Those suffering from the condition have reported a wide range of symptoms.
Figures from the Office for National Statistics (ONS) in the UK show there has been a marked increase in the number of people with self-reported long Covid that has lasted for at least a year.
Here are answers to the key questions about the condition.
Long Covid, also known as post-Covid syndrome, is used to describe the effects of the virus that continue for weeks or months beyond the initial illness.
There are a wide range of common long Covid symptoms including fatigue, shortness of breath, chest pain or tightness, problems with memory and concentration, insomnia, dizziness, pins and needles, joint pain, depression and anxiety, tinnitus, earaches, feeling sick, diarrhoea, stomach aches, loss of appetite, a high temperature, cough, headaches, sore throat, changes to sense of smell or taste or skin rashes.
In a recent study, 79.5pc of people living with long Covid reported problems with their usual activities, more than half (56.2pc) reported problems with their mobility.
Recent studies suggest that one in seven people that become infected with Covid-19 suffer long Covid, meaning millions of people, as there are over 170m confirmed cases globally.
While there is no defined period you have to have symptoms before it’s classified as long Covid, it’s generally accepted you must have the symptoms for 12 weeks or more after infection.
People of any age are thought to be affected, with children as young as four and pensioners over the age of 85 reporting ongoing symptoms.
The ONS has found that prevalence of self-reported long Covid was greatest in people aged 35 to 69, females, those living in the most deprived areas, those working in health or social care, and those with another activity-limiting health condition or disability.
Scientists from the UK’s National Institute for Health Research, who reviewed the available evidence of the symptoms in October 2020, believe ongoing Covid may not be one illness but at least four different syndromes.
These have been broadly categorised as: post-intensive care syndrome, post-viral fatigue syndrome, permanent organ damage and long-term Covid syndrome.
While there are no dedicated long Covid units within the HSE, people are urged to contact their GP if they are worried about symptoms four weeks or more after having Covid-19.
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