Six weeks after contracting Covid-19 in April, Dr Amy Small felt well enough to attempt a walk around Holyrood park in Edinburgh with her young family. Her kids wanted to climb Arthur’s Seat – the craggy hill at its centre. Thinking it would be OK if she walked slowly, Small agreed. “It put me in bed for several days afterwards,” she said.
In June, she returned to work as a GP, for a single half day: “It floored me completely for 10 days and took two months to get back to where I was prior to that,” she said. “I couldn’t speak one day due to the fatigue and struggled to stay hydrated as I didn’t have the energy to eat or drink.”
Before Covid, Small ran 5km at least three times a week. Now, even opening her eyes is a strain some days.
Based on current estimates, about 10% of Covid-19 patients develop lasting symptoms, one of the most common being fatigue. The underlying mechanism is still unclear, but possible explanations include reduced oxygen supply to tissues caused by heart or lung damage, or muscle weakness from prolonged bed rest.
However, some doctors are increasingly concerned about the overlap between long Covid and another largely virus-triggered illness: “It’s extraordinary how many people have a postviral syndrome that’s very strikingly similar to myalgic encephalomyelitis/chronic fatigue syndrome,” said the US’s top public health official, Dr Anthony Fauci, in July. “They just don’t get back to normal energy or normal feeling of good health.”
Like people with ME/CFS, many long-Covid patients report headaches, brain fog, sleep problems, a racing heart, joint and muscle pain and fatigue. Some also experience a relapse of fever, muscle pain and exhaustion, known as “post-exertional malaise”, if they exercise beyond their capabilities.
“There are so many similarities between long Covid and ME/CFS it leads me to believe the underlying pathology is probably the same – except that long Covid is presenting as an epidemic, whereas ME/CFS has presented in a very sporadic way, and by no means in such large numbers in such a short space of time,” said Dr William Weir, a consultant in infectious diseases with a special interest in ME.
Another thing the conditions have in common is medical disagreement over how best to treat the fatigue they cause. Last week, the National Institute for Health and Care Excellence (NICE) dropped a longstanding recommendation that patients with ME/CFS be prescribed graded exercise therapy (GET), which involves incremental increases in physical activity to gradually build up tolerance. Patient advocates have long argued that GET can cause lasting damage to people’s health.
The new draft guidelines don’t cover Covid-related fatigue. This may be covered by separate “long Covid” guidelines that are expected next month. Yet patient advocates are concerned that GET might result in similar harm for people with long Covid.
“Although NICE has already issued a statement that GET may not be appropriate for people with post Covid illness, we are concerned that several of the new NHS England clinics for Covid rehabilitation are recommending graded exercise or its equivalent to patients,” said Sian Leary of the patient advocacy group #MEAction.
“I have certainly seen plenty of posts from patients in long-Covid forums where doctors have told them to ‘just push yourself a bit more’,” said Small. This doesn’t surprise her. “During GP training we were told that GET was what one would suggest to someone who was recovering from a postviral illness like ME – so I suppose when GPs see someone who is experiencing ongoing symptoms of Covid this is what many of them would turn to. It is going to take time for those new CFS/ME guidelines to filter down.”
Olivia Hoare is an occupational therapist who fell ill with suspected Covid-19 in May, and still has severe fatigue. On a “crash” day, she struggles to sit up in bed for long enough to drink a cup of tea. “I have spoken to several GPs who were sympathetic and listened,” she said. “However, they asked me to ‘up my aerobic exercise’. I was told by one GP to try a 15-minute walk and then a 10-minute run the following week.” Having a close family member with ME, she ignored these suggestions: “My worry is that people will take on board this medical advice and cause [themselves] more harm,” she said.
The NHS website Your Covid Recovery instructs people suffering with Covid-related fatigue to keep active because it “helps to maintain energy levels”. A spokesperson said the website would be updated to reflect upcoming NICE long-Covid guidance if necessary. For now, the website suggests people start by walking for five minutes without stopping, gradually building this up by one or two minutes each day. “You may notice your tiredness increase and some breathlessness at first but these should improve the stronger you get; this is a normal response to doing more exercise for all of us,” it says.
“Although this sounds mild, by telling people to carry on even if their tiredness increases is dangerous to those suffering post-exertional malaise,” said Helen McDade, a volunteer at #MEAction.
Even so, many medical professionals insist gentle, graded exercise is a crucial part of Covid-19 recovery.
Fatigue isn’t only associated with ME/CFS, but with many inflammatory illnesses. “Time will tell if the fatigue of long Covid is akin to the fatigue of CFS, or more akin to the fatigue of multiple sclerosis or rheumatoid arthritis,” said Elizabeth Murray, a professor of e-health and primary care at University College London. “People with long Covid also have other problems, and there’s no doubt that gentle exercise does help with breathlessness and depression. If you haven’t used your muscles for two weeks because you’ve been too unwell, they will have deconditioned.”
By graded exercise, she means starting very gently and gradually building up. She is behind a Covid rehabilitation app being used by patients discharged from Barts hospital in London who are still experiencing symptoms. Graded exercises that gradually build in intensity are part of the treatment.
The British Society of Rehabilitation Medicine also lists exercise as a key component of Covid-rehabilitation: “Exercise is likely to be needed by all patients, to overcome deconditioning, improve [lung] function and any neuromuscular complications,” a recent report said.
“It is crucial to acknowledge that not all long-Covid patients will behave like CFS,” said Dr Manoj Sivan, an associate clinical professor and consultant in rehabilitation medicine at the University of Leeds, who runs a long-Covid clinic in the city. He also sits on the BSRM’s executive committee. “Fatigue is multifactorial, and there are some patients with deconditioning and weakness who might benefit from GET,” he said.
However, he added that GET could be counterproductive in those patients presenting with a “boom and bust” pattern of symptoms consistent with postviral fatigue. Individualised patient assessment is therefore essential. “We know long Covid has different patterns of presentation and future research will look into targeting specific rehabilitation approaches to specific subgroups,” he said.
Until this happens, ME/CFS patient advocates are urging people with long Covid to learn from their experiences of dealing with postviral fatigue, stressing the importance of “pacing”. This means listening to your body and balancing physical and mental activity with rest, rather than pushing yourself to boost stamina. “It doesn’t mean you don’t do anything, but if you feel you need to rest, you should stop what you are doing and rest,” said Small, who credits the approach with her ongoing recovery. Earlier this month, she returned to work and managed a half day of patient consultations. “It did take me twice as long as it used to, but I made sure I stopped for a cup of tea,” she said. “It felt great.”