The concept
Clinical vulnerability describes how a person’s health affects their susceptibility to serious harm. It may begin with their underlying health risks, but is also shaped by their circumstances.
Clinical vulnerability is not fixed: risk changes as a person’s health and circumstances change. This page covers the main threats, how risk can be reduced and which groups UK sources say are at greater risk. It is information, not medical advice: if you are worried, speak to your GP, specialist or pharmacist.
Looking for practical help? See useful services, including the Priority Services Register, or join our online support community.
01 · The threats
Vulnerable to what?
Clinical vulnerability is about far more than infection. These are the main threats to people with long-term health conditions, older people, pregnant people and babies where we have found a published source.
Air pollution
The WHO links outdoor air pollution with cardiovascular and respiratory disease and with cancers, and estimated that in 2019 about 68% of related premature deaths were from ischaemic heart disease and stroke, 14% from COPD, 14% from acute lower respiratory infections and 4% from lung cancer.[1]
Read the evidence
It lists asthma and diabetes among the noncommunicable diseases involved,[2] says emerging evidence links air pollution with impaired kidney function, cognitive decline, dementia, depression and anxiety, and names children, young people and pregnant women among the most vulnerable.[3] UK government guidance names older people, children, people with heart or lung disease, pregnant women, people near busy roads and low-income communities as most affected. It links PM2.5 with coronary heart disease, diabetes and COPD and nitrogen dioxide with diabetes and asthma, and points to indoor sources such as appliances burning carbon fuels, household products, tobacco smoke and radon.[4]
Wildfire smoke
Fine particles in smoke can reach deep into the lungs and the bloodstream.
Read the evidence
People with asthma, heart disease or other respiratory conditions can be more seriously affected, potentially needing hospital admission, and children, older adults and pregnant women are also at greater risk. The most effective step is to stay indoors with doors and windows closed. UKHSA says surgical masks are not usually recommended for smoke, while WHO Europe advises a well-fitting FFP2 or N95 mask if you have to go outside. Fire and rescue services in England and Wales responded to nearly 1,000 wildfire incidents in 2025, a record.[5][6]
Heat
UKHSA notes that heat does not have to be extreme to be dangerous: significant heat-associated deaths have been recorded during yellow Heat Health Alerts.[7]
Read the evidence
In summer 2025 it estimated 1,504 heat-associated deaths in England, with the highest rates in people aged 85 and over, followed by those aged 75 to 84. Circulatory disease, cancer, and dementia and Alzheimer’s were the causes with significant heat-associated deaths.[8] Some medicines can raise the risk in hot weather, so speak to your prescriber rather than stopping anything.[9]
Cold
UKHSA estimated 2,544 cold-associated deaths in England in winter 2024 to 2025.
Read the evidence
Older people were most affected, and circulatory disease such as heart disease accounted for the largest number of deaths (834).[10] Of those deaths, 1,095 were linked to cold weather causing increases in ’flu infection.[10] Cold-Health Alerts run from 1st November to 31st March in England and flag when vulnerable people are at particular risk.[11] UKHSA’s list of those at risk includes people with heart and lung conditions, mental health conditions, young children, pregnant women, people on a low income and people sleeping rough.[12]
Power and water cuts
People who rely on electrically powered equipment can be at risk quickly in a power cut.
Read the evidence
The national energy register names ventilators, dialysis and feeding pumps, nebulisers, oxygen concentrators, refrigerated medicines, stair lifts, hoists and electric beds, and Asthma + Lung UK adds CPAP machines. Some people also have a medical need for water, such as dialysis patients.[13][14][15] See emergency planning.
Disruption to medicines and treatment
NHS England says medicine supply problems can significantly affect patients’ care.
Read the evidence
Recent shortages have included treatments for diabetes, epilepsy and ADHD, and most supply problems in 2024 were attributed to manufacturing problems. Where a Serious Shortage Protocol is issued, community pharmacists can supply a specified alternative without going back to the prescriber.[16][17]
Severe allergies
The NHS describes anaphylaxis as a life-threatening allergic reaction that happens very quickly.[68]
Read the evidence
Common triggers include foods such as nuts, cows’ milk, eggs, fish or sesame, medicines such as antibiotics or NSAIDs, wasp and bee stings, anaesthetics and latex. It needs an adrenaline auto-injector and a 999 call straight away.[68] What is in the food, the air and the room can decide whether a shared place is safe, so schools, workplaces and venues need to know who has a serious allergy and plan for it.
Flooding
The Environment Agency estimates that 6.3 million properties in England are in areas at risk of flooding from rivers, the sea or surface water.[49]
Read the evidence
UKHSA says people with chronic conditions can find that floods worsen or speed up the decline in their health, and that flooding may disrupt access to care, essential medicines and services, especially if internet connections and transport routes are cut. It notes that people receiving care at home, such as oxygen, dialysis or palliative care, can face barriers to evacuation, that most of the health burden of flooding in England comes from its effects on mental health, and that generators used inappropriately can cause carbon monoxide poisoning.[48] Its climate and health report adds that stressors such as lack of access to healthcare or prescription medicines can put people at greater risk of the psychological effects of flooding, and recommends planning targeted support for vulnerable people, such as those with a chronic illness.[18]
Conflict and displacement
In conflicts and humanitarian emergencies, damage to health services and disrupted travel can cut people off from treatment they rely on, such as dialysis.
Not exhaustive. If you think an important threat is missing and you know a good source, please tell us.
02 · The big idea
Two kinds of risk, and both matter
A person’s own conditions always carry risk. What is around them can add to it, or take it away.
The person’s health
Conditions, age, pregnancy, treatment: always present
The threat
Infections, allergens, heat, cold, smoke, a power cut
What is around them
Air, heating and cooling, power, support, how things are arranged
The risk
Not one fixed number
From the person’s own health
Many conditions carry higher risk whatever the circumstances: they can cause serious illness, flare up, and need regular treatment, monitoring and medicines.
From what is around them
Air, temperature, power and water, medicines, and how care, work or school are arranged can add to that risk or reduce it. Unsafe settings make people more vulnerable, and settings can be changed.
Managing health and making settings safe go together. Good clinical care does not remove the need for safer places, and safer places do not replace clinical care.
03 · Reducing risk
The hierarchy of controls
The hierarchy of controls is a ranking of ways to deal with a hazard, from the most effective to the least. The best protection is to take the hazard away. The weakest is to rely on each person protecting themselves, every time.
Where the hierarchy comes from
Health and safety professionals use it to decide what to do first. You start at the top, and you only move down a step when the step above cannot do the whole job. The standard version has five levels: elimination, substitution, engineering controls, administrative controls and personal protective equipment. The US National Institute for Occupational Safety and Health and the UK Health and Safety Executive list them in the same order, and the HSE says personal protective equipment should be the last resort.[23][24] Government infection prevention guidance for adult social care says measures should be risk assessed and prioritised in line with the hierarchy of controls.[25] Here is how it looks for the threats on this page, from top to bottom.
Most effective: do this first
Elimination and substitution
Remove the risk
Take the hazard away, or take people away from it.
Read the evidence
Where a hazard can be removed, do that first. The NHS asks people not to visit hospitals or care homes for two days after norovirus symptoms stop.[26] Indoors, it means dealing with the source of pollutants such as appliances burning carbon fuels, tobacco smoke and household products.[4] When a place is hazardous, for example in smoke, flood or a heatwave, it can mean moving an event or an appointment.
Engineering controls
Make the shared place safer
Change the place, so protection does not depend on any one person.
Read the evidence
Ventilation and air cleaning, heating and cooling, and back-up power for essential equipment. Regularly letting fresh air into rooms and shared areas is one of the standard infection control precautions in government guidance,[25] and employers must make sure there is adequate ventilation in enclosed workplaces.[27] In January 2024 UK Power Networks reported a trial of free loaned battery packs for customers who rely on electricity for medical reasons during power cuts of over four hours.[28]
Administrative controls
Change how things are arranged
Plan ahead, adjust, and make sure help reaches the people who need it.
Read the evidence
Reasonable adjustments to how an appointment, job, lesson or activity is arranged, so that a higher-risk person is not shut out or exposed. The legal duty to make them only applies to people covered by the Equality Act’s definition of disability (see above).[22] Also: advance warning and priority help through Priority Services Registers,[15][29] and emergency plans for people who rely on equipment or medicines.[30]
Personal protective equipment (PPE)
Protect the person themselves
Vaccination, treatment and masks sit together at the bottom, because they all depend on the person at risk.
Vaccination and treatment
Government guidance says vaccination remains one of the most important defences against Covid-19 and ’flu, and that Covid-19 treatments are most effective if started early, ideally within 5 days of symptoms.[25][31]
Read the evidence
Neither works equally well for everyone, and some people with weakened immune systems respond less well, which is one reason the layers above matter.
Masks and respirators
Government guidance suggests people with weakened immune systems consider a well-fitting face covering in crowded public spaces, and notes that face coverings are primarily worn to protect others, with only limited protection for the wearer.[31] That is not true of FFP2 and FFP3 respirators.[66][67]
Read the evidence
In care homes, staff and visitors should wear Type IIR surgical masks if the person being cared for has symptoms of a respiratory infection, or would prefer it.[25] If you are visiting someone with a weakened immune system, please read that guidance too: it suggests visitors may be asked to test, keep their distance or wear a face covering, and to ventilate rooms.[31]
Least effective on their own: do not rely on these alone
04 · Practical planning
Power, water and medicines
Power cuts, water interruptions, floods, extreme weather and supply problems hit hardest when people depend on equipment, treatment or medicines.
Why these registers exist
Cabinet Office guidance for emergency planners in England lists regular medication and medical equipment among the needs of people who may be vulnerable in an emergency, and records that gas and electricity suppliers must keep a Priority Services Register and that water companies are required to identify and prioritise vulnerable customers.[30]
Energy: the Priority Services Register
A free register for England, Scotland and Wales; your network operator and your energy supplier each keep their own.[29]
More detail
National Grid lists people who depend on ventilators, dialysis or feeding pumps, nebulisers, oxygen concentrators or refrigerated medicine, people using a stair lift, hoist or electric bed, and people with a temporary need such as hospital recovery.[13] Operators can offer advance notice of planned cuts and priority support in an emergency, such as heating and cooking facilities. Registration does not restore power faster or guarantee a continuous supply.[29] 105 is the free number to call in a power cut.[28]
Water: priority services
Register with your own water company; all water companies in England and Wales have schemes.
More detail
The Consumer Council for Water says the help may be of most use to people with a serious illness or a medical need for water, such as dialysis patients or people taking regular medication. Support includes a password scheme, a nominated contact and an emergency water supply if you have no water and cannot get to a collection point or need it for medical reasons.[15] Kidney Care UK points out that energy and water registers are separate, so register with both, and that Northern Ireland has its own Critical Care Register.[32]
Your own plan and back-up
Aim to keep about two weeks of medicines and essential supplies at home, so a power cut, flood or delivery problem does not leave you short.
More detail
Order repeat prescriptions in good time: most GP practices and pharmacies let you request them before you run out, so check how much notice yours needs. If you rely on equipment such as oxygen, a ventilator, a feeding pump, a nebuliser or home dialysis, ask your care team or supplier what to do if the power fails, and keep their contact details where you can find them quickly.
Eligibility and services differ between companies and nations, so check your own network operator and water company. We have not found a published priority list that is specific to heat or cold.
05 · Infections
Infections
Pneumonia, and infections caught in hospital
Pneumonia is inflammation of the lungs, usually caused by an infection.
Read the evidence
The NHS says babies, older people and people with heart or lung conditions are at risk of getting seriously ill.[34] It can also start in hospital, in people who were admitted for something else. NICE says hospital-acquired pneumonia occurs in around 0.5% to 2% of hospitalisations, is a common cause of illness and death, and adds 7 to 9 days to a hospital stay; pneumonia as a whole accounts for around 29,000 deaths a year in the UK.[35] During the first six months of the pandemic in England, UKHSA researchers estimated that up to 1 in 6 SARS-CoV-2 infections among hospitalised Covid-19 patients could be attributed to transmission in hospital.[36]
Respiratory infections
NHS and UKHSA guidance recognises that people with long-term conditions, older people, pregnant people and very young babies are at higher risk of serious illness from ’flu, and from Covid-19 and RSV.[37][38][39]
Gastrointestinal infections
Norovirus is usually short-lived, but older people, babies and people with weakened immune systems are more at risk of serious dehydration.
Read the evidence
It spreads in hospitals and care homes, which is why the NHS asks people not to visit them for two days after their symptoms stop.[26]
Sepsis
Anyone can develop sepsis, but the NHS lists babies under 12 months, people over 75, people who are pregnant or recently pregnant, and people with weakened immune systems (for example through chemotherapy, HIV, sickle cell disease or immunosuppressant medicines) as being at higher risk.[42]
The same person can be at modest risk in a well-ventilated room and at much higher risk in a packed, stuffy waiting room.
With infection, the place decides how much of the threat reaches the person, on top of the risk their own conditions always carry.
Why the place matters
Waiting rooms and wards bring together people who are unwell, including those who are infectious, and people who are already at higher risk. Care homes, schools, workplaces, public transport and busy winter months raise similar questions: how many people, how much shared air, and what protections are in place. The hierarchy of controls above applies directly: remove the infection where you can, then clean the air, then adjust arrangements, and only then rely on vaccination and masks.
Who is at high risk from coronavirus (Covid-19) and other infections in the UK?
Clinically Vulnerable people are more vulnerable to infections. An illness that is mild for most people can make them seriously ill, and the risk comes from their own health as well as from the place they are in. It isn’t only Covid-19: many of the same people are at higher risk from ’flu, RSV, pneumonia and measles, as well as the infections above.[37][38][39][40]
For Covid-19, people at higher risk include people with a weakened immune system, older people (age is one of the biggest risk factors) and people with certain long-term conditions.[31][43] The NHS offers the highest-risk groups extra protection: a vaccine each autumn for adults aged 75 and over, people living in care homes for older adults and anyone aged 6 months to 74 with a weakened immune system, and antiviral treatment for people at highest risk who test positive.[43][57][58]
Not being on these lists doesn’t mean someone is safe. Many more people were offered a Covid-19 vaccine in earlier programmes because of their health, including people with heart, kidney or liver disease or diabetes. Most of them are no longer offered one unless they are 75 or over or have a weakened immune system.[43] They are still offered a ’flu vaccine every autumn, because the NHS counts their long-term condition as a clinical risk group for ’flu.[37][38] Not being offered a vaccine is not the same as not being at risk.
Who is offered vaccines and treatments
The lists below show who the NHS offers vaccines and treatments to for each infection, and who else is at higher risk. The official phrase “highest risk” is used here. These lists decide who is offered something. They are not a statement that only those people are at risk.
Covid-19
Vaccine (autumn 2026)
Treatment
- Antiviral tablets or capsules (nirmatrelvir with ritonavir, known as Paxlovid, or molnupiravir) for people aged 12 and over at highest risk who test positive and have symptoms.[58]
- Treatments work best if started early, ideally within 5 days of symptoms.[31]
- People at highest risk include some people with Down’s syndrome, certain cancers or blood conditions, sickle cell disease, chronic kidney disease stage 4 or 5, severe liver disease, an organ transplant, some autoimmune conditions, HIV with a weakened immune system, some brain or nerve conditions (such as motor neurone disease, Parkinson’s or some types of dementia) and certain lung conditions.[31][58]
Higher risk of serious illness
- People with a weakened immune system.[31][43]
- Older people: age is one of the key risk factors.[43]
- People who were offered a Covid-19 vaccine in earlier programmes because of their health, such as heart, kidney or liver disease, or diabetes. Most are no longer offered one.[43]
- People offered a ’flu vaccine because of a long-term condition.[37][38]
’Flu
Vaccine (every autumn)
- Adults aged 65 and over, people living in a care home, and pregnant women at any stage of pregnancy.[37]
- People aged 18 to 64 with certain long-term conditions: lung conditions (asthma only if it needs steroid inhalers or tablets), heart conditions, chronic kidney disease, liver disease, some brain or nerve conditions, a learning disability, diabetes, a weakened immune system, spleen problems, or a BMI of 40 or above.[37][38]
- Children aged 2 to 3, school-aged children (reception to year 11), and children aged 6 months to 17 with certain long-term conditions.[56]
- Main carers of an older or disabled person, people who live with someone with a weakened immune system, and people aged 16 and over who are sleeping rough or in a homeless hostel or night shelter.[37]
Treatment
- Antiviral medicine (oseltamivir or zanamivir) for people in at-risk groups when ’flu is circulating: long-term lung, heart, kidney, liver or neurological conditions, diabetes, a weakened immune system, and people aged 65 and over.[59]
- Antivirals are also recommended in pregnancy. They work best if started within 48 hours of symptoms.[60]
- People in at-risk groups may also be offered antivirals after close contact with ’flu at home or in a care home.[60]
Higher risk of serious illness
- Older people, babies under 6 months, pregnant women, and people in the clinical risk groups above.[38]
RSV
Vaccine
Treatment
Higher risk of serious illness
- Babies under 6 months, young children born prematurely, adults over 75, and people with a weakened immune system or a long-term lung or heart condition.[39]
Pneumonia
Vaccine (pneumococcal)
- Babies (at 16 weeks and 1 year), and adults aged 65 and over.[62]
- Children and adults in clinical risk groups: spleen problems (including sickle cell disease), chronic lung disease (asthma only if severe enough to need frequent steroid tablets), chronic heart disease, chronic kidney disease stage 4 or 5 (including dialysis or a transplant), chronic liver disease, diabetes needing medicine, a weakened immune system, cochlear implants and cerebrospinal fluid leaks.[62][63]
Treatment
- Antibiotics if the cause is bacterial. In hospital, treatment may also include steroids and oxygen.[34]
Higher risk of serious illness
- Babies and young children, people over 65, and people with cardiovascular disease or a long-term lung condition.[34]
Measles
Vaccine
- The MMRV vaccine is offered to all young children. The MMR vaccine is for older children and adults who were not vaccinated when younger.[40]
After contact with measles
06 · Where the terms came from
The UK terms
“Clinically Vulnerable” and “Clinically Extremely Vulnerable” are government terms from the start of the Covid-19 pandemic in 2020.
Read more
“Clinically Extremely Vulnerable” was a list drawn up by government. The protections that came with it, such as shielding advice and the National Shielding Service, were allocated by government and then withdrawn: paused from 1st August 2020 and ended by a letter dated 17th September 2021.[44][45] The NHS first identified around 1.3 million people, and the list later grew to about 2.2 million in England.[46]
Today the phrase in official guidance is usually “highest risk” or “severely immunosuppressed”, tied to eligibility for vaccines and antivirals.[43] Those details are in the infections section above.
07 · Groups and situations
Who is at greater risk from what?
This table brings together what published sources say. If you are worried about your own health, speak to your GP, specialist or pharmacist.
By group
| Group | ’Flu vaccine offered | Air pollution and smoke | Heat | Cold | Flooding | Severe allergies | Priority services (power and water) |
|---|---|---|---|---|---|---|---|
| Weakened immune system | Yes[37][38] | – | Yes (some treatments)[9] | Yes[50][54] | Yes[48][54] | – | Yes (if long-term)[51] |
| Lung conditions | Yes (all except mild asthma)[37][38] | Yes[4][5][41] | Yes[9][41] | Yes[12][41] | Yes[48] | Yes (asthma, especially if poorly controlled)[69][70] | Yes[13][51] |
| Heart, kidney or liver disease, diabetes | Yes[37][38] | Yes[1][4][5][52] | Yes[8][9][53] | Yes[10][12] | Yes[48] | Yes (heart disease and some heart medicines)[69][70] | Yes[13][15][51] |
| Neurological conditions, dementia, learning disability | Yes (some neurological conditions)[37][38] | – | Yes (dementia, Parkinson’s)[8][9] | Yes (learning disability, dementia)[10][12] | Yes[18][48] | – | Yes[13][15][51] |
| Mental health conditions | – | – | Yes[9][50] | Yes[12][50] | Yes[48] | – | Yes[13][15][51] |
| Severe obesity | Yes[37][38] | Yes[47] | Yes[65] | – | Yes[48] | – | – |
| Older people (65+) | Yes[37] | Yes[4][5] | Yes[8][9] | Yes[10][12] | Yes[48] | Yes (reactions to medicines)[69] | Yes (state pension age)[13][51] |
| Pregnancy | Yes[37][38] | Yes[4][5] | Yes[9][50] | Yes[12][50] | Yes[48] | – | Yes[51] |
| Babies and young children | Yes (from age 2; from 6 months with some conditions)[56] | Yes[1][4][5] | Yes[9] | Yes[12] | Yes[48] | Yes (food reactions most common)[69] | Yes[51] |
| Low income or homelessness | Yes (sleeping rough or in a hostel)[37] | Yes (low income)[4][47] | Yes (homelessness)[9] | Yes[12][50] | Yes (low income)[48] | – | – |
| Medical equipment or treatment at home | – | – | Yes (some medicines)[9] | – | Yes[48] | – | Yes[13][15][51] |
How to read the table
✓ means a published source identifies that group as at greater risk from that threat. In the ’flu vaccine column, it means the group is offered a free NHS ’flu vaccine, and in the priority services column, that the group can join priority services. Words in brackets add an important detail. Numbers link to the sources at the foot of the page. In the risk columns, a dash means we have not found a published source, not that there is no risk. In the ’flu vaccine and priority services columns, a dash means the group is not named in the eligibility lists. Teenagers and young adults, who are not a group in this table, are at highest risk of fatal reactions to food.[69]
08 · A caution about labels
Why labels only tell part of the story
Categories help decide who is offered a vaccine, a treatment or extra help. They cannot describe anyone’s whole life.
Someone outside a category can still be at real risk, and someone inside one is not at the same risk all the time. Risk is not one number:
It depends on the threat
Someone can be at high risk from heat or a power cut and at ordinary risk from a stomach bug, or the other way round.
It changes over time
During chemotherapy, in the months after a transplant, in late pregnancy, when a condition flares up, or in a heatwave or a cold snap.
It depends on the protection around you
Vaccination, access to treatment, clean air, a safe temperature, working power and water, and how care and everyday activities are arranged.
Even official lists are written for a particular purpose.
Examples from official lists
The ’flu vaccine eligibility list, for example, is a practical list of conditions and circumstances rather than a statement that only those people are at risk.[37] UKHSA’s hot-weather guidance says an individual’s risk relates to a combination of factors in their health, behaviours and environment,[9] and its cold-weather list includes circumstances such as low income and sleeping rough alongside health conditions.[12]
Share your experience
Does this match your life?
If you or your family live with higher risk, your experience helps us show what safe and unsafe settings look like in practice. Tell us what has helped and what has got in the way.
Verify
References
Every claim above links to a numbered source. Select a number in the text to open the list at that source.
Show all 66 referencesHide references
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- Health consequences of air pollution. World Health Organization, 25th June 2024. https://www.who.int/news/item/25-06-2024-what-are-health-consequences-of-air-pollution-on-populations
- Air pollution: tackling a critical driver of the global NCD crisis. World Health Organization commentary, July 2025. https://www.who.int/news-room/commentaries/detail/air-pollution–tackling-a-critical-driver-of-the-global-ncd-crisis
- Health matters: air pollution. Public Health England, published 2018. https://www.gov.uk/government/publications/health-matters-air-pollution/health-matters-air-pollution
- Why severe wildfires are becoming more frequent in the UK and how to cope with the health risks. UKHSA blog, 2026. https://ukhsa.blog.gov.uk/2026/07/14/why-severe-wildfires-are-becoming-more-frequent-in-the-uk-and-how-to-cope-with-the-health-risks/
- Wildfire smoke: a frequently underestimated health risk. WHO Europe, 2026. https://www.who.int/europe/news/item/31-07-2026-wildfire-smoke–a-frequently-underestimated-health-risk
- How to keep cool and stay well during hot weather. UKHSA blog, 2026. https://ukhsa.blog.gov.uk/2026/06/23/how-to-keep-cool-and-stay-well-during-hot-weather/
- Heat mortality monitoring report, England: 2025. UK Health Security Agency, 2026. https://www.gov.uk/government/statistics/heat-mortality-monitoring-report-england-2025/heat-mortality-monitoring-report-england-2025
- Supporting vulnerable people before and during hot weather: healthcare professionals. UK Health Security Agency, published 19th December 2024. https://www.gov.uk/guidance/supporting-vulnerable-people-before-and-during-hot-weather-healthcare-professionals
- Cold mortality monitoring report, England: winter 2024 to 2025. UK Health Security Agency, 2026. https://www.gov.uk/government/statistics/cold-mortality-monitoring-report-england-winter-2024-to-2025/cold-mortality-monitoring-report-winter-2024-to-2025
- Cold-Health Alerts. Met Office. https://weather.metoffice.gov.uk/warnings-and-advice/seasonal-advice/cold-weather-alerts
- Supporting vulnerable people before and during cold weather: for healthcare professionals. UK Health Security Agency. https://www.gov.uk/guidance/supporting-vulnerable-people-before-and-during-cold-weather-for-healthcare-professionals
- Who can join the Priority Services Register. National Grid. https://customer.nationalgrid.co.uk/advice-and-guidance/priority-services/priority-services-faqs/who-can-join-the-priority-services-register
- Breathing easier during power cuts: the importance of Priority Services. Asthma + Lung UK, 2026. https://www.asthmaandlung.org.uk/blog/advice-support/breathing-easier-during-power-cuts-importance-priority-services
- Extra free help: priority services. Consumer Council for Water, updated 2026. https://www.ccw.org.uk/advice-and-support/households/priority-services/
- A guide to the systems and processes for managing medicines supply issues in England. NHS England. https://www.england.nhs.uk/long-read/a-guide-to-the-systems-and-processes-for-managing-medicines-supply-issues-in-england/
- Medicines shortages (CBP-9997). House of Commons Library, 2026. https://commonslibrary.parliament.uk/research-briefings/cbp-9997/
- Health effects of climate change (HECC) in the UK 2023, chapter 3: flooding. UKHSA / DHSC. https://assets.publishing.service.gov.uk/media/657086ad746930000d488919/HECC-report-2023-chapter-3-flooding.pdf
- Stopping attacks on health care. World Health Organization. https://www.who.int/activities/stopping-attacks-on-health-care
- Health Care in Danger. International Committee of the Red Cross. https://healthcareindanger.org/
- Noncommunicable diseases in emergencies. World Health Organization. https://www.who.int/publications/i/item/noncommunicable-diseases-in-emergencies
- Definition of disability under the Equality Act 2010. GOV.UK. https://www.gov.uk/definition-of-disability-under-equality-act-2010
- Hierarchy of Controls. National Institute for Occupational Safety and Health (NIOSH), CDC, 2024. https://www.cdc.gov/niosh/hierarchy-of-controls/about/index.html
- Using personal protective equipment (PPE) to control risks at work: managing risk using PPE (hierarchy of controls). Health and Safety Executive. https://www.hse.gov.uk/ppe/managing-risk-using-ppe.htm
- Infection prevention and control (IPC) in adult social care: acute respiratory infection (ARI). Government guidance (England), updated 2024. https://www.gov.uk/government/publications/infection-prevention-and-control-in-adult-social-care-acute-respiratory-infection/infection-prevention-and-control-ipc-in-adult-social-care-acute-respiratory-infection-ari
- Norovirus. NHS, 2026. https://www.nhs.uk/conditions/norovirus/
- Ventilation in the workplace. Health and Safety Executive. https://www.hse.gov.uk/ventilation/
- Extra support for people reliant on electricity for medical reasons. UK Power Networks, 2024. https://www.ukpowernetworks.co.uk/news/extra-support-for-people-reliant-on-electricity-for-medical-reasons
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