New Test for Chronic Fatigue Syndrome Could Help COVID-19 Patients

Woman sitting on edge of bed waiting to get up.

PhotoAlto/Frederic Cirou / Getty Images

Key Takeaways

  • Researchers developed a new test to diagnose myalgic encephalomyelitis (ME), better known as chronic fatigue syndrome.
  • ME is a complex chronic disease affecting up to 2.5 million Americans.
  • Many COVID-19 long haulers are experiencing ME-like illness.

Researchers have developed a new test to diagnose myalgic encephalomyelitis (ME), also known as chronic fatigue syndrome (CFS).

The test stands out as the first successful molecular diagnostic tool for ME, a development that has been long anticipated by many healthcare providers and patients. This new tool opens up the possibility for differentiation between mild and severe cases of ME.

ME is a complex disorder characterized by extreme fatigue that lasts for at least six months and that can't be fully explained by an underlying medical condition. The fatigue worsens with physical or mental activity but doesn't improve by resting.

The results from the November study may also allow healthcare providers to potentially predict how patients will respond to certain medications, which could help them make treatment more personalized (and hopefully more effective) in the future. The findings were published in the journal Scientific Reports.

One of the study’s authors, Alain Moreau, PhD, a professor in the department of biochemistry and molecular medicine at the Université de Montréal, is hopeful the research can be used to diagnoses ME patients. “There [are] no laboratory test or biomarkers used for the diagnosis or prognosis of ME/CFS. We believe that our test is the first of its kind,” Moreau tells Verywell. “Clinicians usually establish their diagnosis by excluding all possible causes that could explain the symptoms associated with ME/CFS.”

This test, he hopes, will result in quicker diagnoses, and faster, more effective treatments.

How It Works

In order to test a patient, researchers attached an inflatable arm cuff to a patient's arm, which then provided mechanical stimulation. The result causes post-exertional malaise, one of the most common symptoms of ME, and provides an exact molecular signature. This makes it possible to differentiate between ME patients and those without the condition, as well as from patients living with related conditions such as fibromyalgia.

Post-exertional malaise refers to a worsening of ME symptoms after minimal physical or mental exertion. It typically occurs 12 to 48 hours after activity and can last for days or even weeks.

Next comes a blood test. The test detected a change in abundance of 11 microRNAs in patients' blood compared with blood drawn before the test. MicroRNAs are small non-coding RNA molecules that act inside cells to regulate gene expression—and have been the subject of research interest as potential diagnostic tools for several conditions. 

Most of these 11 microRNAs found were involved in regulating immunity, which supports the idea that immune dysfunction plays a key role in ME. The findings are the first step in developing a molecular diagnostic test for the disease.

An increase or reduction of some of the microRNAs measured in the test can also help predict the patient’s therapeutic response to certain drugs, which improves the chances of finding the right therapy to personalize treatment.

The research team is now validating the test in other groups and continuing clinical trials. The test may allow for early detection of ME in people with persistent post-COVID-19 symptoms that are very similar to ME, making earlier intervention possible, the researchers add.

What This Means For You

In the future, tools like these may make it easier to diagnose ME. If you're a recovered COVID-19 patient and feel lingering symptoms like fatigue, talk to your healthcare provider about treatment and your next steps.

Lingering COVID-19 Symptoms

More than six months into the global COVID-19 pandemic, many who contract the virus are not fully recovering from their illness. Up to 35% of people diagnosed with COVID-19 were not back to their normal selves two to three weeks after testing positive, according to a July report by the Centers for Disease Control and Prevention (CDC).

Of the 292 people the CDC surveyed on post-COVID-19 recoveries, 35% reported fatigue. These patients who have yet to fully recover are commonly referred to as COVID-19 "long-haulers."

In a November 2020 letter to the editor of the journal Med Hypotheses, a group of doctors voiced their concerns about the lingering effects on COVID-19 patients. The doctors recommended more proactive testing for CFS in recovered COVID-19 patients.

Long-Haul COVID Doctor Discussion Guide

Get our printable guide for your next doctor's appointment to help you ask the right questions.

Doctor Discussion Guide Old Man

Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, has speculated that many long-haulers will develop ME. Previous research shows ME can be triggered by other infectious illnesses like mononucleosis, Lyme disease, and severe acute respiratory syndrome (SARS), which is another coronavirus disease.

"[The pandemic] will bring a huge number of new [ME/CFS] patients, and some of them are relatively young. That will create some devastating impacts for themselves and their families,” Moreau told TheScientist. “That’s why we need to hurry and hope that we will convince governments and funding agencies to [put more funding into the field].”

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Mayo Clinic. Chronic Fatigue Syndrome. September 24, 2020.

  2. Nepotchatykh, E., Elremaly, W., Caraus, I. et al. Profile of circulating microRNAs in myalgic encephalomyelitis and their relation to symptom severity, and disease pathophysiologySci Rep. 2020;10(19620). doi:10.1038/s41598-020-76438-y

  3. Ardekani AM, Naeini MM. The Role of MicroRNAs in Human DiseasesAvicenna J Med Biotechnol. 2010;2(4):161-179.

  4. Tenforde MW, Kim SS, Lindsell CJ, et al. Symptom Duration and Risk Factors for Delayed Return to Usual Health Among Outpatients with COVID-19 in a Multistate Health Care Systems Network — United States, March–June 2020. MMWR Morb Mortal Wkly Rep. 2020;69:993-998. doi:10.15585/mmwr.mm6930e1

  5. Perrin R, Riste L, Hann M, Walther A, Mukherjee A, Heald A. Into the looking glass: Post-viral syndrome post COVID-19Med Hypotheses. 2020;144:110055. doi:10.1016/j.mehy.2020.110055

  6. Harvard Health Publishing. The tragedy of the post-COVID “long haulers”. October 15, 2020.

By Erica Gerald Mason
Erica Gerald Mason is an Atlanta-based writer with a focus on mental health and wellness.