The COVID-19 pandemic has had a major impact on health and health inequalities in the UK. Despite rapid global efforts to genetically code the virus and the monumental achievement to develop and deploy effective vaccines, there are aspects of the underlying disease that remain poorly understood. One such concern is the persistent nature of the symptoms that some people experience. In the UK, an estimated 1.1 million (1.69% of the total population) reported symptoms persisting more than four weeks after the first suspected infection – that's 1 in 5 people who tested positive for COVID-19).
There is much more to learn about how COVID-19 affects people and what the implications are for the nation's long-term health. Against this uncertainty, the Health Foundation’s COVID-19 impact inquiry team has reviewed emerging evidence on long COVID. Here we summarise our findings to date.
What is long COVID?
Long COVID (previously known as post-COVID-19 syndrome) is a catch-all term for the experience of symptoms that last weeks or months after the initial viral infection. Studies to date show common symptoms include fatigue, breathlessness and (in more severe cases) organ failure, such as that of the heart and lungs. An evidence review by the National Institute for Health Research (NIHR) suggests clusters of symptoms of four types:
fluctuating multi-system symptoms
lasting organ damage
post-intensive care symptoms (cognitive impairment, declines in mental health, chronic pain, fatigue and shortness of breath).
The COVID Symptoms Study App recorded the prevalence of these symptoms among 4,182 adults who had tested positive for COVID-19 and were regular app-users. The most common symptoms were fatigue and headaches, which were reported by 97.7% and 91.2% (respectively) of people who had experienced symptoms for over 28 days. Other common symptoms included loss of smell (72%) and shortness of breath (75.7%). Different studies have found that cough, muscle aches and mild organ impairments are also prevalent in people experiencing long COVID. Long COVID can also impact children, with the most commonly reported symptoms being tiredness and weakness, fatigue, headache, tummy pain or cramps, and muscle aches and pains.
Does hospitalisation affect long COVID?
Evidence is emerging that the impact of long COVID may be different and more severe for people who have been admitted to hospital or intensive care. A study with 47,780 discharged following COVID-19 found that almost a third were re-admitted and a similar proportion were diagnosed with a respiratory disease. Studies published by the Lancet and the BMJ found that once discharged, patients experienced increased levels of psychological distress and a clinically significant drop in a composite measure of health that captured mobility, self-care, usual activities, pain and psychological symptoms. They were also more likely to suffer severe organ damage, impairment of mental processes (such as problem solving) and were more likely to report anxiety and depression. Early evidence suggests that these patients are at greater risk of death (7.7 times greater than matched controls).
How long does long COVID last?
An NIHR review concluded that the precise duration of long COVID is not known and that many people may suffer for longer than 6 months. In the most recent ONS estimates for the UK, 697,000 experienced long COVID for at least 12 weeks and of those 473,000 for over six months, and 70,000 for over one year. An international web-based survey of 3,762 adults with COVID-19 found that 9 out of 10 people who experience symptoms for at least 4 weeks will suffer effects for more than 35 weeks. An international survey with 510 children found that symptoms lasted for over 8 months on average. While some uncertainty over longevity remains, emerging evidence suggests a significant long-term burden among those experiencing prolonged symptoms.
Can long COVID be treated?
Although there is no specific treatment for long COVID, there are positive signs that people are able to manage their symptoms by drawing on a range of sources such as online help, peer support, complementary therapies and formal health care. People have also recently reported that the COVID-19 vaccine has alleviated long COVID symptoms, although there is limited evidence of this as yet.
The NHS officially launched a long COVID service to support recovery in October 2020. This includes guidance and advice on the self-management of long COVID as well as a designated long COVID clinical service. Although the service is struggling to meet demand and not everyone is yet able to access it, this designated care pathway is a crucial step towards enabling patients to better manage long COVID.
Does long COVID affect everyone equally?
The impacts of long COVID differ by age, gender and pre-existing health status.
Firstly, younger age groups (people younger than 70) are more commonly and more adversely affected. For example, the Office for National Statistics (ONS) estimated that the prevalence of symptoms 5 weeks after testing positive for COVID-19 was highest among 35–49 year olds (at 25.6%) and 50–69 year olds (25.1%), compared to 21% across the general population. In a study with hospitalised individuals, when compared to matched controls, people younger than 70 had higher rates of re-admission, diabetes, chronic kidney disease, respiratory disease, a major adverse cardiovascular event and death than people above 70.
Secondly, long COVID affects women more than men (23% females report symptoms at 5 weeks compared to 18.7% males, and 14.7% as compared to 12.7% 12 weeks later). Women more commonly suffer from moderate to severe fatigue, moderate to severe breathlessness and among those hospitalised more commonly reported experiencing post-traumatic stress disorder (PTSD).
Thirdly, there is a clear social gradient in the experience of long COVID with the prevalence being higher (2.16% of the total population) in the most deprived areas compared to that in the least deprived areas (1.41%).
Fourthly, those working in health and social care had a higher prevalence of long COVID as compared to other sectors.
Finally, long COVID also appears more prevalent among people with pre-existing health conditions. Obesity has been linked to higher rates of moderate and severe breathlessness, PTSD and symptoms related to communication, for example. Obesity and co-morbidity are associated with severity of symptoms. Individuals with asthma are also more likely to experience long COVID. The prevalence is also higher in those whose activity was limited a lot by health conditions.
The evidence on differences by ethnicity is inconclusive, and we will be reviewing emerging evidence to expand our understanding.
What is the wider impact of long COVID for individuals?
In addition to the physical and mental implications outlined above, long COVID also carries social consequences for individuals and their families. Although our understanding of these wider effects is limited, there is evidence to suggest they could be significant. Qualitative studies report a heavy sense of loss, guilt and stigma among some sufferers. Long COVID can also affect many aspects of day-to-day life, such as the ability to work or caring responsibilities. As of 6 March 2021, 674,000 people in the UK reported that long COVID was adversely affecting their day-to-day activities, and 196,000 reported that their ability to undertake these activities had been limited a lot.
Parents of children with an average age of 10 years report wide-ranging impacts. It is particularly concerning that only 10% of children reported returning to previous levels of physical activity, with over 4 in 5 reporting a change in energy levels. A change in mood, sleep and appetite was seen in about half the children.
Those who have been hospitalised with COVID-19 and subsequently suffer long COVID are reported to have had to take 4–10 weeks of sick leave from work after being discharged from hospital. The PHOSP-COVID study found that of those who were working before COVID-19, 17.8% were no longer working, and 19.3% experienced a health-related change in their occupational status. Approximately half of these had required the most intensive clinical treatment for COVID-19. People with co-morbidities or obesity were more likely to be no longer working or experienced a change in their occupational status. Such consequences have led to growing concerns about the effect of long COVID on employers’ sickness and absence policies – there have been calls to recognise it as an occupational disease. Health Foundation analysis (of self-reported long COVID, from the Understanding Society survey) suggests that those with long COVID have reduced employment rates compared to the same group pre-pandemic, and also compared to those who reported an infection without persistent symptoms.
It is imperative that we continue to deepen our understanding of long COVID and its wider impacts on individuals and society. Only by doing so will we be able to fully realise the unequal susceptibility to and diverse effects of long COVID, and its long-term implications for the nation’s health.
Data collection and research will provide further insight. Ongoing studies include the long COVID symptom study by the ONS, the post-hospitalisation COVID-19 study, a systematic review by the International Severe Acute Respiratory and emerging Infection Consortium (ISARIC), and further research projects funded by the National Institute for Health Research (NIHR) and UK Research and Innovation (UKRI).
There is still much to learn about COVID-19 and its long-term health impacts – and the wider implications for different groups in society. As we continue to emerge from lockdown, research into long COVID, and care and treatment for the disease must remain a focus.
Shreya Sonthalia is a Research Fellow in the COVID-19 impact inquiry team at the Health Foundation .
Mehrunisha Suleman is a Senior Research Fellow in the COVID-19 impact inquiry team at the Health Foundation .
Adam Tinson, Senior Analyst, Healthy Lives team at the Health Foundation.
David Finch, Senior Fellow, Healthy Lives team at the Health Foundation.
- LongCovidSOS (a support and campaign group for people with long COVID)
- Lingering and painful: the long and unclear road to coronavirus recovery (personal accounts in the Guardian from individuals experiencing long COVID)
- The lasting misery of coronavirus long-haulers (Nature article)
- A long-term plan for long COVID (paper from the Tony Blair Institute for Global Change)