ME/CFS Awareness Day

May 12 honors those whose lives are affected by ME/CFS.

What to know

May 12 is Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) International Awareness Day. This day coincides with the birthday of Florence Nightingale, the British nurse and statistician, founder of modern nursing. She became chronically ill from a bacterial infection and was often bedridden later in life. ME/CFS was not defined in her lifetime, but many medical historians believe she developed an ME/CFS-like illness.

Engraving from 1885 of Florence Nightingale the founder of modern nursing.

What to know about ME/CFS

People with ME/CFS experience extreme fatigue that leaves them unable to do their usual activities. In addition, they experience worsening of symptoms after physical or mental activity and sleep problems. They may have lightheadedness, dizziness, problems thinking and concentrating, and pain.

Although factors other than infections may also be associated with ME/CFS, it is considered a long-term consequence of infections. Most recently, researchers have documented the overlap of the symptoms of ME/CFS and Long COVID. Medical guidance for people with Long COVID who have severe fatigue is based on healthcare providers' experience with ME/CFS.

Sharing new insights

In December 2023, CDC released a new national estimate of how many people in the U.S. have ME/CFS. The 2021-2022 National Health Interview Survey asked adults whether they had been diagnosed with ME/CFS by a healthcare provider. Data showed 1.3% of adults, or about 3.3 million people, currently had ME/CFS. Women were more likely than men to have the illness. The actual numbers may be higher, as previous studies suggest many people with ME/CFS have not been diagnosed.

CDC's work with ME/CFS guided development of a new webpage, Chronic Symptoms Following Infections, launched in October 2023. Many people with ME/CFS or people with long-term symptoms after infections may not recognize they have an illness. This webpage gives an overview of the possible causes of long-term symptoms following infections and how they affect people. It encourages talking with a healthcare provider about symptoms, and touches on the infections that have been linked to chronic symptoms.


CDC funded the CDC Foundation to launch the Infection-Associated Chronic Conditions Understanding and Engagement (ICUE) program in December 2022. The program brings together patient partners and community organizations to raise awareness of long-term health problems following infections. Patient and community groups aim to draw attention to the medical and support needs of people living with these health conditions.

CDC regularly hosts Stakeholder Engagement and Communication (SEC) calls to share information on ME/CFS.

The May 2023 SEC call featured Dr. Jacek Skarbinski from Kaiser Permanente, who described findings from the STOP ME/CFS Study. He discussed the collaboration with the California Emerging Infections Program on ME/CFS-like illness following COVID-19.

In December 2023, Dr. Bhupesh K. Prusty and Dr. Dawei Li presented research on viruses in ME/CFS.


CDC continues to educate healthcare providers about ME/CFS. In September 2023, CDC and Medscape launched a new continuing medical education (CME) course. The course is "ME/CFS Diagnoses and Management in the Age of COVID: Expert Insights," with credits available until September 2025. This activity provides further support to help healthcare providers better diagnose and manage ME/CFS. More CME courses can be found at the Medscape ME/CFS CME page.

Working with the National Association of School Nurses, we provide training on ME/CFS symptoms through the School-Based Active Surveillance (SBAS) project. We also developed and submitted ME/CFS questions for consideration to the National Board of Certification for School Nurses (NBCSN) Examination Committee.

Join CDC in supporting the ME/CFS community

You can join CDC in supporting the ME/CFS community:

  1. Wear blue to show support for people with ME/CFS on May 12.
  2. Help spread the word on social media using hashtag #MECFSAwareness.
  3. Share personal stories with neighbors and friends.