“Long-Covid,” the lingering impact of the coronavirus infection that can sometimes lurk for months, appears to be affecting people in at least four different ways.

Using data and testimonies of people who are experiencing long-Covid, a new report by the British National Institute for Health Research (NIHR) proposes that long-Covid may not be one syndrome but possibly up to four different syndromes:

• permanent organ damage
• post-intensive-care syndrome
• post-viral fatigue syndrome
• continuing Covid-19 symptoms

It’s possible that people may be experiencing at least two of these syndromes at the same time, the report says. Furthermore, it suggests that long-Covid can be cyclical with symptoms fluctuating in severity and moving around the body, causing unpredictable effects across the lungs, heart, kidneys, brain, skin, muscles, ligaments, or gastrointestinal system.

Tens of thousands of people worldwide have already joined online forums on social media to share their experience of long-Covid. One of the largest groups on Facebook already has over 20,000 members. For part of this new review, the NIHR team held a focus group with 14 members of the Long COVID Facebook group, including both post-hospitalized and non-hospitalized patients, and discussed their experience.

“I thought recovery would be much easier compared to the nightmare I had already endured except it was the beginning of a different kind of a nightmare – ‘Long Covid’. Although I see this as silent, it is quite debilitating with symptoms of severe fatigue, recurrent sore throats and brain fog," Pretty Ngwenya, who first fell sick in April 2020 said in a testimony for the report.

Lee David Bowen, who is believed to have caught Covid-19 in February, added: “I currently feel I am living in a “Covid” cycle of symptoms (fever, cough and metallic taste), extreme fatigue and brain fog then a few days of normality. Slowly, after nearly six months I am slowly beginning to see more ‘normal’ days but as soon as I begin to feel better the cycle starts again."

It’s not known how many people are experiencing long-lasting health concerns after recovering from Covid-19, although other research has suggested it’s likely to be a significant number of people. 

A recent preliminary study from South Korea surveyed 65 recovered Covid-19 patients and found that 91.1 percent of them were suffering from at least one lasting side-effect, most often tiredness followed by lack of concentration or so-called "brain fog.” Another recent study asked 120 people who were hospitalized with Covid-19 in France how they felt over 100 days after being first admitted, concluding that many were suffering from fatigue (55 percent), difficult breathing (42 percent), loss of memory (34 percent), lack of concentration (28 percent), and sleep disorders (30 percent).

The new review by NIHR argues that their findings could help to explain why many people experiencing lingering symptoms of Covid-19 after their initial bout of illness are struggling to be properly recognized and treated by healthcare services.

“This review highlights the detrimental physical and psychological impact that ongoing COVID is having on many people’s lives, and how healthcare services have at times struggled to manage these new and fluctuating patterns of symptoms and problems,” Dr Elaine Maxwell, review author and Content Lead for NIHR’s Centre for Engagement and Dissemination, said in a statement. 

“Our aim is that healthcare services and staff will use this review to better understand the experiences patients have to deal with, and provide them with the access to treatment, care and support they need.”