Onset of ME/CFS

The onset of ME/CFS can be sudden (acute) or gradual. Sudden onset is more common. Dr. Melvin Ramsay and Dr. Byron Hyde both describe sudden/acute onsets for myalgic encephalomyelitis (ME) as oppose to ME/CFS being acute or gradual. In cases of sudden onset, it is usually easy to identify the trigger of the illness, such as physical trauma, overwhelming stress, or a viral/bacterial infection. Children, particularly adolescents, will more likely have an acute illness like the flu or mononucleosis as their onset.

Acute symptoms develop over hours to days. 85% of patients report a trigger. 72% of ME/CFS patients report that a bacterial or a viral infection was their onset of ME/CFS; 4.5% trauma; 4.5% surgery or childbirth; 2.2% allergic reaction; 1.7% stress or trauma.

Genes are being considered for a risk in developing ME/CFS as sometimes several members of the same family will develop ME/CFS.

Pre-onset triggers

The International Consensus Criteria (ICC) Primer includes a patient assessment form, which includes factors that may have triggered ME, these can be infectious (for example, a virus), or non-infectious (for example, exposure to chemical toxins or severe physical injury).

Infectious exposure or events

• minor infections, vaccination, upper respiratory infections, sinusitis, pneumonia, gastrointestinal illness (after sinusitis or pneumonia), dental infections, vaginal infection, cystitis, prostatitis, blood transfusion
• exposure to: sick people, unfamiliar infectious agents when traveling, particularly following vaccinations, contaminated water, poor quality recycled air

Non-infectious exposure or events

• exposure to: chemical toxins, heavy metals, or moulds
• severe physical trauma e.g. whiplash/spinal injury/surgery
• anaesthetics
• undue stress
• steroids

Other triggers have been recognized besides these, and some people report several potential triggers or no known cause.

Is ME always caused by a virus?

A small number of ME patient charities, for example The Hummingbirds' Foundation for ME hold the view that ME is always caused by a virus, but chronic fatigue syndrome (CFS) may have non-viral triggers, and do not recognize bacterial infections or non-infectious events as a potential cause or trigger.

The onset events recognized as potential causes or triggers in the ICC are based on events prior to illness that have been reported by patients meeting the diagnostic criteria for ICC ME or based on the consensus of experts. The exact cause has not yet been identified in research. Chu et al. (2019) reported on pre-onset events for patients meeting the CFS Fukuda criteria only.

See also

Viral onset hypothesis.

Development of ME

The International Consensus Criteria for ME recognizes that ME can develop

• suddenly
• gradually, or
• after an infectious disease (for example, viral or bacterial outbreaks within a community)
• have a non-infectious event shortly before onset
• there may not be any potential trigger identified when ME begins

Criteria

• In the Holmes criteria, description of the main symptom complex as initially developing over a few hours to a few days is an optional criterion for diagnosis, under the section Minor Symptom Criteria.

Notable studies

• 2020, Genetic risk factors of ME/CFS: a critical review - (Full text)
• 2019, Onset patterns and course of myalgic encephalomyelitis/chronic fatigue syndrome (Full text)
• 2016, Genome-wide association analysis identifies genetic variations in subjects with myalgic encephalomyelitis/chronic fatigue syndrome (Full Text)
• 2014, Two age peaks in the incidence of chronic fatigue syndrome/myalgic encephalomyelitis: a population-based registry study from Norway 2008-2012 - (Full text)

See also

• Bacterial disease onset
• Viral onset hypothesis
• Possible Infectious agents for ME/CFS onset
• Epidemiology
• Risk factors
• Pediatric
• Prevelance
• Prognosis
• Corticosteroids given during acute viral infection may trigger myalgic encephalomyelitis 
• Pesticide exposure link to ME/CFS

 Learn more

• Dr. Ron Davis Gives an Update on ME/CFS Gene Research - YouTube
• Presentation and Clinical Course of ME/CFS - CDC
• 2018, Onset patterns of chronic fatigue syndrome and myalgic encephalomyelitis

See myalgic encephalomyelitis.

See chronic fatigue syndrome.

International Consensus Criteria (ICC) - A set of diagnostic criteria, based on the Canadian Consensus Criteria, that argued for the abandonment of the term "chronic fatigue syndrome" and encouraged the sole use of the term "myalgic encephalomyelitis".

See International Consensus Criteria.

genome an organism's complete set of DNA, including all of its genes

Centers for Disease Control and Prevention (CDC) - The Centers for Disease Control and Prevention is a U.S. government agency dedicated to epidemiology and public health. It operates under the auspices of the Department of Health and Human Services.

See Centers for Disease Control and Prevention.

chronic disease a disease or condition that usually lasts for 3 months or longer and may get worse over time. Chronic diseases are long-term (typically incurable and requiring long-term management) but are not necessarily severe.

myalgic encephalomyelitis (M.E.) - A disease often marked by neurological symptoms, but fatigue is sometimes a symptom as well. Some diagnostic criteria distinguish it from chronic fatigue syndrome, while other diagnostic criteria consider it to be a synonym for chronic fatigue syndrome. A defining characteristic of ME is post-exertional malaise (PEM), or post-exertional neuroimmune exhaustion (PENE), which is a notable exacerbation of symptoms brought on by small exertions. PEM can last for days or weeks. Symptoms can include cognitive impairments, muscle pain (myalgia), trouble remaining upright (orthostatic intolerance), sleep abnormalities, and gastro-intestinal impairments, among others. An estimated 25% of those suffering from ME are housebound or bedbound. The World Health Organization (WHO) classifies ME as a neurological disease.

brainstem Region of the midbrain in adults, includes midbrain, pons, and medulla oblongata and develops.

myalgic encephalomyelitis (M.E.) - A disease often marked by neurological symptoms, but fatigue is sometimes a symptom as well. Some diagnostic criteria distinguish it from chronic fatigue syndrome, while other diagnostic criteria consider it to be a synonym for chronic fatigue syndrome. A defining characteristic of ME is post-exertional malaise (PEM), or post-exertional neuroimmune exhaustion (PENE), which is a notable exacerbation of symptoms brought on by small exertions. PEM can last for days or weeks. Symptoms can include cognitive impairments, muscle pain (myalgia), trouble remaining upright (orthostatic intolerance), sleep abnormalities, and gastro-intestinal impairments, among others. An estimated 25% of those suffering from ME are housebound or bedbound. The World Health Organization (WHO) classifies ME as a neurological disease.

myalgic encephalomyelitis (M.E.) - A disease often marked by neurological symptoms, but fatigue is sometimes a symptom as well. Some diagnostic criteria distinguish it from chronic fatigue syndrome, while other diagnostic criteria consider it to be a synonym for chronic fatigue syndrome. A defining characteristic of ME is post-exertional malaise (PEM), or post-exertional neuroimmune exhaustion (PENE), which is a notable exacerbation of symptoms brought on by small exertions. PEM can last for days or weeks. Symptoms can include cognitive impairments, muscle pain (myalgia), trouble remaining upright (orthostatic intolerance), sleep abnormalities, and gastro-intestinal impairments, among others. An estimated 25% of those suffering from ME are housebound or bedbound. The World Health Organization (WHO) classifies ME as a neurological disease.

myalgic encephalomyelitis (M.E.) - A disease often marked by neurological symptoms, but fatigue is sometimes a symptom as well. Some diagnostic criteria distinguish it from chronic fatigue syndrome, while other diagnostic criteria consider it to be a synonym for chronic fatigue syndrome. A defining characteristic of ME is post-exertional malaise (PEM), or post-exertional neuroimmune exhaustion (PENE), which is a notable exacerbation of symptoms brought on by small exertions. PEM can last for days or weeks. Symptoms can include cognitive impairments, muscle pain (myalgia), trouble remaining upright (orthostatic intolerance), sleep abnormalities, and gastro-intestinal impairments, among others. An estimated 25% of those suffering from ME are housebound or bedbound. The World Health Organization (WHO) classifies ME as a neurological disease.

central nervous system (CNS) - One of the two parts of the human nervous system, the other part being the peripheral nervous system. The central nervous system consists of the brain and spinal cord, while the peripheral nervous system consists of nerves that travel from the central nervous system into the various organs and tissues of the body.

The limbic system is a group of structures between the forebrain and hindbrain mostly linked to emotions, memories and behavior. Includes the amygdala, limbic cortex, hypothalamus, cingulate gyrus, parahippocampal gyrus, hippocampus and hippocampal formation, dentate gyrus, subicular complex and septal area.

limbic system The limbic system is a group of structures between the forebrain and hindbrain mostly linked to emotions, memories and behavior. Includes the amygdala, limbic cortex, hypothalamus, cingulate gyrus, parahippocampal gyrus, hippocampus and hippocampal formation, dentate gyrus, subicular complex and septal area.

ganglion A ganglion is a group of neuron cell bodies in the peripheral nervous system. Plural: ganglia / ganglions

central nervous system (CNS) - One of the two parts of the human nervous system, the other part being the peripheral nervous system. The central nervous system consists of the brain and spinal cord, while the peripheral nervous system consists of nerves that travel from the central nervous system into the various organs and tissues of the body.