Throughout 2020 COVID-19 had us hiding out at home, washing our hands, wiping down surfaces and masking up. Quite a bit wasn’t known for some time. We knew about flu-like symptoms and disturbances in smell and taste, but not enough about the full spectrum of effects. A year later now, evidence is emerging about symptoms of the disease beyond those that were initially reported. Tinnitus, Hearing loss and balance disorders were noted in a review by the Manchester Centre for Audiology and Deafness (ManCAD) of 56 studies published in 2020. The evidence remains tentative at this stage as it is only based on self-reports of problems. Their conclusion was that “There are multiple reports of audio-vestibular symptoms associated with COVID-19. However, there is a dearth of high-quality studies comparing COVID-19 cases and controls.” Senior Author Kevin Munro, professor of audiology at ManCAD states that there is a need for a carefully designed study to yield high quality data about the apparent association of these symptoms with COVID-19. Professor Munro is leading a year-long study in the UK comparing control patients with recovered patients who were hospitalized with COVID-19.
Why does this disease apparently cause hearing and balance problems and tinnitus? We have learned that the damage caused by COVID-19 can go beyond respiratory problems to immune reactions causing inflammation, and circulatory complications that may damage wide ranging sensory systems in the body. The problems may result from direct viral infections of the ear and connecting nerve pathways, excessive cytokine production causing inflammation, or blood clots in pathways supporting delicate structures of the inner ear.
As more is learned about the nature and extent of the association of these symptoms with the disease, a better understanding of the root causes of the symptoms will emerge, bringing possible treatments into practice.
What should you do if you have had COVID-19 and think you may have trouble hearing or a change in tinnitus? Proactively scheduling a hearing check will establish an objective level to inform your physician and you about your hearing and establish a baseline for comparison in the future if necessary.
Ibrahim Almufarrij & Kevin J. Munro (2021): One year on: an updated systematic review of SARS-CoV-2, COVID-19 and audio-vestibular symptoms, International Journal of Audiology, DOI: 10.1080/14992027.2021.1896793