MANCHESTER, United Kingdom — The public is very familiar with COVID-19’s ability to disrupt a patient’s sense of smell and taste. Now, a new study warns the coronavirus may lead to hearing loss and other auditory issues as well.
Scientists from the University of Manchester and NIHR Manchester Biomedical Research Centre (BRC) performed a review of relevant research evidence. That process led them to conclude there is a strong association between COVID-19 and hearing problems. In all, they identified 56 prior research projects that note a connection between COVID and hearing loss.
After pooling data from 24 studies, researchers estimate hearing loss prevalence due to COVID-19 occurs in seven percent of cases. Tinnitus (ringing in the ears) occurs in 14.8 percent of cases and vertigo 7.2 percent of the time. Most of the data helping the team reach these conclusions comes from medical records or self-reported questionnaires. Researchers admit there is a need for more scientifically reliable evidence, such as actual hearing tests.
“There is an urgent need for a carefully conducted clinical and diagnostic study to understand the long-term effects of COVID-19 on the auditory system. It is also well-known that viruses such as measles, mumps and meningitis can cause hearing loss; little is understood about the auditory effects of the SARS-CoV-2 virus,” says Kevin Munro, Professor of Audiology at The University of Manchester and Manchester BRC Hearing Health Lead, in a media release. “Though this review provides further evidence for an association, the studies we looked at were of varying quality so more work needs to be done.”
Tracking COVID’s impact on the ears
Currently, Prof. Munro is leading a team investigating the potential long-term impact of COVID-19 on recovered individuals’ hearing. The hope is that this initiative will be able to estimate how many recovered COVID patients in the U.K. are dealing with subsequent hearing issues. They also want to determine which specific areas of the auditory system the virus is affecting.
A recent investigation discovered over 13 percent of discharged COVID-19 patients report at least some change in their hearing.
“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,” adds study co-author Ibrahim Almufarrij. “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.”
“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,” Munro concludes. “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.”
The study is published in the International Journal of Audiology.