmacies also offer vaccination services, point-of-care testing, and consultation services for minor illnesses, either as NHS commissioned services or privately.

Ambulance trusts respond to medical emergencies during outbreaks, provide immediate medical assistance, and safely transport patients to hospital for definitive care. In some circumstances, ambulance services may also be able to support public health interventions such as mass vaccination campaigns and mobile testing units.

School aged immunisation services (SAIS) are commissioned by NHS England to deliver school-aged routine immunisation programmes.

Sexual health services are part of the NHS but are commissioned by local authorities rather than ICBs. Sexual health services are integral to the identification and management of outbreaks of sexually transmitted infections, with specific expertise in contact tracing, screening, vaccination, and patient counselling. More information is available in the national guidance on Investigating and managing outbreaks of sexually transmitted infections.

Food Standards Agency

The FSA is a non-ministerial government department operating in England, Wales, and Northern Ireland responsible for the protection of public health and consumers interests in relation to food and feed. It delivers duties outlined in the Food Safety Act 1990 (as amended) and the Food Standards Act 1999. This includes regulation of food safety and food hygiene systems, direct delivery of official controls in meat, primary dairy, and wine production, and oversee the delivery of controls in other parts of the food and feed system. Food Standards Scotland have a similar role in Scotland.

Concerning the FSA responsibilities in relation to foodborne disease and outbreaks, in practice, this means:

• acting as a point of contact for local authorities in relation to food or feed related outbreaks and incidents (FSA Incidents Team) and providing guidance and information where necessary
• participating in local and national IMTs that are within the scope outlined in Food law Codes of practice, including leading on the coordination of food chain analysis and food industry liaison as well as communicating food safety risks to the general public where required
• acting as the emergency contact point for the International Food Safety Authority Network (INFOSAN) used to exchange information with all international food safety counterparts
• implement necessary emergency measures for imported food in response to serious risks to human or animal health (Trade and Cooperation Agreement)
• designate competent authorities, (that is, local authorities and port health authorities), and official laboratories, in the UK or in a third country, to carry out laboratory analyses, tests and diagnoses on samples taken during official controls and other official activities (AEUL Official Controls Regulation (OCR) 2017/625)
• develop policy and regulations where findings from outbreaks responses identify change is necessary to ensure high level of health protection

Further information can be found at the Food Standards Agency website.

Port health authorities

Port health controls are managed by local authorities who enforce regulations on behalf of central government. The statutory authority for port health authorities is given by the Public Health (Control of Disease) Act 1984, and sets out responsibilities to protect the public, environmental, and animal health of the UK. This includes responsibility for checks on imported food, inspecting ships and aircraft for food safety. It also supports with infectious disease control, and general public and environmental health checks. Through the Association of Port Health Authorities, local authorities work closely together and liaise with the government.

Animal and Plant Health Agency

The Animal and Plant Health Agency (APHA) is an executive agency of the Department for Environment, Food and Rural Affairs (DEFRA). APHA fulfils the functions of the Secretary of State for DEFRA in relation to plant and animal health and welfare in domestic legislation (The Official Controls (Plant Health and Genetically Modified Organisms) Regulations (England 2019) and the Animal Welfare Act 2006). This includes a statutory role in the control and eradication of animal and plant diseases and pests, plant, and bee health, and improving animal welfare, as well as reducing the risk of new and emerging threats. APHA is also responsible for delivering and advising on the statutory services for the implementation of legislation and standards on animal health, plant health, bee health and plant varieties and seeds in England, Wales, and, when appropriate, Scotland.

In relation to outbreak management this includes:

• identifying and controlling endemic and exotic diseases and pests in animals, plants, and bees
• surveillance of new and emerging pests and diseases
• scientific research into bacterial, viral, prion and parasitic diseases, vaccines, and food safety
• acting as an international reference laboratory for many animal diseases
• regulating the safe disposal of animal by-products to reduce the risk of potentially dangerous substances entering the food chain

Further information can be found at Animal and Plant Health Agency.

Health and Safety Executive

Health and Safety Executive (HSE) is an executive non-departmental public body established under the Health and Safety at Work Act 1974 and is the enforcing authority responsible for health and safety regulation for certain premises and activities in the UK. HSE’s primary function is to secure the health, safety, and welfare of people at work, and protect the public from risks to health and safety from work activity. HSE has statutory responsibilities in relation to several settings, including mines, factories, farms, hospitals and schools, offshore gas and oil installations, the gas grid and the movement of dangerous goods and substances, and operating licensing activities in major hazard industries.

In relation to outbreak management, this includes responsibility for

• providing advice, information, and guidance related to health and safety
• carrying out targeted health and safety inspections and investigations
• taking enforcement action as appropriate within the outlined settings

Further information is available at Health and Safety Executive.

Other government departments

Sometimes, other government departments will have a role in outbreak identification and operational management.

Concerning outbreaks in prison and probation settings, HM Prison and Probation Service (HMPPS) has lead responsibility on behalf of the Secretary of State for the commissioning of national prison, probation, and youth offending services.

For outbreaks in immigration removal centres, the Home Office is responsible for oversight and management of these centres.

As such, these departments will play an important role in supporting outbreak management decision making, such as restricting visits or transfers, to ensure effective, efficient, and equitable outbreak management in the context of the need to maintain security within the settings they manage. For further information refer to Management of incidents and outbreaks of communicable disease in secure settings.

Employing organisations

The Health and Safety at Work Act 1974 (HSWA) is the primary piece of legislation covering occupational health and safety in Great Britain. Section 2 of the HSWA places a general duty on employers to ensure, so far as is reasonably practicable, the health, safety and welfare at work of all their employees. This duty is maintained in the context of outbreaks. More information about the HWSA can be found on the HSE’s website: Health and Safety at Work Act 1974 – legislation explained.

Further information on the legislation supporting health protection preparedness, response, and enforcement can be found in Toolkit 2: summary of health protection legislation .

Planning and preparedness

Planning and preparedness are essential to ensuring timely and effective local outbreak detection and management. Effective preparedness can also support action to reduce the likelihood of outbreaks, for example supporting targeted vaccination uptake or enhancing infection prevention and control.   

Effective outbreak management requires collaborative planning and preparedness across local systems. This may include:

• developing outbreak management plans
• establishing outbreak commissioning arrangements
• notification pathways
• joint training and exercising
• data sharing agreements

All agencies with a statutory responsibility for planning for outbreaks and incidents should ensure the preparedness of their delivered and commissioned services to respond to outbreaks. This includes considering their ability to rapidly adapt to evolving outbreak-related needs in a coordinated way. A template Memorandum of Understanding and supporting guidance are available via the Future NHS Collaboration Platform to support local interoperability arrangements.

DsPH, working through local resilience forums and local health resilience partnerships, have a statutory role to ensure effective plans are in place and tested. This role includes seeking assurance around the consideration of local health needs, as well as ensuring agreement around funding and local roles and responsibilities. DsPH should be able to escalate any concerns as necessary with the appropriate partner organisations, including the NHS and UKHSA.

ICPs should consider health protection within their integrated care strategy to deliver improved outcomes for the population and communities that they serve. This may include the commissioning of services for health protection response such as testing, vaccination and prophylaxis and IPC arrangements.

Outbreak management process

The outbreak management process begins with the identification of a potential outbreak. It is followed by an initial investigation and risk assessment to establish if an outbreak is occurring and inform initial actions. Once declared, the IMT decide how to manage the outbreak, who should manage it, how the outbreak might be investigated and controlled, whether to escalate, and how to do outbreak-related communications. All of these decisions are revisited until the end of the outbreak. Figure 1 provides a visual representation of the outbreak management process.

Figure 1: outbreak management process

Note: a dynamic risk assessment can be requested at any time via the UKHSA National Response Centre, in order to determine the appropriate level of incident response required within UKHSA.

Figure 1 is a flowchart that provides an overview of the outbreak management process and consists of a number of steps and actions.

1. Incident notified or identified
2. Initial response and investigation undertaken
3. Is the incident an outbreak?

If yes, outbreak declared, go to step 4.

If no, review as required. No further action required unless a change in the incident occurs and an outbreak is confirmed, repeat step 3.

4. Is an incident management team (IMT) required?

If yes, incident management team established, go to step 5.

If no, review as required and go to step 6. If a change in the incident occurs and an incident management team is established repeat step 4.

5. Undertake 3 actions

• Investigation: consider epidemiological, microbiological, environmental and veterinary investigations
• Control measures: consider source and mode of spread, protect persons at risk and monitor effectiveness
• Communications and engagement: consider incident management team minutes, communications protocols, engagement plan and media

Go to step 6.

6. End of the outbreak

• declare outbreak over
• undertake constructive debrief and lessons identified
• produce final outbreak report
• action lessons identified

Outbreak identification

Notification and surveillance

To detect outbreaks, information regarding confirmed or suspected diagnoses of infectious disease and the pattern of their distribution is required. As such, infectious disease notification is a vital process to support outbreak detection.  

‘Notification of infectious diseases’ is the term used to refer to the statutory duties for reporting notifiable diseases in the Public Health (Control of Disease) Act 1984 and the Health Protection (Notification) Regulations 2010 (HPNR). Registered medical practitioners (RMPs) have a statutory duty to notify the ‘Proper Officer’ of the local authority of suspected cases of certain infectious diseases. In practice, the ‘Proper Officer’ role is typically held within UKHSA HPTs.

All laboratories in England performing a primary diagnostic role must notify UKHSA on the confirmation of a notifiable organism.

Organisations with a role in the notification of infectious diseases should ensure systems facilitate compliance with the HPNR. Organisations and wider professionals also have a duty to notify potential outbreaks or situations of concern to UKHSA.  High risk settings such as healthcare, adult social care, prisons, and inclusion health settings should be clear as to their mechanisms for prompt notification and for seeking support in outbreak identification and management. 

Further information can be found in Notifiable diseases and causative organisms: how to report.

Recognising potential outbreaks

Potential outbreaks will typically be identified:

• in the setting where the outbreak occurs (for example a care home)
• in services with regular population contact (for example A&E departments)
• through the routine operational and surveillance work of UKHSA HPTs and Field Services teams and local authorities

However, other teams within UKHSA, such as national UKHSA specialist teams, or other organisations, such as the FSA, may be the first to identify signs of an outbreak.  

When a potential outbreak is identified, the identifier should notify local UKHSA HPT covering the area where the outbreak has occurred immediately. Where the location of an outbreak is unknown, the notifying organisation should inform their local HPT. Details of local health protection teams in England can be found at Find your local health protection team in England. 

Initial investigation

Once an outbreak is suspected, investigation will usually begin within 24 hours but may vary dependent on the nature of the suspected outbreak. To support this process, UKHSA HPTs, where leading the outbreak detection process, should rapidly contact relevant parties to permit a timely initial risk assessment. This initial assessment should provide clarity regarding outbreak status, the potential for harm, and the nature of the response required.  Further information on outbreak risk assessment can be found in Toolkit 3: UKHSA risk assessment.

Important objectives of initial outbreak investigation are to:

• define and identify cases, describing their distribution according to important attributes, such as time of infection, outbreak location, and characteristics of individuals infected. This should include a consideration of diagnostic certainty
• develop a provisional hypothesis regarding the cause, vehicle, and source of the outbreak (an outbreak hypothesis) and, where appropriate, evaluate this hypothesis using analytical techniques
• establish if any concerning outbreak attributes are present, such as rapidly increasing numbers of case or the presence of severe or atypical disease presentations
• develop an understanding of the context surrounding an outbreak, including structural and individual vulnerabilities and risks of inequitable patterns of harm

Verifying diagnoses is likely to involve the collection of clinical or environmental samples and additional epidemiological information.

Alongside initial outbreak investigation, it is important to promptly implement outbreak control measures according to the relevant guidance.

Declaring an outbreak

To make early collaboration possible, the relevant lead agency should promptly notify partners who may be impacted or may be involved in outbreak management as soon as an outbreak is identified. In some cases, they should do so even before it is confirmed. Further information on IMT leadership can be found in Toolkit 4: the incident management team.

Initial sharing should include a preliminary discussion between the relevant stakeholders for the geographical areas affected, for example:

• UKHSA
• ICBs
• DsPH
• Regional NHS England teams

Depending on the nature of the outbreak, the approach to initial sharing should also include, where appropriate, engagement with:

• the setting where the outbreak has occurred or, where appropriate, agencies representing the affected population
• providers and commissioners of any services likely to be impacted by the outbreak, such as the NHS and the local authority

On declaring an outbreak, consider regarding the need to notify or engage with relevant regulatory bodies, such as the Care Quality Commission (CQC) or the Medicines and Healthcare Products Regulatory Agency (MHRA).

Coordination and escalation

Incident management teams

An IMT is a multi-disciplinary group responsible for investigating and managing an incident or an outbreak. Further information, including typical IMT aims and objectives and the roles within an IMT, can be found in Toolkit 4: the incident management team.

An IMT should be established when an incident or outbreak presents a significant risk to health; this is usually when there are:

• one or more cases of serious communicable disease, which are diseases with high morbidity or mortality rates
• instances of atypical or concerning disease presentation
• a large number of cases
• cases identified over a large geographical area suggesting a dispersed source
• significant vulnerabilities or risks of inequitable harm

Other factors which may indicate the need for an IMT include:

• significant public, political, or reputational interest
• safeguarding concerns related to an outbreak
• greater coordination between agencies required to support outbreak management

Typically, a decision to call an IMT would sit with the lead organisation, most often UKHSA.  However, any organisation with a role in the management of an outbreak may request an IMT where an outbreak has been declared. 

Routine incident management

IMTs are not always required to support the management of outbreaks, for example in instances of uncomplicated low risk outbreaks in a single setting. In such instances, outbreak management will usually be led by UKHSA HPT’s acute response service or by other relevant lead agency services, working in partnership with other organisations, such as local authorities and NHS (providers or commissioners), where appropriate. Where an IMT is not convened, close liaison between the lead organisation and relevant partners should be maintained to ensure situational awareness. Decisions regarding the convening of an IMT should be recorded, along with risk assessments informing such decisions. The lead organisation should continue to review the need for an IMT at regular intervals.

Further information on the management, structures, and roles within an IMT can be found in Toolkit 4: the incident management team.

Escalation

In instances where it is deemed that outbreaks cannot be managed using locally available resources and processes – or where national coordination is required – outbreak incident management may be escalated within organisations. Within UKHSA, the UKHSA dynamic risk assessment, led by UKHSA National Response Centre (NRC), is used to determine the level of incident management required and support the activation and allocation of national resources, including the establishment of a UKHSA agency-wide response.

It is recognised that triggers for escalation across agencies will differ, as will de-escalation triggers and timings.

Arrangements for outbreak management across geographical or organisational boundaries within the UK

IMTs have a role in determining the need for, and appropriate approach to, cross border collaboration in relation to outbreak management. 

Outbreaks crossing geographical or organisational boundaries within England – partners should work collaboratively with neighbouring organisations and a decision made as to which organisation will act as lead.

For routine incidents the lead agency will normally be the UKHSA HPT where the outbreak is first identified or where most cases reside.

For more complex cross-boundary outbreaks, incidents should be escalated in line with existing arrangements, using mechanisms to support coordination, such as local resilience forums or organisational major incident response plans.

For outbreaks crossing national borders within the UK, UKHSA is responsible for providing information and services to support a coordinated and consistent UK public health response.

Where there are serious or widespread food or feed related outbreaks (for example affecting multiple local authorities), UKHSA and FSA will work in collaboration. This may include UKHSA acting as incident lead with FSA supporting coordination and leading food safety approaches and enforcement in accordance with relevant food regulations and statutory Codes of Practice.

Working across the 4 Nations of the UK

Whilst health protection is a devolved competency, both the IHR and the Health Security (EU Exit) Regulations 2021 ensure that all parts of the UK coordinate on data sharing, epidemiological surveillance, and their approach to the prevention and control of serious cross border threats to health.

International outbreaks

Under the International Health Regulations 2005 (IHR), the UK governments, including the devolved administrations, have designated UKHSA to act as the National Focal Point (NFP) for all UK territories (this includes England, Wales, Northern Ireland, Scotland, Crown Dependencies, and the UK Overseas Territories). As the NFP, the UKHSA is responsible for reporting incidents of potential international significance to the World Health Organization (WHO). Events that meet the definition for a serious cross border threat to health [note 1] will also be reported to the European Commission under the Health Security (EU Exit) Regulations 2021.

A “serious cross-border threat to health” is defined as a life-threatening or otherwise serious hazard to health of biological, chemical, environmental or unknown origin. It spreads, or entails a significant risk of spreading, across the borders of at least one member state and the United Kingdom (UK). It may need a coordinated response by the UK authorities to ensure a high level of human health protection. A high level of human health protection is defined by the Public Health Protection and Health Security Framework Outline Agreement (known as the Common Framework), which is a memorandum of understanding between the governments of the 4 Nations of the UK and their public health agencies. This definition includes events that may constitute public health emergencies of international concern under the IHR.

If a food or feed-related source is implicated, the FSA is responsible for notifying the INFOSAN (International Food Safety Authorities Network) Emergency Contact Point (ECP) and having a function in place to be notified by other INFOSAN ECP and the RASFF network, in the European countries.

Outbreak investigation

Outbreak investigations serve to inform outbreak control and communication strategies. An investigation plan should be agreed at the earliest possible point, usually after confirmation of the outbreak. Outbreak investigations should seek to describe outbreak risk, and its determinants, and identify the impact of outbreak control measures. The approach to outbreak investigation will vary depending on circumstances. Toolkit 5: investigation protocol provides an outline of a typical investigation protocol.

Timely access to accurate information throughout the outbreak management process is essential to inform risk assessment, enabled by early open communication between partners and stakeholders. Information used to inform a risk assessment should include:

• background information, including context and the process of identification
• a timeline of events
• clinical information about the cases
• epidemiological information about the disease or infection and the outbreak being investigated
• microbiological information about the known or probable infectious agent
• clinical or public health guidelines for the treatment and prevention of the infectious disease in question
• information about the wider context surrounding the outbreak, including vulnerabilities and risks of inequitable harm, which may impact on outbreak dynamics and decisions regarding the approach to outbreak management

Different organisations use different risk assessment frameworks; the choice of framework should depend on the circumstances and be agreed at the IMT. An example of a risk assessment framework which may be used is provided in Toolkit 3: risk assessment.

Case definitions

An initial case definition should be agreed by the IMT or outbreak lead as early as possible, based on what is known about the infection and population at risk, relevant national guidance, and epidemiological data. The case definition should be regularly reviewed and revised as necessary.

Case finding

Case finding involves work to identify those infected by a pathogen linked to an outbreak. Case finding is crucial for accurate epidemiological study and risk assessment and to enable timely treatment and wider outbreak management activities. Approaches to identifying cases linked to an outbreak include:

Contact tracing

Contact tracing is the process of identifying persons who may have come in to contact with a case or exposure in the environment and assessing the risk of transmission to those individuals. Contact tracing is normally undertaken by UKHSA HPTs. However, in some circumstances, others may undertake or support contact tracing work, including:

• local authority environmental health officers
• specialist clinicians (for example, tuberculosis nurses and sexual health services)
• staff in health and justice settings
• provider infection prevention and control teams
• local authority public health teams
• general practitioners

In NHS healthcare contexts, contact tracing responsibilities for individuals exposed within an NHS setting are with the relevant NHS body.

Clinical assessment

Clinical assessment by medical professionals is vital during incidents and outbreaks of infectious diseases to support accurate diagnosis, an important aspect of case finding, and to inform approaches to treatment of affected individuals. Clinical assessment is typically undertaken by NHS healthcare staff. ICBs, working with NHS service commissioners and providers, should ensure safe pathways, including policies on transport, isolation, and decontamination, are in place for clinical assessment and management in the context of an outbreak, including where high-consequence infectious disease may be suspected.

Testing suspected cases 

Where individuals are suspected to be infected by a pathogen linked to an outbreak, laboratory testing is often important to confirm infection status and, where possible, identify if the detected pathogen is genetically linked to the outbreak. Typically, sample collection occurs within the NHS services or is supported by local authority environmental health teams and testing performed by local laboratories or UKHSA microbiology microbiology and food, water and environment laboratory services. UKHSA reference laboratories may also be used to confirm test results and provide additional information on the pathogen, including genetic typing. UKHSA reference laboratories may also be required to safely test samples linked to high consequence infectious disease. In instances of animal infection, APHA hold responsibility for conducting sampling, testing, and interpretation of results. Local systems should ensure safe and effective pathways are in place for collecting, storing, and transporting specimens for testing.

Testing asymptomatic individuals with known risk

Testing of asymptomatic individuals, where there is a suitable, validated test or method, can involve using a range of approaches, including self-swabbing or self-testing of individuals or coordination of larger scale testing in workplaces or community settings. Testing arrangements will depend on the nature of the outbreak; however, large-scale testing will usually require multi-agency coordination or input, often involving NHS, local authority, and UKHSA HPT and public health microbiology services input. In some large or complex incidents, the UKHSA Rapid Investigation Team (RIT) may provide initial support while services are being developed.

Enhanced surveillance

Enhanced surveillance systems involve the collection of additional information to identify outbreak sources and support the identification of individuals meeting the agreed case definition. Information collection for enhanced surveillance purposes will often be undertaken by UKHSA HPTs in collaboration with UKHSA Field Services teams or environmental health officers. UKHSA has the power to process confidential patient information without consent under Regulation 3 of the Health Service (Control of Patient information) Regulations 2002 (as amended) for the recognition, control, and prevention of communicable disease and other risks to public health.

Understanding outbreak characteristics

Small scale, non-complex, outbreaks may require minimal technical expertise to undertake analysis and interpretation of data. However, more complex analysis is often required to inform decision-making regarding outbreak control measures and communication. The approach to this analysis can be divided into two types: 

Descriptive Epidemiology: this involves describing the number of cases, in line with case definitions, according to distribution across time and space. Typically, descriptive epidemiology also describes outbreak patterns according to important characteristics, for example:

• age
• sex
• disease severity
• important epidemiological links, such as known sexual contact or attendance at certain settings

UKHSA Field Services teams generally lead on the production of descriptive epidemiology outputs. Basic descriptive epidemiology should be updated and reviewed at each IMT meeting.

Analytical studies: are used to test outbreak hypotheses. Analytical studies are typically developed using both descriptive epidemiology and existing knowledge regarding the pathogen in question and relevant contextual factors. Where analytical studies confirm an outbreak hypothesis, this can support outbreak communication and inform outbreak control measures. UKHSA Field Services teams will usually lead on the design and implementation of analytical studies, requesting support from other UKHSA teams as required. IMTs should consider the resource implications of undertaking analytical studies against the likelihood of clear outcome and the value of analytical epidemiology evidence. 

For hypothesised causes of contaminated food or drinks, cohort and case control studies are used to assess the relationship between exposure to a risk factor and the occurrence of illness. The appropriate study design will depend on the nature of the outbreak. Field Services or other national experts within UKHSA can provide expert advice and support on study design and will usually lead the development of the protocol. A template investigation protocol can be found in Toolkit 5: investigation protocol.

Depending on the incident, further microbiological and environmental investigations may be undertaken.

For incidents with direct human-to-human transmission routes, specialist transmission dynamic modelling may be required. Expertise within the UKHSA modelling team is available in these situations to assist the IMT.

Microbiological investigations: where indicated this may include a range of specialist methods, such as molecular typing or extended antimicrobial susceptibility testing. Typing results can identify likely transmission links or subclusters, and identify when strains or cases are not linked, which will help inform the outbreak control strategy. These investigations may be performed using human, animal, food, animal feed or environmental samples. The potential role of reference microbiology to help identify sources and transmission links should be considered.

Environmental investigations, including food chain analysis and investigations: in some circumstances, there can be a need to characterise risk of harm from environmental sources of infection and determine if control measures focused on the environment or food chain are required. Local authority environmental health officers and veterinarians in FSA approved establishments often play an important role in environmental investigation, including the collection of samples to support microbiological investigation where required. However, in certain circumstances, other agencies may lead on environmental investigation. UKHSA Food Water and Environmental Microbiology Services will be able to provide advice and support in relation to sampling and testing, and in complex situations, may be able to offer on-site sampling support.

Other sources of information: to support understanding of outbreak characteristics, qualitative approaches – including engaging communities and population groups – may also be used to develop an understanding of barriers and facilitators to effective and equitable outbreak management.

Outbreak control measures

Outbreak control measures aim to prevent and reduce infection transmission and minimise outbreak-related harm. Outbreak control measures will vary according to the specific infection and population groups involved. Control measures can include provision of information to support individuals to make decisions on how to avoid infection transmission, provision of physical interventions, such as delivery of vaccines or antibiotics (including chemoprophylaxis), and advising limits on individuals’ contact with others.

The IMT plays a crucial role in enabling informed agreement on control measures and approaches to delivery. Decisions on outbreak control measures should be informed by relevant national guidance and findings from outbreak investigation and conform with any relevant legislation. Decisions should also consider the population or organisation impacted, including consideration of acceptability and feasibility, and the risk benefit balance of any actions. IMTs should therefore seek to ensure input from individuals or groups representing the populations or settings impacted.

Further information on the management of outbreaks in specific settings can be found in Toolkit 6: principles for the management of outbreaks in specific settings.

Implementing outbreak control measures

As a general principle, the responsibility for implementing and funding outbreak control measures will typically sit with the organisation normally responsible for the delivery or commissioning of the intervention applied. Clarity on funding responsibility should be sought at an early stage when determining approaches to outbreak control; however, this should not delay action. ICBs, through the development of their local multi-agency outbreak plan, should clarify the sources of contingency funding for outbreak response.

Where possible, interventions should be delivered using ‘business as usual’ resources and processes. This might not be possible. For example where management is required at scale, or adaptions are required to meet the needs of groups with poor access to mainstream services. When it is not possible, IMTs should rapidly:

• act to describe the need for the scaled or novel delivery approaches
• identify any additional costs
• reach agreement on the operational and financial responsibility for outbreak control measures.

Outbreak control measures – roles and responsibilities

The roles and responsibilities of relevant organisations in relation to outbreak control measures may vary depending on the nature and context of outbreaks and local arrangements; however, general principles are provided below.

DsPH and ICPs have a role in ensuring local arrangements support the mobilisation of response across a range of possible outbreak control measures and population groups.

UKHSA is responsible for providing expert evidence-based health protection advice and guidance and epidemiological intelligence to inform outbreak control decisions, in addition to supporting outbreak monitoring and the evaluation of outbreak management activity. UKHSA, whilst often the lead organisation within outbreaks, does not typically hold responsibility for the funding and provision of outbreak control measures beyond the provision of advice and guidance to cases and contacts and settings.

Local authorities are responsible for environmental health interventions (lower tier or unitary authorities). This may include securing mitigations to reduce outbreak risk where the local authority is the enforcing authority or where it is the primary authority for companies that operate across local authority boundaries. This may involve:

• identification, removal and safe disposal of contaminated food
• disinfection and decontamination of infective material
• ensuring infection control advice is implemented in settings
• lead coordination of action with private owners and agreeing financing of required action

Local authorities (upper tier or unitary authorities) also have a responsibility for contributing to outbreak response, where appropriate, through their commissioned services, such as sexual health services and contributing to the identification of additional support including amongst the local voluntary, community and social enterprise sector.

DsPH, and their public health teams, play a crucial role in supporting outbreak control decision making through the provision of insights into local populations, including vulnerabilities and inequalities, and local factors which might affect transmission and the effectiveness of outbreak control measures. Additionally, local authority teams may work with communities or settings to support communication and implementation of outbreak control decisions.

ICBs are responsible for the planning and deployment of NHS resources as part of its locally commissioned services in response to an outbreak. Each ICB should develop a robust multi-agency plan for outbreaks that inform the delivery of outbreak control measures which:

• is agreed by the local authority, UKHSA HPT, LHRP and NHS England regional team
• clarifies local responsibilities across all parties
• clarifies sources of contingency funding to support outbreak response
• addresses how underserved populations will be reached, building on the community engagement and outreach models, to ensure outbreaks do not exacerbate health inequalities
• aligns capacity with other services by working with other organisations
• ensures pathways are in place to enable public health recommended interventions to be delivered in the local community for predictable scenarios, including the provision of post exposure chemoprophylaxis, post-exposure and reactive vaccination, and immunoglobulins
• ensure pathways are in place for the safe management of high consequence infectious diseases

NHS England is responsible for the planning and deployment of NHS services as part of its nationally and regionally commissioned services, including healthcare for those in health and justice settings and vaccinations which form part of the NHS public health functions (section 7A) agreement 2021 to 2022. It is planned that ICBs will take on responsibility for commissioning these services following delegation in April 2026.

FSA are responsible for awareness raising, risk analysis, and working with food and feed trade associations in instances where outbreaks are related to, matters of food safety concern. FSA are also responsible for the delivery of official controls where it is the competent authority, as opposed to the local authority in premises approved by the FSA.

APHA typically holds responsibility for taking animal-related outbreak control actions as indicated, including restrictions, culling if applicable, tracings, and surveillance where indicated. 

Provider organisations, such as care or prison settings, have a role in supporting the delivery of outbreak measures where appropriate. This may include activities such as supporting with isolation, infection prevention and control action, and enabling access to prescriptions.

Roles and responsibilities in relation to specific outbreak control measures

Beyond the general principles for roles and responsibilities for relevant organisations outlined above, roles and responsibilities concerning specific outbreak control measures are considered below:

Personal Protective Equipment: the procurement, provision, and funding of personal protective equipment (PPE) would typically sit with the organisation making use of PPE in the delivery of its services (for example, visitors in social care settings).

Vaccination responsibility for funding and deployment of vaccination is dependent on the nature of the vaccination and relevant commissioning arrangements. For vaccination, which is part of an NHS routine vaccination programme, responsibility would typically currently sit with regional NHS England teams. Responsibility for funding and deployment of vaccination which does not form part of a routine vaccination programme will vary depending on local commissioning arrangements. Vaccination delivery method should consider the most appropriate approach for the population at risk.

Clinical treatment and chemoprophylaxis: antimicrobial agents are used to prevent or treat infections. In outbreak situations, these may include antibiotics, antivirals, and antiparasitics. Prescription of antimicrobial treatments to patients with suspected or confirmed infections is part of normal clinical practice for GPs and other medical professionals. However, during outbreaks and incidents, demand for treatments may require additional prescribing capacity and alternative approaches may be indicated. Antimicrobial treatment and prophylaxis may be recommended by the HPT based on national guidance or expert advice. ICBs should ensure that local pathways are arranged for prescribing and dispending antimicrobial treatment and chemoprophylaxis to cases and contacts of infectious disease, including weekend provision where appropriate.

Infection Prevention and Control (IPC) services responsibility for funding and provision of community IPC will typically sit with the local commissioner of the service, with approaches to commissioning varying across areas.

Restriction of an individual’s movements: advice to restrict contact with others is often used as an infection control measure to reduce the spread of infection. Part 2A orders (applied for and made under the Public Health (Control of Disease) Act 1984)) provide local authorities with additional powers to manage a person or item that may cause significant harm to human health from infection or contamination, where other interventions have either failed or are not suitable. Prior to the implementation of enforcement, IMTs should consider how to support individuals to isolate as part of outbreak control measures, including consideration of the feasibility and suitability of an isolation environment and the wider health and wellbeing and safeguarding needs of the individual and any dependents.

Outbreak Communication

Public communications and community engagement

Communications and community engagement are an important part of outbreak management. They enable populations to be informed and supporting individuals to take action to reduce the risk of transmission and harm in the context of an outbreak.

Communications approaches should be considered at the following points within an outbreak:

• following recognition of a potential outbreak
• when relevant findings are identified through outbreak investigation
• at points of material change in outbreak management approach where members of the public or other stakeholders need to act to minimise risks to health
• once the outbreak investigation has concluded

Public communication and community engagement should be undertaken in collaboration with relevant system partners and the IMT, using the expertise of relevant agencies and ensuring consistent and timely messaging. A lead organisation for communication should be agreed at an early stage of outbreak management, usually the organisation with lead responsibility for management of the outbreak.

A communications strategy, incorporating consideration of behavioural sciences, should be agreed to promote coherence and reduce duplication of effort. The communication strategy should consider the risks (including stigmatisation) and benefits of proactive versus reactive media engagement. Communication strategies should include consideration of community engagement approaches to ensure that the needs of all population sub-groups are understood and addressed. Where IMTs have been convened, the communications strategy should be reviewed at each meeting. 

Individual IMT partners’ specific legal obligations and principles of transparency should be considered in determining communications strategies.

Community engagement should go beyond solely delivering top-down information to the public and involve listening to, recognising, and responding to community concerns. Approaches to communicating with communities should use credible communicators to build and maintain trust and involve collaboration with community organisations, use co-creation to ensure messages are relevant and use inclusive language. Wherever possible, evaluate community engagement approaches to understand their effectiveness and to inform future approaches.

Local authorities should take a lead role in facilitating community engagement and effective communication. Voluntary groups, community groups, charities, and social enterprises can play an important role in providing specialist knowledge of local population needs, acting as trusted points of contact for information dissemination and supporting the development and dissemination of communications which meet the needs of the population. In outbreaks requiring a vaccination response, UKHSA, NHS England, ICBs, and local authorities should work in collaboration to ensure effective messaging is delivered to relevant population groups, proportionate to the scale of delivery needed.

Further information on communications and media approaches is included in Toolkit 7: communications and media approaches.

System communication

It is essential that effective communication is established between all members of the IMT and relevant partners.

Standard and local communications protocols should be followed for the dissemination of critical information within UKHSA and with IMT members as necessary, including regular briefing notes (for standard and enhanced incidents) or situational reports (SITREPs). 

The IMT chair and IMT members are responsible for ensuring effective communications across relevant agencies. Relevant communication teams, such as those in the NHS, local authority, and UKHSA, should work in collaboration to facilitate consistent and effective messaging to system partners.

General principles:

1. Where communications relate to the media or include public facing materials, UKHSA communications leads will be responsible for ensuring important partners, for example the Department of Health and Social Care (DHSC), are informed as required. Where the cause of an incident is suspected to be linked to food or animal feed, this lead role will often be undertaken by the FSA. The FSA Boards or executive should be informed where ministerial or senior officials communications occur related to food or animal feed incidents.
2. Communications to local elected members will be led by the relevant local authority and DPH.
3. Communications to NHS providers will be led by the relevant commissioner
4. Communications and information sharing must be undertaken in line with data protection legislation as outlined in Toolkit 2: summary of health protection legislation (section 2.3).

If the approach to outbreak management is escalated, the approach to outbreak communications should be adapted accordingly. 

Minutes should be taken for all IMT meetings and circulated to members and other relevant stakeholders as agreed during the meeting. Minutes should include a log of attendees, a copy of risk assessments, decisions taken, and actions agreed (see Toolkit 4: the incident management team). All documentation relating to an outbreak will be maintained by the lead organisation, noting reference numbers for relevant linked records related to the management of the outbreak. Take caution in the handling of personally identifiable information and commercially sensitive information in the management of outbreaks. More information on leading considerations relating to confidentiality in outbreak reports can be found in Toolkit 9: final outbreak investigation report.

Health inequality and ethical considerations

Ethical and equity aspects of decision making should be considered throughout outbreak preparation and management processes, recognising public authorities’ duties under the Public Sector Equality Duty (PSED) and the Equality Act 2010. These duties include the need to pay due regard to eliminate unlawful discrimination, harassment, and victimisation, advance equality of opportunity, and foster good relations between different parts of the community.

Several barriers are known to exacerbate vulnerability to hazards to health, including barriers around accessing and understanding information as it is typically presented, barriers to taking action to reduce exposure risk, and barriers to accessing healthcare. Adverse impacts of actions taken as part of outbreak management and how these might be inequitably distributed should also be considered; for example, for somebody with unstable employment, isolation may risk loss of income. Consideration of vulnerability should include potential for, or the presence of, safeguarding risks and any action required to address these.

To support structured consideration of ethical and equity aspects of outbreak management, UKHSA and NHS England use the CORE20PLUS framework. This framework promotes active consideration of populations who are known to experience increased risk of exposure to pathogens, increased susceptibility when exposed to pathogens, variations in access to control measures, and who may have different perspectives on the acceptability of control measures. Populations to consider include, but are not limited to:

• the most socio-economically deprived 20% of the population, as identified by the Index of Multiple Deprivation (IMD)
• people experiencing poverty who are not living in areas classified as the most socio-economically deprived 20% by IMD. For example, some coastal communities and areas with pockets of deprivation amongst relative affluence
• some people with protected characteristics as defined by the Equality Act 2010 (age, disability, gender reassignment, pregnancy and maternity, race, religion or belief, sex, sexual orientation). For example, ethnic minority communities, people with a learning disability and autistic people, and LGBTQ+ people (lesbian, gay, bi, trans, queer, questioning and asexual)
• people with long term health conditions, including mental health conditions, that place them at increased risk of infection or increased vulnerability to external health hazards
• people providing and receiving social care (adults and children)
• inclusion health groups [note 1]
• people whose first language is not English

Note 1: inclusion health groups include:

• people experiencing homelessness
• people with drug or alcohol dependence
• asylum seekers
• refugees and undocumented migrants
• Gypsy, Roma and Traveller communities
• sex workers
• people in contact with the justice system
• victims of modern slavery
• other groups often experiencing social exclusion

The groups include both adults and children. Those in inclusion health groups are often at greater risk of experiencing very poor health. Contributors to this risk include stigma and discrimination, and poor access to, and experience of, healthcare and other services

Whilst written with reference to decision making during a Pandemic, the ethical framework contained within ‘Pandemic flu planning information for England and the devolved administrations, including guidance for organisations and businesses’, provides a useful reference framework for IMTs.

Evaluation measures

The evaluation of outbreak control measures during the management of an outbreak can provide valuable information on effectiveness, cost-effectiveness, and adverse impacts. In addition to undertaking descriptive epidemiology, and using analytic techniques to test outbreak hypotheses, IMTs may consider additional evaluation or research activity. If deciding to undertake additional evaluation or research, IMTs should aim to define the primary outcome measures for evaluation during the early stages of investigation to support data capture, and seek support from relevant teams within UKHSA (such as Field Service, Evaluation and Epidemiological Science or Behavioural Science and Insights).

Declaring an outbreak over

The IMT, or lead organisation where no IMT is convened, is responsible for determining when the outbreak is over, informed by on-going risk assessment. Agreement that an outbreak is under control should include consideration of whether there is:

• an observed stabilisation or a decline in case numbers (a return to expected levels)
• a decrease in case numbers to levels which can be managed through routine clinical and public health services
• high coverage of effective interventions, such as vaccination, in the population at risk, where indicated

Rationale for the decision should be documented by the IMT or lead organisation where relevant. The IMT should consider the need for a period of enhanced surveillance following the end of an outbreak to provide assurance that any resurgence will be closely monitored.

Debrief and lessons identified

Debrief or lessons identified processes are usually led by the outbreak lead. In most cases this would be UKHSA and undertaken in line with the UKHSA IRP. Debriefs or lessons identified processes should involve agencies involved within the IMT and outbreak response, and learning should contribute to existing organisational or system planning. 

For long running incidents, it is useful to implement a periodic debriefing approach via an in-action review. This allows the IMT to rapidly identify, and possibly rectify, any issues or lessons over the course of the incident, as opposed to waiting for the recovery or stand down phase.

The lessons identified process included as part of a debrief should follow those of the lead agency. A debrief facilitator who was not directly involved with the incident should support this process. Further information on the UKHSA debriefing and lessons identified process can be found in Toolkit 8: UHKSA constructive debriefing and lessons identified.

Outbreak report

Where an IMT has been held, the IMT may request an outbreak report. This is best practice where outbreak management has been complex, or where it is felt there is appropriate learning to be shared. Toolkit 9: final outbreak investigation report contains a standard format for the final outbreak report and guidance regarding legal considerations in the development and disclosure of outbreak reports. The IMTs decision on whether to complete and outbreak report, should be recorded.

Audit

To assist the audit of this guidance, a set of standards for managing outbreaks is provided in Toolkit 10: auditable standards. Any audit against the standards should be included as part of the outbreak report.  Audit of the standards will be undertaken by UKHSA and support the continual review of the guidance.

Feedback

You can provide feedback on the Communicable Disease Outbreak Management Guidance and associated toolkits at cdomfeedback@ukhsa.gov.uk or by completing the short survey: