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Nearly 90% of those living with Long COVID have not returned to full health

7 Nov 2022

Nearly 90% of those living with Long COVID have not returned to their pre-Covid level of health, a new study finds today (Monday 07/11/22)


Nearly 90% of those living with Long COVID have not returned to their pre-Covid level of health, a new study finds today (Monday xxx).

The study of 988 participants conducted by APC Microbiome Ireland, a world-leading SFI research centre based at University College Cork (UCC), in conjunction with Cork University Hospital (CUH) and Long Covid Advocacy Ireland, provides greater insight into impact of Long COVID on quality of life, mental health and physical health of people in Ireland.

More than 2 out of 3 participants continue to experience fatigue, post-exertional malaise, palpitations, chest pain, stomach upset/nausea, memory problems, muscle pain or joint pain. The median number of Long COVID symptoms reported was 8 for each person, highlighting the substantial burden of this disease. The median reported time since the initial COVID-19 infection was 12 months.  

6 out of every 10 missed workdays

A high proportion of Long COVID patients reported that they still have a moderate to severe limitation in their ability to carry out their usual daily activities. Nearly 4 of 10 people were severely limited in their ability to work and 6 of every 10 have missed workdays (at some stage) due to their Long Covid symptoms. 16% of respondents were unable to work at the time of the survey due to Long COVID and were receiving social welfare supports.

The survey was produced in a researcher-clinician-patient partnership involving Professor Liam O’Mahony,APC Principal Investigator and UCC Professor of Immunology, Dr Corinna Sadlier, Consultant in Infectious Diseases at CUH, and Ms Tanja Buwalda, Long COVID sufferer and representative of ‘Long Covid Advocacy Ireland’.

This working group included patient engagement to ensure the survey would impact patients in a targeted and meaningful way, and ultimately help inform care pathways in the treatment of Long COVID.

SARS-CoV-2 infection not only impacts the lungs

Professor O’Mahony said: "This survey highlights that SARS-CoV-2 infection not only impacts the lungs but can have significant long-term effects on multiple organ systems following clearance of the acute SARS-CoV-2 infection in many Irish people who were otherwise healthy previously. The reasons why some people develop Long COVID, and others do not, are still unclear. While many different biological mechanisms have been proposed, we are focusing on the role of the immune system and the microbiome in these complicated disease processes.”

“The majority of people surveyed had a mild-moderate severity of initial COVID-19 disease and the majority did not require hospital treatment at that time. A wide range of body systems are impacted by Long COVID, as demonstrated by systemic, respiratory, cardiovascular, gastrointestinal, neuropsychiatric or musculoskeletal symptoms. Fatigue is the single most frequent symptom reported.”  Professor O’Mahony continued.

Dr Corinna Sadlier said: “The study demonstrates the significant and wide-ranging impacts Long COVID is having not only on physical health, but also on ability to carry out usual daily activities, return to employment and overall quality of life. Another interesting aspect of this research are the clusters of multisystem symptoms or Long COVID phenotypes that are emerging. While there remains a huge amount to learn about post COVID illness, there is a clear and compelling need for dedicated cross disciplinary specialist services to treat Long COVID patients. In parallel, research is urgently required to identify mechanisms underlying Long COVID symptoms as well as effective treatments to improve outcomes for this patient group.”

Ms Tanja Buwalda said: “This study clearly shows that Long COVID demands urgent national attention from the government and health system. Thousands of people are suffering needlessly because they do not have access to multidisciplinary clinics or effective treatments. With recent waves of new infections, we should expect even more Long Covid illnesses to arise. We feel that tackling this large and ongoing problem requires a collaborative approach.”

“By conducting this research in collaboration with UCC, APC and CUH, as a Patient Advocacy group, we are helping to set the agenda for how Long Covid should be addressed, which is on a multi-disciplinary level, reflecting the illness's multi-system complexity. While the Long Covid Advocacy Ireland appreciates this preliminary study, we believe that much more must be done in terms of patient care, diagnosis, and treatments, as well as the underlying root causes of Long Covid.”


For more on this story contact:


The study is published on HRB Open Research:


Professor Liam O’Mahony is available for interview.

For further information, contact Kate O’Sullivan, UCC Media and Communications, and 087 764 6931.


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