- The largest global study of “Long COVID” concluded that many patients experience COVID-19 symptoms for at least six months after the initial infection with the novel coronavirus.
- Some of the patients surveyed were unable to return to work for weeks or months and had to take more time off to recover.
- The scientists said the most common Long COVID symptoms include fatigue, tiredness, and “brain fog.” They observed several less common symptoms as well, many of which were neurological.
Not all patients who recover from COVID-19 do so quickly. Some continue to experience symptoms even after their immune systems have eliminated the virus. They’ve been called “long haulers,” with their condition often described as “Long COVID.” A variety of studies have shown that the number of people affected by Long COVID can be quite significant and have revealed the symptoms they might experience. One of the most troubling aspects of Long COVID is that it doesn’t just replicate the symptoms that appear during COVID-19. People have experienced all sorts of unusual problems that have ultimately been linked to the coronavirus infection.
Doctors still can’t explain why Long COVID presents itself or how long it will last, but they’re certainly aware of how serious it can be. One health expert speculated recently that Long COVID symptoms could last up to a year after the initial infection, although there was no data to back those claims up. Now, the largest global study of Long COVID shows that the symptoms can linger for as long as six months, impacting regular life in the process.
The study was published in preprint form on medRxiv (via CNBC), meaning it hasn’t been peer-reviewed.
The study shows that many long haulers cannot return to work at full capacity for up to six months after infection. More than 45% of respondents required a reduced work schedule, and 22.3% were not working at the time of the survey because of their health conditions. The researchers surveyed 3,762 people aged 18 to 80 from 56 countries. They recorded 205 symptoms in 10 organ systems, and 66 of those symptoms were traced over seven months. Respondents experienced symptoms from nine organ systems on average.
The study looked at confirmed and suspected COVID-19 patients with illness lasting more than 28 days and onset before June. That way, they were able to follow up on patients for six months.
Fatigue, tiredness, and cognitive dysfunction (brain fog) were among the most frequent Long COVID symptoms. People still experiencing symptoms at six months displayed an average of 13.8 symptoms in month seven. Some 86% of respondents experienced relapses in symptoms triggered by exercise, physical and mental activity, and stress.
The study also highlighted some of the less common symptoms that COVID-19 patients who develop Long COVID might experience:
Participants also experienced symptoms that are not commonly mentioned in public discussion of Long COVID, and may benefit from further attention. These include but are not limited to: anaphylaxis and new allergies, seizures, suicidality, changes in sensitivity to medication, vision loss, hearing loss, and facial paralysis. Several of these symptoms, as well as the more commonly reported Long COVID symptoms, overlap with symptoms of Mast Cell Activation Syndrome (MCAS), possibly warranting further exploration into the role of mast cells in Long COVID.
The researchers also focused on the neurological symptoms that can appear in Long COVID, some of which impacted work performance:
Memory and cognitive dysfunction, experienced by over 85% of respondents, were the most pervasive and persisting neurologic symptoms in this cohort, equally common across all ages, and with substantial impact on work. Headaches, insomnia, vertigo, neuralgia, neuropsychiatric changes, tremors, sensitivity to noise and light, hallucinations (olfactory and other), tinnitus, and other sensorimotor symptoms were also all common among respondents, and may point to larger neurological issues involving both the central and peripheral nervous system. This area is particularly important to study, as others have found neurological symptoms may be more common in nonhospitalized patients, and that those with neurological symptoms may have impaired seroconversion.
“Patients with Long COVID report prolonged multisystem involvement and significant disability. Most had not returned to previous levels of work by 6 months. Many patients are not recovered by 7 months, and continue to experience significant symptom burden,” the researchers concluded, including “significant impact to patients’ lives and livelihoods.”
The researchers have also pointed out that the respondents had a relatively high socioeconomic status, which allowed them to take time off work. But not all survivors suffering from Long COVID will have the same luxury.
The study “emphasizes the importance of all patients having adequate time off to recover, being able to qualify for disability benefits if long-term assistance is needed, and receiving accommodations at work including telecommuting, flexible hours, and phased returns. Lower wage earners may find it especially challenging to access these accommodations and benefits, particularly in locations without robust legal protections for disabled workers, yet they are in need of these protections the most to ensure financial stability,” the researchers wrote.
While this study was limited to observing Long COVID for six months, more research will be required to determine the average length of symptoms. Doctors will have to find therapies to ameliorate symptoms and reduce the length of Long COVID, and studies like this one could help them understand Long COVID better.
