Covid-19 has left many patients with debilitating, varied symptoms months after the initial infection has cleared, raising fears about the long-term health costs of the pandemic.
Patients infected in the first wave of the virus have continued to suffer disorders in the brain, lungs, heart, gut, liver, skin and other parts of the body, according to a new review of the disease conducted by the UK National Institute for Health Research.
Some of the symptoms of Long Covid, as the condition is often known, can be seriously debilitating, like “brain fog” and extreme exhaustion. Other consequences are milder, such as hair loss and the inability to taste or smell.
“A common theme is that symptoms arise in one physiological system then abate, only for symptoms to arise in a different system,” the NIHR report said. The review aims to increase awareness of the condition among health workers, while stimulating further research since so little is known today about the prevalence or the causes of Long Covid.
A study in Italy found that 87 per cent of people discharged from a Rome hospital were still experiencing at least one symptom two months after the onset of Covid-19. At least 55 per cent had three or more symptoms including fatigue, breathing difficulties and pain in joints and chest.
Public Health England said last month that around 10 per cent of ‘mild’ Covid-19 cases who were not admitted to hospital reported symptoms lasting more than four weeks. A separate study by King’s College London, using data from its Covid Symptom Study app with 4m regular contributors, suggested that between 10 per cent and 20 per cent of infections led to complications lasting longer than a month.
If around 10 per cent of people with confirmed Covid-19 will suffer from Long Covid, that would mean more than 3.8m people worldwide and more than 65,000 patients in the UK. But the NIHR researchers said it was too soon to give a reliable estimate of prevalence.
“The overwhelming message is that this is not a linear condition,” said Elaine Maxwell, lead author of the NIHR report. “Many [patients] suffer a rollercoaster of symptoms moving around the body, from which they do not recover.”
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There are some parallels between Covid-19 today and the start of the Aids epidemic in the 1980s, according to Philip Pearson, a respiratory physician at Northampton General Hospital and a member of the NIHR study group. “As we understood HIV infection better, we found out about all the different possible presentations of disease.” he said. “Right now, as we try to define our terms, this feels like HIV research was then.”
Long Covid’s wide and fluctuating range of symptoms suggested that it was the result of several overlapping but different syndromes, including postviral fatigue and permanent organ damage, the NIHR report said.
“It feels as if this coronavirus is behaving quite differently to other viral infections like flu,” Dr Pearson added
Despite all the uncertainties, the NIHR authors called for a working definition of Long Covid to be agreed as soon as possible. “The absence of a definition may impact the ability of patients to have their symptoms and experiences properly recognised and treated by healthcare services, which can in turn have a further psychological impact, especially for non-hospitalised patients who were never formally diagnosed.”
In reaction to growing concerns about Long Covid, the UK’s NHS last week committed £10m to set up a regional network of Long Covid clinics to assess patients’ physical, cognitive and psychological condition and, if appropriate, refer them for specialist treatment.
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