What is Long Covid
If you or a loved one has just received a Long Covid diagnosis — or suspects that recent symptoms might be Long Covid — you probably have a lot of questions. This page is a gentle starting point.
Long Covid is the patient-coined term for symptoms that continue for weeks or months after a COVID-19 infection. It is recognised in UK clinical guidance under NICE NG188. In medical literature it is sometimes called post-Covid-19 syndrome or post-acute sequelae of SARS-CoV-2 (PASC), but Long Covid is the term most people use, and the one this site defaults to.
It is not one illness
Long Covid is better thought of as a family of related problems than a single illness. For one person it may primarily involve fatigue and post-exertional malaise (PEM). For another, the main issue is breathlessness or heart palpitations. For someone else, cognitive difficulties or persistent gut problems dominate.
This is one of the things that makes Long Covid difficult to diagnose, difficult to treat, and difficult to explain to people who have not experienced it.
The defining feature What makes Long Covid Long Covid is the persistence of symptoms after a COVID-19 infection — typically beyond 12 weeks, and often for months or years. The specific symptoms vary significantly from person to person.
How does it start?
Long Covid develops after a COVID-19 infection. That is the one common starting point.
The severity of the initial infection does not reliably predict who develops Long Covid. People who had mild or even asymptomatic COVID-19 can go on to develop long-lasting symptoms. People who were hospitalised with severe acute illness sometimes recover fully, and sometimes do not.
Symptoms can appear in three broad patterns:
- As a continuation of acute COVID-19 that never fully resolved
- After a period of apparent recovery, with new symptoms emerging days or weeks later
- Gradually, with small problems accumulating into something more significant over time
Who gets it?
Long Covid affects people of all ages and backgrounds. It occurs in people who were previously healthy, in children and teenagers, in older adults, and in those with and without pre-existing conditions.
Research suggests some patterns:
- Women appear to be more commonly affected than men.
- Pre-existing chronic conditions are associated with a higher risk.
- Certain initial symptoms — including breathlessness and loss of smell — are associated with a higher likelihood of developing Long Covid.
These are patterns across populations, not predictors at the individual level. Long Covid affects many people who fit none of them.
Is it the same as ME/CFS?
Not quite — but the two overlap significantly. A significant proportion of people with Long Covid meet the diagnostic criteria for ME/CFS. Where that is the case, ME/CFS management approaches — particularly pacing and attention to post-exertional malaise — generally apply.
The main distinguishing features:
- ME/CFS is defined by PEM. Long Covid may or may not involve it.
- ME/CFS can be triggered by many infections, not only COVID-19. Long Covid, by definition, follows COVID-19.
- Long Covid often involves a wider range of body systems than ME/CFS.
For more, see our ME/CFS hub.