For many of us, becoming ill with a virus might put us on the couch for a week or two.
It’s frustrating, but after recovering we can generally get back to the things we’re used to.
But for some people, contracting a viral infection can be life-altering.
It can cause months, years or even a lifetime of debilitating symptoms that drastically reduce their quality of life.
These symptoms, sometimes called “post-viral fatigue syndrome”, have been reported by sufferers of many viral diseases including influenza, glandular fever, SARS, and now COVID-19.
What are the symptoms?
The World Health Organisation has classified post-viral fatigue syndrome under the section of “diseases of the nervous system”. It’s defined as:
…a complex medical condition, characterised by long-term fatigue and other symptoms. These symptoms are to such a degree that they limit a person’s ability to carry out ordinary daily activities.
Despite the word “fatigue”, the symptoms can be broader and more debilitating than simple tiredness.
They can include a sore throat, aches and pains across the body, blood pressure changes, gastric upsets such as irritable bowel syndrome, headaches, sleep disturbance, depression, and dizziness.
More severe neurological symptoms can also occur, including new sensitivities or allergic reactions, and burning or prickling sensations in the limbs. Many COVID-19 patients, for example, report a prolonged loss of smell and taste.
A key feature of the condition is that symptoms can suddenly worsen following only minimal physical or mental activity.
The symptoms are essentially the same as those of chronic fatigue syndrome, also called myalgic encephalomyelitis or ME, which is why the WHO places them under the same category of neurological disorders.
If you went to see a doctor, the clinical assessment for post-viral fatigue syndrome would be the same as for chronic fatigue syndrome.
However, not everybody who gets chronic fatigue syndrome has had a virus, which may explain why both terms persist. There are no current diagnostic tests for post-viral fatigue syndrome, and a diagnosis can only be made based on a series of symptoms.