Scientists estimate nearly 15% of people with the virus suffered tinnitus and nearly 8% suffered hearing loss.
Hearing loss and other auditory problems may be strongly linked to coronavirus, new research suggests.
Scientists estimate 7.6% of people infected with COVID-19 experience hearing loss, while 14.8% suffer tinnitus. They also found the prevalence of vertigo was 7.2%.
The researchers, Professor Kevin Munro and PhD researcher Ibrahim Almufarrij from The University of Manchester and Manchester Biomedical Research Centre, compiled data from 24 studies that identified an association between coronavirus and auditory and vestibular problems.
“If it is correct that something between 7% and 15% are having these symptoms, that’s something we should take very seriously,” Professor Kevin Munro, said director of the Manchester Centre for Audiology and Deafness. ”There are big implications for clinical services if this means there could be a big increase in the number of people coming forward.”
Hearing problems can be caused by other viruses – including measles, mumps and meningitis – which damage sensory cells in the inner ear.
It is not known why COVID-19 can cause these issues and researchers believe a wide variety of people have been affected. “There are some people who say the symptoms are ongoing. There are others who say it seems to have settled down a bit so there are lots of unknowns right now,” Prof Munro said.
The researchers’ data primarily used self-reported questionnaires or medical records to obtain coronavirus-related symptoms, rather than the more scientifically reliable hearing tests.
They are now conducting a more detailed clinical study which they hope will accurately estimate the number and severity of COVID-related hearing disorders in the UK. Professor Munro, is currently leading a year-long UK study to investigate the possible long-term impact of COVID-19 on hearing among people who have been previously treated in hospital for the virus.
His team hope to accurately estimate the number and severity of COVID-19 related hearing disorders in the UK, and discover what parts of the auditory system might be affected. They will also explore the association between these and other factors such as lifestyle, the presence of one or more additional conditions and critical care interventions.
A recent study led by Professor Munro, suggested that more than 13 per cent of patients who were discharged from a hospital reported a change in their hearing.
Ibrahim Almufarrij said: “Though the evidence is of varying quality, more and more studies are being carried out so the evidence base is growing. What we really need are studies that compare COVID-19 cases with controls, such as patients admitted to hospital with other health conditions”.
“Though caution needs to be taken, we hope this study will add to the weight of scientific evidence that there is a strong association between Covid-19 and hearing problems.”Professor Munro added: “Over the last few months I have received numerous emails from people who reported a change in their hearing, or tinnitus after having COVID-19.
“While this is alarming, caution is required as it is unclear if changes to hearing are directly attributed to COVID-19 or to other factors, such as treatments to deliver urgent care.”