Individuals Who’ve Had COVID Could Be 8 Times As Likely To Develop The Chronic Condition ME/CFS

“This research underscores the urgency for healthcare providers to recognize post-COVID-19 ME/CFS,” said first author Dr Suzanne D. Vernon, research director at the Bateman Horne Center, in a statement sent to IFLScience. 

ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome) is a complex chronic health condition that can sometimes be traced to a prior infection. Even if the initial infection was mild and the person made a full recovery, a debilitating array of symptoms can start to arise down the line.

If that sounds familiar in the context of COVID-19, that’s because there are a lot of parallels between ME/CFS and long COVID. While some patients with long COVID may have organ damage caused by the virus itself, or be dealing with the long-term effects of hospitalization, there are still others who recovered from a mild bout of COVID only to develop symptoms like brain fog, fatigue, and dizziness. 

But while long COVID is a comparatively new problem, ME/CFS and the concept of post-viral illnesses have been known about for some time. Nonetheless, many patients report difficulty accessing diagnosis and care, and face stigma, misunderstandings, and conflicting advice, as evidenced in testimonials such as this patient account published in the journal Work. 

It’s now known beyond doubt that ME/CFS is a biological illness that affects multiple bodily systems. There are different degrees of severity, and the condition can have a significant impact on day-to-day activities. A key feature for many patients is post-exertional malaise, where symptoms like fatigue worsen after physical activity. The Centers for Disease Control and Prevention says that around a quarter of people with the condition are confined to bed at some point in their illness. 

Given all we have learned about long COVID since the pandemic was declared almost five years ago, the researchers behind the new study wanted to look at the potential relationship between COVID and ME/CFS.

They turned to data from the RECOVER Initiative, an NIH-funded project that was set up to be “the world’s most comprehensive and diverse” study of long COVID. This analysis included 11,785 participants with a history of SARS-CoV-2 infection and 1,439 who had not been infected. 

The team assessed how many of the participants met the diagnostic criteria for ME/CFS at least 6 months after having COVID-19. It’s worth noting that these criteria rely on self-reporting of symptoms, which was highlighted as a limitation of the study. 

ME/CFS was found to occur in 4.5 percent of infected participants versus just 0.6 percent of uninfected participants. Almost 90 percent of those who met the criteria for ME/CFS had also been identified as among the most symptomatic long COVID patients, highlighting the crossover between the two conditions. 

“These findings provide additional evidence that infections, including those caused by SARS-CoV-2, can lead to ME/CFS,” writes the National Institute of Neurological Disorders and Stroke in a statement on the study. 

The most commonly reported symptoms by the cohort were post-exertional malaise, orthostatic intolerance (dizziness when standing up), and cognitive impairments. These are also symptoms reported by many long COVID patients, and the authors say there’s an urgent need for more research to understand why COVID can lead to chronic illness in some, and who may be predisposed. 

“This research underscores the urgency for healthcare providers to recognize post-COVID-19 ME/CFS. Early diagnosis and proper management can transform lives,” said Vernon. 

The study is published in the Journal of General Internal Medicine.

An earlier version of this story was published in January 2025.