For most people, Covid-19 is a brief and mild disease but some are left struggling with symptoms including lasting fatigue, persistent pain and breathlessness for months.
The condition known as “long Covid” is having a debilitating effect on people’s lives, and stories of being left exhausted after even a short walk are now common.
So far, the focus has been on saving lives during the pandemic, but there is now a growing recognition that people are facing long-term consequences of a Covid infection.
Yet even basic questions – such as why people get long Covid or whether everyone will fully recover – are riddled with uncertainty.
What is long Covid?
There is no medical definition or list of symptoms shared by all patients – two people with long Covid can have very different experiences.
However, the most common feature is crippling fatigue.
Others symptoms include: breathlessness, a cough that won’t go away, joint pain, muscle aches, hearing and eyesight problems, headaches, loss of smell and taste as well as damage to the heart, lungs, kidneys and gut.
Mental health problems have been reported including depression, anxiety and struggling to think clearly.
It can utterly destroy people’s quality of life. “My fatigue was like nothing I’ve experienced before,” said one sufferer Jade Gray-Christie,
Long Covid is not just people taking time to recover from a stay in intensive care. Even people with relatively mild infections can be left with lasting and severe health problems.
“We’ve got no doubt long Covid exists,” Prof David Strain, from the University of Exeter, who is already seeing long-Covid patients at his Chronic Fatigue Syndrome clinic, told the BBC.
How many people are getting it?
A study of 143 people in Rome’s biggest hospital, published in the Journal of the American Medical Association, followed hospital patients after they were discharged.
It showed 87% had at least one symptom nearly two months later and more than half still had fatigue.
However, such studies focus only on the minority of people who end up needing hospital treatment.
The Covid Symptom Tracker App – used by around 4 million people in the UK – found 12% of people still had symptoms after 30 days. Its latest, unpublished data, suggests as many as one in 50 (2%) of all people infected have long-Covid symptoms after 90 days.
Do you need severe Covid to get long Covid?
It appears not.
Half of people in a study in Dublin still had fatigue 10 weeks after being infected with coronavirus. A third were physically unable to return to work.
Crucially, doctors found no link between the severity of the infection and fatigue.
However, extreme exhaustion is only one symptom of long Covid.
Prof Chris Brightling, from the University of…